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bioRxiv · 10.1101/181347

A "Tug of War" maintains a dynamic protein-membrane complex: MD simulations of C-Raf RBD-CRD bound to K-Ras4B at an anionic membrane

LI, Z.·Srivastava, P. P.·Buck, M.
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Abstract

Association of Raf kinase with activated Ras triggers downstream signaling cascades, towards regulating transcription in the cells nucleus. Dysregulation of Ras: Raf signaling stimulates cancers. We investigate the C-Raf RBD and CRD regions when bound to oncogenic K-Ras4B at the membrane. All-atom molecular dynamics simulations suggest that the membrane plays an integral role in regulating the configurational ensemble of the complex. Remarkably, the complex samples a few states dynamically, reflecting a competition between C-Raf CRD and K-Ras4B- membrane interactions. This competition arises because the interaction between the RBD and K-Ras is strong and the linker between the RBD and CRD is short. This study reveals a mechanism that maintains a modest binding for the overall complex at the membrane to facilitate fast signaling processes. It is likely a common mechanism for other multi-protein, if not multidomain proteins at membranes.

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LI, Z., Srivastava, P. P., Buck, M.. 2017-08-27. A "Tug of War" maintains a dynamic protein-membrane complex: MD simulations of C-Raf RBD-CRD bound to K-Ras4B at an anionic membrane. https://doi.org/10.1101/181347

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