An Autoinhibited Structure of α-Catenin and Its Implications for Vinculin Recruitment to Adherens Junctions

• DOI: 10.1074/jbc.m113.453928
• Publication Date: 2013-04-16T00:13:21Z
• Authors: Noboru Ishiyama; Nobutoshi Tanaka; Kentaro Abe; Yoo Jeong Yang; Yazan M. Abbas; Masataka Umitsu; Bhushan Nagar; Stephanie A. Bueler; John L. Rubinstein; Masatoshi Takeichi; Mitsuhiko Ikura
• Keywords: Adherens junction; Vinculin

α-Catenin is an actin- and vinculin-binding protein that regulates cell-cell adhesion by interacting with cadherin receptors through β-catenin, but the mechanisms which it anchors cadherin-catenin complex to actin cytoskeleton at adherens junctions remain unclear. Here we determined crystal structures of αE-catenin in autoinhibited state actin-binding domain αN-catenin. Together small-angle x-ray scattering analysis full-length αN-catenin, deduced elongated multidomain assembly monomeric α-catenin structurally functionally couples vinculin- mechanisms. Cellular biochemical studies αE- αN-catenins show recruits vinculin more effectively than partly because its higher affinity for filaments. We propose a molecular switch mechanism involving multistate conformational changes α-catenin. This would be driven actomyosin-generated tension dynamically regulate vinculin-assisted linkage between cytoskeleton.