Accepted name: protein O-mannose β-1,4-N-acetylglucosaminyltransferase
Reaction: UDP-N-acetyl-α-D-glucosamine + 3-O-(α-D-mannosyl)-L-threonyl-[protein] = UDP + 3-O-[N-acetyl-β-D-glucosaminyl-(1→4)-α-D-mannosyl]-L-threonyl-[protein]
Other name(s): GTDC2 (gene name); POMGNT2
Systematic name: UDP-N-acetyl-α-D-glucosamine:α-D-mannosyl-threonyl-[protein] 4-β-N-acetyl-D-glucosaminyltransferase
Comments: The human protein is involved in the formation of a phosphorylated trisaccharide on a threonine residue of α-dystroglycan, an extracellular peripheral glycoprotein that acts as a receptor for extracellular matrix proteins containing laminin-G domains.
1.  Yoshida-Moriguchi, T., Willer, T., Anderson, M.E., Venzke, D., Whyte, T., Muntoni, F., Lee, H., Nelson, S.F., Yu, L. and Campbell, K.P. SGK196 is a glycosylation-specific O-mannose kinase required for dystroglycan function. Science 341 (2013) 896–899. [PMID: 23929950]
[EC created 2013]