Cell biological mechanisms of gastrointestinal tract formation

胃肠道形成的细胞生物学机制

• 批准号: 8636129
• 负责人: Stephanie Woo
• 金额: $ 0.1万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-15 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8636129
• 关键词: Actins; Address; Affect; Animal Model; Area; Behavior; Biological; Biological Models; Biological Process; Cell Communication; Cell Surface Receptors; Cell Transplantation; Cells; Congenital Abnormality; Cues; Cytoskeleton; Defect; Development; Digestive System Disorders; Disease; Ectoderm; Embryo; Embryonic Development; Endoderm; Endoderm Cell; Ensure; EphA7 Receptor; Epithelial; Future; Gastrointestinal tract structure; Genetic Techniques; Germ Layers; Goals; Homeostasis; Homologous Gene; Human; Image; Immigration; Individual; Inflammation; Knowledge; LAR tyrosine phosphatase receptor; Label; Life; Ligands; Light; Malignant Neoplasms; Mediating; Mentors; Mesoderm; Mesoderm Cell; Methods; Microarray Analysis; Molecular Genetics; Monitor; Monomeric GTP-Binding Proteins; Morbidity - disease rate; Morphogenesis; Movement; Neoplasm Metastasis; Nodal; Organ; Other Genetics; Pattern; Play; Positioning Attribute; Process; Reporting; Research; Resolution; Role; Signal Transduction; Signaling Protein; Site; Specific qualifier value; Specificity; Staging; Surface; System; Techniques; Time; Training; Transcription factor genes; Transforming Growth Factor beta; Transgenic Organisms; Tube; Zebrafish; base; cell behavior; cell motility; fluorescence imaging; gain of function; gastrointestinal; gastrointestinal system; gastrulation; gene function; genetic regulatory protein; glucose metabolism; immune function; in vivo; insulin signaling; loss of function; malformation; migration; mortality; novel; polymerization; protein function; receptor; research study; tissue repair; transcription factor; tumor

DESCRIPTION (provided by applicant): The goal of this study is to identify the mechanisms regulating early endodermal cell migration and understand how cell movements contribute to the overall formation of the gastrointestinal tract. Although much progress has been made in identifying the transcription factors that specify endodermal cells, much less is known about the cell biological processes that occur subsequently, including the onset of cell motility. Shortly after specification, endodermal cells internalize to form the inner layer of the body during a process known as gastrulation. Using the zebrafish embryo as a model system, I will examine two aspects of endodermal cell migration - random directionality and contact-dependent repulsion. For these studies, I will use high-resolution fluorescence imaging of live embryos and a novel transgenic line that I developed that fluorescently labels the actin cytoskeleton. Preliminary evidence suggests that Nodal, a signaling protein already known to induce endodermal fate, can promote endodermal migration in a directionally random manner. I will characterize the effects of Nodal signaling on the actin cytoskeleton within endodermal cells, and I will identify the actin regulatory proteins that function to promote Nodal-induced motility. In the second specific aim, I will examine the mechanisms regulating contact-dependent repulsion. This is a process whereby migrating endodermal cells are repelled away from each other after making brief contact. Using both candidate and microarray- based approaches, I will attempt to identify the cell surface receptors that initiate contact repulsion as well as the cytoplasmic signaling proteins that act downstream of these receptors. Together, directionally random motility and contact repulsion appear to drive the dispersal of endodermal cells across the surface of the early embryo, after which these cells coalesce into a single gut tube. To understand the significance of this initial dispersal, I will use gain and loss of function techniques to interfere with normal endodermal migratory behavior and assess the effects on subsequent development of the gastrointestinal tract. In the course of this study, I will gain further expertise in vertebrate gut development, whole-embryo time-lapse imaging, and quantitative methods for examining in vivo cell migration. My primary mentor, Dr. Didier Stainier, and my co-mentor, Dr. Orion Weiner, will provide additional training in these areas to help me achieve my research goals. This study will shed light on a poorly appreciated aspect of gastrointestinal development and will form the basis for a future R-level application as I continue to explore the relationship between cell migration and organ development.

描述（由申请人提供）：这项研究的目的是确定调节早期内胚层细胞迁移的机制，并了解细胞运动如何有助于胃肠道的整体形成。尽管在识别指定内胚细胞的转录因子方面取得了很多进展，但对随后发生的细胞生物学过程的了解少得多，包括细胞运动的发作。规范后不久，内胚层细胞内部化以形成人体的内层，在称为胃肠道的过程中。使用斑马鱼胚作为模型系统，我将检查内胚细胞迁移的两个方面 - 随机方向性和接触依赖性排斥。在这些研究中，我将使用活胚的高分辨率荧光成像和一种新型的转基因线，我开发了荧光标记肌动蛋白细胞骨架的标签。初步证据表明，Nodal是已经已知会诱导内胚层命运的信号蛋白可以以方向随机的方式促进内胚层迁移。我将表征淋巴结信号传导对内胚层细胞内肌动蛋白细胞骨架的影响，并且我将确定肌动蛋白调节蛋白，这些蛋白质功能促进淋巴结诱导的运动。在第二个特定目的中，我将检查调节接触依赖排斥的机制。这是一个过程，在短暂接触后，迁移的内皮细胞彼此排斥。使用候选和基于微阵列的方法，我将尝试鉴定引发接触抑制的细胞表面受体以及这些受体下游作用的细胞质信号传导蛋白。总之，方向随机运动和接触式排斥似乎可以驱动内胚细胞在早期胚胎表面的分散，然后这些细胞将其聚集成单个肠管。为了了解这种初始分散的意义，我将使用功能技术的增益和丧失来干扰正常的内皮胚迁移行为，并评估对胃肠道随后发展的影响。 在这项研究的过程中，我将在脊椎动物肠道发展，全孔延时成像以及检查体内细胞迁移的定量方法方面获得进一步的专业知识。我的主要导师Didier Stainier博士和我的同事Orion Weiner博士将在这些领域提供其他培训，以帮助我实现研究目标。这项研究将阐明胃肠道发育的不佳方面，并将在我继续探索细胞迁移与器官发育之间的关系时为未来的R级应用奠定基础。