Glucosaminyl-N-Acetyl Transferase 3 (GCNT3)

Mucin-type glycoproteins are unique in that they have clusters of O-glycans containing N-acetylgalactosamine residues at reducing ends, which are linked to serine or threonine. O-glycans are classified according to the core structures, which can be converted in the presence of an N-acetylglucosaminyltransferase, such as GCNT3.The deduced 438-amino acid type II transmembrane protein is 48% and 34% identical to GCNT1 and GCNT2, respectively, and contains A, B, and C regions in its catalytic domain that are homologous to regions in GCNT1 and GCNT2. GCNT3 also has 2 potential N-glycosylation sites. Northern blot analysis revealed predominant expression of multiple transcripts in colon, small intestine, trachea, stomach, and thyroid, with weak expression in testis, prostate, kidney, and pancreas.