Enzymes belonging to glycosyltransferase family 18 (alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase) contribute to the creation of branches in complex-type N-glycans. This domain is responsible for the catalytic activity of the enzyme [1].

1: The Caenorhabditis elegans gene, gly-2, can rescue the N-acetylglucosaminyltransferase V mutation of Lec4 cells. Warren CE, Krizus A, Roy PJ, Culotti JG, Dennis JW; J Biol Chem. 2002;277:22829-22838. PMID:11937505