Maximal fluctuations of confined actomyosin gels: dynamics of the cell nucleus

Abstract

We investigate the effect of stress fluctuations on the stochastic dynamics of an inclusion embedded in a viscous gel. We show that, in non-equilibrium systems, stress fluctuations give rise to an effective attraction towards the boundaries of the confining domain, which is reminiscent of an active Casimir effect. We apply this generic result to the dynamics of deformations of the cell nucleus and we demonstrate the appearance of a fluctuation maximum at a critical level of activity, in agreement with recent experiments [E. Makhija, D. S. Jokhun, and G. V. Shivashankar, Proc. Natl. Acad. Sci. U.S.A. 113, E32 (2016)].

12 pages, 5 figures

References in corpus (6)

• State-dependent diffusion: thermodynamic consistency and its path integral formulation
• Run-and-Tumble Dynamics of Self-Propelled Particles in Confinement
• Dynamics of Active Rouse Chains
• Mechanical response of active gels
• Geometrical origins of contractility in disordered actomyosin networks
• Soft inclusion in a confined fluctuating active gel

Cited by in corpus (4)

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