Ozono Kazutaka, Komiya Satoshi, Shimamura Kenji, Ito Takaaki, Nagafuchi Akira
Department of Cellular Interactions, Kumamoto University, Kumamoto, Japan.
Cell Struct Funct. 2011;36(1):131-43. doi: 10.1247/csf.11009.
To define the roles of α-catenin in cell-cell adhesion, the E-cadherin, α-catenin, β-catenin, and/or plakoglobin genes were inactivated in F9 teratocarcinoma cells. An E-cadherin-α-catenin fusion protein (Eα) restored full cell-adhesion function and organized the actin-based cytoskeleton and ZO-1, an actin filament binding protein, in F9 cells lacking all endogenous cadherin-catenin complex components. There were two types of cadherin-based cell-adhesion junctions in parental F9 cells, those with ZO-1 and those without ZO-1, and only junctions with ZO-1 were associated with thick actin bundles. Additionally, ZO-1 localized to most Eα-based cell-adhesion junctions. These data demonstrated that Eα supported cadherin-based cell adhesion and recruited actin bundles and ZO-1 to cell-cell contact sites in the absence of cytoplasmic α-catenin. Moreover, the C-terminal half of α-catenin was involved in the formation of cell-adhesion junctions with ZO-1.
为了确定α-连环蛋白在细胞间黏附中的作用，在F9畸胎瘤细胞中使E-钙黏蛋白、α-连环蛋白、β-连环蛋白和/或原钙黏蛋白基因失活。一种E-钙黏蛋白-α-连环蛋白融合蛋白（Eα）在缺乏所有内源性钙黏蛋白-连环蛋白复合体成分的F9细胞中恢复了完整的细胞黏附功能，并组织了基于肌动蛋白的细胞骨架和肌动蛋白丝结合蛋白ZO-1。亲代F9细胞中有两种基于钙黏蛋白的细胞黏附连接，即有ZO-1的连接和没有ZO-1的连接，只有有ZO-1的连接与粗大的肌动蛋白束相关。此外，ZO-1定位于大多数基于Eα的细胞黏附连接。这些数据表明，在没有细胞质α-连环蛋白的情况下，Eα支持基于钙黏蛋白的细胞黏附，并将肌动蛋白束和ZO-1招募到细胞间接触位点。此外，α-连环蛋白的C端一半参与了与ZO-1形成细胞黏附连接。
