Heterogeneous nuclear ribonucleoprotein M associates with mTORC2 and regulates muscle differentiation.

摘要: Mammalian target of rapamycin (mTOR) plays a range crucial roles in cell survival, growth, proliferation, metabolism, and morphology. However, mTOR forms two distinct complexes, complex 1 2 (mTORC1 mTORC2), via association with series different components; this allows the complexes to execute their wide functions. This study explores further composition mTORC2 complex. Utilizing Rictor knock-out cells, immunoprecipitation mass spectrometry, novel associated protein, heterogeneous nuclear ribonucleoprotein M (hnRNP M), was identified. The between hnRNP verified using recombinant endogenous protein binding site found be within aa 1~532 M. presence significantly affects phosphorylation SGK1 S422, but not Akt S473, PKCα S657 PKCζ T560. Furthermore, also critical role muscle differentiation because knock-down either or C2C12 myoblasts reduced differentiation. decrease is able rescued by overexpression SGK S422D knockdown myoblasts. Taken together, we have identified Rictor/mTOR molecule, M, that signaling phosphorylate thus regulating