Biosynthetic Pathway of O-Mannosyl Glycan in Mammals

Glycosylation is the most frequent modification of proteins and is important for many ligand-receptor interactions. We have attempted to demonstrate the biosynthetic pathway and the function of O-mannosyl glycan since 1997 when the O-mannosyl glycan structure was identified. In this study, we have identified and characterized glycosyltransferases, POMT1, POMT2 and POMGnT1. Mutations in POMT1, POMT2 or POMGnT1 can lead to a congenital muscular dystrophy with abnormal neuronal migration. Our findings indicate that O-mannosyl glycan plays an important role in muscle and brain development. This review briefly outlines the biosynthetic mechanism of O-mannosyl glycan in mammals.