@article{ebfa58c0849c11dd81b0000ea68e967b,
title = "The Drosophila gene brainiac encodes a glycosyltransferase putatively involved in glycosphingolipid synthesis.",
abstract = "The Drosophila genes fringe and brainiac exhibit sequence similarities to glycosyltransferases. Drosophila and mammalian fringe homologs encode UDP-N-acetylglucosamine:fucose-O-Ser beta1,3-N-acetylglucosaminyltransferases that modulate the function of Notch family receptors. The biological function of brainiac is less well understood. brainiac is a member of a large homologous mammalian beta3-glycosyltransferase family with diverse functions. Eleven distinct mammalian homologs have been demonstrated to encode functional enzymes forming beta1-3 glycosidic linkages with different UDP donor sugars and acceptor sugars. The putative mammalian homologs with highest sequence similarity to brainiac encode UDP-N-acetylglucosamine:beta1,3-N-acetylglucosaminyltransferases (beta3GlcNAc-transferases), and in the present study we show that brainiac also encodes a beta3GlcNAc-transferase that uses beta-linked mannose as well as beta-linked galactose as acceptor sugars. The inner disaccharide core structures of glycosphingolipids in mammals (Galbeta1-4Glcbeta1-Cer) and insects (Manbeta1-4Glcbeta1-Cer) are different. Both disaccharide glycolipids served as substrates for brainiac, but glycolipids of insect cells have so far only been found to be based on the GlcNAcbeta1-3Manbeta1-4Glcbeta1-Cer core structure. Infection of High Five(TM) cells with baculovirus containing full coding brainiac cDNA markedly increased the ratio of GlcNAcbeta1-3Manbeta1-4Glcbeta1-Cer glycolipids compared with Galbeta1-4Manbeta1-4Glcbeta1-Cer found in wild type cells. We suggest that brainiac exerts its biological functions by regulating biosynthesis of glycosphingolipids.",
author = "Tilo Schwientek and Birgit Keck and Levery, {Steven B} and Jensen, {Mads A} and Pedersen, {Johannes W} and Wandall, {Hans H} and Mark Stroud and Cohen, {Stephen M} and Margarida Amado and Henrik Clausen",
note = "Keywords: Animals; Baculoviridae; Cell Line; Chromatography, High Pressure Liquid; DNA, Complementary; Databases as Topic; Disaccharides; Dose-Response Relationship, Drug; Drosophila; Drosophila Proteins; Genes, Insect; Glycoside Hydrolases; Glycosphingolipids; Glycosyltransferases; Kinetics; Magnetic Resonance Spectroscopy; Membrane Proteins; Mutation; Phylogeny; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Substrate Specificity; Uridine Diphosphate",
year = "2002",
doi = "10.1074/jbc.M206213200",
language = "English",
volume = "277",
pages = "32421--9",
journal = "Journal of Biological Chemistry",
issn = "0021-9258",
publisher = "American Society for Biochemistry and Molecular Biology, Inc.",
number = "36",
}