May be involved in protein N-glycosylation, second step of the dolichol-linked oligosaccharide pathway. N-acetyl-alpha-D-glucosaminyl-diphosphodolichol + UDP-N-acetyl-alpha-D-glucosamine = H(+) + N,N'-diacetylchitobiosyl diphosphodolichol + UDP May interact with ALG14. Could be recruited to the cytosolic face of the endoplasmic reticulum membrane through its interaction with ALG14. Belongs to the glycosyltransferase 28 family.