Beta-1,4-glucuronyltransferase 1 (B4GAT1)

Beta-1,4-glucuronyltransferase involved in O- mannosylation of alpha-dystroglycan (DAG1). Transfers a glucuronic acid (GlcA) residue on a xylose (Xyl) acceptor to produce the glucuronyl-beta-1,4-xylose-beta disaccharide primer, which can be further elongated by LARGE1, during synthesis of phosphorylated O- mannosyl glycan (PubMed:25279699, PubMed:25279697).

Phosphorylated O-mannosyl glycan is a carbohydrate is a carbohydrate structure present in alpha-dystroglycan (DAG1), which is required for binding laminin G-like domain-containing extracellular proteins with high affinity (PubMed:25279699, PubMed:25279697). Required for axon guidance; through its role in O-mannosylation of alpha- dystroglycan (DAG1) (By similarity).