B4GALT2, Beta-1,4-galactosyltransferase 2, UDP-Gal:beta-GlcNAc beta-1,4-galactosyltransferase 2, UDP-galactose:beta-N-acetylglucosamine beta-1,4-galactosyltransferase 2, Lactose synthase A protein, N-acetyllactosamine synthase, Nal synthase, Beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase, Beta-N-acetylglucosaminyl-glycolipid beta-1,4-galactosyltransferase

B4GALT2 is one of type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose; all transfer galactose in a beta1,4 linkage to similar acceptor sugars: GlcNAc, Glc, and Xyl. Each beta4GalT has a distinct function in the biosynthesis of different glycoconjugates and saccharide structures. As type II membrane proteins, they have an N-terminal hydrophobic signal sequence that directs the protein to the Golgi apparatus and which then remains uncleaved to function as a transmembrane anchor. By sequence similarity, the beta4GalTs form four groups: beta4GalT1 and beta4GalT2, beta4GalT3 and beta4GalT4, beta4GalT5 and beta4GalT6, and beta4GalT7. The enzyme synthesizes N-acetyllactosamine in glycolipids and glycoproteins. Its substrate specificity is affected by alpha-lactalbumin but it is not expressed in lactating mammary tissue.