Claudin 3+Claudin 9 重组兔单克隆抗体 (SDT-1452-69)-S0B2348

Claudin-3 and Claudin-9 are two closely related members of the Claudin family of tight junction proteins, both belonging to the classical Claudin subclass that primarily serves barrier functions. Their most notable shared features lie in their highly similar protein sequences and common receptor properties: Claudin-3 and Claudin-9 share a consistent overall fold and both can bind Clostridium perfringens enterotoxin (CPE). In terms of expression and distribution, they display patterns that are both overlapping and distinct: Claudin-3 is highly expressed in choroid plexus epithelium, where it constitutes an important component of the blood-cerebrospinal fluid barrier, and is also commonly found in various epithelia such as the ovary and mammary gland; Claudin-9, on the other hand, has been identified in the inner ear, cornea, liver, and developing kidney, and serves as one of the auxiliary receptors for hepatitis C virus. Regarding physiological function, both contribute to enhancing epithelial barrier tightness, but their specific roles differ: Claudin-3 expression declines during development, whereas Claudin-9 expression increases with development, suggesting that they undertake distinct tasks during barrier maturation. Furthermore, Claudin-3 is dysregulated in multiple cancers and is often regarded as a potential therapeutic target, while Claudin-9 has also been proposed to possibly participate in the formation of tricellular junction barriers.