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Stretching single talin rod molecules activates vinculin binding.

ABSTRACT: The molecular mechanism by which a mechanical stimulus is translated into a chemical response in biological systems is still unclear. We show that mechanical stretching of single cytoplasmic proteins can activate binding of other molecules. We used magnetic tweezers, total internal reflection fluorescence, and atomic force microscopy to investigate the effect of force on the interaction between talin, a protein that links liganded membrane integrins to the cytoskeleton, and vinculin, a focal adhesion protein that is activated by talin binding, leading to reorganization of the cytoskeleton. Application of physiologically relevant forces caused stretching of single talin rods that exposed cryptic binding sites for vinculin. Thus in the talin-vinculin system, molecular mechanotransduction can occur by protein binding after exposure of buried binding sites in the talin-vinculin system. Such protein stretching may be a more general mechanism for force transduction.

SUBMITTER: del Rio A

PROVIDER: S-EPMC9339221 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature

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Stretching single talin rod molecules activates vinculin binding.

del Rio Armando A Perez-Jimenez Raul R Liu Ruchuan R Roca-Cusachs Pere P Fernandez Julio M JM Sheetz Michael P MP

Science (New York, N.Y.) 20090101 5914

The molecular mechanism by which a mechanical stimulus is translated into a chemical response in biological systems is still unclear. We show that mechanical stretching of single cytoplasmic proteins can activate binding of other molecules. We used magnetic tweezers, total internal reflection fluorescence, and atomic force microscopy to investigate the effect of force on the interaction between talin, a protein that links liganded membrane integrins to the cytoskeleton, and vinculin, a focal adh ...[more]

PMID: 19179532

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Activation of a vinculin-binding site in the talin rod involves rearrangement of a five-helix bundle.

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