Reactive Oxygen Species and Endothelial Migration

活性氧和内皮迁移

基本信息

批准号：
7379914
负责人：
Masuko Ushio-Fukai
金额：
$ 37.63万
依托单位：
UNIVERSITY OF ILLINOIS AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2006
资助国家：
美国
起止时间：
2006-03-15 至 2011-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7379914
关键词：
Actins Adenoviruses Adherens Junction Adhesions Angiogenic Factor Binding Binding Proteins Binding Sites Biological Assay Blood capillaries Blood flow Cell Adhesion Molecules Cell-Cell Adhesion Cells Complementary DNA Complex Confocal Microscopy Coupling Data Development E-Cadherin Endothelial Cells Event Goals Growth Hindlimb Hydrogen Peroxide In Vitro Ischemia Laboratories Link Localized Mediating Modeling Molecular Monomeric GTP-Binding Proteins Morphogenesis Mus NAD(P)H oxidase Peptides Production Protein Overexpression Reactive Oxygen Species Recovery Recruitment Activity Regulation Research Personnel Role Scaffolding Protein Signal Pathway Signal Transduction Signaling Molecule Small Interfering RNA Source Specificity Stress Tyrosine Phosphorylation Vascular Endothelial Growth Factor Receptor-2 Vascular Endothelial Growth Factors Wild Type Mouse Work Wound Healing angiogenesis base cadherin 5 capillary cell motility in vivo migration mutant novel novel therapeutics postnatal programs receptor response response to injury scaffold wound yeast two hybrid system

项目摘要

Endothelial cell (EC) migration is a key event for endothelial wound repair and angiogenesis. VEGF is a potent stimulator for EC migration primarily through the VEGF type2 receptor (VEGFR2). In quiescent ECs, one of the initial responses to stimulate endothelial migration by VEGF is the loosening of stable cell-cell contacts which is regulated by tyrosine phosphorylation of VE-cadherin. We showed that VEGF stimulates Rac1-dependent gp91phox-based NAD(P)H oxidase and that reactive oxygen species (ROS) are involved in VEGFR2-mediated signaling linked to EC migration. Underlying molecular mechanisms are poorly understood. We recently identified IQGAP1 as a novel VEGFR2 binding protein. It functions as a scaffold protein that controls cell motility and morphogenesis by interacting with cytoskeletal and cell-cell adhesion proteins including active Rac1 and E-cadherin. We also found that: 1) IQGAP1 expression is increased in the newly-formed capillary ECs in a mouse hindlimb ischemia model of angiogenesis; 2) Overexpression of IQGAP1 increases basal Rac1 activity, ROS production and cell migration in ECs; 3) VEGF promotes recruitment of activated VEGFR2 and Rac1 to the IQGAP1-VE-cadherin complex at adherens junctions, which may promote ROS-dependent loss of cell-cell contacts and subsequent EC migration; 4) Wound assays reveal that IQGAP1 colocalizes with active VEGFR2 and gp91phox at the leading edge inactively migrating ECs. We thus hypothesize that IQGAP1 functions as a VEGFR2 binding scaffold protein to link ROS-dependent signaling with VEGF-mediated endothelial migration. Aim1 will examine whether IQGAP1 functionally interacts with VEGFR2 and Rac1 to couple VEGFR2 to ROS-dependent signaling linked to EC migration. Aim2 will examine whether IQGAP1 functions as a scaffold to recruit activated VEGFR2 and Rac1 to adherens junctions through binding to VE-cadherin, thereby facilitating ROS-dependent loss of cell-cell contacts, which initiates EC migration. Aim3 will examine the scaffolding role of IQGAP1 in targeting VEGFR2 and NAD(P)H oxidase to the leading edge during directed cell migration. Aim4 will assess the functional significance of IQGAP1 in vivo using mouse hindlimb ishcemia model. The long-term goal is to understand the molecular mechanisms by which ROS regulate EC migration in the context of angiogenesis and endothelial wound repair, which should facilitate the development of new therapeutic strategies.

内皮细胞（EC）迁移是内皮伤口修复和血管生成的关键事件。 VEGF是一个 EC迁移的有效刺激器主要通过VEGF Type2受体（VEGFR2）。在静止的EC中 VEGF刺激内皮迁移的最初反应之一是稳定细胞细胞的松动通过VE-钙粘着蛋白的酪氨酸磷酸化调节的接触。我们表明VEGF刺激了 Rac1依赖性GP91PHOX基于NAD（P）H氧化酶，而活性氧（ROS）参与 VEGFR2介导的信号与EC迁移有关。潜在的分子机制很差理解。我们最近将IQGAP1鉴定为一种新型的VEGFR2结合蛋白。它充当脚手架通过与细胞骨架和细胞 - 细胞粘附相互作用来控制细胞运动和形态发生的蛋白质包括活性RAC1和E-钙粘蛋白在内的蛋白质。我们还发现：1）IQGAP1表达在小鼠后肢缺血模型中新形成的毛细血管ECS； 2）过表达 IQGAP1增加了EC中的基础Rac1活性，ROS产生和细胞迁移； 3）VEGF促进将激活的VEGFR2和RAC1招募到Adherens结合的IQGAP1-VE-钙粘蛋白复合蛋白，这可能会促进ROS依赖性细胞接触的丧失和随后的EC迁移； 4）伤口测定表明IQGAP1与主动vegfr2和GP91Phox在前沿不活跃地共定位迁移EC。因此，我们假设IQGAP1充当VEGFR2结合支架蛋白与连接 ROS依赖性信号传导，带有VEGF介导的内皮迁移。 AIM1将检查IQGAP1是否在功能上与VEGFR2和Rac1相互作用，将VEGFR2与与EC相关的ROS依赖性信号迁移。 AIM2将检查IQGAP1是否作为招募激活的VEGFR2和Rac1的脚手架。通过与VE-钙粘着蛋白结合的粘附连接，从而促进了ROS依赖性细胞细胞的损失联系人，启动EC迁移。 AIM3将检查IQGAP1在靶向中的脚手架作用在定向细胞迁移期间，VEGFR2和NAD（P）H氧化酶降至前缘。 AIM4将评估 IQGAP1在体内使用小鼠后肢等激素模型的功能意义。长期目标是了解在血管生成中ROS调节EC迁移的分子机制和内皮伤口修复，这应该有助于发展新的治疗策略。