Protein O-Fucosyltransferase 2 (POFUT2)

POFUT2 is an enzyme responsible for adding fucose sugars in O linkage to serine or threonine residues in Thrombospondin repeats. The protein is an inverting glycosyltransferase, which means that the enzyme uses GDP-β-L-fucose as a donor substrate and transfers the fucose in O linkage to the protein producing fucose-α-O-serine/threonine.

Almost all glycosyltransferases reside in the Golgi apparatus. However, POFUT2 as well as the related enzyme POFUT1 have recently been shown to reside in the endoplasmic reticulum.The deduced protein contains 428 amino acids. RT-PCR ELISA detected moderate expression in all adult and fetal tissues and specific brain regions examined. Crystal structures of POFUT2 reveal a variation of the classical GT-B fold and identify sugar donor and TSR acceptor binding sites.