Term Name:	acetylgalactosaminyl-O-glycosyl-glycoprotein beta-1,3-N-acetylglucosaminyltransferase activity
Synonyms:	core 3-beta-GlcNAc-transferase activity, core 3beta-GlcNAc-transferase activity, mucin core 3 beta3-GlcNAc-transferase activity, O-glycosyl-oligosaccharide-glycoprotein N-acetylglucosaminyltransferase III activity, UDP-N-acetyl-D-glucosamine:O-glycosyl-glycoprotein (N-acetyl-D-glucosamine to N-acetyl-D-galactosaminyl-R) beta-1,3-N-acetyl-D-glucosaminyltransferase activity, uridine diphosphoacetylglucosamine-mucin beta(1->3)-acetylglucosaminyltransferase activity
Definition:	Catalysis of the reaction: 3-O-N-acetyl-D-galactosalaminyl-[protein] + UDP-N-acetyl-D-glucosamine = 3-O-N-acetyl-beta-D-glucosaminyl-1,3-N-acetyl-D-galactosaminyl-[protein] + UDP. Linkage of the glycan to the protein occurs via the oxygen atom in the side chain of an L-serine or L-threonine residue.
Ontology:	GO: Molecular Function [GO:0047224]    QuickGO    AmiGO