Galectin-9 - Revision history

Anna Crie at 01:05, 22 January 2012

2012-01-22T01:05:38Z

Anna Crie at 01:05, 22 January 2012

2012-01-22T01:05:05Z

Anna Crie at 01:02, 22 January 2012

2012-01-22T01:02:49Z

Anna Crie: /* Biological roles of GBP-ligand interaction */

2012-01-22T00:46:44Z

Biological roles of GBP-ligand interaction

Anna Crie: /* Structure */

2012-01-22T00:30:14Z

Structure

Anna Crie: /* Cellular expression of GBP and ligands */

2012-01-22T00:19:46Z

Cellular expression of GBP and ligands

Anna Crie: /* Carbohydrate ligands */

2012-01-22T00:15:42Z

Carbohydrate ligands

Anna Crie at 00:04, 22 January 2012

2012-01-22T00:04:56Z

Anna Crie: /* Structure */

2012-01-21T23:59:05Z

Structure

Anna Crie: /* Cellular expression of GBP and ligands */

2012-01-21T23:49:57Z

Cellular expression of GBP and ligands

← Older revision		Revision as of 01:05, 22 January 2012
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−	Galectin-9 is one of the best-studied of the tandem-repeat galectins with glycan binding in both the N- and C-terminal domains <ref name="Wada 1997">Wada J, Kanwar YS. Identification and characterization of galectin-9, a novel beta-galactoside-binding mammalian lectin. J Biol Chem. 1997;272(9):6078-86</ref>. The protein lacks a signal sequence, like most galectins, and is synthesized in the cytosol on free polyribosomes. Galectin-9 is found outside of cells and may be exported by non-classical pathways. Galectin-9 exhibits a variety of biological activities, the majority of which have focused on its immunomodulatory role toward lymphocytes, were it shows specific interactions with TIM-3, and can negatively regulate Th1 type immunity<ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref>. Mammalian galectin-9 exhibits affinity toward select glycan ligands, including sulfated glycans, and blood group-related glycans, and also interacts with glycans containing poly-N-acetyllactosamine (LacNAc) repeats (-3Galβ1-4GlcNAcβ1-)n through recognition of internal LacNAc repeats <ref name="Nagae 2008">Nagae M, Nishi N, Nakamura-Tsuruta S, Hirabayashi J, Wakatsuki S, Kato R. Structural analysis of the human galectin-9 N-terminal carbohydrate recognition domain reveals unexpected properties that differ from the mouse orthologue. J Mol Biol. 2008;375(1):119-35</ref>).	+	Galectin-9 is one of the best-studied of the tandem-repeat galectins with glycan binding in both the N- and C-terminal domains <ref name="Wada 1997">Wada J, Kanwar YS. Identification and characterization of galectin-9, a novel beta-galactoside-binding mammalian lectin. J Biol Chem. 1997;272(9):6078-86</ref>. The protein lacks a signal sequence, like most galectins, and is synthesized in the cytosol on free polyribosomes. Galectin-9 is found outside of cells and may be exported by non-classical pathways. Galectin-9 exhibits a variety of biological activities, the majority of which have focused on its immunomodulatory role toward lymphocytes, were it shows specific interactions with TIM-3, and can negatively regulate Th1 type immunity<ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref>. Mammalian galectin-9 exhibits affinity toward select glycan ligands, including sulfated glycans, and blood group-related glycans, and also interacts with glycans containing poly-N-acetyllactosamine (LacNAc) repeats (-3Galβ1-4GlcNAcβ1-)n through recognition of internal LacNAc repeats <ref name="Nagae 2008">Nagae M, Nishi N, Nakamura-Tsuruta S, Hirabayashi J, Wakatsuki S, Kato R. Structural analysis of the human galectin-9 N-terminal carbohydrate recognition domain reveals unexpected properties that differ from the mouse orthologue. J Mol Biol. 2008;375(1):119-35</ref>.

	The crystal structure of the N-terminal carbohydrate recognition domain (CRD) been defined		The crystal structure of the N-terminal carbohydrate recognition domain (CRD) been defined

@@ Line 1: / Line 1: @@
-Galectin-9 is one of the best-studied of the tandem-repeat galectins with glycan binding in both the N- and C-terminal domains <ref name="Wada 1997">Wada J, Kanwar YS. Identification and characterization of galectin-9, a novel beta-galactoside-binding mammalian lectin. J Biol Chem. 1997;272(9):6078-86</ref>.  The protein lacks a signal sequence, like most galectins, and is synthesized in the cytosol on free polyribosomes.  Galectin-9 is found outside of cells and may be exported by non-classical pathways.  Galectin-9 exhibits a variety of biological activities, the majority of which have focused on its immunomodulatory role toward lymphocytes, were it shows specific interactions with TIM-3, and can negatively regulate Th1 type immunity <ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref>.  Mammalian galectin-9 exhibits affinity toward select glycan ligands, including sulfated glycans, and blood group-related glycans, and also interacts with glycans containing poly-N-acetyllactosamine (LacNAc) repeats (-3Galβ1-4GlcNAcβ1-)n through recognition of internal LacNAc repeats <ref name="Nagae 2008">Nagae M, Nishi N, Nakamura-Tsuruta S, Hirabayashi J, Wakatsuki S, Kato R. Structural analysis of the human galectin-9 N-terminal carbohydrate recognition domain reveals unexpected properties that differ from the mouse orthologue. J Mol Biol. 2008;375(1):119-35</ref>).
+Galectin-9 is one of the best-studied of the tandem-repeat galectins with glycan binding in both the N- and C-terminal domains <ref name="Wada 1997">Wada J, Kanwar YS. Identification and characterization of galectin-9, a novel beta-galactoside-binding mammalian lectin. J Biol Chem. 1997;272(9):6078-86</ref>.  The protein lacks a signal sequence, like most galectins, and is synthesized in the cytosol on free polyribosomes.  Galectin-9 is found outside of cells and may be exported by non-classical pathways.  Galectin-9 exhibits a variety of biological activities, the majority of which have focused on its immunomodulatory role toward lymphocytes, were it shows specific interactions with TIM-3, and can negatively regulate Th1 type immunity<ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref>.  Mammalian galectin-9 exhibits affinity toward select glycan ligands, including sulfated glycans, and blood group-related glycans, and also interacts with glycans containing poly-N-acetyllactosamine (LacNAc) repeats (-3Galβ1-4GlcNAcβ1-)n through recognition of internal LacNAc repeats <ref name="Nagae 2008">Nagae M, Nishi N, Nakamura-Tsuruta S, Hirabayashi J, Wakatsuki S, Kato R. Structural analysis of the human galectin-9 N-terminal carbohydrate recognition domain reveals unexpected properties that differ from the mouse orthologue. J Mol Biol. 2008;375(1):119-35</ref>).
 The crystal structure of the N-terminal carbohydrate recognition domain (CRD) been defined
-<ref name="Nagae 2008"/><ref name="Yoshida 2010">Yoshida H, Teraoka M, Nishi N, Nakakita S, Nakamura T, Hirashima M, Kamitori S. X-ray structures of human galectin-9 C-terminal domain in complexes with a biantennary oligosaccharide and sialyllactose. J Biol Chem. 2010;285(47):36969-76. </ref>
+<ref name="Nagae 2008"/><ref name="Yoshida 2010">Yoshida H, Teraoka M, Nishi N, Nakakita S, Nakamura T, Hirashima M, Kamitori S. X-ray structures of human galectin-9 C-terminal domain in complexes with a biantennary oligosaccharide and sialyllactose. J Biol Chem. 2010;285(47):36969-76. </ref><ref name="Nagae 2006">Nagae M, Nishi N, Murata T, Usui T, Nakamura T, Wakatsuki S, Kato R. Crystal structure of the galectin-9 N-terminal carbohydrate recognition domain from Mus musculus reveals the basic mechanism of carbohydrate recognition. J Biol Chem. 2006;281(47):35884-93.</ref>.  The GBP shows strong interactions in a metal-free manner with poly-N-acetyllactosamine sequences comprised of repeating (-3Galβ1-4GlcNAcβ1-)n by recognizing internal N-acetyllactosamine repeats<ref name="Nagae 2008"/>.  Generally, it binds distinct glycan ligands from [[Galectin-1]]<ref name="Bi 2008">Bi S, Earl LA, Jacobs L, Baum LG. Structural features of galectin-9 and galectin-1 that determine distinct T cell death pathways. J Biol Chem. 2008;283(18):12248-58</ref>.  There are has three well-characterized linker domains between the CRDs, generated by alternative splicing<ref name="Nishi 2006">Nishi N, Itoh A, Shoji H, Miyanaka H, Nakamura T. Galectin-8 and galectin-9 are novel substrates for thrombin. Glycobiology. 2006;16(11):15C-20C.</ref>, that may regulate cellular localization and function of the protein.  Truncation of linker domain between CRDs in recombinant forms of galectin-9 stabilize the protein to proteolysis<ref name="Nishi 2005">Nishi N, Itoh A, Fujiyama A, Yoshida N, Araya S, Hirashima M, Shoji H, Nakamura T. Development of highly stable galectins: truncation of the linker peptide confers protease-resistance on tandem-repeat type galectins. FEBS Lett. 2005;579(10):2058-64</ref>.

@@ Line 1: / Line 1: @@
-Galectin-9 is the best-studied of the tandem-repeat galectins and the crystal structure of the N-terminal carbohydrate recognition domain (CRD) is known. In addition, Galectin-9...
+Galectin-9 is one of the best-studied of the tandem-repeat galectins with glycan binding in both the N- and C-terminal domains <ref name="Wada 1997">Wada J, Kanwar YS. Identification and characterization of galectin-9, a novel beta-galactoside-binding mammalian lectin. J Biol Chem. 1997;272(9):6078-86</ref>.  The protein lacks a signal sequence, like most galectins, and is synthesized in the cytosol on free polyribosomes.  Galectin-9 is found outside of cells and may be exported by non-classical pathways.  Galectin-9 exhibits a variety of biological activities, the majority of which have focused on its immunomodulatory role toward lymphocytes, were it shows specific interactions with TIM-3, and can negatively regulate Th1 type immunity <ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref>.  Mammalian galectin-9 exhibits affinity toward select glycan ligands, including sulfated glycans, and blood group-related glycans, and also interacts with glycans containing poly-N-acetyllactosamine (LacNAc) repeats (-3Galβ1-4GlcNAcβ1-)n through recognition of internal LacNAc repeats <ref name="Nagae 2008">Nagae M, Nishi N, Nakamura-Tsuruta S, Hirabayashi J, Wakatsuki S, Kato R. Structural analysis of the human galectin-9 N-terminal carbohydrate recognition domain reveals unexpected properties that differ from the mouse orthologue. J Mol Biol. 2008;375(1):119-35</ref>).
-* uniquely binds poly-N-acetyllactosamine sequences by recognizing internal N-acetyllactosamine repeats<ref name="Nagae 2009">Nagae, M. et al. Structural analysis of the recognition mechanism of poly-N-acetyllactosamine by the human galectin-9 N-terminal carbohydrate recognition domain. Glycobiology 19, 112-117 (2009). </ref>
-* binds distinct ligands from [[Galectin-1]]<ref name="Bi 2008">Bi, S., Earl, L.A., Jacobs, L. & Baum, L.G. Structural features of galectin-9 and galectin-1 that determine distinct T cell death pathways. J Biol Chem 283, 12248-12258 (2008).</ref>
+The crystal structure of the N-terminal carbohydrate recognition domain (CRD) been defined
-* has three well-characterized linker domains between the CRDs, generated by alternative splicing, that regulate cellular localization and function of the protein
+<ref name="Nagae 2008"/><ref name="Yoshida 2010">Yoshida H, Teraoka M, Nishi N, Nakakita S, Nakamura T, Hirashima M, Kamitori S. X-ray structures of human galectin-9 C-terminal domain in complexes with a biantennary oligosaccharide and sialyllactose. J Biol Chem. 2010;285(47):36969-76. </ref>
-* is the only tandem-repeat galectin that has been administered in animal models of disease to assess therapeutic potential<ref name="Baba 2005">Baba, M. et al. Galectin-9 inhibits glomerular hypertrophy in db/db diabetic mice via cell-cycle-dependent mechanisms. J Am Soc Nephrol 16, 3222-3234 (2005). </ref><ref name="Seki 2008">Seki, M. et al. Galectin-9 suppresses the generation of Th17, promotes the induction of regulatory T cells, and regulates experimental autoimmune arthritis. Clin Immunol 127, 78-88 (2008).</ref><ref name="Tsuchiyama 2000">Tsuchiyama, Y. et al. Efficacy of galectins in the amelioration of nephrotoxic serum nephritis in Wistar Kyoto rats. Kidney Int 58, 1941-1952 (2000). </ref>
+<ref name="Nagae 2006">Nagae M, Nishi N, Murata T, Usui T, Nakamura T, Wakatsuki S, Kato R. Crystal structure of the galectin-9 N-terminal carbohydrate recognition domain from Mus musculus reveals the basic mechanism of carbohydrate recognition. J Biol Chem. 2006;281(47):35884-93.</ref>.  The GBP shows strong interactions in a metal-free manner with poly-N-acetyllactosamine sequences comprised of repeating (-3Galβ1-4GlcNAcβ1-)n by recognizing internal N-acetyllactosamine repeats<ref name="Nagae 2008"/>.  Generally, it binds distinct glycan ligands from [[Galectin-1]] <ref name="Bi 2008">Bi S, Earl LA, Jacobs L, Baum LG. Structural features of galectin-9 and galectin-1 that determine distinct T cell death pathways. J Biol Chem. 2008;283(18):12248-58</ref>.  There are has three well-characterized linker domains between the CRDs, generated by alternative splicing<ref name="Nishi 2006">Nishi N, Itoh A, Shoji H, Miyanaka H, Nakamura T. Galectin-8 and galectin-9 are novel substrates for thrombin. Glycobiology. 2006;16(11):15C-20C.</ref>, that may regulate cellular localization and function of the protein.  Truncation of linker domain between CRDs in recombinant forms of galectin-9 stabilize the protein to proteolysis<ref name="Nishi 2005">Nishi N, Itoh A, Fujiyama A, Yoshida N, Araya S, Hirashima M, Shoji H, Nakamura T. Development of highly stable galectins: truncation of the linker peptide confers protease-resistance on tandem-repeat type galectins. FEBS Lett. 2005;579(10):2058-64</ref>.
-* null mice have increased susceptibility to autoimmune disease
 == CFG Participating Investigators contributing to the understanding of this paradigm ==

@@ Line 35: / Line 35: @@
 === Biological roles of GBP-ligand interaction ===
+It has been shown that galectin-9 binds to a unique glycoprotein ligand Tim-3 expressed in Th1 and Th17 cells<ref name="Seki 2008">Seki M, Oomizu S, Sakata KM, Sakata A, Arikawa T, Watanabe K, Ito K, Takeshita K, Niki T, Saita N, Nishi N, Yamauchi A, Katoh S, Matsukawa A, Kuchroo V, Hirashima M. Galectin-9 suppresses the generation of Th17, promotes the induction of regulatory T cells, and regulates experimental autoimmune arthritis. Clin Immunol. 2008;127(1):78-88.</ref><ref name="Niwa 2009">Niwa H, Satoh T, Matsushima Y, Hosoya K, Saeki K, Niki T, Hirashima M, Yokozeki H. Stable form of galectin-9, a Tim-3 ligand, inhibits contact hypersensitivity and psoriatic reactions: a potent therapeutic tool for Th1- and/or Th17-mediated skin inflammation. Clin Immunol. 2009;132(2):184-94.</ref><ref name="Naka 2009">Naka EL, Ponciano VC, Cenedeze MA, Pacheco-Silva A, Camara NO. Detection of the Tim-3 ligand, galectin-9, inside the allograft during a rejection episode. Int Immunopharmacol. 2009;9(6):658-62.</ref><ref name="Anderson 2007">Anderson DE. TIM-3 as a therapeutic target in human inflammatory diseases. Expert Opin Ther Targets. 2007;11(8):1005-9.</ref>.  In addition, galectin-9 can interact with protein disulfide isomerase (PDI) at the cell surface, increasing retention of PDI on the surface and altering surface redox potential<ref name="Bi 2011">Bi S, Hong PW, Lee B, Baum LG. Galectin-9 binding to cell surface protein disulfide isomerase regulates the redox environment to enhance T-cell migration and HIV entry. Proc Natl Acad Sci U S A. 2011;108(26):10650-5</ref>.  Galectin-9 null-mice have interesting phenotypes related to immune regulation.   Galectin-9 null-mice develop acute and memory responses to Herpes Simplex Virus (HSV) that are of greater magnitude and better quality than those that occur in wild-type infected animals<ref name="Sehrawat 2010">Sehrawat S, Reddy PB, Rajasagi N, Suryawanshi A, Hirashima M, Rouse BT. Galectin-9/TIM-3 interaction regulates virus-specific primary and memory CD8 T cell response. PLoS Pathog. 2010;6(5):e1000882.</ref>; they exhibit increased resistance to influenza A virus compared to wild-type mice <ref name="Sharma 2011">Sharma S, Sundararajan A, Suryawanshi A, Kumar N, Veiga-Parga T, Kuchroo VK, Thomas PG, Sangster MY, Rouse BT. T cell immunoglobulin and mucin protein-3 (Tim-3)/Galectin-9 interaction regulates influenza A virus-specific humoral and CD8 T-cell responses. Proc Natl Acad Sci U S A. 2011;108(47):19001-6</ref>; and they exhibit susceptibility to experimentally-induced autoimmune disease <ref name="Seki 2008"/>.  Galectin-9 expression is elevated in peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus<ref name="Wang 2008">Wang Y, Meng J, Wang X, Liu S, Shu Q, Gao L, Ju Y, Zhang L, Sun W, Ma C. Expression of human TIM-1 and TIM-3 on lymphocytes from systemic lupus erythematosus patients. Scand J Immunol. 2008;67(1):63-70</ref>. Galectin-9 is the only tandem-repeat galectin that has been administered in animal models of disease to assess therapeutic potential <ref name="Seki 2008"/><ref name="Tsuchiyama 2000">Tsuchiyama Y, Wada J, Zhang H, Morita Y, Hiragushi K, Hida K, Shikata K, Yamamura M, Kanwar YS, Makino H. Efficacy of galectins in the amelioration of nephrotoxic serum nephritis in Wistar Kyoto rats. Kidney Int. 2000;58(5):1941-52.</ref><ref name="Baba 2005">Baba M, Wada J, Eguchi J, Hashimoto I, Okada T, Yasuhara A, Shikata K, Kanwar YS, Makino H. Galectin-9 inhibits glomerular hypertrophy in db/db diabetic mice via cell-cycle-dependent mechanisms. J Am Soc Nephrol. 2005;16(11):3222-34.</ref>. Galectin-9 exhibits the ability induce apoptosis in some lymphocytes <ref name="Zhu 2005">Zhu C, Anderson AC, Schubart A, Xiong H, Imitola J, Khoury SJ, Zheng XX, Strom TB, Kuchroo VK. The Tim-3 ligand galectin-9 negatively regulates T helper type 1 immunity. Nat Immunol. 2005;6(12):1245-52.</ref><ref name="Bi 2011">Bi S, Hong PW, Lee B, Baum LG. Galectin-9 binding to cell surface protein disulfide isomerase regulates the redox environment to enhance T-cell migration and HIV entry. Proc Natl Acad Sci U S A. 2011;108(26):10650-5.</ref> and this can be inhibited by inclusion of lactose or inhibitors.   Galectin-9 has eosinophil chemoattractant activity (26), and the term Ecalectin was given to a variant of T lymphocyte-derived galectin-9 that was found to be an eosinophil chemoattractant <ref name="Matsumoto 1998">Matsumoto R, Matsumoto H, Seki M, Hata M, Asano Y, Kanegasaki S, Stevens RL, Hirashima M. Human ecalectin, a variant of human galectin-9, is a novel eosinophil chemoattractant produced by T lymphocytes. J Biol Chem. 1998;273(27):16976-84</ref>.
 == CFG resources used in investigations ==

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 <br>
 === Structure ===
 === Biological roles of GBP-ligand interaction ===

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 === Cellular expression of GBP and ligands ===
-Galectin-9 is widely expressed in various tissues (heart, lung, liver, kidney, spleen, muscle, intestine, and thymus), but weakly expressed in brain<ref>Wada J, Ota K, Kumar A, Wallner EI, Kanwar YS. Developmental regulation, expression, and apoptotic potential of galectin-9, a beta-galactoside binding lectin. J Clin Invest. 1997;99(10):2452-61</ref>. Interestingly, the rat urate transporter was reported to be 99% identical to the sequence reported for rat galectin-9 <ref>Leal-Pinto E, Tao W, Rappaport J, Richardson M, Knorr BA, Abramson RG. Molecular cloning and functional reconstitution of a urate transporter/channel. J Biol Chem. 1997;272(1):617-25</ref>, suggesting that these two proteins are the same<ref>Lipkowitz MS, Leal-Pinto E, Rappoport JZ, Najfeld V, Abramson RG. Functional reconstitution, membrane targeting, genomic structure, and chromosomal localization of a human urate transporter. J Clin Invest. 2001;107(9):1103-15.</ref><ref>Lipkowitz MS, Leal-Pinto E, Cohen BE, Abramson RG. Galectin 9 is the sugar-regulated urate transporter/channel UAT. Glycoconj J. 2004;19(7-9):491-8</ref>, and suggest that galectin-9 may have multiple functions, occurring as a polytopic transmembrane protein to function as the urate transporter, and as a soluble protein in its signaling and cell-binding forms.
+Galectin-9 is widely expressed in various tissues (heart, lung, liver, kidney, spleen, muscle, intestine, and thymus), but weakly expressed in brain<ref name="Wada 1997">Wada J, Ota K, Kumar A, Wallner EI, Kanwar YS. Developmental regulation, expression, and apoptotic potential of galectin-9, a beta-galactoside binding lectin. J Clin Invest. 1997;99(10):2452-61</ref>. Interestingly, the rat urate transporter was reported to be 99% identical to the sequence reported for rat galectin-9 <ref name="Leal-Pinto 1997">Leal-Pinto E, Tao W, Rappaport J, Richardson M, Knorr BA, Abramson RG. Molecular cloning and functional reconstitution of a urate transporter/channel. J Biol Chem. 1997;272(1):617-25</ref>, suggesting that these two proteins are the same<ref name="Lipkowitz 2001">Lipkowitz MS, Leal-Pinto E, Rappoport JZ, Najfeld V, Abramson RG. Functional reconstitution, membrane targeting, genomic structure, and chromosomal localization of a human urate transporter. J Clin Invest. 2001;107(9):1103-15.</ref><ref name="Lipkowitz 2004">Lipkowitz MS, Leal-Pinto E, Cohen BE, Abramson RG. Galectin 9 is the sugar-regulated urate transporter/channel UAT. Glycoconj J. 2004;19(7-9):491-8</ref>, and suggest that galectin-9 may have multiple functions, occurring as a polytopic transmembrane protein to function as the urate transporter, and as a soluble protein in its signaling and cell-binding forms.
 === Biosynthesis of ligands ===

@@ Line 16: / Line 16: @@
 Human galectin-9 binding to glycans has been studied by a variety of techniques including glycan microarray analysis and frontal affinity chromatography.
-On the CFG glycan microarray, the individual N- and C-terminal domains of recombinant dog (Canis lupus) galectin-9, generated as GST (glutathione-S-transferase) chimeras, showed similarities in glycan recognition, but also distinct differences<ref>Poland PA, Rondanino C, Kinlough CL, Heimburg-Molinaro J, Arthur CM, Stowell SR, Smith DF, Hughey RP. Identification and characterization of endogenous galectins expressed in Madin Darby canine kidney cells. J Biol Chem. 2011;286(8):6780-90</ref>.  While both domains bound well to short sulfated glycans, such as 3-O-sulfated galactose in short LacNAc structures, only the N-terminal domain bound well to many glycans expressing blood group A-related sequences and to the Forssman glycolipid-like glycans, whereas the C-terminal domain bound less well to the blood group related structures, but showed binding to a linear sialylated poly-N-acetyllactosamine pentasaccharide.
+On the CFG glycan microarray, the individual N- and C-terminal domains of recombinant dog (Canis lupus) galectin-9, generated as GST (glutathione-S-transferase) chimeras, showed similarities in glycan recognition, but also distinct differences<ref name="Poland 2011">Poland PA, Rondanino C, Kinlough CL, Heimburg-Molinaro J, Arthur CM, Stowell SR, Smith DF, Hughey RP. Identification and characterization of endogenous galectins expressed in Madin Darby canine kidney cells. J Biol Chem. 2011;286(8):6780-90</ref>.  While both domains bound well to short sulfated glycans, such as 3-O-sulfated galactose in short LacNAc structures, only the N-terminal domain bound well to many glycans expressing blood group A-related sequences and to the Forssman glycolipid-like glycans, whereas the C-terminal domain bound less well to the blood group related structures, but showed binding to a linear sialylated poly-N-acetyllactosamine pentasaccharide.
-In frontal affinity chromatography, recombinant human galectin-9 was found to preferentially bind to both branched N-glycans (Kd = 0.16 μM toward tetraantennary N-glycans terminating in galactose) and glycans with poly-N-acetyllactosamine sequences (Kd = 0.09 μM toward octasaccharides with 4 repeating LacNAc groups, and this was found for both the N- and C-terminal domains.  By contrast, the N-terminal, but not the C-terminal domain, showed significant binding in the low μM range to Forssman glycolipid-derived pentasaccharides and to blood group A hexasaccharide<ref>Hirabayashi J, Hashidate T, Arata Y, Nishi N, Nakamura T, Hirashima M, Urashima T, Oka T, Futai M, Muller WE, Yagi F, Kasai K. Oligosaccharide specificity of galectins: a search by frontal affinity chromatography. Biochim Biophys Acta. 2002;1572(2-3):232-54</ref>.
+In frontal affinity chromatography, recombinant human galectin-9 was found to preferentially bind to both branched N-glycans (Kd = 0.16 μM toward tetraantennary N-glycans terminating in galactose) and glycans with poly-N-acetyllactosamine sequences (Kd = 0.09 μM toward octasaccharides with 4 repeating LacNAc groups, and this was found for both the N- and C-terminal domains.  By contrast, the N-terminal, but not the C-terminal domain, showed significant binding in the low μM range to Forssman glycolipid-derived pentasaccharides and to blood group A hexasaccharide<ref name="Hirabayashi 2012">Hirabayashi J, Hashidate T, Arata Y, Nishi N, Nakamura T, Hirashima M, Urashima T, Oka T, Futai M, Muller WE, Yagi F, Kasai K. Oligosaccharide specificity of galectins: a search by frontal affinity chromatography. Biochim Biophys Acta. 2002;1572(2-3):232-54</ref>.
-Glycan microarray analyses in microarrays with relatively short glycan species<ref>Horlacher T, Oberli MA, Werz DB, Krock L, Bufali S, Mishra R, Sobek J, Simons K, Hirashima M, Niki T, Seeberger PH. Determination of carbohydrate-binding preferences of human galectins with carbohydrate microarrays. Chembiochem. 2010;11(11):1563-73</ref>, showed that both the recombinant full-length human galectin-9 and the N-terminal domain displayed very similar binding patterns, and both bound to LacNAc sequences and even better to short fucosylated glycans with terminal blood group A and B trisaccharide sequences.
+Glycan microarray analyses in microarrays with relatively short glycan species<ref name="Horlacher 2010">Horlacher T, Oberli MA, Werz DB, Krock L, Bufali S, Mishra R, Sobek J, Simons K, Hirashima M, Niki T, Seeberger PH. Determination of carbohydrate-binding preferences of human galectins with carbohydrate microarrays. Chembiochem. 2010;11(11):1563-73</ref>, showed that both the recombinant full-length human galectin-9 and the N-terminal domain displayed very similar binding patterns, and both bound to LacNAc sequences and even better to short fucosylated glycans with terminal blood group A and B trisaccharide sequences.
 === Cellular expression of GBP and ligands ===