MOUSE LINES
Pomgnt1
Pomgnt1 (protein O-linked mannose b1,2 N-acetylglucosaminyltransferase 1) is required for the synthesis of the NeuAca2-3Galb1-4GlcNAcb1-2Mana1-O-Ser/Thr tetrasaccharide on a-dystroglycan. This tetrasaccharide is the major sialylated O-linked oligosaccharide involved in the binding of laminin to a-dystroglycan. Both a- and b-dystroglycans are components of the dystrophin-associated glycoprotein complex spanning the sarcolemma of skeletal muscle cells.
Several independent disease-causing mutations of the Pomgnt1 gene have been reported in patients with Muscle-Eye-Brain (MEB) disease (Yoshida A, et al. 2001, Michele D, et al. 2002). The abnormal glycan is believed to be responsible for disruption of ligand binding. MEB patients present with a wide spectrum of brain and eye malformation and suffer from various degrees of mental retardation.