PTP1B Antibody – Mouse Monoclonal

The protein encoded by this gene is the founding member of the protein tyrosine phosphatase (PTP) family, which was isolated and identified based on its enzymatic activity and amino acid sequence. PTPs catalyze the hydrolysis of the phosphate monoesters specifically on tyrosine residues. Members of the PTP family share a highly conserved catalytic motif, which is essential for the catalytic activity. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation. This PTP has been shown to act as a negative regulator of insulin signaling by dephosphorylating the phosphotryosine residues of insulin receptor kinase. This PTP was also reported to dephosphorylate epidermal growth factor receptor kinase, as well as JAK2 and TYK2 kinases, which implicated the role of this PTP in cell growth control, and cell response to interferon stimulation. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2013]

PTP1B: a non-receptor phospho-tyrosine protein phosphatase which acts as a regulator of endoplasmic reticulum unfolded protein response. Mediates dephosphorylation and inactivation of PERK. May play an important role in CKII- and p60c-src-induced signal transduction cascades. May regulate the EFNA5-EPHA3 signaling pathway which modulates cell reorganization and cell-cell repulsion. Negatively regulates insulin signaling by dephosphorylating the phosphotyrosine residues of insulin receptor. Also reported to dephosphorylate integrin, epidermal growth factor receptor, JAK2 and TYK2, regulating cell growth control and the cellular response to interferon. May regulate the hepatocyte growth factor receptor signaling pathway through dephosphorylation of MET. PTP1B knockout mice show resistance to dietary weight gain and enhanced insulin sensitivity, suggesting a possible role in treatment of obesity as well as type 2 diabetes.

Protein type: EC 3.1.3.48; Motility/polarity/chemotaxis; Phosphatase; Protein phosphatase, tyrosine (non-receptor)

Chromosomal Location of Human Ortholog: 20q13.13

Cellular Component: cell-cell adherens junction; cytosol; early endosome; endoplasmic reticulum; plasma membrane

Molecular Function: enzyme binding; ephrin receptor binding; protein binding; protein kinase binding; protein tyrosine phosphatase activity; receptor tyrosine kinase binding; zinc ion binding

Biological Process: actin cytoskeleton reorganization; negative regulation of MAP kinase activity; negative regulation of signal transduction; negative regulation of vascular endothelial growth factor receptor signaling pathway; protein amino acid dephosphorylation; regulation of endocytosis; regulation of intracellular protein transport; regulation of signal transduction; unfolded protein response; unfolded protein response, activation of signaling protein activity

Disease: Diabetes Mellitus, Noninsulin-dependent