Recombinant Human GalNAc-T3 (Polypeptide N-acetylgalactosaminyltransferase 3), soluble fragment
Polypeptide N-acetylgalactosaminyltransferase 3 (GalNAc-T3) catalyzes the transfer of N-acetylgalactosamine (GalNAc) from UDP-GalNAc to the hydroxyl group of serine and threonine residues (1). Twenty GalNAc-T genes have been identified in humans and most have been shown to represent active GalNAc-Ts. All isoforms are type II transmembrane proteins, with different but partly overlapping substrate preferences (2). The GalNAc-Ts control the initiation of mucin-type O-linked glycosylation and determine the location and density of O-glycans in a protein (2). Addition of GalNAc to an unglycosylated Ser/Thr residue creates the Tn antigen GalNAcα1-S/T, and subsequent addition of sialic acid by ST6GalNAc-I forms the cancer associated STn antigen (3). GalNAc-T3 is highly expressed in pancreas and testis, and weakly expressed in a few other organs such as placenta (1). The expression levels of GalNAc-T3 were found to be upregulated in highly differentiated types of adenocarcinoma cell lines as opposed to less differentiated types (4). Overexpression of GalNAc-T3 has also been found to promote pancreatic cancer cell growth (5). Mutations in GalNAc-T3 were found to be involved in familial tumoral calcinosis, which may be mediated through glycosylation of fibroblast growth factor 23, protecting it from proteolytic cleavage (6,7). GalNAc-T3 has a preference for mono- or diglycosylated substrates (8).
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Catalog #: SBH-003- GalNAc-T3
Source : Insect Cells, Uniprot Accession # Q14435
Formulation: Sterile filtered solution in 25mM Tris pH7.5 and 150mM NaCl, at a stock concentration of 466 ug/mL.
Stability: Stable for 4 weeks at 4C. Stable for 6 months at -80C. Avoid repeated freeze-thaw cycles.
Purity: Greater than 95% by SDS-PAGE.
Enzymatic Activity: Measured by transfer of N-acetylgalatosamine (GalNac) from UDP-Gal to the peptide EA2 (AnaSpec Inc, Catalog # 63841), as measured with a phosphatase-coupled assay (R&D Systems EA001). Coupling assay reactions contained: 50mM Tris pH 7.5, 2mM MnCl2, 0.5mM UDP-GalNAc, 0.25mM EA2, 4ug/mL ENTPD3/CD39L3, and 6ug/mL GalNAc-T3 (serially diluted 1:2 for 3pts). Incubated at 37ºC for 30min. >500pmol/min/ug.
Pubmed Link: GalNAc-T3 Human
Usage: For research only. Not for use in diagnostic or therapeutic procedures.
Country of Origin: USA