Design principles for selective self-assembly of active networks

Abstract

Living cells dynamically modulate the local morphologies of their actin cytoskeletons to perform biological functions, including force transduction, intracellular transport, and cell division. A major challenge is to understand how diverse structures of the actin cytoskeleton are assembled from a limited set of molecular building blocks. Here we study the spontaneous self-assembly of a minimal model of cytoskeletal materials, consisting of semiflexible actin filaments, crosslinkers, and molecular motors. Using coarse-grained simulations, we demonstrate that by changing concentrations and kinetics of crosslinkers and motors we can generate three distinct structural phases of actomyosin assemblies: bundled, polarity-sorted, and contracted. We introduce new metrics to distinguish these structural phases and demonstrate their functional roles. We find that the binding kinetics of motors and crosslinkers can be tuned to optimize contractile force generation, motor transport, and mechanical response. By quantitatively characterizing the relationships between modes of cytoskeletal self-assembly, the resulting structures, and their functional consequences, our work suggests new principles for the design of active materials.

17 pages, 15 figures

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Cited by in corpus (7)

• Minimal coarse-grained models for molecular self-organisation in biology
• A Coarse-Grained Simulation Model for Self-Assembly of Liquid Droplets Featuring Explicit Mobile Binders
• Motor crosslinking augments elasticity in active nematics
• Uncovering the dynamic precursors to motor-driven contraction of active gels
• Thermodynamic Control of Activity Patterns in Cytoskeletal Networks
• Coarse-grained dynamics of transiently-bound fast linkers
• Quantifying Dissipation in Actomyosin Networks