MOLECULAR-CLONING AND EXPRESSION OF MOUSE CERAMIDE GLUCOSYLTRANSFERASE

Ceramide glucosyltransferase (EC 2.4.1.80) catalyzes the first glycosy lation step of glycosphingolipid (GSL) synthesis, the transfer of gluc ose from UDP-Glucose to hydrophobic ceramide and generate glucosylcera mide (GlcCer). We have cloned mouse ceramide glucosyltransferase cDNA from a brain cDNA library by PCR based homology cloning. The nucleotid e sequence determination revealed that mouse ceramide glucosyltransfer ase cDNA encodes 394 amino acids with a calculated molecular mass of 4 5 kDa. The amino acid sequence of mouse ceramide glucosyltransferase s howed 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. Hi ghly conserved sequences of ceramide glucosyltransferases and the homo logs among a wide variety of, organisms suggest biological significanc e of the lipid glucosylation system.