High impact information on B3gat1

• Regions that expressed GlcAT-D and/or GlcAT-P were always HNK-1-positive, indicating that both GlcATs are involved in the synthesis of the HNK-1 epitope in vivo [1].
• GlcAT-P was able to transfer glucuronic acid to oligosaccharide chains on asialoorosomucoid [2].
• The acceptor specificity and tissue distribution suggest that a novel glucuronyltransferase, GlcAT-P, is involved in the biosynthesis of the sulfoglucuronylgalactose structure in the HNK-1 carbohydrate epitope that is expressed on glycoproteins [2].
• The enzyme recovered predominantly in the effluent fraction (GlcAT-L) catalyzed the transfer of glucuronic acid to glycolipid acceptors but not to glycoprotein acceptors, whereas the enzyme recovered in the eluate fraction (GlcAT-P) transferred glucuronic acid most predominantly to glycoprotein acceptors and very little to glycolipid acceptors [2].
• The amino acid sequence revealed 49% homology to rat GlcAT-P, a glucuronyltransferase involved in the biosynthesis of the HNK-1 carbohydrate epitope of glycoproteins, [Terayama et al. (1997) Proc. Natl. Acad. Sci. USA 94, 6093-6098] and the highest sequence homology was found in the catalytic region [3].

Biological context of B3gat1

• The amino acid sequence of GlcAT-D displayed 50.0% identity to rat GlcAT-P, which is involved in the biosynthesis of the HNK-1 epitope on glycoproteins [1].

Anatomical context of B3gat1

• GlcAT-P gene was expressed in the non-migrating longitudinal fibers, whereas GlcAT-D gene was expressed in the migrating myoblasts in the limb bud [4].
• The GlcAT-P gene, encoding an enzyme for the synthesis of the HNK-1 epitope, was also expressed ectopically in the frontonasal epithelium of the mutant [5].
• Interestingly, the NCCs in the cranial ganglia expressed the GlcAT-D gene, whereas the migrating trunk NCCs expressed the GlcAT-P gene [6].

Associations of B3gat1 with chemical compounds

• The GlcAT-P transferred glucuronic acid to the galactose residues in the N-acetyllactosamine branches of bi-, tri-, and tetra-antennary oligosaccharide chains, with different efficiencies and most preferentially to those in the Galbeta1-4GlcNAcbeta1-4Manalpha1-3 branch [7].

Analytical, diagnostic and therapeutic context of B3gat1

• In situ hybridization analysis revealed that the expression pattern of GlcAT-D transcript in embryo is similar to that of GlcAT-P, but distinct expression of GlcAT-D was observed in the embryonic pallidum and retina [1].

References