Beta-1,4-galactosylation of N-glycans is a complex process.
Most beta-1,4-galactosyltransferase (beta-1,4-GalT)-knockout mice die after birth. Although several defects were found transiently in these animals, the primary cause of death is obscure. Not only beta-1,4-linked galactose residues on N-glycans, but also beta-1, 4-GalT activities were found in some of the tissues. Recently, five human genes which encode beta-1,4-GalTs have been cloned, and the possible presence of such novel beta-1,4-GalTs in mice is considered to bring about survival of the mutant animal beyond birth. In order to understand the semi-lethal nature of this animal, it is inevitable to clarify how individual novel beta-1,4-GalTs are involved in the biosynthesis of glycoconjugates based on their acceptor-substrate specificities.
Furukawa
K
K
Department of Biosignal Research, Tokyo Metropolitan Institute of Gerontology, Itabashi-ku, Tokyo, Japan. furukawa@tmig.or.jp
Sato
T
T
D000581:Amidohydrolases / Q000378:metabolism; D000595:Amino Acid Sequence; D000606:Amino Sugars / Q000096:biosynthesis; D000818:Animals; D001921:Brain / Q000378:metabolism; D002240:Carbohydrate Sequence; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism*; D006023:Glycoproteins / Q000096:biosynthesis; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D016415:Sequence Alignment; D012794:Sialic Acids / Q000378:metabolism; D013379:Substrate Specificity
D000606:Amino Sugars; D006023:Glycoproteins; D012794:Sialic Acids; C021319:polysialic acid; C000458:N-acetyllactosamine; D005700:Galactosyltransferases; C119701:beta-1,4-galactosyltransferase I; C111678:beta-1,4-galactosyltransferase IV; C023235:glucosylceramide beta-1-4-galactosyltransferase; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase