Glucosylceramide synthase catalyzes the first glycosylation step of glycosphingolipid synthesis.
UDP-glucose:N-acylsphingosine D-glucosyltransferase (glucosylceramide synthase or ceramide glucosyltransferase) catalyzes the first glycosylation step of glycosphingolipid synthesis. Its product, glucosylceramide, serves as the core of more than 300 glycosphingolipids (GSL). GSLs are a group of membrane components that have the lipid portion embedded in the outer plasma membrane leaflet and the sugar chains extended to the outer environment. Several lines of evidence suggest the importance of GSLs in various cellular processes such as differentiation, adhesion, proliferation, and cell-cell recognition. In pathogenic fungus Cryptococcus neoformans, glucosylceramide serves as an antigen that elicits an antibody response in patients and it is essential for fungal growth in host extracellular environment.