Download MendeleyThe Architecture of Talin1 Reveals an Autoinhibition Mechanism.
Dedden, D., Schumacher, S., Kelley, C.F., Zacharias, M., Biertumpfel, C., Fassler, R., Mizuno, N.(2019) Cell 179: 120-131.e13
- PubMed: 31539492
- DOI: https://doi.org/10.1016/j.cell.2019.08.034
- Primary Citation of Related Structures:
6R9T - PubMed Abstract:
Focal adhesions (FAs) are protein machineries essential for cell adhesion, migration, and differentiation. Talin is an integrin-activating and tension-sensing FA component directly connecting integrins in the plasma membrane with the actomyosin cytoskeleton. To understand how talin function is regulated, we determined a cryoelectron microscopy (cryo-EM) structure of full-length talin1 revealing a two-way mode of autoinhibition. The actin-binding rod domains fold into a 15-nm globular arrangement that is interlocked by the integrin-binding FERM head. In turn, the rod domains R9 and R12 shield access of the FERM domain to integrin and the phospholipid PIP 2 at the membrane. This mechanism likely ensures synchronous inhibition of integrin, membrane, and cytoskeleton binding. We also demonstrate that compacted talin1 reversibly unfolds to an ∼60-nm string-like conformation, revealing interaction sites for vinculin and actin. Our data explain how fast switching between active and inactive conformations of talin could regulate FA turnover, a process critical for cell adhesion and signaling.
Organizational Affiliation:
Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
