Microtubules tune mechanosensitive cell responses

Abstract : Mechanotransduction is a process by which cells sense the mechanical properties of their surrounding environment and adapt accordingly to perform cellular functions such as adhesion, migration and differentiation. Integrin-mediated focal adhesions are major sites of mechanotransduction and their connection with the actomyosin network is crucial for mechanosensing as well as the generation and transmission of forces onto the substrate. Despite having emerged as major regulators of cell adhesion and migration, the contribution of microtubules to mechanotransduction still remains elusive. Here, we show that actomyosin-dependent mechanosensing of substrate rigidity controls microtubule acetylation, a tubulin post-translational modification, by promoting the recruitment of the alpha-tubulin acetyl transferase (αTAT1) to focal adhesions. Microtubule acetylation, in turn, promotes GEF-H1 mediated RhoA activation, actomyosin contractility and traction forces. Our results reveal a fundamental crosstalk between microtubules and actin in mechanotransduction, which contributes to mechanosensitive cell adhesion and migration.