ST3GAL4

Synthesis of alpha-2,3-linked sialic acid to Gal(beta-1,3)GalNAc is mediated by at least 3 distinct beta-galactoside alpha-2,3-sialyltransferases (EC 2.4.99.4), including ST3GAL4. In contrast, only a single gene encodes the beta-galactoside alpha-2,6-sialyltransferase (EC 2.4.99.1), ST6GAL1 (MIM 109675) (Chang et al., 1995 [PubMed 7655169]).[supplied by OMIM

Full Name

ST3 beta-galactoside alpha-2,3-sialyltransferase 4

Function

A beta-galactoside alpha2-3 sialyltransferase involved in terminal sialylation of glycoproteins and glycolipids (PubMed:8288606, PubMed:8611500).
Catalyzes the transfer of sialic acid (N-acetyl-neuraminic acid; Neu5Ac) from the nucleotide sugar donor CMP-Neu5Ac onto acceptor Galbeta-(1->3)-GalNAc- and Galbeta-(1->4)-GlcNAc-terminated glycoconjugates through an alpha2-3 linkage (PubMed:8288606, PubMed:8611500).
Plays a major role in hemostasis. Responsible for sialylation of plasma VWF/von Willebrand factor, preventing its recognition by asialoglycoprotein receptors (ASGPR) and subsequent clearance. Regulates ASGPR-mediated clearance of platelets (By similarity).
Participates in the biosynthesis of the sialyl Lewis X epitopes, both on O- and N-glycans, which are recognized by SELE/E-selectin, SELP/P-selectin and SELL/L-selectin. Essential for selectin-mediated rolling and adhesion of leukocytes during extravasation (PubMed:25498912).
Contributes to adhesion and transendothelial migration of neutrophils likely through terminal sialylation of CXCR2 (By similarity).
In glycosphingolipid biosynthesis, sialylates GM1 and GA1 gangliosides to form GD1a and GM1b, respectively (PubMed:8288606).
Metabolizes brain c-series ganglioside GT1c forming GQ1c (By similarity).
Synthesizes ganglioside LM1 (IV3Neu5Ac-nLc4Cer), a major structural component of peripheral nerve myelin (PubMed:8611500).

Biological Process

Biological Process cognitionManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process glycolipid biosynthetic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process glycoprotein biosynthetic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process keratan sulfate biosynthetic processTAS:Reactome
Biological Process lipid glycosylationManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process O-glycan processingTAS:Reactome
Biological Process oligosaccharide biosynthetic processManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process positive regulation of blood coagulationISS:UniProtKB
Biological Process positive regulation of leukocyte tethering or rollingManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process protein glycosylationManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process protein sialylationManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process sialylationManual Assertion Based On ExperimentIDA:BHF-UCL
Biological Process viral protein processingTAS:Reactome

Cellular Location

Golgi apparatus, Golgi stack membrane
Secreted
Membrane-bound form in trans cisternae of Golgi. Secreted into the body fluid.

Topology

Cytoplasmic: 1-8
Helical: 9-26
Lumenal: 27-333

PTM

The soluble form derives from the membrane form by proteolytic processing.