FIGURE 10:

Vinculin recruitment depends on a balance between integrin–ECM and cytoskeletal forces at different substrate stiffness values. (A) On stiff substrates, vinculin is recruited to better distribute high applied forces across FAs. High forces applied across vinculin stabilize vinculin at FAs to promote force transfer. Contractility inhibition unloads vinculin molecules and promotes disengagement from FAs. Paxillin recruitment is independent of stiffness and cytoskeletal (CSK) tension. (B) On soft substrates, less vinculin is recruited because there is less force to distribute across FAs. Consequently vinculin recruitment occurs through force-independent mechanisms. Contractility inhibition unloads vinculin molecules and promotes disengagement from FA, whereas paxillin recruitment is largely independent of stiffness and CSK tension.