Troy Tammy-Claire, Arabzadeh Azadeh, Yerlikaya Seda, Turksen Kursad
Ottawa Health Research Institute, 725 Parkdale Avenue, Ottawa, ON, K1Y 4E9, Canada.
Cell Tissue Res. 2007 Nov;330(2):381-8. doi: 10.1007/s00441-007-0487-2. Epub 2007 Sep 9.
Emerging evidence supports the notion that claudins (Cldns) are dynamically regulated under normal conditions to respond to the selective permeability requirements of various tissues, and that their expression is developmentally controlled. We describe the localization of those Cldns that we have previously demonstrated to be functionally important in epidermal differentiation and the formation of the epidermal permeability barrier, e.g., Cldn1, Cldn6, Cldn11, and Cldn18, and the presence of Cldn3 and Cldn5 in various neonatal mouse epithelia including the epidermis, nail, oral mucosa, tongue, and stomach. Cldn1 is localized in the differentiated and/or undifferentiated compartments of the epidermis and nail and in the dorsal surface of the tongue and glandular compartment of the stomach but is absent from the oral mucosa and the keratinized compartment of the stomach. Cldn3 is present in the basal cells of the nail matrix and both compartments of the murine stomach but not in the epidermis, oral mucosa, or tongue. Cldn5 is found in the glandular compartment of the stomach but not in the epidermis, nail unit, oral mucosa, forestomach, and tongue. Cldn6, Cldn11, and Cldn18 occur in the differentiating suprabasal compartment of the epidermis, nail, and oral mucosa and in the dorsal and ventral surfaces of the tongue and the keratinized squamous epithelium of the stomach. The simple columnar epithelium of the glandular stomach stains for Cldn18 and reveals a non-membranous pattern for Cldn6 and Cldn11 expression. Our results demonstrate differential Cldn protein profiles in various epithelial tissues and their differentiation stages. Although the molecular mechanisms regulating Cldn expression are unknown, elucidation of their differential localization patterns in tissues with diverse permeability requirements should provide a better understanding of the role of tight junctions in tissue function.
新出现的证据支持这样一种观点，即紧密连接蛋白（Cldns）在正常条件下受到动态调节，以响应各种组织对选择性通透性的需求，并且其表达受发育调控。我们描述了那些我们之前已证明在表皮分化和表皮通透性屏障形成中具有重要功能的紧密连接蛋白的定位，例如Cldn1、Cldn6、Cldn11和Cldn18，以及Cldn3和Cldn5在包括表皮、指甲、口腔黏膜、舌头和胃在内的各种新生小鼠上皮组织中的存在情况。Cldn1定位于表皮和指甲的分化和/或未分化区室、舌头的背面以及胃的腺区室，但在口腔黏膜和胃的角化区室中不存在。Cldn3存在于指甲基质的基底细胞以及小鼠胃的两个区室中，但在表皮、口腔黏膜或舌头中不存在。Cldn5存在于胃的腺区室中，但在表皮、甲单位、口腔黏膜、前胃和舌头中不存在。Cldn6、Cldn11和Cldn18出现在表皮、指甲和口腔黏膜的分化上层区室以及舌头的背面和腹面以及胃的角化鳞状上皮中。腺胃的单层柱状上皮细胞对Cldn18染色，并显示出Cldn6和Cldn11表达的非膜性模式。我们的结果表明，不同上皮组织及其分化阶段存在不同的紧密连接蛋白表达谱。尽管调节紧密连接蛋白表达的分子机制尚不清楚，但阐明它们在具有不同通透性需求的组织中的差异定位模式，应该能更好地理解紧密连接在组织功能中的作用。
