Hox genes in the development of respiratory circuits

Hox 基因在呼吸回路发育中的作用

• 批准号: 8738732
• 负责人: Polyxeni Philippidou
• 金额: $ 8.64万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-29 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8738732
• 关键词: Address; Affect; Amyotrophic Lateral Sclerosis; Award; Behavior; Biological Assay; Biological Neural Networks; Birth; Brain Stem; Breathing; Cause of Death; Cell Nucleus; Central Sleep Apnea; Cervical spinal cord structure; Dasen; Defect; Development; Disease; Ensure; Environment; Equipment; Excision; Exhibits; Extinction (Psychology); Frequencies; Functional disorder; Gene Expression; Gene Expression Profiling; Gene Targeting; Genes; Genetic; Goals; Individual; Interneurons; Label; Lead; Mammals; Maps; Medical center; Mentors; Methods; Molecular; Molecular Genetics; Motor; Motor Neurons; Movement; Mus; Muscle; Muscle Contraction; Muscular Dystrophies; Neurons; Neurosciences; Pathway interactions; Perinatal; Phase; Physiological; Plethysmography; Population; Positioning Attribute; Proteins; Rabies virus; Research; Research Personnel; Respiration Disorders; Respiratory Diaphragm; Respiratory Failure; Respiratory physiology; Role; Sleep Apnea Syndromes; Source; Specificity; Spinal; Spinal Cord; Synapses; System; Techniques; Tissue-Specific Gene Expression; Training; Universities; Vertebrates; Viral; Virus; Work; alternative treatment; axon guidance; base; career development; cell type; experience; improved; in vivo; insight; motor neuron development; nerve supply; new therapeutic target; protein expression; public health relevance; research study; respiratory

DESCRIPTION (provided by candidate): Breathing is a vital motor behavior that relies on diaphragm muscle contractions in mammals. The frequency and amplitude of breathing movements is controlled by neural networks residing in the brainstem and spinal cord. Degeneration of these networks leads to respiratory disorders, such as central sleep apneas, and, eventually, respiratory failure. My long term goal is to uncover the basic principles underlying respiratory circuit assembly so that we can begin to consider alternative treatment methods for respiratory dysfunction. A conundrum in the study of respiratory neural networks is that while significant progress has been made in defining the rhythmogenic circuits in the brain stem, the developmental origins, molecular identity and connectivity of spinal cord respiratory neurons remain unknown. Overall, the proposed research aims to define the genetic and molecular pathways that underlie spinal respiratory network assembly. We have recently demonstrated that the development of phrenic motor column (PMC) neurons in the cervical spinal cord, which innervate the diaphragm, requires the sustained activity of Hox5 genes. Mice lacking Hox5 genes in motor neurons (MNs) die of respiratory failure at birth and exhibit defects in multiple aspects of PMC identity, including clustering, axon guidance and diaphragm innervation. During the mentored part of this award, the role of Hox5 genes in PMC MNs will be further explored. Differential gene expression analysis will be carried out in order to identify genes acting downstream of Hox5 proteins to regulate distinct aspects of PMC development (Aim 1). Additionally, transsynaptic virus-based tracing approaches will be implored to examine how Hox5 removal from MNs affects the establishment of premotor inputs to the PMC (Aim 2). During the independent phase of the award, the role of Hox genes and their downstream targets in spinal cord respiratory interneuron development and connectivity will be examined (Aim 3). Addressing this question will rely heavily on genetic approaches, transsynaptic circuit labeling techniques and physiological respiratory assays, in which expertise will be acquired during the K99 phase. The mentored part of the research will be performed at the Dasen and Fishell labs at NYU Medical Center, an outstanding research environment that will provide all the equipment and facilities required for the proposed experiments. In addition, Dr. Kinkead at Laval University will act as a consultant and will provide training in the technique of plethysmography. I have assembled a committee who will oversee my progress and provide technical and intellectual input during the mentored part of the award. My previous experience in molecular neuroscience, in combination with a rigorous training plan, will ensure the successful completion of the proposed research aims, while the career development activities during the K99 phase of the award will facilitate a smooth transition to an independent position.

描述（由候选人提供）：呼吸是一种至关重要的运动行为，依赖于哺乳动物的膜片肌肉收缩。呼吸运动的频率和振幅由位于脑干和脊髓中的神经网络控制。这些网络的退化会导致呼吸系统疾病，例如中央睡眠呼吸暂停，最终导致呼吸衰竭。我的长期目标是揭示呼吸回路组件的基本原理，以便我们可以开始考虑用于呼吸障碍的替代治疗方法。呼吸神经网络研究中的一个难题是，尽管在定义脑干中的节奏电路方面取得了重大进展，但脊髓呼吸神经元的发育起源，分子认同和连通性仍然未知。总体而言，拟议的研究旨在定义脊柱呼吸网络组件构成的遗传和分子途径。我们最近证明，支配diaphragm的颈椎脊髓中phrenic运动柱（PMC）神经元的发展需要HOX5基因的持续活性。运动神经元中缺乏HOX5基因（MNS）出生时呼吸衰竭的小鼠在PMC认同的多个方面表现出缺陷，包括聚类，轴突引导和膜片神经支配。在该奖项的指导部分期间，将进一步探讨HOX5基因在PMC MN中的作用。将进行差异基因表达分析，以确定HOX5蛋白下游作用的基因以调节PMC发育的不同方面（AIM 1）。此外，将恳求基于透射性病毒的跟踪方法研究如何从MN中删除HOX5如何影响PMC的前者输入（AIM 2）。在该奖项的独立阶段，将检查HOX基因及其下游靶标在脊髓呼吸中的内神经元发展和连通性中的作用（AIM 3）。解决这个问题将在很大程度上依赖于遗传方法，经突触电路标记技术和生理呼吸测定，其中将在K99阶段获得专业知识。这项研究的指导部分将在纽约大学医学中心的Dasen和Fishell Labs进行，这是一个出色的研究环境，将提供拟议实验所需的所有设备和设施。此外，拉瓦尔大学（Laval University）的金克德（Kinkead）博士将担任顾问，并将提供有关综合学技术的培训。我组建了一个委员会，该委员会将监督我的进步，并在奖项的指导部分期间提供技术和知识投入。我以前在分子神经科学方面的经验，结合了严格的培训计划，将确保成功完成拟议的研究的目的，而奖励的K99阶段期间的职业发展活动将有助于平稳过渡到独立职位。