A strong non-equilibrium bound for sorting of crosslinkers on growing biopolymers

Yuqing Qiu; Michael Nguyen; Glen M. Hocky; Aaron R. Dinner; Suriyanarayanan Vaikuntanathan

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arXiv · 2012.11588

A strong non-equilibrium bound for sorting of crosslinkers on growing biopolymers

Yuqing Qiu·Michael Nguyen·Glen M. Hocky·Aaron R. Dinner·Suriyanarayanan Vaikuntanathan

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Abstract

Understanding the role of non-equilibrium driving in self-organization is crucial for developing a predictive description of biological systems, yet it is impeded by their complexity. The actin cytoskeleton serves as a paradigm for how equilibrium and non-equilibrium forces combine to give rise to self-organization. Motivated by recent experiments that show that actin filament growth rates can tune the morphology of a growing actin bundle crosslinked by two competing types of actin binding proteins, we construct a minimal model for such a system and show that the dynamics are subject to a set of thermodynamic constraints that relate the non-equilibrium driving, bundle morphology, and molecular fluxes. The thermodynamic constraints reveal the importance of correlations between these molecular fluxes, and offer a route to estimating microscopic driving forces from microscopy experiments.

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Yuqing Qiu, Michael Nguyen, Glen M. Hocky, Aaron R. Dinner, Suriyanarayanan Vaikuntanathan. 2020-12-21. A strong non-equilibrium bound for sorting of crosslinkers on growing biopolymers. https://arxiv.org/abs/2012.11588

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