Ceramide glucosyltransferase (glucosylceramide synthase, GlcT-1, EC 2.4.1.80) catalyzes the first step in glycosphingolipid synthesis, the transfer of glucose from UDP-glucose to ceramide. The product, glucosylceramide, serves as a core structure for over 300 species of glycosphingolipids. The enzyme is a key regulatory factor controlling intracellular levels of ceramide and glycosphingolipids. We have cloned the gene for mouse ceramide glucosyltransferase, Ugcg. The gene spans approximately 32 kb and is composed of 9 exons and 8 introns. The promoter region was found to lack TATA and CAAT boxes but contains Spl binding sites, which are indicators of typical housekeeping genes. In addition to these general transcription factor binding sites, the motifs for AhR, NF-kappaB, AP-2 and GATA-1 binding sites were found.