Abstract

The actin cytoskeleton is an active semi-flexible polymer network whose non-equilibrium properties coordinate both stable and contractile behaviors to maintain or change cell shape. While myosin motors drive the actin cytoskeleton out-of-equilibrium, the role of myosin-driven active stresses in the accumulation and dissipation of mechanical energy is unclear. To investigate this, we synthesize an actomyosin material in vitro whose active stress content can tune the network from stable to contractile. Each increment in activity determines a characteristic spectrum of actin filament fluctuations which is used to calculate the total mechanical work and the production of entropy in the material. We find that the balance of work and entropy does not increase monotonically and the entropy production rate is maximized in the non-contractile, stable state of actomyosin. Our study provides evidence that the origins of entropy production and activity-dependent dissipation relate to disorder in the molecular interactions between actin and myosin.

Details

Title
Entropy production rate is maximized in non-contractile actomyosin
Author
Seara, Daniel S 1   VIAFID ORCID Logo  ; Yadav, Vikrant 2 ; Linsmeier, Ian 2 ; A Pasha Tabatabai 2 ; Oakes, Patrick W 3   VIAFID ORCID Logo  ; Ali Tabei, S M 4 ; Banerjee, Shiladitya 5 ; Murrell, Michael P 6 

1  Department of Physics, Yale University, New Haven, CT, USA; Systems Biology Institute, Yale University, West Haven, CT, USA 
2  Systems Biology Institute, Yale University, West Haven, CT, USA; Department of Biomedical Engineering, Yale University, New Haven, CT, USA 
3  Department of Physics & Astronomy, and Department of Biology, University of Rochester, Rochester, NY, USA 
4  Physics Department, University of Northern Iowa, Cedar Falls, IA, USA 
5  Department of Physics and Astronomy, Institute for the Physics of Living Systems, University College London, London, UK 
6  Department of Physics, Yale University, New Haven, CT, USA; Systems Biology Institute, Yale University, West Haven, CT, USA; Department of Biomedical Engineering, Yale University, New Haven, CT, USA 
Pages
1-10
Publication year
2018
Publication date
Nov 2018
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41467-018-07413-5
ProQuest document ID
2137122198
Copyright
© 2018. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.