title: Role of Turnover in Active Stress Generation in a Filament Network.
abstract: We study the effect of turnover of cross-linkers, motors, and filaments on the generation of a contractile stress in a network of filaments connected by passive cross-linkers and subjected to the forces exerted by molecular motors. We perform numerical simulations where filaments are treated as rigid rods and molecular motors move fast compared to the time scale of an exchange of cross-linkers. We show that molecular motors create a contractile stress above a critical number of cross-linkers. When passive cross-linkers are allowed to turn over, the stress exerted by the network vanishes due to the formation of clusters. When both filaments and passive cross-linkers turn over, clustering is prevented and the network reaches a dynamic contractile steady state. A maximum stress is reached for an optimum ratio of the filament and cross-linker turnover rates. Taken together, our work reveals conditions for stress generation by molecular motors in a fluid isotropic network of rearranging filaments.
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany.|Fachbereich Physik, Freie Universität Berlin, Berlin 14195, Germany.|Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hiraiwa
authors.affiliation: Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, 01187 Dresden, Germany.|The Francis Crick Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, United Kingdom.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Salbreux
mesh_terms: D001696:Biomechanical Phenomena; D003198:Computer Simulation; D003599:Cytoskeleton; D008954:Models, Biological; D020409:Molecular Motor Proteins; D009119:Muscle Contraction
chemical_list: D020409:Molecular Motor Proteins