ST8SIA1

Gangliosides are membrane-bound glycosphingolipids containing sialic acid. Ganglioside GD3 is known to be important for cell adhesion and growth of cultured malignant cells. The protein encoded by this gene is a type II membrane protein that catalyzes the transfer of sialic acid from CMP-sialic acid to GM3 to produce gangliosides GD3 and GT3. The encoded protein may be found in the Golgi apparatus and is a member of glycosyltransferase family 29. Alternatively spliced transcript variants have been found for this gene.

Full Name

ST8 Alpha-N-Acetyl-Neuraminide Alpha-2,8-Sialyltransferase 1

Function

Catalyzes the addition of sialic acid in alpha 2,8-linkage to the sialic acid moiety of the ganglioside GM3 to form ganglioside GD3; gangliosides are a subfamily of complex glycosphinglolipds that contain one or more residues of sialic acid (PubMed:7937974, PubMed:8058740, PubMed:8195250, PubMed:8631981, PubMed:8706663, PubMed:18348864, PubMed:22885356).
Can catalyze the addition of a second alpha-2,8-sialic acid to GD3 to form GT3 (PubMed:8631981).
Can use GM1b, GD1a and GT1b as acceptor substrates to synthesize GD1c, GT1a and GQ1b respectively (PubMed:8706663).
Can synthesize unusual tetra- and pentasialylated lactosylceramide derivatives identified as GQ3 (II3Neu5Ac4-Gg2Cer) and GP3 (II3Neu5Ac5-Gg2Cer) in breast cancer cells (PubMed:22885356).

Biological Process

Biological Process carbohydrate metabolic processManual Assertion Based On ExperimentTAS:ProtInc
Biological Process cellular response to heatIEA:Ensembl
Biological Process epithelial cell proliferationIEA:Ensembl
Biological Process glycosphingolipid biosynthetic processManual Assertion Based On ExperimentTAS:ProtInc
Biological Process N-glycan processingManual Assertion Based On ExperimentIBA:GO_Central
Biological Process oligosaccharide metabolic processManual Assertion Based On ExperimentIBA:GO_Central
Biological Process positive regulation of epithelial cell proliferationIEA:Ensembl
Biological Process protein glycosylationManual Assertion Based On ExperimentIBA:GO_Central

Cellular Location

Golgi apparatus membrane

Topology

Cytoplasmic: 1-29
Helical: 30-48
Lumenal: 49-356