Actomyosin-driven left-right asymmetry: from molecular torques to chiral self organization.

Chirality or mirror asymmetry is a common theme in biology found in organismal body plans, tissue patterns and even in individual cells. In many cases the emergence of chirality is driven by actin cytoskeletal dynamics. Although it is well established that the actin cytoskeleton generates rotational forces at the molecular level, we are only beginning to understand how this can result in chiral behavior of the entire actin network in vivo. In this review, we will give an overview of actin driven chiralities across different length scales known until today. Moreover, we evaluate recent quantitative models demonstrating that chiral symmetry breaking of cells can be achieved by properly aligning molecular-scale torque generation processes in the actomyosin cytoskeleton.