Contraction of cross-linked actomyosin bundles.
Cross-linked actomyosin bundles retract when severed in vivo by laser ablation, or when isolated from the cell and micromanipulated in vitro in the presence of ATP. We identify the timescale for contraction as a viscoelastic time τ, where the viscosity is due to (internal) protein friction. We obtain an estimate of the order of magnitude of the contraction time τ ≈ 10-100 s, consistent with available experimental data for circumferential microfilament bundles and stress fibers. Our results are supported by an exactly solvable, hydrodynamic model of a retracting bundle as a cylinder of isotropic, active matter, from which the order of magnitude of the active stress is estimated.
WPI Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. yoshinaga@wpi-aimr.tohoku.ac.jp
Natsuhiko
N
Yoshinaga
Philippe
P
Marcq
D008841:Actin Cytoskeleton / Q000737:chemistry* / Q000378:metabolism; D000205:Actomyosin / Q000737:chemistry* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D003198:Computer Simulation; D004548:Elasticity; D006801:Humans; D057446:Hydrodynamics; D007700:Kinetics; D008846:Micromanipulation; D008954:Models, Biological; D022502:Stress Fibers / Q000737:chemistry* / Q000378:metabolism; D013314:Stress, Mechanical; D014783:Viscosity
D000255:Adenosine Triphosphate; D000205:Actomyosin