Mechanosensitive adhesion complexes and complex cell motility patterns

Hsuan-Yi Chen^1,2*, Jen-Yu Lo¹

¹Department of Physics, National Central University, Taoyuan, Taiwan
²Institute of Physics, Academia Sinica, Taipei, Taiwan

* Presenter:Hsuan-Yi Chen, email:hschen@phy.ncu.edu.tw

A biological cell adhered to a substrate by adhesion complexes exhibits crawling motion powered by actin polymerization and actomyosin contractility. It has been observed experimentally that the cell crawling behaviors are affected by the mechanosensitive adhesion complexes between the cell and the substrate. However, not sufficient details are known for theoretical models to explain the relation between the properties of the adhesion complexes and cell crawling behavior at the quantitative level.

The key questions include: (i) what type of mechanosensitivity is needed to induce the change of cell crawling pattern, (ii) what are the roles played by actin polymerization and contractility of actomyosin cytoskeleton affects, and (iii) whether biochemical signaling are essential for crawling cells to exhibit such complex behaviors.

I will discuss these issues with a minimal theoretical model that incorporates mechanosensitive adhesion complexes with an active gel that mimics cell cytoplasm. The key results are (i) the crawling behaviors are sensitive to the change of the response of the adhesion complexes to either stretching/compressing,or a net external force, depending on the spatial distribution of the adhesion complexes, (ii) actin polymerization works against the change of cell polarity, while feedbacks between myosin contractility and mechanosensitive adhesion complexes generates complex motility behaviors, and (iii) the biochemical signaling can determine what type of mechanosensitivity is more important by tunning the spatial distribution of the mechanosensitive adhesion complexes in a cell.

Keywords: mechanobiophysics, active matters, nonlinear dynamics, cell motility