A versatile framework for simulating the dynamic mechanical structure of cytoskeletal networks

Abstract

Computer simulations can aid in understanding how collective materials properties emerge from interactions between simple constituents. Here, we introduce a coarse-grained model that enables simulation of networks of actin filaments, myosin motors, and crosslinking proteins at biologically relevant time and length scales. We demonstrate that the model qualitatively and quantitatively captures a suite of trends observed experimentally, including the statistics of filament fluctuations, mechanical responses to shear, motor motilities, and network rearrangements. We use the simulation to predict the viscoelastic scaling behavior of crosslinked actin networks, characterize the trajectories of actin in a myosin motility assay, and develop order parameters to measure contractility of a simulated actin network. The model can thus serve as a platform for interpretation and design of cytoskeletal materials experiments, as well as for further development of simulations incorporating active elements.

26 pages, 7 figures

References in corpus (4)

• Elasticity of Stiff Polymer Networks
• Collective Langevin Dynamics of Flexible Cytoskeletal Fibers
• Active contractility in actomyosin networks
• Scaling laws for the response of nonlinear elastic media with implications for cell mechanics

Cited by in corpus (12)

• Minimal coarse-grained models for molecular self-organisation in biology
• Design principles for selective self-assembly of active networks
• Towards the cellular-scale simulation of motor-driven cytoskeletal assemblies
• A Coarse-Grained Simulation Model for Self-Assembly of Liquid Droplets Featuring Explicit Mobile Binders
• Actin reorganization throughout the cell cycle mediated by motor proteins
• How crosslink numbers shape the large-scale physics of cytoskeletal materials
• Segmental Lennard-Jones Interactions for Semi-flexible Polymer Networks
• Pattern formation and the mechanics of a motor-driven filamentous system confined by rigid membranes
• Structural features and nonlinear rheology of self-assembled networks of cross-linked semiflexible polymers
• Differential cellular contractility as a mechanism for stiffness sensing
• Compression-induced continuous phase transition in the buckling of a semiflexible filament for two and three dimensions
• A theory for coexistence and selection of branched actin networks in a shared and finite pool of monomers