ENPP3 Antibody – Mouse Monoclonal

The protein encoded by this gene belongs to a series of ectoenzymes that are involved in hydrolysis of extracellular nucleotides. These ectoenzymes possess ATPase and ATP pyrophosphatase activities and are type II transmembrane proteins. Expression of the related rat mRNA has been found in a subset of immature glial cells and in the alimentary tract. The corresponding rat protein has been detected in the pancreas, small intestine, colon, and liver. The human mRNA is expressed in glioma cells, prostate, and uterus. Expression of the human protein has been detected in uterus, basophils, and mast cells. [provided by RefSeq, Jul 2008]

Function: Cleaves a variety of phosphodiester and phosphosulfate bonds including deoxynucleotides, nucleotide sugars, and NAD

By similarity.

Catalytic activity: Hydrolytically removes 5'-nucleotides successively from the 3'-hydroxy termini of 3'-hydroxy-terminated oligonucleotides.A dinucleotide + H2O = 2 mononucleotides.

Cofactor: Binds 2 divalent metal cations per subunit

Probable.

Enzyme regulation: At low concentrations of ATP, a phosphorylated active site intermediate is formed which inhibits further ATP hydrolysis.

Subcellular location: Membrane; Single-pass type II membrane protein

Potential. Secreted. Note: Located to the apical surface in intestinal and kidney epithelial cells. Located to the cell surface of basophils, and to the apical plasma membrane of bile duct cells. Secreted in serum, and in lumen of epithelial cells. Ref.5 Ref.6

Tissue specificity: Expressed in bile ducts, prostate, uterus and colon. Exclusively expressed on basophils, mast cells and their progenitors. Ref.1 Ref.6

Induction: Up-regulated by stimulation by allergen or by cross-linking with IgE. The IgE-mediated activation is enhanced by tetradecanoyl phorbol acetate (TPA), a stimulator of the PKC pathway, and inhibited by the P13 kinase inhibitors, LY294002 and wortmannin. Up-regulated in invasive bile duct cancers. Ref.7

Post-translational modification: N-glycosylation is necessary for correct trafficking to the apical surface, but is not the apical targeting signal

By similarity.It has been suggested that the active SMB domain may be permitted considerable disulfide bond heterogeneity or variability, thus two alternate disulfide patterns based on 3D structures are described with 1 disulfide bond conserved in both.

Sequence similarities: Belongs to the nucleotide pyrophosphatase/phosphodiesterase family.Contains 2 SMB (somatomedin-B) domains.

Sequence caution: The sequence AAD05192.1 differs from that shown. Reason: Erroneous gene model prediction.