Claudins are tight junction proteins mostly appreciated in their function of paracellular barrier-formation. Compared to a virtual absence of any tight junctions, their paracellular sealing role certainly stands out. Yet, it was recognized immediately after the discovery of the first claudins, that some members of the claudin protein family were able to convey size and charge selectivity to the paracellular pathway. Thus, paracellular permeability can be fine-tuned according to the physiological needs of a tissue by inserting these channel-forming claudins into tight junction strands. Precise permeability adjustment is further suggested by the presence of numerous isoforms of channel-forming claudins (claudin-10b-, -15-, -16-like isoforms) in various vertebrate taxa. Moreover, their expression and localization are controlled by multiple transcriptional and posttranslational mechanisms. Consequently, mutation or dysregulation of channel-forming claudins can cause severe diseases. The present review therefore aims at providing an up-to-date report of the current research on these aspects of channel-forming claudins and their possible implications on future developments.

中文翻译：

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claudins在生物系统组织中的通道功能。

claudins是紧密连接蛋白，最受其副细胞屏障形成功能的赞赏。与实际上没有任何紧密连接的相比，它们的细胞旁密封作用无疑是突出的。然而，在发现第一个claudins后立即认识到claudin蛋白家族的某些成员能够将大小和电荷选择性传递至旁细胞途径。因此，通过将这些形成通道的claudins插入紧密的连接链中，可以根据组织的生理需要对细胞旁的通透性进行微调。各种脊椎动物类群中通道形成型claudins的许多同工型（claudin-10b，-15，-16样同工型）的存在进一步暗示了精确的渗透性调节。此外，它们的表达和定位受多种转录和翻译后机制控制。因此，通道形成claudins的突变或失调可导致严重疾病。因此，本综述旨在提供有关通道形成claudins的这些方面及其对未来发展可能的影响的最新研究的最新报告。