Endothelial lineage specification and differentiation in vertebrate embryos

脊椎动物胚胎的内皮谱系规范和分化

• 批准号: 8105408
• 负责人: Suk-Won Jin
• 金额: $ 23.68万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8105408
• 关键词: Endothelial; lineage; specification; differentiation; vertebrate

DESCRIPTION (provided by applicant): Recent advances in cell culture studies provide invaluable insights on how the endothelial lineage is modulated by diverse signaling pathways. However, the cellular and molecular mechanisms that regulate the initial specification of endothelial lineage within developing embryos are largely unknown. To delineate the developmental origin of the endothelial lineage, we previously generated a laser assisted single-cell resolution fate map in the most ventral region of zebrafish gastrula that provided the first detailed distribution pattern of the hemangioblast, a hypothetical common precursor for both endothelial and hematopoietic lineages. Additionally, in our previous study, we found that hemangioblasts only produce a subset of the endothelial lineage, while the majority originates from endothelial specific progenitors, indicating the heterogeneous developmental origin of endothelial lineage. Our recent observation that avascular mutant embryos recover from their initial lack of endothelial cells later in development, further supports this idea, and suggests that the progenitors of the endothelial lineage consist of spatially and temporally distinct subpopulations. In this proposal, by using a multifaceted approach, we plan to delineate the heterogeneity of endothelial progenitors, and elucidate how distinct subpopulations of endothelial progenitors respond differently to Wnt signaling, which, based on our preliminary data, appears to be a key modulator of endothelial lineage specification. Three specific aims are designed to achieve these goals. First, we will expand our single-cell resolution fate map analyses to test whether hemangioblasts exist in other areas of the gastrula. This approach will also determine the embryo-wide distribution patterns of progenitors with endothelial potential, and will allow us to identify subpopulations of endothelial progenitors with distinct developmental potentials. In the second aim, we plan to define the cellular origin of endothelial cells involved in the vascular recovery of avascular mutant embryos. The analyses on two of previously isolated avascular zebrafish mutants will identify subpopulations of progenitors that generate endothelial lineages in a temporally distinctive manner. Lastly, we will examine whether subpopulations of endothelial progenitors respond differently to Wnt signaling by using transgenic lines that are capable of manipulating the time and place of Wnt activity. Understanding the developmental heterogeneity of the endothelial lineage will provide invaluable insights on how endothelial lineage is established during development. In addition, the proposed research will enhance our knowledge on how distinct cell types emerge from pluripotent progenitors during development. Furthermore, the proposed research may provide essential groundwork for the therapeutic application of pluripotent progenitors with the ability to ameliorate clinical conditions affecting the circulatory system in humans. PUBLIC HEALTH RELEVANCE. The proposed research aims to understand how endothelial cells emerge during development from progenitors. Information acquired from the proposed research will enhance our current knowledge on the mechanisms that regulate the differentiation of pluripotent progenitors (for example, stem cells) into specific cell types. Furthermore, it will also help us to understand the etiology of many vascular diseases and design a better way of using pluripotent progenitors for the therapeutic purposes.

描述（由申请人提供）：细胞培养研究的最新进展提供了关于内皮谱系如何通过多种信号通路调节内皮谱系的宝贵见解。但是，在发育中的胚胎中调节内皮谱系初始规范的细胞和分子机制在很大程度上是未知的。为了描绘内皮谱系的发育起源，我们先前在斑马鱼胃的最腹侧区域中产生了激光辅助的单细胞分辨率命运图，该图提供了植血性细胞的第一个详细分布模式，这是一种假设的内皮和血压内皮层中的假设共同的前体。此外，在我们先前的研究中，我们发现血管细胞仅产生内皮谱系的一部分，而大多数人来自内皮特异性祖细胞，表明内皮谱系的异质发育起源。我们最近的观察结果是，血管突变体胚胎后来在发育后的最初缺乏内皮细胞中恢复，进一步支持了这一想法，并表明内皮谱系的祖细胞由空间和时间上不同的亚群组成。在此提案中，通过使用多方面的方法，我们计划描述内皮祖细胞的异质性，并阐明内皮祖细胞对Wnt信号的反应不同，基于我们的初步数据，这似乎是内皮层面的关键模块。旨在实现这些目标的三个具体目标。首先，我们将扩展单细胞分辨率的命运图分析，以测试胃的其他区域中是否存在血管细胞。这种方法还将确定具有内皮潜力的祖细胞的胚胎范围范围的分布模式，并使我们能够鉴定具有具有不同发育潜力的内皮祖细胞的亚群。在第二个目标中，我们计划定义与血管突变胚胎血管恢复有关的内皮细胞的细胞来源。对两个先前分离的血管性斑马鱼突变体的分析将确定以时间独特的方式产生内皮谱系的祖细胞的亚群。最后，我们将检查内皮祖细胞的亚群是否通过使用能够操纵Wnt活性的时间和地点的转基因线对Wnt信号的反应。了解内皮谱系的发育异质性将提供有关在发育过程中如何建立内皮血统的宝贵见解。此外，拟议的研究将增强我们对在发育过程中多能祖细胞中不同细胞类型如何出现的知识。此外，拟议的研究可能为多能祖细胞的治疗应用提供基本的基础，并能够改善影响人类循环系统的临床状况。公共卫生相关性。拟议的研究旨在了解祖细胞发育过程中内皮细胞如何出现。从拟议的研究中获得的信息将增强我们对调节多能祖细胞（例如干细胞）分化为特定细胞类型的机制的当前知识。此外，它还将帮助我们了解许多血管疾病的病因，并设计一种将多能祖细胞用于治疗目的的更好方法。