ST6GAL1 Human

ST6 Beta-Galactosamide Alpha-2,6-Sialyltransferase 1, commonly referred to as ST6GAL1, is an enzyme that plays a crucial role in the modification of glycoproteins and glycolipids. This enzyme is part of the glycosyltransferase family 29 and is responsible for the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates, forming α2,6 linkages .

The ST6GAL1 gene is located on chromosome 3 in humans and encodes a type II membrane protein. This protein is typically found in the Golgi apparatus but can be processed into a soluble form . The human recombinant form of ST6GAL1 is expressed in human HEK 293 cells as a glycoprotein with a calculated molecular mass of 43.5 kDa, although it migrates as a ~50 kDa polypeptide on SDS-PAGE due to glycosylation .

ST6GAL1 is involved in the generation of cell-surface carbohydrate determinants and differentiation antigens such as HB-6, CD75, and CD76 . It catalyzes the formation of NeuAcα2,6-Gal linkages in N-linked glycans, which are essential for various biological processes, including cell-cell interactions, immune responses, and pathogen recognition .

ST6GAL1 shows a broad tissue distribution, with particularly high expression in the liver, lactating mammary gland, hematopoietic activated B cells, and a subset of T cells . Its deficiency can lead to a significant reduction in α2,6-sialylation in N-linked glycans, impacting various physiological and pathological processes .

Alterations in the expression or function of ST6GAL1 have been associated with several diseases, including large cell carcinoma with rhabdoid phenotype and colon adenocarcinoma . Additionally, ST6GAL1 is involved in early SARS-CoV-2 infection events and the biosynthesis of glycosphingolipids .

Human recombinant ST6GAL1 is widely used in research to study its role in glycosylation and its impact on various biological processes. It is also being explored as a potential target for therapeutic interventions in diseases where its activity is dysregulated .