Anti-RMP (Unconventional Prefoldin RPB5 Interactor, RNA Polymerase II Subunit 5-mediating Protein, P

RMP (RPB5-Mediating Protein), also known as URI (Unconventional prefoldin RBP5 Interactor), was recently described as an unconventional member of the prefoldin (PFD) family of chaperones that are involved in actin and tubulin folding (1-4). Like conventional members of the a-class of PFDs, RMP contains N- and C-terminal a-helical coiled-coil structures connected by two B hairpins. In addition, RMP possesses a RPB5-binding segment and a long C-terminal acidic segment. It is posited that RMP exists as a component of a macromolecular complex within human cells and functions as a molecular scaffold to assemble a PFD complex containing other PFDs and proteins with functions in transcription and ubiquitination. Indeed, evidence is provided that RMP negatively modulates RNA polymerase II-dependent transcription by binding to TFIIF (5) and RBP5 (6) and is involved in mTOR signaling by coordinating the regulation of nutrient availability with gene expression (1). In accord with its ability to coordinate gene expression with nutrient availability, RMP was most recently shown to be a mitochondrial substrate of S6K1. S6K1-mediated phosphorylation of RMP at Ser371 triggers a series of biochemical events that constitute a negative feedback loop, in part, aimed at restraining S6K1 survival signaling and ensuring that the mitochondrial threshhold for apoptosis corresponds to availability of nutrients and growth factors (7). Applications: Suitable for use in Western Blot and Immunoprecipitation. Other applications not tested. Recommended Dilution: Western Blot: 1:1000, incubate membrane with diluted antibody in 5% BSA, 1X TBS, 0.1% Tween-20 at 4°C with gentle shaking, overnight., Immunoprecipitation: 1:50, Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.