Abstract
Adherens junction (AJ), which links actin cytoskeletons in adjacent cells, directly senses and balances intercellular tension that drives dynamical processes such as morphogenesis and wound healing. As a mechano-sensitive molecule at AJ, α-catenin recruits vinculin under intercellular tension resulting in local actin remodeling. However, little is known about mechanical behaviors of α-catenin after vinculin recruitment. In general, adhesive molecules such as a-catenin tend to unfold under low tension. Here, we revealed how a-catenin steadily transmit intercellular tension while keeping the interaction with vinculin, by employing single-molecule interaction measurement using atomic force microscopy (AFM). In our experiments, AFM probe modified with vinculin was contacted to α-catenin-modified substrate resulting in the formation of α-catenin-vinculin complex that which was finally loaded. As a result, we found that α-catenin changes its conformation under intercellular tension in order to conserve the interaction with vinculin. Furthermore, we suggested that an intramolecular interaction in a-catenin influences the unbinding force between a-catenin and vinculin.
