ST6GALNAC6

ST6GALNAC6 belongs to a family of sialyltransferases that modify proteins and ceramides on the cell surface to alter cell-cell or cell-extracellular matrix interactions (Tsuchida et al., 2003 [PubMed 12668675]).

Full Name

ST6 N-Acetylgalactosaminide Alpha-2,6-Sialyltransferase 6

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).

Biological Process

Biological Process cell-cell recognition1 PublicationIC:BHF-UCL
Biological Process ganglioside biosynthetic processISS:BHF-UCL
Biological Process glycoprotein metabolic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process glycosphingolipid metabolic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process glycosylceramide metabolic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process oligosaccharide biosynthetic processBy SimilarityISS:BHF-UCL
Biological Process oligosaccharide metabolic processManual Assertion Based On ExperimentIBA:GO_Central
Biological Process protein glycosylationIEA:InterPro

Cellular Location

Golgi apparatus membrane

Topology

Cytoplasmic: 1-43
Helical: 44-64
Lumenal: 65-333