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Visualizing the interior architecture of focal adhesions with high-resolution traction maps.

ABSTRACT: Focal adhesions (FAs) are micron-sized protein assemblies that coordinate cell adhesion, migration, and mechanotransduction. How the many proteins within FAs are organized into force sensing and transmitting structures is poorly understood. We combined fluorescent molecular tension sensors with super-resolution light microscopy to visualize traction forces within FAs with <100 nm spatial resolution. We find that ?v?3 integrin selectively localizes to high force regions. Paxillin, which is not generally considered to play a direct role in force transmission, shows a higher degree of spatial correlation with force than vinculin, talin, or ?-actinin, proteins with hypothesized roles as force transducers. These observations suggest that ?v?3 integrin and paxillin may play important roles in mechanotransduction.

SUBMITTER: Morimatsu M

PROVIDER: S-EPMC5924765 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Visualizing the interior architecture of focal adhesions with high-resolution traction maps.

Morimatsu Masatoshi M Mekhdjian Armen H AH Chang Alice C AC Tan Steven J SJ Dunn Alexander R AR

Nano letters 20150323 4

Focal adhesions (FAs) are micron-sized protein assemblies that coordinate cell adhesion, migration, and mechanotransduction. How the many proteins within FAs are organized into force sensing and transmitting structures is poorly understood. We combined fluorescent molecular tension sensors with super-resolution light microscopy to visualize traction forces within FAs with <100 nm spatial resolution. We find that αvβ3 integrin selectively localizes to high force regions. Paxillin, which is not ge ...[more]

PMID: 25730141

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