Reaction catalyzed by UDP-N-acetylglucosamine-lysosomal-enzyme N-acetylglucosaminephosphotransferase (2.7.8.17)

		+			=			+
	UDP-N-acetyl-D-glucosamine	+		lysosomal-enzyme D-mannose	=		UMP	+		lysosomal-enzyme N-acetyl-D-glucosaminyl-phospho-D-mannose