Sialyltransferase 6 (SIAT6)

ST3GAL3 is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates. The encoded protein is normally found in the Golgi apparatus but can be proteolytically processed to a soluble form. This protein is a member of glycosyltransferase family 29. Multiple transcript variants encoding several different isoforms have been found for this gene.The deduced 375-amino acid protein is 97% identical to the rat protein. SDS-PAGE analysis showed expression of an 80-kD protein having sialyltransferase activity. Northern blot analysis revealed wide expression of a 2.7-kb transcript with abundant expression in skeletal muscle and high expression in fetal tissue but low expression in placenta.