Cadherin Regulation in Dermal Endothelial Cells

真皮内皮细胞中钙粘蛋白的调节

• 批准号: 6929228
• 负责人: ANDREW P. KOWALCZYK
• 金额: $ 27.85万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-08-01 至 2009-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6929228
• 关键词: SDS polyacrylamide gel electrophoresis; angiogenesis; cadherins; cell adhesion molecules; cell membrane; cytoskeleton; gene expression; genetic regulation; histogenesis; inflammation; site directed mutagenesis; skin; vascular endothelium; western blottings

DESCRIPTION (provided by applicant): The cutaneous microcirculation plays a central role in a range of skin diseases that are characterized by epidermal hyperproliferation or cutaneous inflammation. Many of these diseases are typified by increased vascular permeability, leading to cutaneous edema and exacerbation of disease. In addition, altered vascular organization and/or neovascularization are associated with psoriasis, skin tumorigenesis, and with tissue remodeling during wound healing. Adhesive interactions between adjacent endothelial cells play a central role in both vascular permeability and in the reorganization and growth of endothelial cells during angiogenesis. VE-cadherin is a cell surface adhesion molecule specific to endothelial cells which plays a crucial role in endothelial growth control, vascular barrier function and in morphogenic events associated with angiogenesis. The extracellular domain of VE-cadherin mediates cell to cell contact, whereas the cytoplasmic tail of VE-cadherin functions as a scaffold for a series of proteins termed catenins, which couple VE-cadherin to actin and vimentin cytoskeletal networks. Although a great deal has been discovered about the molecular interactions that link VE-cadherin to the cytoskeleton, much less is known about how cell surface levels of VE-cadherin are regulated. Preliminary data from our laboratory leads to the hypothesis that the catenins, in addition to linking cadherins to the cytoskeleton, also regulate VE-cadherin presentation at the plasma membrane by regulating VE-cadherin internalization and degradation. Three specific aims are proposed. In the first aim, the ability of the catenin p120 to regulate VE-cadherin internalization and degradation will be tested. In the second aim, the assembly state of the cadherin catenin complex at the plasma membrane and in the endocytic compartment will be defined. In the third aim, specific sequences in the VE-cadherin tail that target the protein for internalization will be ablated using site directed mutagenesis, and the effect of these mutations on endothelial barrier function and branching morphogenesis will be determined. The long-term goal of these studies is to identify the molecular determinants that regulate VE-cadherin cell surface presentation, and thereby expose processes that could be therapeutically targeted to modulate endothelial barrier function and angiogenesis in the context of cutaneous disease.

描述（由申请人提供）： 皮肤微循环在一系列以表皮过度增殖或皮肤炎症为特征的皮肤疾病中起着核心作用。许多这些疾病的特征是血管通透性增加，导致皮肤水肿和疾病恶化。此外，改变的血管组织和/或新血管形成与牛皮癣、皮肤肿瘤发生以及伤口愈合过程中的组织重塑有关。相邻内皮细胞之间的粘附相互作用在血管通透性以及血管生成过程中内皮细胞的重组和生长中发挥着核心作用。 VE-钙粘蛋白是一种内皮细胞特异性的细胞表面粘附分子，在内皮生长控制、血管屏障功能以及与血管生成相关的形态发生事件中发挥着至关重要的作用。 VE-钙粘蛋白的胞外结构域介导细胞与细胞的接触，而 VE-钙粘蛋白的细胞质尾部充当一系列称为连环蛋白的蛋白质的支架，将 VE-钙粘蛋白与肌动蛋白和波形蛋白细胞骨架网络偶联。尽管人们已经发现了大量关于连接 VE-钙粘蛋白与细胞骨架的分子相互作用的信息，但人们对 VE-钙粘蛋白的细胞表面水平如何调节的了解却少之又少。我们实验室的初步数据得出这样的假设：连环蛋白除了将钙粘蛋白连接到细胞骨架之外，还通过调节 VE-钙粘蛋白内化和降解来调节 VE-钙粘蛋白在质膜上的呈递。提出了三个具体目标。第一个目标是测试连环蛋白 p120 调节 VE-钙粘蛋白内化和降解的能力。在第二个目标中，将定义钙粘蛋白连环蛋白复合物在质膜和内吞室中的组装状态。在第三个目标中，将使用定点诱变消除以蛋白质内化为目标的 VE-钙粘蛋白尾部中的特定序列，并且将确定这些突变对内皮屏障功能和分支形态发生的影响。这些研究的长期目标是确定调节 VE-钙粘蛋白细胞表面呈现的分子决定因素，从而揭示可在皮肤疾病中调节内皮屏障功能和血管生成的治疗目标过程。