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This content will become publicly available on June 2, 2023

Title: Computational studies of the principle of dynamic-change-driven protein interactions
Dynamic allostery emphasizes a role of entropy change manifested as a sole change in protein fluctuations without structural changes. This kind of entropy-driven effect remains largely understudied. The most significant examples involve protein-ligand interactions, leaving protein-protein interactions, which are critical in signaling and other cellular events, largely unexplored. Here we study an example of how protein-protein interaction (binding of Ras to the Ras binding domain [RBD] of the effector protein Raf) affects a subsequent protein association process (Ras dimerization) by quenching Ras internal motions through dynamic allostery. We also investigate the influence of point mutations or ambient temperature, respectively, on the protein dynamics and interaction of two other systems: in adenylate kinase (ADK) and in the EphA2 SAM:Ship2 SAM complex. Based on these examples, we postulate that there are different ways in which dynamic-change-driven protein interactions are manifested and that it is likely a general biological phenomenon.
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909 - 916
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National Science Foundation
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