label: glucuronyl-galactosyl-proteoglycan 4-alpha-N-acetylglucosaminyltransferase activity
label_lc: glucuronyl-galactosyl-proteoglycan 4-alpha-n-acetylglucosaminyltransferase activity
description: "Catalysis of the reaction: 3-O-(beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + UDP-N-acetyl-alpha-D-glucosamine = 3-O-(alpha-D-GlcNAc-(1->4)-beta-D-GlcA-(1->3)-beta-D-Gal-(1->3)-beta-D-Gal-(1->4)-beta-D-Xyl)-L-seryl-[protein] + H+ + UDP."