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Cell adhesion. The minimal cadherin-catenin complex binds to actin filaments under force.

ABSTRACT: Linkage between the adherens junction (AJ) and the actin cytoskeleton is required for tissue development and homeostasis. In vivo findings indicated that the AJ proteins E-cadherin, ?-catenin, and the filamentous (F)-actin binding protein ?E-catenin form a minimal cadherin-catenin complex that binds directly to F-actin. Biochemical studies challenged this model because the purified cadherin-catenin complex does not bind F-actin in solution. Here, we reconciled this difference. Using an optical trap-based assay, we showed that the minimal cadherin-catenin complex formed stable bonds with an actin filament under force. Bond dissociation kinetics can be explained by a catch-bond model in which force shifts the bond from a weakly to a strongly bound state. These results may explain how the cadherin-catenin complex transduces mechanical forces at cell-cell junctions.

SUBMITTER: Buckley CD

PROVIDER: S-EPMC4364042 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Cell adhesion. The minimal cadherin-catenin complex binds to actin filaments under force.

Buckley Craig D CD Tan Jiongyi J Anderson Karen L KL Hanein Dorit D Volkmann Niels N Weis William I WI Nelson W James WJ Dunn Alexander R AR

Science (New York, N.Y.) 20141001 6209

Linkage between the adherens junction (AJ) and the actin cytoskeleton is required for tissue development and homeostasis. In vivo findings indicated that the AJ proteins E-cadherin, β-catenin, and the filamentous (F)-actin binding protein αE-catenin form a minimal cadherin-catenin complex that binds directly to F-actin. Biochemical studies challenged this model because the purified cadherin-catenin complex does not bind F-actin in solution. Here, we reconciled this difference. Using an optical t ...[more]

PMID: 25359979

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