Receptor-type tyrosine-protein phosphatase beta or VE-PTP is an enzyme specifically expressed in endothelial cells that in humans is encoded by the PTPRBgene.[1][2]
VE-PTP is a member of the classical protein tyrosine phosphatase (PTP) family. The deletion of the gene in mouse models was shown to be embryonically lethal,[3] thus indicating that it is important for vasculogenesis and blood vessel development. In addition, it was shown to participate in adherens junctions complex and regulate vascular permeability.[4][5] Recently, Soni et al. have shown that tyrosine phosphorylation of VE-PTP via Pyk2 kinase downstream of STIM1-induced calcium entry mediates disassembly of the endothelial adherens junctions.[5]
Interactions
VE-PTP contains an extracellular domain composed of multiple fibronectin type_III repeats, a single transmembrane segment and one intracytoplasmic catalytic domain, thus belongs to R3 receptor subtype PTPs.
The extracellular region was shown to interact with the angiopoietin receptor Tie-2[2] and with the adhesion protein VE-cadherin.[5][6]
VE-PTP was also found to interact with Grb2 and plakoglobin through its cytoplasmatic domain.
↑ 5.05.15.2Soni D, Regmi SC, Wang DM, DebRoy A, Zhao YY, Vogel SM, Malik AB, Tiruppathi C (Apr 2017). "Pyk2 Phosphorylation of VE-PTP Downstream of STIM1 induced Ca2+ entry Regulates Disassembly of Adherens Junctions". American Journal of Physiology. Lung Cellular and Molecular Physiology: ajplung.00008.2017. doi:10.1152/ajplung.00008.2017. PMID28385807.
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Harder KW, Anderson LL, Duncan AM, Jirik FR (1993). "The gene for receptor-like protein tyrosine phosphatase (PTPRB) is assigned to chromosome 12q15→q21". Cytogenet. Cell Genet. 61 (4): 269–70. doi:10.1159/000133419. PMID1486802.
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