Motor-free Contractility in Active Gels

Abstract

Animal cells form contractile structures to promote various functions, from cell motility to cell division. Force generation in these structures is often due to molecular motors such as myosin that require polar substrates for their function. Here, we propose a motor-free mechanism that can generate contraction in biopolymer networks without the need for polarity. This mechanism is based on active binding/unbinding of crosslinkers that breaks the principle of detailed balance, together with the asymmetric force-extension response of semiflexible biopolymers. We find that these two ingredients can generate steady state contraction via a non-thermal, ratchet-like process. We calculate the resulting force-velocity relation using both coarse-grained and microscopic models.

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Cited by in corpus (6)

• Odd viscosity in active matter: microscopic origin and 3D effects
• Thermodynamics of active field theories: Energetic cost of coupling to reservoirs
• Lorentz Reciprocal Theorem in Fluids with Odd Viscosity
• Non-linear stress relaxation of transient-crosslinked biopolymer networks
• Second Law of Thermodynamics without Einstein Relation
• Constriction of actin rings by passive crosslinkers