Claudin 19 (CLDN19)

Claudins, such as CLDN19, are transmembrane proteins found at tight junctions.CLDN19 localized at apical and basolateral junctions between neighboring cells and in the luminal lining of renal tubules. Cytoplasm and nuclei also showed CLDN19 staining, and some nuclei were intensely stained. In polycystic kidneys, renal cyst epithelia showed decreased CLDN19 expression and variable CLDN19 localization, with diffuse staining throughout the cytoplasm and some staining of nuclei.Both deduced proteins contain 224 amino acids and have 4 transmembrane segments, and they share 95% amino acid identity. Cldn19 colocalized with Zo1 (TJP1) at junctional regions of canine kidney epithelial cells. Coimmunoprecipitation experiments showed that Zo1 and Cldn19 associated in protein complexes.