The protein encoded by this gene is a member of the protein tyrosine phosphatase PTP family. Protein tyrosine phosphatases are protein enzymes that remove phosphate moieties from tyrosine residues on other proteins. Tyrosine kinases are enzymes that add phosphates to tyrosine residues, and are the opposing enzymes to PTPs. PTPs are known to be signaling molecules that regulate a variety of cellular processes including cell growth, differentiation, mitotic cycle, and oncogenic transformation.
The use of short interfering RNA siRNA from PTPkappa to reduce PTPkappa protein expression in epithelial cell lines, MCF10A, resulted in increased cell proliferation. The expression PTPkappa, on the contrary, showed decrease of proliferation in the ovary cells Chinese hamster. The mechanism proposed to explain the effects of PTPkappa on cell proliferation via PTPkappa of dephosphorylation of EGFR at tyrosines 1068 and 1173 directly. The decrease in the expression PTPkappa in the cells of SNO with PTPkappa siRNA increased EGFR phosphorylation. Thus, the hypothesis is that PTPkappa functions as a tumor suppressor gene by dephosphorylating and inactivating EGFR.
In addition, glycosylation of N-acetylglucosaminyltransferase-in GNT-in Was shown to reduce expression of full-length PTPkappa, likely via increasing its cleavage. This aberrant glycosylation has been shown that the increase in phosphorylation of EGFR on tyrosine 1068, likely because of reduced plasma membrane associated expression PTPkappa and hence reduced PTPkappa-mediated dephosphorylation of its membrane associated substrates, such as EGFR.
- include PTPRA, PTPRB, PTPRC, PTPRD, PTPRE, PTPRF, PTPRG, PTPRH, PTPRJ, PTPRK PTPRM, PTPRN, PTPRN2, PTPRO, PTPRQ, PTPRR, PTPRS, PTPRT, PTPRU, and PTPRZ
- EGFL6 MAMDC2 MAMDC4 MDGA1 MDGA2 MEP1A MEP1B NPNT NRP1 NRP2 PRSS7 PTPRK PTPRM PTPRO PTPRT PTPRU ZAN Bork P, Beckmann G 1993 An adhesive
- PHYHIPL PRLR PRODH2 PTPRB PTPRC PTPRD PTPRF PTPRG PTPRH PTPRJ PTPRK PTPRM PTPRO PTPRS PTPRT PTPRU PTPRZ1 PTPsigma PUNC RIMBP2 ROBO1
- PSG11 PSG11s PSG2 PSG3 PSG4 PSG5 PSG6 PSG7 PSG8 PSG9 PTGFRN PTK7 PTPRD PTPRK PTPRM PTPRS PTPsigma PUNC PVR PVRL1 PVRL2 PVRL4 RAGE SCN1B SDK1 SDK2 SEMA3A
- lambda, hPTP - J, PTPRO, and PTP psi. Other type R2B RPTPs include PTPRM, PTPRK and PTPRT. Analysis of the genomic structure of PCP - 2 suggests that it
- subfamily of RPTPs, which also includes the RPTPs PTPmu PTPRM PTPkappa PTPRK and PCP - 2 PTPRU Comparison of R2B cDNA sequences identified that PTPmu