Reaction catalyzed by alpha-1,3-mannosyl-glycoprotein 2-beta-N-acetylglucosaminyltransferase (2.4.1.101)

		+			=			+
	UDP-N-acetyl-D-glucosamine	+		alpha-D-mannosyl-1,3-beta-D-mannosyl-1,4-N-acetyl-D-glucosamine	=		UDP	+		N-acetyl-D-glucosaminyl-1,2-alpha-D-mannosyl-1,3-beta-D-mannosyl-1,4-N-acetyl-D-glucosamine