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Random bursts determine dynamics of active filaments.

ABSTRACT: Constituents of living or synthetic active matter have access to a local energy supply that serves to keep the system out of thermal equilibrium. The statistical properties of such fluctuating active systems differ from those of their equilibrium counterparts. Using the actin filament gliding assay as a model, we studied how nonthermal distributions emerge in active matter. We found that the basic mechanism involves the interplay between local and random injection of energy, acting as an analog of a thermal heat bath, and nonequilibrium energy dissipation processes associated with sudden jump-like changes in the system's dynamic variables. We show here how such a mechanism leads to a nonthermal distribution of filament curvatures with a non-Gaussian shape. The experimental curvature statistics and filament relaxation dynamics are reproduced quantitatively by stochastic computer simulations and a simple kinetic model.

SUBMITTER: Weber CA

PROVIDER: S-EPMC4553809 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Random bursts determine dynamics of active filaments.

Weber Christoph A CA Suzuki Ryo R Schaller Volker V Aranson Igor S IS Bausch Andreas R AR Frey Erwin E

Proceedings of the National Academy of Sciences of the United States of America 20150810 34

Constituents of living or synthetic active matter have access to a local energy supply that serves to keep the system out of thermal equilibrium. The statistical properties of such fluctuating active systems differ from those of their equilibrium counterparts. Using the actin filament gliding assay as a model, we studied how nonthermal distributions emerge in active matter. We found that the basic mechanism involves the interplay between local and random injection of energy, acting as an analog ...[more]

PMID: 26261319

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