Claudin属于紧密连接蛋白家族,哺乳动物细胞的claudin有24个蛋白亚型,具有四个跨膜区,分别为细胞内的-NH2末端和-COOH末端,以及细胞外的初级大环和次级小环。Claudin广泛分布于肾脏的多种组织结构,如肾小管、血管、肾小体等。不同亚型在不同的肾单位节段表达,同一肾单位节段表达不同亚型。此外,claudin-16和-19基因突变与高尿钙和低血镁性肾钙质沉着病(FHHNC)的发生有密切联系,而多囊肾的发生可能与claudin-7基因突变有关。 Claudin belongs to the claudin family. Claudin in mammalian cells has 24 protein subtypes and has four transmembrane domains, namely the intracellular-NH2 and -COOH ends, as well as extracellular primary macrocycles and secondary small ring. Claudin widely distributed in the kidney a variety of organizational structures, such as tubules, blood vessels, kidney and so on. Different subtypes are expressed in different nephron segments and different subtypes are expressed in the same nephron segment. In addition, mutations in claudin-16 and -19 are closely associated with the development of hypercalciuria and hypocalmagnestic nephropathy (FHHNC), whereas polycystic kidney disease may be associated with mutations in the claudin-7 gene.