Molecular cloning and expression of mouse ceramide glucosyltransferase.

Ceramide glucosyltransferase (EC 2.4.1.80) catalyzes the first glycosylation step of glycosphingolipid (GSL) synthesis, the transfer of glucose from UDP-Glucose to hydrophobic ceramide and generate glucosylceramide (GlcCer). We have cloned mouse ceramide glucosyltransferase cDNA from a brain cDNA library by PCR based homology cloning. The nucleotide sequence determination revealed that mouse ceramide glucosyltransferase cDNA encodes 394 amino acids with a calculated molecular mass of 45 kDa. The amino acid sequence of mouse ceramide glucosyltransferase showed 98% identity with the human sequence. Homology searches against currently available databases identified three homologous proteins in Caenorhabditis elegans and one homologous protein in Cyanobacteria. Highly conserved sequences of ceramide glucosyltransferases and the homologs among a wide variety of organisms suggest biological significance of the lipid glucosylation system.