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arXiv · 1807.10152

Morphological and dynamical properties of semiflexible filaments driven by molecular motors

Nisha Gupta·Abhishek Chaudhuri·Debasish Chaudhuri
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Abstract

We consider an explicit model of a semiflexible filament moving in two dimensions on a gliding assay of motor proteins, which attach to and detach from filament segments stochastically, with a detachment rate that depends on the local load experienced. Attached motor proteins move along the filament to one of its ends with a velocity that varies non-linearly with the motor protein extension. The resultant force on the filament drives it out of equilibrium. The distance from equilibrium is reflected in the end-to-end distribution, modified bending stiffness, and a transition to spiral morphology of the polymer. The local stress dependence of activity results in correlated fluctuations in the speed and direction of the center of mass leading to a series of ballistic-diffusive crossovers in its dynamics.

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Nisha Gupta, Abhishek Chaudhuri, Debasish Chaudhuri. 2019-05-22. Morphological and dynamical properties of semiflexible filaments driven by molecular motors. https://doi.org/10.1103/physreve.99.042405

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