B4GALT1

Beta-1,4-galactosyltransferase 1 is an enzyme that in humans is encoded by the B4GALT1 gene.[5][6]

B4GALT1
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 2AE7, 2AEC, 2AES, 2AGD, 2AH9, 2FY7, 2FYA, 2FYB, 3EE5, 4EE3, 4EE4, 4EE5, 4EEA, 4EEG, 4EEM, 4EEO, 4L41
Identifiers
Aliases	B4GALT1, B4GAL-T1, CDG2D, GGTB2, GT1, GTB, beta4Gal-T1, beta-1,4-galactosyltransferase 1
External IDs	OMIM: 137060 MGI: 95705 HomoloGene: 20378 GeneCards: B4GALT1
Gene location (Human) Chr. Chromosome 9 (human)[1] Band 9p21.1 Start 33,104,082 bp[1] End 33,167,356 bp[1]
Gene location (Mouse) Chr. Chromosome 4 (mouse)[2] Band 4 A5|4 20.46 cM Start 40,804,602 bp[2] End 40,854,005 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in stromal cell of endometrium left uterine tube minor salivary gland gallbladder smooth muscle tissue left lobe of thyroid gland right lobe of thyroid gland right lobe of liver upper lobe of left lung right lung Top expressed in lacrimal gland pyloric antrum mucous cell of stomach cumulus cell crypt of lieberkuhn of small intestine submandibular gland intestinal villus molar conjunctival fornix placenta More reference expression data BioGPS More reference expression data
Gene ontology Molecular function protein homodimerization activity cytoskeletal protein binding alpha-tubulin binding glycosyltransferase activity lactose synthase activity transferase activity beta-tubulin binding UDP-galactosyltransferase activity metal ion binding manganese ion binding N-acetyllactosamine synthase activity galactosyltransferase activity beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase activity Cellular component Golgi cisterna membrane Golgi membrane desmosome extracellular region filopodium brush border membrane Golgi trans cisterna integral component of membrane cell projection cell surface external side of plasma membrane extracellular exosome basolateral plasma membrane plasma membrane Golgi apparatus membrane extracellular space secretory granule membrane azurophil granule membrane Biological process regulation of acrosome reaction glycoprotein biosynthetic process epithelial cell development penetration of zona pellucida cell adhesion lactose biosynthetic process extracellular matrix organization positive regulation of apoptotic process involved in mammary gland involution positive regulation of epithelial cell proliferation involved in wound healing angiogenesis involved in wound healing leukocyte migration wound healing binding of sperm to zona pellucida protein glycosylation acute inflammatory response branching morphogenesis of an epithelial tube negative regulation of cell population proliferation galactose metabolic process development of secondary sexual characteristics keratan sulfate biosynthetic process mammary gland development regulation of cell population proliferation positive regulation of apoptotic process protein N-linked glycosylation oligosaccharide biosynthetic process neutrophil degranulation protein homooligomerization carbohydrate metabolic process Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 2683 14595 Ensembl ENSG00000086062 ENSMUSG00000028413 UniProt P15291 Q86XA6 P15535 RefSeq (mRNA) NM_001497 NM_022305 NM_001378519 RefSeq (protein) NP_001488 NP_001365424 NP_001365425 NP_001365426 NP_071641 NP_001365448 Location (UCSC) Chr 9: 33.1 – 33.17 Mb Chr 4: 40.8 – 40.85 Mb PubMed search [3] [4]
Wikidata
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This gene is one of seven beta-1,4-galactosyltransferase (beta4GalT) genes. They encode 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. This gene is unique among the beta4GalT genes because it encodes an enzyme that participates both in glycoconjugate and lactose biosynthesis. For the first activity, the enzyme adds galactose to N-acetylglucosamine residues that are either monosaccharides or the nonreducing ends of glycoprotein carbohydrate chains. The second activity is restricted to lactating mammary tissues where the enzyme forms a heterodimer with alpha-lactalbumin to catalyze UDP-galactose + D-glucose <=> UDP + lactose. The two enzymatic forms result from alternate transcription initiation sites and post-translational processing. Two transcripts, which differ only at the 5' end, with approximate lengths of 4.1 kb and 3.9 kb encode the same protein. The longer transcript encodes the type II membrane-bound, trans-Golgi resident protein involved in glycoconjugate biosynthesis. The shorter transcript encodes a protein which is cleaved to form the soluble lactose synthase.[6]