Rabbit polyclonal antibody to PEBP1

Raf kinase inhibitor protein (RKIP) is a cytosolic protein that was initially characterized as a phosphatidylethanolamine~binding protein (PBP) expressed in brain tissue and secreted from testis fluid. In addition, RKIP was identified by yeast two~hybrid screening of human T cell libraries directed at identifying proteins that associate with the BXB kinase domain of the serine/threonine kinase, Raf~1. Subsequent in vitro and in vivo studies indicate that RKIP binds to both the active and inactive forms of Raf~1 and thereby regulates the signaling cascade of the MAP kinase pathway. The specific association of RKIP with kinase~active Raf~1 competitively inhibits the binding and activation of the Raf~1 substrate MEK. RKIP, in turn, affects downstream MAP kinase signaling by decreasing the activation of MEK effector proteins, including ERK1 and ERK2, and the subsequent induction of AP~1 mediated transcription.