Mechanical response of active gels

Abstract

We study a model of an active gel of cross-linked semiflexible filaments with additional active linkers such as myosin II clusters. We show that the coupling of the elasticity of the semiflexible filaments to the mechanical properties of the motors leads to contractile behavior of the gel, in qualitative agreement with experimental observations. The motors, however, soften the zero frequency elastic constant of the gel. When the collective motor dynamics is incorporated in the model, a stiffening of the network at high frequencies is obtained. The frequency controlling the crossover between low and high frequency network elasticity is estimated in terms of microscopic properties of motors and filaments, and can be as low as 10^(-3)Hz.

6 pages, 3 figures

References in corpus (5)

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• Organization and instabilities of entangled active polar filaments
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Cited by in corpus (20)

• Modeling semiflexible polymer networks
• Molecular motors robustly drive active gels to a critically connected state
• Structure formation in active networks
• Contractile units in disordered actomyosin bundles arise from F-actin buckling
• Actively stressed marginal networks
• Instabilities and Oscillations in Isotropic Active Gels
• Role of turn-over in active stress generation in a filament network
• Oriented Active Solids
• Design principles for selective self-assembly of active networks
• Substrate rigidity deforms and polarizes active gels
• Controlling cell-matrix traction forces by extracellular geometry
• Geometrical origins of contractility in disordered actomyosin networks
• Stress reorganisation and response in active solids
• Fluidization and Active Thinning by Molecular Kinetics in Active Gels
• Force-extension relation of cross-linked anisotropic polymer networks
• Maximal fluctuations of confined actomyosin gels: dynamics of the cell nucleus
• Tension-induced binding of semiflexible biopolymers
• Elasticity of a semiflexible filament with a discontinuous tension due to a cross-link or a molecular motor
• Active biopolymer networks generate scale-free but euclidean clusters
• A group theoretical approach to elasticity under constraints and predeformations