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arXiv · 2111.08677

Thermodynamic Control of Activity Patterns in Cytoskeletal Networks

Alexandra Lamtyugina·Yuqing Qiu·Étienne Fodor·Aaron R. Dinner·Suriyanarayanan Vaikuntanathan
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Abstract

We aim to identify the control principles governing the adaptable formation of non-equilibrium structures in actomyosin networks. We build a phenomenological model and predict that biasing the energy dissipated by molecular motors should effectively renormalize the motor-mediated interactions between actin filaments. Indeed, using methods from large deviation theory, we demonstrate that biasing energy dissipation is equivalent to modulating the motor rigidity and results in an aster-to-bundle transition. From the simulation statistics, we extract a relation between the biasing parameter and the corresponding normalized motor rigidity. This work elucidates the relationship between energy dissipation, effective interactions, and pattern formation in active biopolymer networks, providing a control principle of cytoskeletal structure and dynamics.

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Alexandra Lamtyugina, Yuqing Qiu, Étienne Fodor, Aaron R. Dinner, Suriyanarayanan Vaikuntanathan. 2021-11-16. Thermodynamic Control of Activity Patterns in Cytoskeletal Networks. https://doi.org/10.1103/physrevlett.129.128002

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