Claudin 12 (CLDN12)

Claudins, such as CLDN12, are components of epithelial cell tight junctions. Tight junctions regulate movement of solutes and ions through the paracellular space and prevent mixing of proteins and lipids in the outer leaflet of the apical and basolateral plasma membrane domains.Using immunofluorescence microscopy, Acharya et al. (2004) showed that Cldn4, Cldn8, and Cldn12 localized to the bladder epithelium of rat, mouse, and rabbit. These claudins specifically localized to tight junctions of the superficial umbrella cell layer, consistent with the high-resistance, low-permeability barrier function of this cell type. Acharya et al. (2004) noted that mouse Cldn12 has also been localized to the blood-brain barrier, which is composed of high-resistance endothelial cells.