Lu Q, Paredes M, Medina M, Zhou J, Cavallo R, Peifer M, Orecchio L, Kosik K S
Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
J Cell Biol. 1999 Feb 8;144(3):519-32. doi: 10.1083/jcb.144.3.519.
The classical adherens junction that holds epithelial cells together consists of a protein complex in which members of the cadherin family linked to various catenins are the principal components. delta-catenin is a mammalian brain protein in the Armadillo repeat superfamily with sequence similarity to the adherens junction protein p120(ctn). We found that delta-catenin can be immunoprecipitated as a complex with other components of the adherens junction, including cadherin and beta-catenin, from transfected cells and brain. The interaction with cadherin involves direct contact within the highly conserved juxtamembrane region of the COOH terminus, where p120(ctn) also binds. In developing mouse brain, staining with delta-catenin antibodies is prominent towards the apical boundary of the neuroepithelial cells in the ventricular zone. When transfected into Madin-Darby canine kidney (MDCK) epithelial cells delta-catenin colocalized with cadherin, p120(ctn), and beta-catenin. The Arm domain alone was sufficient for achieving localization and coimmunoprecipitation with cadherin. The ectopic expression of delta-catenin in MDCK cells altered their morphology, induced the elaboration of lamellipodia, interfered with monolayer formation, and increased scattering in response to hepatocyte growth factor treatment. We propose that delta-catenin can regulate adhesion molecules to implement the organization of large cellular arrays necessary for tissue morphogenesis.
将上皮细胞连接在一起的经典黏着连接由一种蛋白质复合物组成，其中与各种连环蛋白相连的钙黏蛋白家族成员是主要成分。δ-连环蛋白是犰狳重复超家族中的一种哺乳动物脑蛋白，其序列与黏着连接蛋白p120（ctn）相似。我们发现，δ-连环蛋白可以与黏着连接的其他成分（包括钙黏蛋白和β-连环蛋白）形成复合物，从转染细胞和大脑中免疫沉淀出来。与钙黏蛋白的相互作用涉及COOH末端高度保守的近膜区域内的直接接触，p120（ctn）也结合在该区域。在发育中的小鼠大脑中，用δ-连环蛋白抗体染色在脑室区神经上皮细胞的顶端边界处很明显。当转染到Madin-Darby犬肾（MDCK）上皮细胞中时，δ-连环蛋白与钙黏蛋白、p120（ctn）和β-连环蛋白共定位。仅Arm结构域就足以实现与钙黏蛋白的定位和共免疫沉淀。δ-连环蛋白在MDCK细胞中的异位表达改变了它们的形态，诱导了片状伪足的形成，干扰了单层形成，并增加了对肝细胞生长因子处理的散射。我们提出，δ-连环蛋白可以调节黏附分子，以实现组织形态发生所需的大型细胞阵列的组织。
