Known as: UDP-N-acetyl-D-glucosamine:beta-D-glucuronosyl-(1,3)-beta-D-galactosyl-(1,3)-beta-D-galactosyl-(1,4)-beta-D-xylosyl-proteoglycan 4IV-alpha-N-acetyl-D-glucosaminyltransferase activity, alpha1,4-N-acetylglucosaminyltransferase activity, alpha-N-acetylglucosaminyltransferase I activity
Catalysis of the reaction: UDP-N-acetyl-D-glucosamine + beta-D-glucuronosyl-(1->3)-beta-D-galactosyl-(1->3)-beta-D-galactosyl-(1->4)-beta-D…