Health Dictionary Find a Doctor

CLDN2

Claudin-2 is a protein that in humans is encoded by the CLDN2 gene.[1][2] It belongs to the group of claudins.

Members of the claudin protein family, such as CLDN2, are expressed in an organ-specific manner and regulate the tissue-specific physiologic properties of tight junctions (Sakaguchi et al., 2002).[supplied by OMIM][2]

Function

Claudin-2 is expressed in cation-leaky epithelia such as that of the kidney proximal tubule.[3] Mice that are deficient in claudin-2 have reduced reabsorption of Na+ in the proximal tubule, consistent with a role in paracellular transport. Similar results have been obtained with cultured cells, as overexpression in claudin-2 lacking cells leads to increase of permeability for small cations.[4] Furthermore, claudin-2 has been shown to form paracellular channels for water.[5]

References

  1. Morita K, Furuse M, Fujimoto K, Tsukita S (March 1999). “Claudin multigene family encoding four-transmembrane domain protein components of tight junction strands”. Proc Natl Acad Sci U S A. 96 (2): 511–6. doi:10.1073/pnas.96.2.511. PMC 15167. PMID 9892664.
  2. 2.0 2.1 “Entrez Gene: CLDN2 claudin 2”.
  3. Muto, S.; Hata, M.; Taniguchi, J.; Tsuruoka, S.; Moriwaki, K.; Saitou, M.; Furuse, K.; Sasaki, H.; Fujimura, A.; Imai, M.; Kusano, E.; Tsukita, S.; Furuse, M. (2010). “Claudin-2-deficient mice are defective in the leaky and cation-selective paracellular permeability properties of renal proximal tubules”. Proceedings of the National Academy of Sciences. 107 (17): 8011–8016. doi:10.1073/pnas.0912901107. PMC 2867900. PMID 20385797.
  4. Amasheh, S; Meiri, N; Gitter, A. H.; Schöneberg, T; Mankertz, J; Schulzke, J. D.; Fromm, M (2002). “Claudin-2 expression induces cation-selective channels in tight junctions of epithelial cells”. Journal of Cell Science. 115 (Pt 24): 4969–76. doi:10.1242/jcs.00165. PMID 12432083.
  5. Rosenthal, R.; Milatz, S.; Krug, S. M.; Oelrich, B.; Schulzke, J. -D.; Amasheh, S.; Gunzel, D.; Fromm, M. (2010). “Claudin-2, a component of the tight junction, forms a paracellular water channel”. Journal of Cell Science. 123 (11): 1913–1921. doi:10.1242/jcs.060665. PMID 20460438.

Further reading



© 2026 MyEClinic – IFTM Institut für Telematik in der Medizin GmbH