PTP epsilon: Lysates

PTP epsilon, an R4 receptor protein tyrosine phosphatase, is composed of a short extracellular and two cyplasmic protein phosphatase domains and has been shown to affect neuronal differentiation, endothelial cell growth, vascular development, and possibly mammary tumor development. It has been shown that the cytosolic form of PTP epsilon can be induced by IL-1 and TNF alpha in humans and is a negative regulator of IL-6- and LIF-induced Jak-STAT kinase signaling in rats. Four alternatively spliced protein isoforms have been documented for PTP epsilon: a membrane form, a cytosolic form, the p65 form, which results from translation using an internal initiation codon, and the p67 form, which results from a specific proteolytic cleavage of wild-type PTP epsilon. PTP epsilon expression has been documented in human vascular endothelial cells, astrocytoma cells, and in IW32 erythroleukemia overexpressing p53. PTP epsilon expression has been documented in animal brain, breast, ganglion, heart, kidney, liver, lung, nerve, spinal cord, spleen, testis, and vessel. The membrane and cytosolic forms of PTP epsilon show different tissue expression patterns. ESTs have been isolated from numerous human tissue libraries, including normal human blood, brain, testis, and thyroid, and cancerous human blood, brain, breast, colon, embryo, head/neck, pancreas, and skin.