Blood vessel tubulogenesis: Rasip1-directed GTPase signaling and cell polarity.

血管管发生：Rasip1 引导的 GTPase 信号传导和细胞极性。

基本信息

批准号：
8274559
负责人：
Ondine B Cleaver
金额：
$ 39.7万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-04-05 至 2016-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8274559
关键词：
Ablation Adhesions Affect Angioblast Aorta Apical Binding Biochemistry Biological Assay Blood Blood Vessels Cardiovascular system Cell Polarity Cell Shape Cell physiology Clinical Co-Immunoprecipitations Complex Cytoskeleton Defect Development Disease Dorsal Drug Design Embryo Endothelial Cells Extracellular Matrix Failure Future Genetic Goals Growth Guanosine Triphosphate Phosphohydrolases Heart In Situ Hybridization In Vitro Mass Spectrum Analysis Mediating Membrane Molecular Molecular Target Monomeric GTP-Binding Proteins Morphology Mus Mutant Strains Mice Outcome Outcome Study Pathway interactions Process Proteins Regulation Role Signal Pathway Signal Transduction Small Interfering RNA Staging Testing Time Tube Tumor Angiogenesis Wound Healing antiangiogenesis therapy apical membrane ezrin gain of function in vitro Model in vivo loss of function luminal membrane rho segregation tumor vasculogenesis

项目摘要

DESCRIPTION (provided by applicant): Formation of blood-carrying channels at the heart of blood vessels (lumen formation or 'tubulogenesis') is one of the most critical steps during cardiovascular development. To date, the molecular mechanisms underlying this process remain unclear. Understanding and ultimately controlling blood vessel growth are key goals of many clinical approaches, ranging from blocking vessels in tumor angiogenesis to promoting vessels in wound healing. Transcriptional profiling of embryonic endothelial cells (ECs) was carried out to discover factors that regulate blod vesel formation, and identified a GTPase-interacting protein called Rasip1. Rasip1 was found to be expressed specificaly in embryonic ECs, and ablation of Rasip1 in mice blocks embryonic vascular tubulogenesis and blood vessel formation. We showed those Rasip1 complexes with small GTPases and their effectors, to promote Cdc42 and Rac1, and suppress RhoA. Key defects in Rasip1-/- cords (E8.0-8.5) include: loss of angioblast cell polarity and of proper localization of the polarity determinant Par3, as well as disruption of 1integrin-mediated adhesion to ECM and of the cytoskeleton. The main hypothesis is that Rasip1 regulates distinct downstream GTPase signaling pathways, such as Rho, Rac and Cdc42, which regulate distinct cellular processes that coordinate to drive vascular tubulogenesis. This proposal asks how Rasip1-mediated cell polarity, contractility and adhesion influence endothelial tubulogenesis, and dissects pathways downstream of Rasip1 using mouse genetics, in vitro models and biochemistry. For analysis of mouse mutants, simple parameters will be assessed to study lumen formation in E8.0-8.5 mouse dorsal aortae (angioblast morphology and organization, as well as polarity and adhesion markers). Specific aims are: 1. To examine role of Rasip1-dependent cell polarity and mechanisms of apical/luminal membrane formation during vascular lumen formation (Par3 and Crb3). 2. To identify the cellular outcomes of the different Rasip1-regulated GTPase signaling pathways, Rho, Rac1 and Cdc42, during vascular lumen formation, and assess which pathways can rescue or exacerbate the Rasip1 null lumen failure. 3. To elucidate mechanism of Rasip1-dependent lumen formation via identification of lumen formation 'signaling complex' components. The short-term objective of these studies is to elucidate Rasip1 regulated pathways and further our understanding of cardiovascular development. The long-term objective is to find new molecular targets to block blood vessel growth in disease, such as in growing tumors, by blocking lumen formation. ! PUBLIC HEALTH RELEVANCE: Blood vessel growth and function depend on the formation of blood-carrying channels at their core, via a process called 'lumen formation' or 'tubulogenesis'. Here, we investigate a molecule, Rasip1, and its regulation of the activity of small molecular switches called GTPases that control endothelial cell shape and organization during vascular tubulogenesis. The ultimate goal is to find new molecular targets to block blood vessel growth in disease, such as in growing tumors, by blocking lumen formation. !

描述（由申请人提供）：在血管中心（管腔形成或“微管发生”）的血液携带通道的形成是心血管发育过程中最关键的步骤之一。迄今为止，该过程的基础机制尚不清楚。理解并最终控制血管生长是许多临床方法的关键目标，从阻断肿瘤血管生成的血管到促进伤口愈合中的血管。进行了胚胎内皮细胞（EC）的转录分析，以发现调节Blod Vesel形成的因素，并鉴定出一种称为RASIP1的GTPase相互作用蛋白。发现RASIP1在胚胎EC中表达了特异性，而RASIP1在小鼠中的消融却阻止了胚胎血管微管发生和血管形成。我们展示了那些具有小GTPases及其效应子的RASIP1复合物，以促进Cdc42和Rac1，并抑制Rhoa。 RASIP1 - / - 绳索中的主要缺陷（E8.0-8.5）包括：血管细胞细胞极性的丧失和极性决定剂PAR3的适当定位，以及1integrin介导的ECM和细胞骨架的1型蛋白介导的粘附。主要假设是RASIP1调节不同的下游GTPase信号通路，例如RHO，RAC和CDC42，这些途径调节了不同的细胞过程，这些过程是坐标以驱动血管肾小管发生的。该建议询问RASIP1介导的细胞极性，收缩力和粘附如何影响内皮小管发生，并使用小鼠遗传学，体外模型和生物化学剖析RASIP1下游的途径。为了分析小鼠突变体，将评估简单的参数以研究E8.0-8.5小鼠背主动脉（血管细胞形态和组织以及极性和粘附标记）中的管腔形成。具体目的是：1。检查血管腔形成期间的RASIP1依赖性细胞极性和顶端/腔膜形成的机制（PAR3和CRB3）。 2。在血管管腔形成期间，要确定不同RASIP1调节的GTPase信号通路的细胞结局，RHO，RAC1和CDC42，并评估哪些途径可以营救或加剧RASIP1 NULL管腔失败。 3。通过鉴定腔形成“信号传导复合物”成分来阐明RASIP1依赖性管腔形成的机理。这些研究的短期目标是阐明RASIP1规范途径，并进一步了解心血管发育。长期目标是找到新的分子靶标，以通过阻断管腔形成来阻止疾病（例如生长肿瘤）中的血管生长。呢公共卫生相关性：血管生长和功能取决于通过称为“流明形成”或“微管发生”的过程，取决于其核心的血液携带通道的形成。在这里，我们研究了一个分子RASIP1，及其调节小分子开关的活性称为GTPases，该开关在血管管发生过程中控制内皮细胞的形状和组织。最终目标是找到新的分子靶标，以通过阻断管腔形成来阻止疾病（例如生长肿瘤）中的血管生长。呢