2009/06/04 by Andrej Vilfan
Biochemistry, Genetics and Molecular Biology · Medicine · Physics and Astronomy · #Cardiomyopathy and Myosin Studies #Micro and Nano Robotics #Microtubule and mitosis dynamics #cond-mat.soft #physics.bio-ph #q-bio.BM
paper · pdf · doi:10.1016/j.bpj.2009.06.008
published as Biophys. J. 97, 1130-1137 (2009) · 8 pages, 6 figures. Submitted to Biophysical Journal
arxiv created 2009/06/04 · openalex publication_date 2009/08/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a model study of gliding assays in which actin filaments are moved by non-processive myosin motors. We show that even if the power stroke of the motor protein has no lateral component, the filaments will rotate around their axis while moving over the surface. Notably, the handedness of this twirling motion is opposite from that of the actin filament structure. It stems from the fact that the gliding actin filament has "target zones" where its subunits point towards the surface and are therefore more accessible for myosin heads. Each myosin head has a higher binding probability before it reaches the center of the target zone than afterwards, which results in a left-handed twirling. We present a stochastic simulation and an approximative analytical solution. The calculated pitch of the twirling motion depends on the filament velocity (ATP concentration). It reaches about 400nm for low speeds and increases with higher speeds.