Alix-mediated assembly of the actomyosin–tight junction polarity complex preserves epithelial polarity and epithelial barrier

Correct assembly of intercellular junctions is required to maintain epithelial polarity and barrier function. Here Campos et al. show that the scaffold protein Alix interacts with F-actin, the Par complex and ZO-1 to ensure the formation and maintenance of the actomyosin tight junction complex in choroid plexus epithelium.