TJP1 and intestinal disorder: Their intracellular parts interact with cytoplasmic peripheral membrane proteins such as zonular occludens (ZO-1, −2, and −3) and cingulin.65,68 These proteins interact with F-actin and myosin II in epithelial cells to control contraction and barrier loss of tight junction.69 In particular, this barrier loss has been suggested to be responsible for various intestinal diseases.