Mechanical force generation by G proteins.

Ioan Kosztin; Robijn Bruinsma; Paul O'Lague; Klaus Schulten

doi:10.1073/pnas.052209199

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PubMed · 11904419

Mechanical force generation by G proteins.

Ioan Kosztin·Robijn Bruinsma·Paul O'Lague·Klaus Schulten

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Abstract

GTP-hydrolyzing G proteins are molecular switches that play a critical role in cell signaling processes. Here we use molecular dynamics simulations to show that Ras, a monomeric G protein, can generate mechanical force upon hydrolysis. The generated force levels are comparable to those produced by ATP-hydrolyzing motor proteins, consistent with the structural similarities of the catalytic region of motor proteins and G proteins. The force transduction mechanism is based on an irreversible structural change, produced by the hydrolysis, which triggers thermal switching between force-generating substates through changes in the configurational space of the protein.

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Computer Simulation Guanosine Diphosphate Guanosine Triphosphate Humans Hydrolysis Kinetics Models, Molecular Molecular Motor Proteins Protein Conformation Proto-Oncogene Proteins p21(ras)Signal Transduction Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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Ioan Kosztin, Robijn Bruinsma, Paul O'Lague, Klaus Schulten. 2002-03-19. Mechanical force generation by G proteins.. https://doi.org/10.1073/pnas.052209199

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