Role of Notch in Artery Development

描述（由申请人提供）：Notch信号通路的组分对于胚胎发生期间许多细胞类型的发育至关重要。此外，Notch信号传导组分的突变与多种人类疾病相关，包括影响心血管功能的疾病。在血管系统中，Notch受体在动脉内皮细胞中特异性表达，并在定义动脉粥样硬化中起关键作用。 身份Notch信号传导对于协调新血管萌芽或血管生成期间的尖端和柄细胞行为也很重要。我们以前的工作使用斑马鱼作为模型系统是在动脉分化和血管生成过程中定义Notch的作用。重要的是，我们过去和现在的研究表明，这些是通过不同的受体和配体组合控制的不同过程。此外，Notch在这些过程中的激活是动态的，发生在不同的发育阶段和不同的内皮亚型。因此，在这些情况中的每一种情况下，可能存在由Notch控制的不同的细胞输出和形态发生反应。然而，在不同的情况下，哪些靶基因介导Notch功能尚不清楚。为了确定血管系统中的功能性Notch靶点，我们提出了两个独立目标的研究。在目标1中，我们将研究候选转录抑制因子的要求，我们已经发现依赖于Notch在斑马鱼动脉内皮细胞。这些研究将依赖于应用位点特异性核酸酶来产生这些基因缺陷的敲除斑马鱼品系，然后进行详细的表型和上位性分析。这些研究将利用我们丰富的专业知识，使用斑马鱼进行复杂的遗传分析，再加上高含量的表型分析。在目标2中，我们将确定人动脉内皮细胞中NOTCH 1受体的直接靶点，以更好地了解Notch激活如何编程动脉身份。总之，这些研究将使我们了解Notch如何在不同的环境中影响内皮细胞的行为和分化。

DESCRIPTION (provided by applicant): Components of the Notch signaling pathway are essential for the development of numerous cell types during embryogenesis. Furthermore, mutations in Notch signaling components are associated with a variety of human diseases, including those affecting cardiovascular function. Within the vascular system, Notch receptors are expressed specifically in arterial endothelial cells and play a crucial role in defining artery identity. Notch signaling is also important for coordinating tip and stalk cell behaviors during th sprouting of new blood vessels, or angiogenesis. Our previous work using the zebrafish as a model system was instrumental in defining the roles of Notch during both artery differentiation and angiogenesis. Importantly, our past and current studies suggest that these are distinct processes governed through different receptor and ligand combinations. Additionally, Notch activation during these processes is dynamic, occurring at different developmental stages and in different endothelial subtypes. Thus, it is likely that there are distinct cellular outputs and morphogenetic responses controlled by Notch in each of these contexts. However, what the target genes are to mediate Notch function in different contexts is not known. To identify functional Notch targets in the vascular system, we propose studies encompassed in two separate Aims. In Aim 1, we will investigate the requirements of candidate transcriptional repressors that we have found are dependent on Notch in arterial endothelial cells in zebrafish. These studies will rely on the application of site-specific nucleases to generate knockout zebrafish lines deficient for these genes, followed by detailed phenotypic and epistasis analysis. These studies will leverage our vast expertise using the zebrafish for complex genetic analyses coupled with high content phenotypic analysis. In Aim 2, we will identify direct targets of the NOTCH1 receptor in human arterial endothelial cells to better understand how Notch activation programs artery identity. Taken together, these studies will allow us to understand how Notch may effect endothelial cell behaviors and differentiation in distinct contexts.