Model for regulation of non-muscle myosins

Diverse morphological changes of non-muscle eukaryotic cell are usually accompanied by dynamic remodeling in its cytoskeleton. The conformation/functional state of myosins is presumed to be markedly altered during cytoskeletal reorganization. Although myosins play critical roles in various forms of cellular movement and shape changes, the molecular basis for regulation of their activity is complicated and far from understood. A numerous experimental data show the phosphorylatable light chain (20 kDa), known as a regulatory light chain (RLC), as one of the key modulators of regulatory signals in the structure of myosin-II molecule. However, the clue that coordinates its phosphorylation state remains to be enigmatic. In the present work, we propose the most rationale mechanism which might regulate the state of RLC phosphorylation, and therefore, might control organization and activity of non-muscle myosins.