CLDN2
CLDN2 (claudin 2) is a member of the claudin family of integral membrane proteins found at tight junctions. It forms cation- and water-selective paracellular channels that determine epithelial permeability in tissues such as the intestine, kidney and hepatobiliary tract. Browse Assay Genie's current range of CLDN2 research reagents below, or read on for the biology behind the target.
CLDN2 polymerises in tight junction strands, where it forms paracellular channels that are selective for cations and water. Through these channels it contributes to epithelial permeability, a process known as paracellular tight junction permeability. The channels allow passive movement of ions and water between neighbouring cells rather than through them.
The role of claudin-2 differs by tissue. In intestinal epithelium it allows sodium and water fluxes from the peritoneal side to the lumen, which helps regulate nutrient absorption and clear enteric pathogens as part of the mucosal immune response. In the kidney it allows passive sodium and calcium reabsorption across proximal tubules, from the lumen back to the bloodstream. In the hepatobiliary tract it supports paracellular water and cation fluxes in hepatic perivenous areas and biliary epithelium, generating bile flow and maintaining osmotic gradients.
The CLDN2 gene belongs to the claudins gene group, and its product is one of the major integral membrane proteins localised exclusively at tight junctions. Claudins are expressed in an organ-specific manner and regulate the tissue-specific physiological properties of tight junctions. Claudin-2 is expressed in the intestine, and alternatively spliced transcript variants with different 5' untranslated regions have been reported for the gene. The mouse ortholog is Cldn2.
CLDN2 forms cation- and water-selective channels within tight junction strands, making it a core subject for studying paracellular permeability.
Claudin-2 allows sodium and water fluxes into the intestinal lumen, supporting nutrient absorption and the clearance of enteric pathogens.
In proximal tubules, claudin-2 allows passive sodium and calcium reabsorption from the lumen back to the bloodstream.
CLDN2 supports paracellular water and cation fluxes in perivenous areas and biliary epithelium, generating bile flow and osmotic gradients.
CLDN2 polymerises in tight junction strands to form paracellular channels selective for cations and water. These channels convey epithelial permeability, allowing sodium, calcium and water to pass between cells in the intestine, kidney proximal tubules and the hepatobiliary tract.
They refer to the same target. CLDN2 is the HGNC gene symbol for claudin 2, and Claudin-2 is the UniProt protein name. No alternative aliases or previous symbols are listed. The protein belongs to the claudin family and the claudins gene group.
A mouse ortholog, Cldn2, is recorded for this gene. Within the claudin family, expression is organ-specific, and NCBI notes that claudin-2 is expressed in the intestine. Check the datasheet of any product for its validated reactivity.
Other claudin family members and tight junction proteins with products at Assay Genie.
Gene and protein annotations from HGNC, NCBI Gene and UniProt P57739; product specifications from Assay Genie datasheets.