ST6GALNAC6
Function
Transfers the sialyl group (N-acetyl-alpha-neuraminyl or NeuAc) from CMP-NeuAc onto glycoproteins and glycolipids, forming an alpha-2,6-linkage. Produces branched type disialyl structures by transfer of a sialyl group onto the GalNAc or GlcNAc residue inside backbone core chains having a terminal sialic acid with an alpha-2,3-linkage on Gal. ST6GalNAcVI prefers glycolipids to glycoproteins, predominantly catalyzing the biosynthesis of ganglioside GD1alpha from GM1b (PubMed:12668675, PubMed:17123352). Besides GMb1, MSGG and other glycolipids, it shows activity towards sialyl Lc4Cer generating disialyl Lc4Cer, which can lead to the synthesis of disialyl Lewis a (Le(a)), suggested to be a cancer-associated antigen (PubMed:12668675). Also has activity toward GD1a and GT1b, and can generate DSGG (disialylgalactosylgloboside) from MSGG (monosialylgalactosylgloboside) (By similarity).
Sequence Similarities
Belongs to the glycosyltransferase 29 family.
Tissue Specificity
Expressed in kidney, in proximal tubule epithelial cells. Expressed in colon cell lines.
Cellular localization
- Golgi apparatus membrane
- Single-pass type II membrane protein
Alternative names
SIAT7F, UNQ708/PRO1359, ST6GALNAC6, ST6GalNAc VI, Sialyltransferase 7F, ST6GalNAcVI, hST6GalNAc VI, SIAT7-F