Aspects of Cadherin/Catenin Complexes

描述：本项目的长期目标是了解钙粘蛋白是如何 影响细胞行为。我们特别感兴趣的是 N-cadherin如何增加人类细胞运动和侵袭行为 上皮肿瘤细胞钙粘蛋白是细胞膜的跨膜成分， 粘附连接，上皮和其他细胞中的细胞-细胞粘附结构。 因此，粘附蛋白可能参与增加细胞增殖的想法， 运动性是一个新的问题。钙粘蛋白以组织特异性的方式表达， 正常组织我们的实验室发现， 上皮细胞的钙粘蛋白（在这种情况下，N-钙粘蛋白，而不是 正常表达的E-钙粘蛋白）导致细胞运动性增加 增加了入侵。 本提案的具体目标是侧重于了解 N-钙粘蛋白在调节细胞运动中起作用。具体而言，我们建议： 1.确定N-钙粘蛋白介导的细胞运动的分子基础。 2.应用转基因小鼠模型研究N-钙粘蛋白在肿瘤中的作用 进展 3.确定N-钙粘蛋白是否通过调节血管生成而在血管生成中起作用。 内皮细胞的运动性。 为了实现这些目标，我们将利用分子构建体，通常由 嵌合体分子。这些构建体将在细胞中表达， 观察它们对细胞行为和表型的影响。蛋白质 相互作用将由几种方法确定，包括 免疫共沉淀反应，在组织培养细胞中的共定位， 酵母双杂交分析还将分析蛋白质-蛋白质相互作用 通过将两种蛋白质的相互作用结构域共转染到真核细胞中 随后在完整细胞中共定位（免疫荧光）， 细胞提取物的免疫共沉淀。我们将使用鼠标模型系统， 检测在其他正常乳腺中表达N-钙粘蛋白的影响， 上皮细胞，以确定N-钙粘蛋白是否仅在 肿瘤细胞的周围环境。最后，我们将研究N-钙粘蛋白可能 在正常内皮细胞的运动中起作用。 我们预测，我们将清楚地确定区域的n-钙粘蛋白，介导细胞 运动性而不影响细胞粘附。这些知识可能会让我们 以产生可用于抑制肿瘤细胞运动性而不 抑制细胞粘附。这些试剂可能有助于防止转移 和/或内皮细胞的血管生成。

DESCRIPTION: The long-term goal of this project is to understand how cadherins function to influence cellular behavior. In particular, we are interested in how N-cadherin increases the cell motility and invasive behavior of human epithelial tumor cells. The cadherins are the transmembrane components of the adherens junction, a cell-cell adhesive structure in epithelia and other cells. Thus, the idea that an adhesion protein may be involved in increasing cell motility is a novel one. Cadherins are expressed in a tissue specific manner in normal tissues. Our laboratory discovered that expression of an inappropriate cadherin by an epithelial cell (in this case, N-cadherin rather than the normally expressed E-cadherin) resulted in a cell with increased cell motility and increased invasion. The specific aims of this proposal are focused on understanding the role N-cadherin plays in modulating cell motility. Specifically, we propose to: 1. Determine the molecular basis of N-cadherin-mediated cell motility. 2. Use a transgenic mouse model to investigate the role of N-cadherin in tumor progression. 3. Determine if N-cadherin plays a role in angiogenesis by modulating the motility of endothelial cells. To accomplish these goals, we will make use of molecular constructs, often made up of chimeric molecules. These constructs will be expressed in cells to observe their effect on cellular behavior and phenotype. Protein-protein interactions will be determined by several means which include coimmunoprecipitation reactions, co-localization in tissue culture cells and yeast two hybrid analysis. Protein-protein interactions will also be analyzed by co-transfecting interaction domains of two proteins into eukaryotic cells followed by co-localization in intact cells (immunofluorescence) and co-immunoprecipitation of cell extracts. We will use a mouse model system to examine the effects of expressing N-cadherin in otherwise normal breast epithelial cells to determine if N-cadherin influences cell behavior only in the contex of a tumor cell. Finally, we will examine the role N-cadherin may play in motility of normal endothelial cells. We predict we will clearly identify regions on n-cadherin that mediate cell motility without effecting cell adhesion. This knowledge may make it possible to generate reagents that could be used to inhibit tumor cell motility without inhibiting cell adhesion. Such reagents might be useful to prevent metastasis of tumor cells and/or angiogenesis of endothelial cells.