Invitrogen™ PTPRK Polyclonal Antibody

Protein tyrosine phosphatases, or PTPs, are type I transmembrane proteins, membrane associated proteins or proteins localized in nuclei. Examples of transmembrane PTPs are LAR, PTP alpha, PTP beta, PTP gamma, PTP delta, PTP epsilon, PTP zeta, PTPk and PTP-mu. Transmembrane PTPs play diverse roles during development and in adult tissues. Immunodepletion studies have suggested LAR to be a regulator of Insulin receptor phosphorylation. PTP alpha activity is increased twofold in response to phorbol ester stimulation, resulting in serine phosphorylation either directly or indirectly by members of the PKC family. Overexpression of v-H-ras and Neu, but not Myc or Int2, in mammary tumors has been shown to induce PTP epsilon expression. An alternative splicing event leads to a nervous tissue-specific chondroitin sulfate proteoglycan called phosphacan, which represents the amino terminal portion of PTP zeta. PTPk and PTP-mu share a conserved amino terminal 160 amino acid MAM domain which facilitates homophilic binding. PTP-mu localizes to points of cell contact and may be involved in regulating the assembly and disassembly of cadherin/catenin complexes in vivo.