RanBPM interacts with TβRI, TRAF6 and curbs TGF induced nuclear accumulation of TβRI

Transforming growth factor beta (TGF-beta), a cytoldne, and its receptors play a vital role during normal embryogenesis, cell proliferation, differentiation, apoptosis and migration. Ran-binding protein in the microtubule-organizing center (RanBPM) serves as a scaffold protein that has been shown to interact with many other proteins, such as MET, Axl/Sky, TRAF6, IFNR, TrKA and TricB in addition to p75NTR In the current study, we have identified RanBPM as a novel binding partner of T beta RI by yeast two-hybrid assay. The T beta RI and RanBPM association was confirmed by co-immunoprecipitation and GST pull-down experiments. Additionally, expression of RanBPM abrogated the interaction between T beta RI and TRAF6. Furthermore, RanBPM could depress TGF-beta induced TRAF6 ubiquitination, subsequent NF-KB signaling pathway, and block TGF-beta induced 113RI nuclear accumulation. Taken together, our results reveal that RanBPM may modulate TGF-beta-mediated downstream signaling and biological functions. (C) 2013 Published by Elsevier Inc.