ROCK and Dia have opposing effects on adherens junctions downstream of Rho.

Adherens junctions (AJs) are crucial for maintaining the integrity of epithelial tissues and are often disrupted during tumour progression. Rho family proteins have been shown to regulate adherens junctions. We find that activation of the effector kinase ROCK and acto-myosin contraction disrupts AJs downstream of Rho. In contrast, signalling through the Rho effector Dia1 is required to ensure a dynamically stable interface between cells and the maintenance of adherens junction complexes. The ability of Dia1 to regulate the actin network is crucial for the localization of adherens junction components to the cell periphery.