CLDN2
Function
Forms paracellular channels: polymerizes in tight junction strands with cation- and water-selective channels through the strands, conveying epithelial permeability in a process known as paracellular tight junction permeability (PubMed:20460438, PubMed:36008380). In intestinal epithelium, allows for sodium and water fluxes from the peritoneal side to the lumen of the intestine to regulate nutrient absorption and clear enteric pathogens as part of mucosal immune response (By similarity). In kidney, allows passive sodium and calcium reabsorption across proximal tubules from the lumen back to the bloodstream (By similarity). In the hepatobiliary tract, allows paracellular water and cation fluxes in the hepatic perivenous areas and biliary epithelium to generate bile flow and maintain osmotic gradients (By similarity).
Involvement in disease
Azoospermia, obstructive, with nephrolithiasis
OAZON
An X-linked recessive, male infertility disorder characterized by epidydimal obstruction, hypercalciuria and kidney stones.
None
The disease may be caused by variants affecting the gene represented in this entry.
Post-translational modifications
The disulfide bond is necessary for pore formation, but is not required for correct protein trafficking.
Sequence Similarities
Belongs to the claudin family.
Cellular localization
- Cell junction
- Tight junction
- Cell membrane
- Multi-pass membrane protein
Alternative names
PSEC0059, SP82, UNQ705/PRO1356, CLDN2, Claudin-2