Paracellular Water Channel

Abstract Whether tight junction permeates water is highly controversial. Across both epithelium and endothelium, significant water permeability remains when transcellular water channels - aquaporins are removed from the plasma membrane. Tricellular tight junction is a new concept. Regular bicellular tight junctions cannot seal the tricellular corners. In fact, tricellular tight junction is made of two classes of proteins - tricellulin and angulins, which are different from the components of bicellular tight junction. Unlike the bicellular tight junction that only permeates small molecules with diameter of