B4GALT7 cDNA Clone – Xylosylprotein Beta 1,4-Galactosyltransferase, Polypeptide 7 (Galactosyltransferase I) (Human)

This gene is a member of the beta-1,4-galactosyltransferase (beta4GalT) family. Family members encode type II membrane-bound glycoproteins that appear to have exclusive specificity for the donor substrate UDP-galactose. Each beta4GalT member 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 which then remains uncleaved to function as a transmembrane anchor. The enzyme encoded by this gene attaches the first galactose in the common carbohydrate-protein linkage (GlcA-beta1,3-Gal-beta1,3-Gal-beta1,4-Xyl-beta1-O-Ser) found in proteoglycans. This enzyme differs from other beta4GalTs because it lacks the conserved Cys residues found in beta4GalT1-beta4GalT6 and it is located in cis-Golgi instead of trans-Golgi. Mutations in this gene have been associated with the progeroid form of Ehlers-Danlos syndrome. [provided by RefSeq, Oct 2009]

B4GALT7: Required for the biosynthesis of the tetrasaccharide linkage region of proteoglycans, especially for small proteoglycans in skin fibroblasts. Defects in B4GALT7 are the cause of Ehlers-Danlos syndrome progeroid type (EDSP). EDSP is a variant form of Ehlers-Danlos syndrome characterized by progeroid facies, mild mental retardation, short stature, skin hyperextensibility, moderate skin fragility, joint hypermobility principally in digits. Belongs to the glycosyltransferase 7 family.

Protein type: Transferase; EC 2.4.1.133; Glycan Metabolism - chondroitin sulfate biosynthesis; Glycan Metabolism - heparan sulfate biosynthesis; Membrane protein, integral

Chromosomal Location of Human Ortholog: 5q35.2-q35.3

Cellular Component: Golgi apparatus; Golgi membrane; integral to membrane

Molecular Function: beta-N-acetylglucosaminylglycopeptide beta-1,4-galactosyltransferase activity; galactosyltransferase activity; manganese ion binding; protein binding; xylosylprotein 4-beta-galactosyltransferase activity

Biological Process: fibril organization and biogenesis; glycosaminoglycan biosynthetic process; glycosaminoglycan metabolic process; negative regulation of fibroblast proliferation; protein amino acid N-linked glycosylation; protein modification process; proteoglycan metabolic process

Disease: Ehlers-danlos Syndrome, Progeroid Type, 1