https://glycan.mit.edu/CFGparadigms/api.php?action=feedcontributions&feedformat=atom&user=Gillian+AirCFGparadigms - User contributions [en]2026-06-15T04:49:29ZUser contributionsMediaWiki 1.35.13https://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1599Influenza hemagglutinin H32011-04-19T22:45:53Z<p>Gillian Air: /* Biological roles of GBP-ligand interaction */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22) </ref>. Occasionally human H3N2 HAs bind to 2-3 linked sialic acids, such as sialyl-Lewis x <ref>Stevens, J., Chen, L.-M., Carney, P.J., Garten, R., Foust, A., Le, J., Pokorny, B.A., Manojkumar, R., Silverman, J., Devis, R., Rhea, K., Xu, X., Bucher, D.J., Paulson, J.C., Paulson, J., Cox, N.J., Klimov, A., Donis, R.O., 2010. Receptor specificity of influenza A H3N2 viruses isolated in mammalian cells and embryonated chicken eggs. Journal of Virology 84, 8287-8299.</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. Using MAA and SNA lectins, the upper respiratory tract appears to have more 2-6 linked sialic acid while 2-3 sialic acid appears more abundant in the lungs, but relationship between the different specificities of H3N2 HAs and the cell types infected remains unclear <ref> NICHOLLS, J., CHAN, R., Russell, R., Air, G., PEIRIS, J., 2008. Evolving complexities of influenza virus and its receptors. Trends in Microbiology 16, 149-157. </ref>. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]). The sialyltransferases that generate ligands for most H3 subtype hemagglutinins are ST6Gal1, ST6GalII, ST6GalNAc1, ST6GalNAcII, ST6GalNAcIV.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis is still unclear, but in the low pH of the endosomal compartment, the HA undergoes a large conformational change <ref>Bullough et al “Structure of influenza hemagglutinin at the pH of membrane fusion”. Nature 371: 37-43 (1994)</ref> that brings about fusion of the viral membrane with the cell membrane so that viral nucleocapsids are released, enter the nucleus and initiate viral transcription and replication.<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1598Influenza hemagglutinin H32011-04-19T22:38:47Z<p>Gillian Air: /* Carbohydrate ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22) </ref>. Occasionally human H3N2 HAs bind to 2-3 linked sialic acids, such as sialyl-Lewis x <ref>Stevens, J., Chen, L.-M., Carney, P.J., Garten, R., Foust, A., Le, J., Pokorny, B.A., Manojkumar, R., Silverman, J., Devis, R., Rhea, K., Xu, X., Bucher, D.J., Paulson, J.C., Paulson, J., Cox, N.J., Klimov, A., Donis, R.O., 2010. Receptor specificity of influenza A H3N2 viruses isolated in mammalian cells and embryonated chicken eggs. Journal of Virology 84, 8287-8299.</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. Using MAA and SNA lectins, the upper respiratory tract appears to have more 2-6 linked sialic acid while 2-3 sialic acid appears more abundant in the lungs, but relationship between the different specificities of H3N2 HAs and the cell types infected remains unclear <ref> NICHOLLS, J., CHAN, R., Russell, R., Air, G., PEIRIS, J., 2008. Evolving complexities of influenza virus and its receptors. Trends in Microbiology 16, 149-157. </ref>. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]). The sialyltransferases that generate ligands for most H3 subtype hemagglutinins are ST6Gal1, ST6GalII, ST6GalNAc1, ST6GalNAcII, ST6GalNAcIV.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1597Influenza hemagglutinin H32011-04-19T18:54:11Z<p>Gillian Air: /* Cellular expression of GBP and ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. Using MAA and SNA lectins, the upper respiratory tract appears to have more 2-6 linked sialic acid while 2-3 sialic acid appears more abundant in the lungs, but relationship between the different specificities of H3N2 HAs and the cell types infected remains unclear <ref> NICHOLLS, J., CHAN, R., Russell, R., Air, G., PEIRIS, J., 2008. Evolving complexities of influenza virus and its receptors. Trends in Microbiology 16, 149-157. </ref>. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]). The sialyltransferases that generate ligands for most H3 subtype hemagglutinins are ST6Gal1, ST6GalII, ST6GalNAc1, ST6GalNAcII, ST6GalNAcIV.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1577Influenza hemagglutinin H32011-04-13T04:40:35Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]). The sialyltransferases that generate ligands for most H3 subtype hemagglutinins are ST6Gal1, ST6GalII, ST6GalNAc1, ST6GalNAcII, ST6GalNAcIV.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1576Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:39:42Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
Receptors for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
No experiments have been published using glycosyltransferase knockout mice.<br />
<br><br />
<br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1575Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:39:14Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br><br />
Receptors for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
No experiments have been published using glycosyltransferase knockout mice.<br />
<br><br />
<br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1574Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:38:30Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br><br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
Receptors for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
No experiments have been published using glycosyltransferase knockout mice.<br />
<br><br />
<br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1573Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:37:14Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
Receptors for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
No experiments have been published using glycosyltransferase knockout mice.<br />
<br><br />
<br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1572Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:36:22Z<p>Gillian Air: /* Knockout mouse lines */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
Recepto[http://www.example.com link title]rs for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
No experiments have been published using glycosyltransferase knockout mice.<br />
<br><br />
<br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1571Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:35:02Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
Recepto[http://www.example.com link title]rs for hPIV3 are located in the human respiratory tract. Glycan profiling of human lung tissue has been carried out by the CFG Core C [http://www.functionalglycomics.org/glycomics/publicdata/glycoprofiling-new.jsp].<br />
<br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1570Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:30:00Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI along with fucosyl transferases that generate Sialyl-Lewis x.<br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=1569Parainfluenza virus type 3 hemagglutinin-neuraminidase2011-04-13T04:16:57Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>Human parainfluenza viruses (HPIVs) are a group of respiratory viruses associated with human respiratory diseases including bronchitis, bronchiolitis, and pneumonia<ref>Moscona, A. 2005. Entry of parainfluenza virus into cells as a target for interrupting childhood respiratory disease. J Clin Invest 115(7):1688-98.</ref><ref>Sato, M. and P.F. 2008. Current status of vaccines for parainfluenza virus infections. Pediatr Infect Dis J 27(10 Suppl):S123-5.</ref><ref>Johnstone, J., S.R. Majumdar, J.D. Fox, and T.J. Marrie. 2008. Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation. Chest 134(6):1141-8.</ref>. Paramyxoviruses, including HPIVs, possess an envelope protein hemagglutinin-neuraminidase (HN) that has receptor-cleaving as well as receptor-binding activity where the two activities reside on the same glycoprotein unlike influenza which carries hemagglutinin and neuraminidase activities as individual glycoproteins. HN is also essential for activating the fusion protein (F) to mediate merger of the viral envelope with the host cell membrane <ref name="Lamb1993">Lamb, R. 1993. Paramyxovirus fusion: A hypothesis for changes. Virology 197:1-11.</ref><ref name="Iorio2009">Iorio, R.M., V.R. Melanson, and P.J. Mahon. 2009. Glycoprotein interactions in paramyxovirus fusion. Future Virol 4(4):335-351.</ref>. For the parainfluenza viruses as well as other HN-containing paramyxoviruses, this single molecule carries out three different but critical activities at specific points in the process of viral entry. The first step in infection by HPIV is binding to the lung cells’ surface via interaction of the viral receptor-binding molecule with sialic acid-containing receptor molecules on the cell surface <ref name="Suzuki2001">Suzuki, T., A. Portner, R.A. Scroggs, M. Uchikawa, N. Koyama, et al. 2001. Receptor specificities of human respiroviruses. J Virol 75(10):4604-13.</ref><ref name="Moscona2010">Moscona, A., M. Porotto, S. Palmer, C. Tai, L. Aschenbrenner, et al. 2010. A Recombinant Sialidase Fusion Protein Effectively Inhibits Human Parainfluenza Viral Infection In Vitro and In Vivo. J Infect Dis.</ref>.<br />
Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus (NDV), HPIV type 3, and HPIV type 5 (formerly called SV5). Determination of the HN structure of hPIV3 (globular domain) show an enzyme active site very similar to that of influenza neuraminidase and PIV5 HN and this appears to also be a binding site. A second site at the dimer interface has been crystallographically determined only for Newcastle Disease virus (NDV) HN, but a rising number of reports postulate the presence of such a second site for other paramyxoviruses <ref>Zaitsev, V., M. von Itzstein, D. Groves, M. Kiefel, T. Takimoto, et al. 2004. Second sialic acid binding site in newcastle disease virus hemagglutinin-neuraminidase: implications for fusion. J Virol 78(7):3733-41.</ref><ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref><ref>Yuan, P., T.B. Thompson, B.A. Wurzburg, R.G. Paterson, R.A. Lamb, et al. 2005. Structural studies of the parainfluenza virus 5 hemagglutinin-neuraminidase tetramer in complex with its receptor, sialyllactose. Structure 13(5):803-15.</ref><ref>Lamb, R.A., R.G. Paterson, and T.S. Jardetzky. 2005. Paramyxovirus membrane fusion: lessons from the F and HN atomic structures. Virology 344(1):30-7.</ref><ref>Bousse, T. and T. Takimoto. 2006. Mutation at residue 523 creates a second receptor binding site on human parainfluenza virus type 1 hemagglutinin-neuraminidase protein. J Virol 80(18):9009-16.</ref><ref>Porotto, M., M. Fornabaio, G. Kellogg, and A. Moscona. 2007. A second receptor binding site on the human parainfluenza 3 hemagglutinin-neuraminidase contributes to activation of the fusion mechanism. J Virol 81(7):3216-3228.</ref>. Interestingly for NDV HN, functional analysis of the two sites indicated that engagement of the first site activates the second <ref>Porotto, M., M. Fornabaio, O. Greengard, M.T. Murrell, G.E. Kellogg, et al. 2006. Paramyxovirus receptor-binding molecules: engagement of one site on the hemagglutinin-neuraminidase protein modulates activity at the second site. J Virol 80(3):1204-13.</ref><ref>Ryan, C., V. Zaitsev, D.J. Tindal, J.C. Dyason, R.J. Thomson, et al. 2006. Structural analysis of a designed inhibitor complexed with the hemagglutinin-neuraminidase of Newcastle disease virus. Glycoconj J 23(1-2):135-41.</ref>. Further studies on the relationship between the sialic acid binding and cleavage activity of wildtype and mutant HPIV HNs are ongoing among CFG PIs. A region next to the transmembrane domain of HN (stalk region) is still elusive to crystal determination, however several studies showed the importance of this domain in fusion promotion <ref>Melanson, V.R. and R.M. Iorio. 2004. Amino acid substitutions in the F-specific domain in the stalk of the newcastle disease virus HN protein modulate fusion and interfere with its interaction with the F protein. J Virol 78(23):13053-61.</ref><ref>Melanson, V.R. and R.M. Iorio. 2006. Addition of N-glycans in the stalk of the Newcastle disease virus HN protein blocks its interaction with the F protein and prevents fusion. J Virol 80(2):623-33.</ref><ref>Porotto, M., M. Murrell, O. Greengard, and A. Moscona. 2003. Triggering of human parainfluenza virus 3 fusion protein(F) by the hemagglutinin-neuraminidase (HN): an HN mutation diminishing the rate of F activation and fusion. J Virol 77(6):3647-3654.</ref><ref>Bishop, K.A., A.C. Hickey, D. Khetawat, J.R. Patch, K.N. Bossart, et al. 2008. Residues in the stalk domain of the hendra virus g glycoprotein modulate conformational changes associated with receptor binding. J Virol 82(22):11398-409.</ref>.<br />
<br />
To further emphasize the importance of understanding GBP paradigms, CFG PIs have shown that HPIV3 infection in cultured monolayer cells greatly differs from infection in human airway epithelial (HAE) cell cultures or in animal models <ref>Zhang, L., M.E. Peeples, R.C. Boucher, P.L. Collins, and R.J. Pickles. 2002. Respiratory syncytial virus infection of human airway epithelial cells is polarized, specific to ciliated cells, and without obvious cytopathology. J Virol 76(11):5654-66.</ref><ref>Mellow, T.E., P.C. Murphy, J.L. Carson, T.L. Noah, L. Zhang, et al. 2004. The effect of respiratory synctial virus on chemokine release by differentiated airway epithelium. Exp Lung Res 30(1):43-57.</ref><ref>Zhang, L., A. Bukreyev, C.I. Thompson, B. Watson, M.E. Peeples, et al. 2005. Infection of ciliated cells by human parainfluenza virus type 3 in an in vitro model of human airway epithelium. J Virol 79(2):1113-24.</ref><ref>Thompson, C.I., W.S. Barclay, M.C. Zambon, and R.J. Pickles. 2006. Infection of human airway epithelium by human and avian strains of influenza A virus. J Virol 80(16):8060-8.</ref>. HPIV3 with a single amino acid mutation in the HN glycoprotein with better than wildtype growth in cell culture had a disadvantage in an ex vivo or in vivo system, revealing a gap in our understanding of the biology of these viruses in their natural host <ref>Palermo, L., M. Porotto, C. Yokoyama, S. Palmer, B. Mungall, et al. 2009. Human parainfluenza virus infection of the airway epithelium: the viral hemagglutinin-neuraminidase regulates fusion protein activation and modulates infectivity. J Virol 83(13):6900-6908.</ref>. This suggests that even slight variations in receptor types may influence HPIV infectivity. Recently a series of studies using glycoarray analysis started to navigate the complexity of the interaction between these viruses and glycomolecules <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref>. The three functions of HN depend upon interaction with glycomolecules, therefore understanding whether glycomolecules are preferentially bound, cleave, or activate the fusion process will unravel the biology of these viruses and will help in developing targeted antivirals.<br />
<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., D.F. Smith, R.D. Cummings, and G.M. Air. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with alpha2-3-linked sialic acids that are distinct from those bound by H5 avian influenza virus hemagglutinin. J Virol 81(15):8341-5.</ref><br />
<br>[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by HPIV paramyxoviruses that bind to sialic acid-containing receptor molecules on the surface of host lung cells.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
The parainfluenza viruses type 3 ligands are typical of complex N-linked glycans. The sialyltransferases that generate the PIV3 receptors are ST3GalIII, ST3GalIV, ST3GalVI.<br />
<br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref>Lawrence, M.C., N.A. Borg, V.A. Streltsov, P.A. Pilling, V.C. Epa, et al. 2004. Structure of the Haemagglutinin-neuraminidase from Human Parainfluenza Virus Type III. J Mol Biol 335(5):1343-57.</ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
hPIV HN plays important roles in several distinct steps associated with viral entry, which causes human respiratory infections. For the parainfluenza viruses as well as other paramyxoviruses that utilize hemagglutinin-neuraminidases, the HN protein carries out three different activities in the process of viral entry and release: (1) The first step in infection by human parainfluenza virus is binding to the lung cell surface via interaction of HN with sialic acid-containing receptor molecules on the cell surface.<ref name="Suzuki2001"/><ref name="Moscona2010"/> (2) HN is also essential for activating the fusion protein to mediate merger of the viral envelope with the host cell membrane.<ref name="Lamb1993"/><ref name="Iorio2009"/> (3) Finally, the neuraminidase activity of HN is required for release of the virus from cells.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
hPIV HN is not represented on the CFG microarrays, which only contain probes for mouse and human glycogenes.<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase (for example, click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490 here]). To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto<br />
<br />
[[Category:Introduction]]</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1568Influenza hemagglutinin H32011-04-13T04:12:22Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]). The sialyltransferases that generate ligands for most H3 subtype hemagglutinins are ST6Gal1, ST6GalII, ST6GalNAc1, ST6GalNAcII, ST6GalNAcIV.<br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1566Influenza hemagglutinin H32011-04-09T21:48:59Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
Sialylated glycoproteins or glycolipids recognized by human influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but with rare exceptions the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]).<br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=1565Influenza hemagglutinin H32011-04-09T21:46:37Z<p>Gillian Air: /* Biosynthesis of ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s, the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal, while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments, they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools, such as the glycam microarray, provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 as well as other influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure so far of H5N1 to be established in the human population, whereas swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the precise rules may differ. Hoever, much progress had been made in the CFG with participating investiigators of understanding the receptor specificity and transmissability of H1 and H2 subypes. Fortunately, the H5N1 avian virus has still not acquired the ability to transmit between humans, as the rules seem more complex compared to H1, H2 and H3, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Glycan array analyses indicate that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref>.<br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
Sialylated glycoproteins or glycolipids recognized by influenza hemagglutinin H3 are synthesized by host cells. The H3 hemagglutinin shows considerable diversity in binding but almost always the sialic acid is attached 2-6 to the next sugar on structures that are mostly typical of N-linked glycans on proteins. The enzymes required for biosynthesis of the type 2 poly N-acetyllactosamine chains and modification with sialic acid or with sialic acid and fucose, have been defined ([http://www.functionalglycomics.org/glycomics/molecule/jsp/glycoEnzyme/geMolecule.jsp?slideNumber=slide7][poly N-acetyllactosamine extension biosynthesis]).<br />
<br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. However, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array (click [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 here] for example), and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species. CFG data for many of these subtypes are available in the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin."]<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Ian Wilson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=910Parainfluenza virus type 3 hemagglutinin-neuraminidase2010-07-06T06:46:06Z<p>Gillian Air: /* Glycan array */</p>
<hr />
<div>Like influenza, the paramyxoviruses show hemagglutinin and neuraminidase (HN) activities, but in this case, the two activities reside on the same glycoprotein. Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus, human parainfluenza type 3, and human parainfluenza type 5 (formerly called SV5). The structures show an identical fold to influenza neuraminidase, with an NA active site that is almost identical to that of influenza. Thus HN is a sialidase that also binds sialylated glycans as receptors for cell entry. Whether there is a separate binding site has been a subject of great controversy that is still not solved. NDV shows sialic acid bound at a second site but the second molecule has not been seen in hPIV3 or hPIV5 HN structures. Mutagenesis and antibody studies suggest one site in some strains and two sites in others, while a second site appeared to be created in hPIV3 by mutagenesis. This lack of understanding of how paramyoviruses enter cells and how new viruses are released has severely hampered development to antivirals targeted to these activities. CFG PIs are investigating the binding and cleavage specificities of HNs and mutants.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifdications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., Smith, D.F., Cummings, R.D., and Air, G.M. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with {alpha}2-3 linked sialic acid that are distinct from those bound by H5 avian influenza hemagglutinin. J Virol 81:8341-8345.</ref><br />
<br><br />
[[File: PIV3glycans.png]]<br />
[[Media:Example.ogg]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by paramyxoviruses.<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref> Lawrence MC, Borg NA, Streltsov VA, Pilling PA, Epa VC, Varghese JN, McKimm-Breschkin JL, Colman PM. (2004) Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III. J Mol Biol 335(5): 1343-57. </ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490]. To see all glycan array results for parainfluenza hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=parainfluenza&cat=coreh here]. For glycan array results of other paramyxovirus HNs, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites.<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=909Parainfluenza virus type 3 hemagglutinin-neuraminidase2010-07-06T06:40:44Z<p>Gillian Air: /* Carbohydrate ligands */</p>
<hr />
<div>Like influenza, the paramyxoviruses show hemagglutinin and neuraminidase (HN) activities, but in this case, the two activities reside on the same glycoprotein. Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus, human parainfluenza type 3, and human parainfluenza type 5 (formerly called SV5). The structures show an identical fold to influenza neuraminidase, with an NA active site that is almost identical to that of influenza. Thus HN is a sialidase that also binds sialylated glycans as receptors for cell entry. Whether there is a separate binding site has been a subject of great controversy that is still not solved. NDV shows sialic acid bound at a second site but the second molecule has not been seen in hPIV3 or hPIV5 HN structures. Mutagenesis and antibody studies suggest one site in some strains and two sites in others, while a second site appeared to be created in hPIV3 by mutagenesis. This lack of understanding of how paramyoviruses enter cells and how new viruses are released has severely hampered development to antivirals targeted to these activities. CFG PIs are investigating the binding and cleavage specificities of HNs and mutants.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans. The sialic acid is linked &alpha;2-3 to galactose. The minimal binding motif is a pentasaccharide if there are no modifdications, but smaller units bind if there is sulfation or fucosylation, as shown in the figure below <ref>Amonsen, M., Smith, D.F., Cummings, R.D., and Air, G.M. 2007. Human parainfluenza viruses hPIV1 and hPIV3 bind oligosaccharides with {alpha}2-3 linked sialic acid that are distinct from those bound by H5 avian influenza hemagglutinin. J Virol 81:8341-8345.</ref><br />
<br><br />
[[File: PIV3glycans.png]]<br />
[[Media:Example.ogg]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by paramyxoviruses.<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref> Lawrence MC, Borg NA, Streltsov VA, Pilling PA, Epa VC, Varghese JN, McKimm-Breschkin JL, Colman PM. (2004) Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III. J Mol Biol 335(5): 1343-57. </ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490]. To see all glycan array results for paramyxovirus hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites.<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=908Parainfluenza virus type 3 hemagglutinin-neuraminidase2010-07-06T06:28:05Z<p>Gillian Air: /* Carbohydrate ligands */</p>
<hr />
<div>Like influenza, the paramyxoviruses show hemagglutinin and neuraminidase (HN) activities, but in this case, the two activities reside on the same glycoprotein. Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus, human parainfluenza type 3, and human parainfluenza type 5 (formerly called SV5). The structures show an identical fold to influenza neuraminidase, with an NA active site that is almost identical to that of influenza. Thus HN is a sialidase that also binds sialylated glycans as receptors for cell entry. Whether there is a separate binding site has been a subject of great controversy that is still not solved. NDV shows sialic acid bound at a second site but the second molecule has not been seen in hPIV3 or hPIV5 HN structures. Mutagenesis and antibody studies suggest one site in some strains and two sites in others, while a second site appeared to be created in hPIV3 by mutagenesis. This lack of understanding of how paramyoviruses enter cells and how new viruses are released has severely hampered development to antivirals targeted to these activities. CFG PIs are investigating the binding and cleavage specificities of HNs and mutants.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans.<br />
<br><br />
[[File: PIV3glycans.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by paramyxoviruses.<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref> Lawrence MC, Borg NA, Streltsov VA, Pilling PA, Epa VC, Varghese JN, McKimm-Breschkin JL, Colman PM. (2004) Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III. J Mol Biol 335(5): 1343-57. </ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490]. To see all glycan array results for paramyxovirus hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites.<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:PIV3glycans.png&diff=907File:PIV3glycans.png2010-07-06T06:25:01Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=906Parainfluenza virus type 3 hemagglutinin-neuraminidase2010-07-04T05:27:48Z<p>Gillian Air: /* Structure */</p>
<hr />
<div>Like influenza, the paramyxoviruses show hemagglutinin and neuraminidase (HN) activities, but in this case, the two activities reside on the same glycoprotein. Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus, human parainfluenza type 3, and human parainfluenza type 5 (formerly called SV5). The structures show an identical fold to influenza neuraminidase, with an NA active site that is almost identical to that of influenza. Thus HN is a sialidase that also binds sialylated glycans as receptors for cell entry. Whether there is a separate binding site has been a subject of great controversy that is still not solved. NDV shows sialic acid bound at a second site but the second molecule has not been seen in hPIV3 or hPIV5 HN structures. Mutagenesis and antibody studies suggest one site in some strains and two sites in others, while a second site appeared to be created in hPIV3 by mutagenesis. This lack of understanding of how paramyoviruses enter cells and how new viruses are released has severely hampered development to antivirals targeted to these activities. CFG PIs are investigating the binding and cleavage specificities of HNs and mutants.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans.<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by paramyxoviruses.<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref> Lawrence MC, Borg NA, Streltsov VA, Pilling PA, Epa VC, Varghese JN, McKimm-Breschkin JL, Colman PM. (2004) Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III. J Mol Biol 335(5): 1343-57. </ref> and serves as the model for glycan binding and neuraminidase studies.<br />
<br><br />
The subunits are colored green and blue. A molecule of inhibitor 2-deoxy-2,3-dehydro-N-acetyl-neuraminic acid is bound to the active site of each subunit (stick model: C, O and N atoms are gray, red and blue respectively). The figure was made using PyMol (Delano Scientific) from PDB file 1V3D.<br />
<br><br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490]. To see all glycan array results for paramyxovirus hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites.<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Parainfluenza_virus_type_3_hemagglutinin-neuraminidase&diff=905Parainfluenza virus type 3 hemagglutinin-neuraminidase2010-07-04T05:23:06Z<p>Gillian Air: /* Structure */</p>
<hr />
<div>Like influenza, the paramyxoviruses show hemagglutinin and neuraminidase (HN) activities, but in this case, the two activities reside on the same glycoprotein. Structures of three paramyxovirus HNs have been determined; they are Newcastle Disease virus, human parainfluenza type 3, and human parainfluenza type 5 (formerly called SV5). The structures show an identical fold to influenza neuraminidase, with an NA active site that is almost identical to that of influenza. Thus HN is a sialidase that also binds sialylated glycans as receptors for cell entry. Whether there is a separate binding site has been a subject of great controversy that is still not solved. NDV shows sialic acid bound at a second site but the second molecule has not been seen in hPIV3 or hPIV5 HN structures. Mutagenesis and antibody studies suggest one site in some strains and two sites in others, while a second site appeared to be created in hPIV3 by mutagenesis. This lack of understanding of how paramyoviruses enter cells and how new viruses are released has severely hampered development to antivirals targeted to these activities. CFG PIs are investigating the binding and cleavage specificities of HNs and mutants.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of parainfluenza virus type 3 HN include: Gillian Air, Theodore Jardetsky, Matteo Porotto, Charles Russell<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase binds sialylated glycans.<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
<br />
Parainfluenza virus type 3 hemagglutinin-neuraminidase is expressed by paramyxoviruses.<br />
=== Biosynthesis of ligands ===<br />
<br />
<br><br />
=== Structure ===<br />
The crystal structure of a hPIV3 HN has been determined in dimer form <ref> Lawrence MC, Borg NA, Streltsov VA, Pilling PA, Epa VC, Varghese JN, McKimm-Breschkin JL, Colman PM. (2004) Structure of the haemagglutinin-neuraminidase from human parainfluenza virus type III. J Mol Biol 335(5): 1343-57. </ref><br />
<br><br />
<br />
[[file: 1V3D.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=parainfluenza&maxresults=20 CFG database search results for "parainfluenza"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
There have been many resource requests for glycan array screening of paramyxovirus hemagglutinin-neuraminidase [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_2490]. To see all glycan array results for paramyxovirus hemagglutinin-neuraminidase, click [http://www.functionalglycomics.org/glycomics/search/jsp/result.jsp?query=paramyxovirus&cat=coreh here].<br />
<br />
== Related GBPs ==<br />
* Other paramyxovirus HNs: some appear to have one site that carries out both activities; others appear to have separate sites.<br />
* Human parainfluenza types 1, 2, 4 and 5<br />
* Newcastle Disease virus<br />
* Mumps virus<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson, Matteo Porotto</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:1V3D.png&diff=904File:1V3D.png2010-07-04T05:19:03Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=903Influenza hemagglutinin H32010-07-04T05:16:12Z<p>Gillian Air: /* Structure */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref>. <br><br />
The image of the HA trimer was made with PyMol (Delano Scientific) from PDB file 5HMG. The three subunits are colored green, blue and magenta. For each, the darker shade is the HA1 polypeptide and the lighter shade is HA2.<br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. HOwever, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 example], and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=902Influenza hemagglutinin H32010-07-04T05:11:55Z<p>Gillian Air: /* Structure */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:5HMGlow.png]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. HOwever, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 example], and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:5HMGlow.png&diff=901File:5HMGlow.png2010-07-04T05:10:28Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:5HMG.png&diff=900File:5HMG.png2010-07-04T04:58:43Z<p>Gillian Air: Structure of the H3 trimer. The image was made with PyMol (DeLano Scientific)using PDB file 5HMG. The three monmoers are colored green, blue and magenta.For each, the darker color is the HA1 polypeptide and the lighter shade is HA2.</p>
<hr />
<div>Structure of the H3 trimer. The image was made with PyMol (DeLano Scientific)using PDB file 5HMG. The three monmoers are colored green, blue and magenta.For each, the darker color is the HA1 polypeptide and the lighter shade is HA2.</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=899Influenza hemagglutinin H32010-07-04T04:49:14Z<p>Gillian Air: /* Structure */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars.<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br />
=== Cellular expression of GBP and ligands ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br />
=== Biosynthesis of ligands ===<br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:5HMGjpg.pdf]]<br />
<br><br />
<br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. HOwever, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array [http://www.functionalglycomics.org/glycomics/HServlet?operation=view&sideMenu=no&psId=primscreen_PA_v1_260_12072005 example], and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:5HMGjpg.pdf&diff=898File:5HMGjpg.pdf2010-07-04T04:45:56Z<p>Gillian Air: Structure of the trimer of H3 HA (A/Aichi X-31/68). The image was made using PyMol (Delano Scientific) from PDB file 5HMG. The monomers are colored green, blue and magenta. The darker shade for each is the HA1 polypeptide; the lighter shade is HA2.</p>
<hr />
<div>Structure of the trimer of H3 HA (A/Aichi X-31/68). The image was made using PyMol (Delano Scientific) from PDB file 5HMG. The monomers are colored green, blue and magenta. The darker shade for each is the HA1 polypeptide; the lighter shade is HA2.</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:5HMG.jpg&diff=897File:5HMG.jpg2010-07-04T04:40:07Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=754Influenza hemagglutinin H32010-06-15T23:02:17Z<p>Gillian Air: /* Knockout mouse lines */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease. HOwever, studies were done using a mouse-adapted virus <ref> Glaser L, Conenello G, Paulson J, Palese P. Effective replication of human influenza viruses in mice lacking a major alpha2,6 sialyltransferase. Virus Res. 2007 Jun;126(1-2):9-18.</ref><br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><ref><br />
,<br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=753Influenza hemagglutinin H32010-06-15T22:58:15Z<p>Gillian Air: /* Glycan array */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease.<br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03),<br />
Steinhauer (#1777; A/Aichi/68 and mutants),<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97),<br />
Rottier (#1797, A/Finland),<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82),<br />
Chen (#1468; A/Victoria/75),<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003),<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<ref>Stevens, J., Blixt, O., Chen, L. M., Donis, R. O., Paulson, J. C., and Wilson, I. A. (2008). Recent avian H5N1 viruses exhibit increased propensity for acquiring human receptor specificity. J Mol Biol 381(5), 1382-94.</ref><ref><br />
Stevens, J., Blixt, O., Glaser, L., Taubenberger, J. K., Palese, P., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray analysis of the hemagglutinins from modern and pandemic influenza viruses reveals different receptor specificities. J Mol Biol 355(5), 1143-55.</ref><ref><br />
Stevens, J., Blixt, O., Paulson, J. C., and Wilson, I. A. (2006). Glycan microarray technologies: tools to survey host specificity of influenza viruses. Nat Rev Microbiol 4(11), 857-64.</ref><ref><br />
Stevens, J., Blixt, O., Tumpey, T. M., Taubenberger, J. K., Paulson, J. C., and Wilson, I. A. (2006). Structure and receptor specificity of the hemagglutinin from an H5N1 influenza virus. Science 312(5772), 404-10.</ref><ref><br />
,<br />
<br><br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=752Influenza hemagglutinin H32010-06-15T22:24:21Z<p>Gillian Air: /* Glycan array */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease.<br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database. Glycan Array analyses of H3 HAs have been run for the following PI's:<br><br />
Compans (Resource Request #1781; A/Aichi/1/68, A/Udorn/72 and A/Wyoming/3/03)<br />
Steinhauer (#1777; A/Aichi/68 and mutants)<br />
Olsen (#1796, A/swine/Mn/593/99 and A/swine/Ontario/130/97)<br />
Rottier (#1797, A/Finland)<br />
Air (#1660, 1380, 1033, 948, 175; A/Oklahoma/483/2008, A/OK/309/06, A/Oklahoma/323/2003, A/OK/370/05, A/OK/369/05, A/OK/1992/05, A/Wyoming/3/03, A/Philippines/82)<br />
Chen (#1468; A/Victoria/75)<br />
Donis (#138; A/canine/Florida/2004, A/equine/MA/2003)<br />
Paulson (#451; duck/Ukraine/63, A/Moscow/10/99)<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=751Influenza hemagglutinin H32010-06-15T19:02:48Z<p>Gillian Air: /* Glycogene microarray */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
There are no glycogene array results with the H3 HA, but related paradigm H1 HA has been used by Dr Linda Sherman to assess the role of protein glycosylation in the decision between deletion vs. anergy in immune tolerance. The antigen used was a peptide of A/PR/8/34 (H1N1) HA, 518-IYSTVASSL-526. CFG Request #1155<br />
<br><br />
<br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease.<br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=624Influenza hemagglutinin H32010-06-13T05:39:43Z<p>Gillian Air: /* Glycan array */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease.<br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators' laboratories. In addition, the CFG glycan array library has been used print custom sialic acid glycan arrays for the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=623Influenza hemagglutinin H32010-06-13T05:37:40Z<p>Gillian Air: /* Knockout mouse lines */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
Unfortunately the mouse is a very poor model of influenza infection. Some viruses with H3 HA infect mice quite readily, but do not cause a human-like disease. This means that studies of infection and transmission of H3N2 influenza viruses in SiaT knockout mice are difficult to translate to the human disease.<br />
<br><br />
<br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=622Influenza hemagglutinin H32010-06-13T05:31:49Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results <ref>Nicholls JM, Chan RW, Russell RJ, Air GM, Peiris JS. Evolving complexities of influenza virus and its receptors. Trends Microbiol 2008 2008 Apr;16(4):149-57.</ref>. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=621Influenza hemagglutinin H32010-06-13T05:29:00Z<p>Gillian Air: /* Glycan profiling */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
Virologists have used lectin binding to try to determine where the influenza virus receptors specific for human or avian HAs are located in the human respiratory tract, with mixed results. A complete profile of human trachea as well as lung is needed.<br />
<br><br />
<br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=620Influenza hemagglutinin H32010-06-13T05:22:39Z<p>Gillian Air: /* Carbohydrate ligands */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtype H3N2) binds to N-acetylneuraminic acid linked &alpha;2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
<br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=619Influenza hemagglutinin H32010-06-13T05:21:14Z<p>Gillian Air: /* Biological roles of GBP-ligand interaction */</p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
Sialylated glycans on the surface of cells lining the respiratory tract serve to capture virus to initiate infection. Glycan array analyses have confirmed that human influenza viruses such as those carrying the H3 HA bind only to structures with NeuAc&alpha;2-6 and avian isolates bind only to structures containing NeuAc&alpha;2-3. The role of this GBP-glycan interaction in initiating endocytosis and replication is still unclear.<br />
<br><br />
<br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=618Influenza hemagglutinin H32010-06-13T05:10:17Z<p>Gillian Air: </p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
[[File:H3binding2.png]]<br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:H3binding2.png&diff=617File:H3binding2.png2010-06-13T05:08:49Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:H3binding.png&diff=616File:H3binding.png2010-06-13T04:30:15Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=615Influenza hemagglutinin H32010-06-13T04:27:07Z<p>Gillian Air: </p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
<br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
[[File:H3structure.png]]<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=614Influenza hemagglutinin H32010-06-13T04:25:23Z<p>Gillian Air: </p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
<br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
The crystal structure of H3 HA was determined by Wilson, Wiley & Skehel in 1981. This has served as a model for more recent HA structure determinations such as H1 HA <ref>Xu R, Ekiert DC, Krause JC, Hai R, Crowe JE, Wilson IA. Structural basis of preexisting immunity to the 2009 H1N1 pandemic influenza virus. Science 2010 Apr 16;328(5976):357-60.</ref><br />
<br><br />
<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:H3structure.png&diff=613File:H3structure.png2010-06-13T04:18:39Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=612Influenza hemagglutinin H32010-06-13T03:28:45Z<p>Gillian Air: </p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
<br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:H3_binding.jpg&diff=611File:H3 binding.jpg2010-06-13T03:18:19Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=File:H3_binding_specificity.jpg&diff=610File:H3 binding specificity.jpg2010-06-13T03:14:17Z<p>Gillian Air: </p>
<hr />
<div></div>Gillian Airhttps://glycan.mit.edu/CFGparadigms/index.php?title=Influenza_hemagglutinin_H3&diff=609Influenza hemagglutinin H32010-06-13T03:04:05Z<p>Gillian Air: </p>
<hr />
<div>'''Influenza hemagglutinin (H3 serotype)''' was the first glycoprotein structure to be solved at atomic resolution, by Ian Wilson, John Skehel and Don Wiley in 1981. The collaboration between the Skehel and Wiley labs provided great insight into hemagglutinin function, and it remains the prototype for understanding receptor recognition, antigenic variation, and the extraordinary conformational changes associated with target membrane insertion and ultimately fusion of viral with cell membrane to allow the viral genome to enter the cell and replicate.<br />
<br />
In the 1980s the Paulson lab made the seminal discovery that human and avian viruses with the H3 serotype have different receptor specificities; that human viruses bind to Neu5Acα2-6Gal while avian viruses bind Neu5Acα2-3Gal. In two very elegant experiments they were able to switch these specificities by applying selective pressure, and showed that a single amino acid change (L226Q) was all that was required for early H3N2 viruses to switch between human and avian specificities.<br />
These results showed how easy it can be for avian viruses to cross the species barrier into humans. Seasonal influenza viruses with the H3 serotype continue to circulate in the human<br />
population, and subtleties in their receptor specificities appear to be playing a role in how clinical isolates can be recovered in laboratory hosts. CFG investigators are using tools provided by the CFG to analyze the detailed receptor specificity of the circulating H3N2 influenza viruses and their interaction with laboratory hosts to better understand this phenomenon, which has direct consequences on production of vaccines.<br />
<br />
Although the influenza H3 hemagglutinin has been chosen as the paradigm, since so much is known, there are 16 subtypes of influenza HA (H1-H16), defined by lack of antigenic cross-reactivity. There is typically only about 20% amino acid sequence identity between HAs of different subtypes. There are interesting and important differences in how easily a particular strain within the subtype can change its binding specificity between avian-like and human-like receptors, leading to the failure of H5N1 to be established in the human population while swine-origin H1N1 showed high transmissibility between humans from the time it was first isolated.<br />
<br />
To understand the transmission of influenza viruses and how new pandemics begin, it will be important to study a variety of HA subtypes and strains. but for other subtypes the rules are different and are not yet understood. The H5N1 avian virus has still not acquired the ability to transmit between humans, despite at least 15 years of opportunity. The CFG has facilitated considerable advances in our knowledge of the role of sialic acid binding in influenza host specificity and tropism for the upper or lower respiratory tract, and these studies need to be continued until we understand how influenza viruses enter the human population to cause each new pandemic, and the role of receptor specificity in pathogenicity.<br />
<br />
== CFG Participating Investigators contributing to the understanding of this paradigm ==<br />
CFG Participating Investigators (PIs) contributing to the understanding of H3 include: Gillian Air, Rafi Ahmed, Nicolai Bovin, Ruben Donis, Chwan-Chuen King, Vladimir Lugovtsev, Christopher Olsen, Peter Palese, James Paulson, Andrew Pekosz, Daniel Perez, Peter P.J.M. Rottier, Charles Russell, Ram Sasisekharan, Dorothy Scott, David Smith, James Stevens, Stephen Mark Tompkins, Reinhard Vlasak, Qinghua Wang, Ian Wilson<br />
<br />
== Progress toward understanding this GBP paradigm ==<br />
<br />
=== Carbohydrate ligands ===<br />
Ligands for H3 hemagglutinin are sialylated glycans. The H3 hemagglutinin of human viruses (subtypeH3N2) binds to N-acetylneuraminic acid linked &alpha2-6 to galactose, sometimes N-acetylgalactosamine. Recent human H3 HAs have shown variation in their specificity of binding downstream sugars<ref>Gulati S, Smith DF, Air GM. Deletions of neuraminidase and resistance to oseltamivir may be a consequence of restricted receptor specificity in recent H3N2 influenza viruses. Virology J 2009;6(22).</ref><br />
<br><br />
=== Cellular expression ===<br />
HA is expressed on the surface of influenza virus infected cells before being budded out into progeny virions. H3N2 viruses infect the respiratory tract of humans and birds; in birds they may also infect the gut epithelia. H3N2 viruses infect very few continuous cell lines. Madin-Darby canine kidney cells are most commonly used. Non-permissive cell lines may take up virus efficiently, replicate RNA and express HA on the cell surface but do not bud new virus particles <ref>Kumari K, Gulati S, Smith DF, Gulati U, Cummings RD, Air GM. Receptor binding specificity of recent human H3N2 influenza viruses. Virol J 2007;4(42):1-12.</ref><br />
<br><br />
=== Structure ===<br />
<br />
<br><br />
=== Biological roles of GBP-ligand interaction ===<br />
<br />
<br><br />
== CFG resources used in investigations ==<br />
The best examples of CFG contributions to this paradigm are described below, with links to specific data sets. For a complete list of CFG data and resources relating to this paradigm, see the [http://www.functionalglycomics.org/glycomics/search/jsp/landing.jsp?query=hemagglutinin&maxresults=20 CFG database search results for "hemagglutinin"].<br />
<br />
=== Glycan profiling ===<br />
<br />
<br><br />
=== Glycogene microarray ===<br />
<br />
<br><br />
=== Knockout mouse lines ===<br />
<br />
<br><br />
=== Glycan array ===<br />
The majority of PI-initiated requests for CFG resources to study influenza have been requests for analysis of receptor specificity on the glycan array, and the remainder have been requests for compounds to conduct ''in vitro'' assays in investigators laboratories. In addition, the CFG glycan array library has been used for custom sialic acid glycan array to the U.S. Centers for Disease Control (CDC) for analysis of the receptor specificity of emerging viruses, with data deposited to the CFG database.<br />
<br />
== Related GBPs ==<br />
Influenza virus HAs of other serotype H1, H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15, H16 and type B. Type A subtypes H1, H2, H5, H6, H7, and H9 are all being actively investigated by CFG investigators for their potential to jump to humans and type B for its failure to spread in non-human species.<br />
<br />
== References ==<br />
<references/><br />
<br />
== Acknowledgements ==<br />
The CFG is grateful to the following PIs for their contributions to this wiki page: Gillian Air, James Paulson</div>Gillian Air