Dynamics of Cellular Reorientation on a Substrate under Biaxial Cyclic Stretches

It is widely known that mechanical signals such as force, geometry, and substrate elasticity can be utilized by cells to regulate their structures, functions, and behaviors. However, the exact nature of the underlying mechanisms of cellular mechanosensing is unclear. Recently, extensive experiments on cellular reorientation dynamics on a substrate under biaxial cyclic stretches were performed, and the measured behaviors were found to be incompatible with existing theories. Here, we show that a theoretical model based on both tensile and shearing forces on focal adhesions (FAs) is capable of reproducing the new experimental data. This work provides important mechanistic insights into how behaviors of FAs can strongly affect cellular reorientation dynamics on a cyclically stretched substrate.