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Title: A strong nonequilibrium bound for sorting of cross-linkers on growing biopolymers
Understanding the role of nonequilibrium 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 nonequilibrium 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 cross-linked by two competing types of actin-binding proteins [S. L. Freedman et al. , Proc. Natl. Acad. Sci. U.S.A. 116, 16192–16197 (2019)], we construct a minimal model for such a system and show that the dynamics of a growing actin bundle are subject to a set of thermodynamic constraints that relate its nonequilibrium driving, 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.  more » « less
Award ID(s):
2011854
PAR ID:
10313808
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
38
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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