Histo-blood group ABO system transferase
Domain
The conserved DXD motif is involved in cofactor binding. The manganese ion interacts with the beta-phosphate group of UDP and may also have a role in catalysis.
Function
This protein is the basis of the ABO blood group system. The histo-blood group ABO involves three carbohydrate antigens: A, B, and H. A, B, and AB individuals express a glycosyltransferase activity that converts the H antigen to the A antigen (by addition of UDP-GalNAc) or to the B antigen (by addition of UDP-Gal), whereas O individuals lack such activity.
Glycosyltransferase that catalyzes the transfer of carbohydrates to H antigen, forming the antigenic structures of the ABO blood group.
Pathway
Protein modification; protein glycosylation.
Post-translational modifications
The soluble form derives from the membrane form by proteolytic processing.
Sequence Similarities
Belongs to the glycosyltransferase 6 family.
Tissue Specificity
Expressed at high levels in testis. Also expressed in pancreas, uterus and lung and salivary gland.
Cellular localization
- Golgi apparatus
- Golgi stack membrane
- Single-pass type II membrane protein
- Secreted
- Membrane-bound form in trans cisternae of Golgi. Secreted into the body fluid.
Alternative names
Histo-blood group ABO system transferase, Fucosylglycoprotein 3-alpha-galactosyltransferase, Fucosylglycoprotein alpha-N-acetylgalactosaminyltransferase, Glycoprotein-fucosylgalactoside alpha-N-acetylgalactosaminyltransferase, Glycoprotein-fucosylgalactoside alpha-galactosyltransferase, Histo-blood group A transferase, Histo-blood group B transferase, NAGAT, A transferase, B transferase, ABO