Glycosphingolipids (GSLs) are a group of membrane components that contain lipid and sugar moieties. They are present in essentially all animal cells and are believed to have important roles in various cellular processes. UDP-glucose ceramide glucosyltransferase (UGCG) catalyzes the first glycosylation step in GSL biosynthesis.
The product, glucosylceramide, is the core structure of more than 300 GSLs. Ichikawa et al. cloned a UGCG cDNA by expressing a human melanoma cell cDNA library in a UGCG-deficient cell line and screening for UGCG complementation. The predicted 394-amino acid UGCG protein has a potential signal-anchor sequence and a single transmembrane domain near the N terminus, and very hydrophobic regions close to the C terminus, which may interact with the membrane.