This talk focuses on active mechanics of a cortical cytoskeleton, which is a network structure consisting of actin and myosin filaments and crosslinker proteins located underneath the cell membrane . Mechanical properties of a cortical cytoskeleton govern not only cell‘s resistances to deformation but also contractility induced by the motor protein, myosin. Motor-induced contractile stress in a cortical cytoskeleton plays crucial roles in dynamic cellular behaviors, such as cytokinesis and cell migration.
In this talk, I would like to explain our theoretical work on stress generation in a cortical cytoskeleton. I will propose a mechanical model of motor-induced stress in an isotropic actomyosin network with crosslinkers and share the results of the model about motor-induced contractility. In particular, since a cortical cytoskeleton in a living cell should be flowable, we study the case of fluidic networks, in which there are only few amount of crosslinkers and/or network elements can undergo stochastic turnover processes . We found that a finite amount of crosslinkers is significant for motor-induced contractility . We also investigated how turnover of crosslinkers and actin filaments influences motor-induced stress .