α-catenin phosphorylation is actomyosin-sensitive and required for epithelial barrier functions through Afadin.

ABSTRACT: Zonula adherens junctions (zAJ) are spatially proximal to tight junctions (TJ), in a superstructure known as the apical junctional complex (AJC). A key component of the AJC is a circumferential ring of filamentous (F)-actin, but how actomyosin contractility drives AJC structure and epithelial barrier function is incompletely understood. Here, we show that a central mechanosensitive component of zAJ, α-catenin (α-cat), undergoes force-dependent phosphorylation in an unstructured linker region. This modification in turn primes the α-cat mechanosensitive Middle-region for effector-binding. We credential Afadin, a multi-domain TJ/AJ scaffold protein, as mechano-chemical binding partner of α-cat, identifying residues in α-cat required for this interaction. α-cat phosphorylation and Afadin-bindi

SUBMITTER: Quinn JM 

PROVIDER: S-EPMC12393524 | biostudies-literature | 2025 Aug

REPOSITORIES: biostudies-literature