A family of human beta3-galactosyltransferases. Characterization of four members of a UDP-galactose:beta-N-acetyl-glucosamine/beta-nacetyl-galactosamine beta-1,3-galactosyltransferase family.
BLAST analysis of expressed sequence tags (ESTs) using the coding sequence of a human UDP-galactose:beta-N-acetyl-glucosamine beta-1, 3-galactosyltransferase, designated beta3Gal-T1, revealed no ESTs with identical sequences but a large number with similarity. Three different sets of overlapping ESTs with sequence similarities to beta3Gal-T1 were compiled, and complete coding regions of these genes were obtained. Expression of two of these genes in the Baculo virus system showed that one represented a UDP-galactose:beta-N-acetyl-glucosamine beta-1, 3-galactosyltransferase (beta3Gal-T2) with similar kinetic properties as beta3Gal-T1. Another gene represented a UDP-galactose:beta-N-acetyl-galactosamine beta-1, 3-galactosyltransferase (beta3Gal-T4) involved in GM1/GD1 ganglioside synthesis, and this gene was highly similar to a recently reported rat GD1 synthase (Miyazaki, H., Fukumoto, S., Okada, M., Hasegawa, T., and Furukawa, K. (1997) J. Biol. Chem. 272, 24794-24799). Northern analysis of mRNA from human organs with the four homologous cDNA revealed different expression patterns. beta3Gal-T1 mRNA was expressed in brain, beta3Gal-T2 was expressed in brain and heart, and beta3Gal-T3 and -T4 were more widely expressed. The coding regions for each of the four genes were contained in single exons. beta3Gal-T2, -T3, and -T4 were localized to 1q31, 3q25, and 6p21.3, respectively, by EST mapping. The results demonstrate the existence of a family of homologous beta3-galactosyltransferase genes.
Amado
M
M
School of Dentistry, University of Copenhagen, Norre Allé 20, 2200 Copenhagen N, Denmark.
Almeida
R
R
Carneiro
F
F
Levery
S B
SB
Holmes
E H
EH
Nomoto
M
M
Hollingsworth
M A
MA
Hassan
H
H
Schwientek
T
T
Nielsen
P A
PA
Bennett
E P
EP
Clausen
H
H
D000595:Amino Acid Sequence; D000818:Animals; D002240:Carbohydrate Sequence; D002460:Cell Line; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D005700:Galactosyltransferases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D005810:Multigene Family; D051381:Rats; D017386:Sequence Homology, Amino Acid; D018411:Spodoptera
D005700:Galactosyltransferases