Biochemomechanical Tensegrity Model of Cytoskeletons

Abstract

Active deformation and remodeling of cytoskeletons play a key role in many physiological and pathological dynamic processes such as embryonic development, regulation of the epigenetic state, and cancer invasion. However, it remains unclear how such molecular mechanisms as the polymerization and depolymerization of actin and microtubular networks, the motion of motors, and the regulation of upstream molecular signals coordinate the dynamic behaviors of cells. In this paper, we establish a biochemomechanical tensegrity model of cytoskeletons to investigate the spatiotemporal dynamics of cells. The reaction and diffusion of biochemical factors, the active contraction of actomyosin filaments, and mechanical–chemical feedback mechanisms are considered in this model. Instability analysis is performed to capture the dominant features of the active behaviors of cytoskeletons and scrutinize the role of mechanical–chemical feedback in the dynamic state transitions. Then, this model is applied to analyze the complicated processes spanning from the dynamic behaviors of an actomyosin string to the periodic cellular oscillations, which are pivotal for embryonic development and cancer invasion. It is revealed that the interplay of internal active forces and chemical reactions may induce spontaneous oscillations of cells. The results agree well with relevant experimental measurements. This work provides not only a theoretical framework for studying the multiscale biochemomechanical coupling behaviors of cytoskeletons but also a tool for simulating the spatiotemporal dynamics of cells under various physiological and pathological conditions.