Analysis of Ret signaling in Drosophila enteric nervous system development.

果蝇肠神经系统发育中的 Ret 信号传导分析。

• 批准号: 8180786
• 负责人: Thomas Kidd
• 金额: $ 41.44万
• 依托单位: UNIVERSITY OF NEVADA RENO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8180786
• 关键词: Ablation; Adult; Affect; Animal Model; Antibodies; Binding; Bioinformatics; Biological Assay; Biological Models; Birth; Cells; Congenital Megacolon; Data; Destinations; Diabetes Mellitus; Documentation; Drosophila genus; Drug Delivery Systems; Embryo; Enteral; Enteric Nervous System; Family; Family member; Gastrointestinal tract structure; Genes; Genetic; Homologous Gene; Human; Immigration; In Vitro; Intestinal Cancer; Intestines; Invertebrates; Label; Lasers; Lead; Length; Ligand Binding; Ligands; Messenger RNA; Modeling; Molecular; Molecular Mechanisms of Action; Mus; Mutate; Mutation; Nerve; Nervous system structure; Neurons; Oncogenes; Operative Surgical Procedures; Organism; Parkinson Disease; Pathway interactions; Pattern; Peripheral Nervous System; Play; Process; Protein Binding; Proteins; Reagent; Receptor Protein-Tyrosine Kinases; Regulation; Relative (related person); Reporter; Research; Role; Signal Pathway; Signal Transduction; Spinal Cord; Testing; Therapeutic; Time; Tissues; Transgenic Organisms; Transplantation; axon guidance; base; cell motility; fly; genetic analysis; glial cell-line derived neurotrophic factor; in vivo; insight; mRNA Expression; migration; movie; nerve stem cell; nerve supply; nervous system development; neurotrophic factor; novel; novel therapeutic intervention; progenitor; promoter; proto-oncogene protein c-ret; receptor; relating to nervous system; time use; tissue culture; tissue/cell culture

DESCRIPTION (provided by applicant): About one in five thousand babies are born lacking neurons in the lowest part of the intestine. This condition is known as Hirschsprung Disease (HSCR) and requires corrective surgery. The progenitors of the affected neurons are born adjacent to the developing spinal cord and subsequently migrate to populate the entire length of the digestive tract, forming the enteric nervous system (ENS). The neural precursors use a receptor tyrosine kinase, RET, to detect and migrate towards a chemoattractive ligand, Glial Cell Line-Derived Neurotrophic Factor (GDNF). Genetic analysis in humans and mice supports a central role for RET signaling in HSCR, yet the actual role in vivo is under debate. A major challenge for the ENS field is to identify the molecular signals required for ENS formation in vivo. We believe that using Drosophila, with its powerful genetics, we can uncover these signals. Preliminary data indicates that Drosophila Ret is required for ENS formation, and we have identified an additional, parallel signaling pathway. Specific aim #1 will confirm and extend these findings. There is a remarkable conservation of molecular function between invertebrates and humans, so we believe our results will be relevant to HSCR in humans. Straightforward genetic analysis will determine whether Ret and a novel unrelated pathway are required for migration, proliferation, differentiation or axon guidance of ENS cells in vivo (aim #1). This information will be relevant to HSCR, and to adult ENS conditions, such as seen in diabetes. We have identified a candidate co-receptor and ligand and are testing these in tissue culture for physical association and signaling potential (specific aim #2). This could create an opportunity to analyze GDNF signaling in a simple organism, which would have relevance to non-ENS conditions such as Parkinson's disease. We will also develop new reagents for studying Drosophila ENS formation based on Ret promoter analysis (specific aim #3). Preliminary evidence suggests that the parallel signaling pathway we have uncovered will be relevant to vertebrate ENS formation. Our research may offer novel therapeutic approaches to HSCR, including factors necessary for successful enteric neuron transplantation. PUBLIC HEALTH RELEVANCE: The Ret gene plays a central role formation of the enteric (gut) nervous system, being frequently mutated in Hirschsprung's Disease (HSCR). Despite the contribution of animal models to our understanding of HSCR, no invertebrate model has yet been established. This proposal aims to develop a Drosophila model of HSCR with the aim of elucidating the basic mechanisms of action of Ret and interacting genes.

描述（由申请人提供）：大约五千分之一的婴儿出生时肠道最下部缺乏神经元。这种情况称为先天性巨结肠症 (HSCR)，需要进行矫正手术。受影响神经元的祖细胞出生于发育中的脊髓附近，随后迁移到消化道的整个长度，形成肠神经系统（ENS）。神经前体细胞使用受体酪氨酸激酶 RET 来检测并向化学吸引配体、胶质细胞系衍生神经营养因子 (GDNF) 迁移。人类和小鼠的遗传分析支持 RET 信号在 HSCR 中的核心作用，但其在体内的实际作用仍存在争议。 ENS 领域的一个主要挑战是识别体内 ENS 形成所需的分子信号。我们相信，利用果蝇及其强大的遗传学，我们可以发现这些信号。初步数据表明，果蝇 Ret 是 ENS 形成所必需的，我们已经确定了一条额外的平行信号通路。具体目标#1将确认并扩展这些发现。无脊椎动物和人类之间的分子功能存在显着的保守性，因此我们相信我们的结果将与人类的 HSCR 相关。直接的遗传分析将确定 ENS 细胞在体内的迁移、增殖、分化或轴突引导是否需要 Ret 和新的不相关途径（目标#1）。此信息将与 HSCR 和成人 ENS 病症相关，例如糖尿病。我们已经确定了候选共受体和配体，并正在组织培养中测试它们的物理关联和信号传导潜力（具体目标#2）。这可以创造一个机会来分析简单生物体中的 GDNF 信号传导，这可能与帕金森病等非 ENS 疾病相关。我们还将开发基于 Ret 启动子分析的新试剂来研究果蝇 ENS 的形成（具体目标#3）。初步证据表明，我们发现的平行信号通路将与脊椎动物 ENS 的形成相关。我们的研究可能为 HSCR 提供新的治疗方法，包括成功肠神经元移植所需的因素。 公共健康相关性：Ret 基因在肠神经系统的形成中发挥着核心作用，在先天性巨结肠症 (HSCR) 中经常发生突变。尽管动物模型对我们理解 HSCR 做出了贡献，但尚未建立无脊椎动物模型。本提案旨在开发 HSCR 的果蝇模型，以阐明 Ret 和相互作用基因的基本作用机制。