Claudins form the paracellular tight junction seal in epithelial tissues. In humans, 24 claudins (claudin 1-24) have been identified. Their ability to polymerise and form strands is affected by the cell types [[cite:PUB00070981], [cite:PUB00070980], [cite:PUB00070979]]. They can also form heteropolymers with each other within and between tight junction strands [[cite:PUB00070982]]. Most of the claudins (claudin-12 being the exception) have a C-terminal PDZ-binding motif that can interact with other PDZ domain proteins, such as scaffolding protein, ZO-1, -2 and -3 [[cite:PUB00070979]]. They also interact with non-tight junction proteins, such as cell adhesion proteins EpCam and tetraspanins and the signaling proteins, ephrin A and B and their receptors, EphA and EphB [[cite:PUB00070979]].
","llm":false,"checked":false,"updated":false},{"text":"Claudin-6 was identified through searching expressed sequence tag (EST)\r\ndatabases for sequences similar to claudin-1 and -2 [[cite:PUB00004927]]. It was subsequently cloned and expressed in cells, where it was shown to concentrate at tight junctions. Human and mouse isoforms have been identified. Claudin-6 shares ~25-70% overall similarity with other claudin family members at the amino acid level, displaying highest similarity to claudin-9.
","llm":false,"checked":false,"updated":false}],"wikipedia":null,"literature":{"PUB00070982":{"PMID":10562289,"ISBN":null,"volume":"147","issue":"4","year":1999,"title":"Manner of interaction of heterogeneous claudin species within and between tight junction strands.","URL":null,"raw_pages":"891-903","medline_journal":"J Cell Biol","ISO_journal":"J. Cell Biol.","authors":["Furuse M","Sasaki H","Tsukita S."],"DOI_URL":"http://dx.doi.org/10.1083/jcb.147.4.891"},"PUB00070980":{"PMID":20188437,"ISBN":null,"volume":"89","issue":"7","year":2010,"title":"The protoplasmic or exoplasmic face association of tight junction particles cannot predict paracellular permeability or heterotypic claudin compatibility.","URL":null,"raw_pages":"547-56","medline_journal":"Eur J Cell Biol","ISO_journal":"Eur. J. Cell Biol.","authors":["Inai T","Kamimura T","Hirose E","Iida H","Shibata Y."],"DOI_URL":"http://dx.doi.org/10.1016/j.ejcb.2010.01.003"},"PUB00070981":{"PMID":21372174,"ISBN":null,"volume":"22","issue":"9","year":2011,"title":"Role of claudin species-specific dynamics in reconstitution and remodeling of the zonula occludens.","URL":null,"raw_pages":"1495-504","medline_journal":"Mol Biol Cell","ISO_journal":"Mol. Biol. Cell","authors":["Yamazaki Y","Tokumasu R","Kimura H","Tsukita S."],"DOI_URL":"http://dx.doi.org/10.1091/mbc.E10-12-1003"},"PUB00004927":{"PMID":9892664,"ISBN":null,"volume":"96","issue":"2","year":1999,"title":"Claudin multigene family encoding four-transmembrane domain protein components of tight junction strands.","URL":null,"raw_pages":"511-6","medline_journal":"Proc Natl Acad Sci U S A","ISO_journal":"Proc. Natl. Acad. Sci. U.S.A.","authors":["Morita K","Furuse M","Fujimoto K","Tsukita S."],"DOI_URL":"http://dx.doi.org/10.1073/pnas.96.2.511"},"PUB00070979":{"PMID":24665401,"ISBN":null,"volume":"1","issue":"3","year":2013,"title":"Claudin interactions in and out of the tight junction.","URL":null,"raw_pages":"e25247","medline_journal":"Tissue Barriers","ISO_journal":"Tissue Barriers","authors":["Van Itallie CM","Anderson JM."],"DOI_URL":"http://dx.doi.org/10.4161/tisb.25247"}},"set_info":null,"overlaps_with":null,"counters":{"subfamilies":0,"domain_architectures":0,"interactions":0,"matches":490,"pathways":1,"proteins":155,"proteomes":119,"sets":0,"structural_models":{"alphafold":132,"bfvd":0},"structures":0,"taxa":400},"entry_annotations":{},"cross_references":{},"is_llm":false,"is_reviewed_llm":false,"is_updated_llm":false,"representative_structure":null}}