The Company of Biologists, Journal of Cell Science, 2019
DOI: 10.1242/jcs.226514
Full text: Unavailable
Talin is one of the key components in integrin-mediated adhesion complexes. Talin transmits mechanical forces between β-integrin and actin and regulates adhesion complex composition and signaling through the force-regulated unfolding of talin rod domain. Using modified talin proteins, we demonstrate that these functions contribute to different cellular processes and can be dissected. The transmission of mechanical forces regulates adhesion complex composition and phosphotyrosine signaling even in the absence of the mechanically-regulated talin rod subdomains. However, the presence of the rod subdomains and their mechanical activation are required for the reinforcement of the adhesion complex, cell polarization and migration. Talin rod domain unfolding was also found to be essential for the generation of cellular signaling anisotropy, since both insufficient and excess activity of the rod domain severely inhibited cell polarization. Utilizing proteomics tools we identified adhesome components that are recruited and activated either in a talin rod-dependent manner or independently of the rod subdomains. This study clarifies the division of roles between the force-regulated unfolding of talin and the function of talin as a physical linker between integrins and the cytoskeleton.