MFNG is a 52-55kD member of the glucosyltransferase 31 family. It is a Golgi membrane protein that transfers N-acetylglucosamine to an O-linked fucose residue on Notch. Activity on Notch increases Delta-1 induced signaling while suppressing Jagged-1 signaling. MFNG is found in fetal pancreatic endocrine progenitor cells and immature ventricular zone neurons. Human MFNG is a 321aa type II transmembrane protein. It contains a short 7aa cytoplasmic region, plus a 294aa luminal domain (aa28-321). There are two potential splice variants, one that shows a 15aa substitution for aa104-321, and another that contains a three aa substitution for aa86-102. Over aa37-321, human MFNG shares 85% aa identity with mouse MFNG.