A feedback circuitry involving γ-actin, β-actin and nonmuscle myosin-2 A controls tight junction and apical cortex mechanics.

ABSTRACT: Cytoplasmic β- and γ-actin isoforms, along with non-muscle myosin 2 isoforms, are tightly regulated in epithelial cells and compose the actomyosin cytoskeleton at the apical junctional complex. However, their specific role in regulating the mechanics of the membrane cortex and the organization of junctions, and which biomechanical circuitries modulate their expression remain poorly understood. Here, we show that γ-actin depletion in MDCK and other epithelial cells results in increased expression and junctional accumulation of β-actin and increased tight junction membrane tortuosity, both dependent on nonmuscle myosin-2A upregulation. The knock-out of γ-actin also decreases apical membrane stiffness and increases dynamic exchange of the cytoplasmic tight junction proteins like ZO-1 and cing

SUBMITTER: Mauperin M 

PROVIDER: S-EPMC11906862 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature