Constriction of actin rings by passive crosslinkers
arXiv:2203.04260 · doi:10.1103/PhysRevLett.131.038401
Abstract
In many organisms, cell division is driven by the constriction of a cytokinetic ring, which consists of actin filaments and crosslinking proteins. While it has long been believed that the constriction is driven by motor proteins, it has recently been discovered that passive crosslinkers that do not turn over fuel are able to generate enough force to constrict actin filament rings. To study the ring constriction dynamics, we develop a model that includes the driving force of crosslinker condensation and the opposing forces of friction and filament bending. We analyze the constriction force as a function of ring topology and crosslinker concentration, and predict forces that are sufficient to constrict an unadorned plasma membrane. Our model also predicts that actin-filament sliding arises from an interplay between filament rotation and crosslinker hopping, producing frictional forces that are low compared to those of crosslinker-mediated microtubule sliding.
arXiv comment23 pages, 14 figures, resubmitted to PRL with analysis of dynamics included
References in corpus (6)
- The deal.II finite element library: design, features, and insights
- Twirling of actin by myosins II and V observed via polarized TIRF in a modified gliding assay
- Twirling motion of actin filaments in gliding assays with non-processive myosin motors
- Motor-free Contractility in Active Gels
- Diffusible crosslinkers cause superexponential friction forces
- Direct and simultaneous measurement of the stiffness and internal friction of a single folded protein