Mechanical Stress-Induced Autophagy is Cytoskeleton Dependent.

The cytoskeleton is essential for mechanical signal transduction and autophagy. However, few studies have directly demonstrated the contribution of the cytoskeleton to mechanical stress-induced autophagy. We explored the role of the cytoskeleton in response to compressive force-induced autophagy in human cell lines. Inhibition and activation of cytoskeletal polymerization using small chemical molecules revealed that cytoskeletal microfilaments are required for changes in the number of autophagosomes, whereas microtubules play an auxiliary role in mechanical stress-induced autophagy. The intrinsic mechanical properties and special intracellular distribution of microfilaments may account for a large proportion of compression-induced autophagy. Our experimental data support that microfilaments are core components of mechanotransduction signals. Microfilaments are an essential element, whereas microtubules play a relatively small role as an auxiliary factor in mechanical stress-induced autophagy. The deformation of the elastic cortical microfilaments caused by compression accounts for a large proportion of force-induced autophagy. image