Characterization of ZO-2 as a MAGUK family member associated with tight as well as adherens junctions with a binding affinity to occludin and α catenin

作     者：Itoh, M Morita, K Tsukita, S 

作者机构：Kyoto Univ Fac Med Dept Cell Biol Sakyo Ku Kyoto 606 Japan Kyoto Univ Fac Med Dept Dermatol Sakyo Ku Kyoto 606 Japan 

出 版 物：《JOURNAL OF BIOLOGICAL CHEMISTRY》 (生物化学杂志)

年 卷 期：1999年第274卷第9期

页      面：5981-5986页

核心收录：

学科分类：0710[理学-生物学] 071010[理学-生物化学与分子生物学] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 

主　　题：抗体/免疫学 细胞 培养的 克隆 分子 细胞支架蛋白质类/代谢 DNA 互补 膜蛋白质类/遗传学 膜蛋白质类/免疫学 膜蛋白质类/代谢 磷蛋白类/代谢 蛋白质结合 亚细胞部分/代谢 紧密连接部/代谢 α连环素 动物 小鼠 

摘      要：ZO-2, a member of the MAGUK family, was thought to be specific for tight junctions (TJs) in contrast to ZO-1, another MAGUK family member, which is localized at TJs and adherens junctions (AJs) in epithelial and nonepithelial cells, respectively. Mouse ZO-2 cDNA was isolated, and a specific polyclonal antibody was generated using corresponding synthetic peptides as antigens. Immunofluorescence microscopy with this polyclonal antibody revealed that, similarly to ZO-1, in addition to TJs in epithelial cells, ZO-2 was also concentrated at AJs in nonepithelial cells such as fibroblasts and cardiac muscle cells lacking TJs. When NH2-terminal dig-like and COOH-terminal non-dig-like domains of ZO-2 (N-ZO-2 and C-ZO-2, respectively) were separately introduced into cultured cells, N-ZO-2 was colocalized with endogenous ZO-1/ZO-2, i.e. at TJs in epithelial cells and at AJs in non-epithelial cells, whereas C-ZO-2 was distributed along actin filaments. Consistently, occludin as well as a: catenin directly bound to N-ZO-2 as well as the NH2-terminal dig-like portion of ZO-1 (N-ZO-1) in vitro. Furthermore, immunoprecipitation experiments revealed that the second PDZ domain of ZO-2 was directly associated with N-ZO-1. These findings indicated that ZO-2 forms a complex with ZO-1/occludin or ZO-1/alpha catenin to establish TJ or AJ domains, respectively.