RT Journal Article SR Electronic T1 Vinculin is critical for the robustness of the epithelial cell sheet paracellular barrier for ions JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e201900414 DO 10.26508/lsa.201900414 VO 2 IS 4 A1 Satoshi Konishi A1 Tomoki Yano A1 Hiroo Tanaka A1 Tomoaki Mizuno A1 Hatsuho Kanoh A1 Kazuto Tsukita A1 Toshinori Namba A1 Atsushi Tamura A1 Shigenobu Yonemura A1 Shimpei Gotoh A1 Hisako Matsumoto A1 Toyohiro Hirai A1 Sachiko Tsukita YR 2019 UL https://www.life-science-alliance.org/content/2/4/e201900414.abstract AB The paracellular barrier function of tight junctions (TJs) in epithelial cell sheets is robustly maintained against mechanical fluctuations, by molecular mechanisms that are poorly understood. Vinculin is an adaptor of a mechanosensory complex at the adherens junction. Here, we generated vinculin KO Eph4 epithelial cells and analyzed their confluent cell-sheet properties. We found that vinculin is dispensable for the basic TJ structural integrity and the paracellular barrier function for larger solutes. However, vinculin is indispensable for the paracellular barrier function for ions. In addition, TJs stochastically showed dynamically distorted patterns in vinculin KO cell sheets. These KO phenotypes were rescued by transfecting full-length vinculin and by relaxing the actomyosin tension with blebbistatin, a myosin II ATPase activity inhibitor. Our findings indicate that vinculin resists mechanical fluctuations to maintain the TJ paracellular barrier function for ions in epithelial cell sheets.