Genetic Control of Phrenic Motor Neuron Development and Maintenance

膈运动神经元发育和维持的遗传控制

基本信息

批准号：
10323654
负责人：
Polyxeni Philippidou
金额：
$ 34.47万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10323654
关键词：
Address Adult Air Movements Amyotrophic Lateral Sclerosis Automobile Driving Behavior Behavioral Assay Binding Sites Biological Assay Birth Brain Stem Breathing CRISPR/Cas technology Cause of Death Cells Cervical spinal cord structure ChIP-seq Collagen Defect Development Disease Electrophysiology (science)Embryo Enhancers Excision Exhibits Frequencies Genes Genetic Genetic Diseases Genetic Models Genetic Transcription Goals HOX protein High-Throughput Nucleotide Sequencing Homeobox Genes Interneurons Lead Life Limb structure Lung Maintenance Mammals Maps Mediating Metabolic Methodology Methods Molecular Motor Motor Activity Motor Neuron Disease Motor Neurons Movement Mus Muscle Muscular Dystrophies Mutant Strains Mice Neurodegenerative Disorders Neurons Pathway interactions Pattern Perinatal mortality demographics Plethysmography Predisposition Proteins Regulatory Element Respiration Disorders Respiratory Diaphragm Respiratory Failure Respiratory physiology Rett Syndrome Role Sleep Apnea Syndromes Spinal Spinal Cord Spinal cord injury Sudden infant death syndrome Synapses Testing Transgenic Mice Vertebrates alternative treatment axon guidance base body position cofactor developmental disease genetic approach improved in vivo insight motor behavior motor neuron development nerve supply neural circuit neural network new therapeutic target programs promoter protein function respiratory transcription factor transcription factor Oct-6 transcriptome sequencing

项目摘要

Breathing is the most fundamental motor behavior for terrestrial vertebrates. The frequency and amplitude of breathing movements are controlled by neural networks residing in the brainstem and spinal cord. In mammals, contraction of the diaphragm muscle is essential for driving airflow into the lungs during inspiration. Despite the complexity of the neural networks that regulate respiratory rhythms, diaphragm contraction is controlled by a single motor input, the activity of motor neurons (MNs) within the Phrenic Motor Column (PMC) in the cervical spinal cord. Loss of PMC neurons is the primary cause of death in degenerative MN diseases such as amyotrophic lateral sclerosis (ALS) and spinal cord injuries. Despite their essential role, the molecular determinants of PMC neuron identity are largely unknown. We have found that the development of PMC neurons requires the sustained activity of Hox5 transcription factors. Mice lacking Hox5 genes in MNs die of respiratory failure at birth and exhibit defects in multiple aspects of PMC identity, including cell body position, axon guidance and diaphragm innervation. In this proposal we will investigate the function of Hox5 genes in determining and maintaining phrenic MN identity. In Aim 1 we will determine temporally distinct functions of Hox5 proteins in phrenic MNs and how phrenic MN identity is maintained throughout lifetime. In Aim 2 we will define how Hox5 genes control phrenic MN specification at the transcriptional level. In Aim 3 we will identify direct Hox5 effectors and dissect their regulatory mechanisms. We have developed an integrative methodology encompassing genetic models, high-throughput sequencing, electrophysiology and behavioral assays, such as plethysmography, to address these questions in vivo. The overarching goal of this proposal is to uncover the basic principles underlying phrenic MN specification and maintenance so that we can begin to consider alternative treatment methods for respiratory dysfunction.

呼吸是陆生脊椎动物最基本的运动行为。频率和振幅呼吸运动由位于脑干和脊髓中的神经网络控制。在哺乳动物中， diaphragm肌肉的收缩对于在灵感期间将气流驱逐到肺部至关重要。尽管有调节呼吸节律的神经网络的复杂性，隔膜收缩受A控制单电机输入，颈椎运动柱（PMC）内运动神经元（MNS）的活性脊髓。 PMC神经元的丧失是退化性MN疾病中死亡的主要原因，例如肌萎缩性侧索硬化症（ALS）和脊髓损伤。尽管角色至关重要，但分子 PMC神经元身份的决定因素在很大程度上是未知的。我们发现PMC神经元的发展需要HOX5转录因子的持续活动。 MN中缺少HOX5基因的小鼠死于呼吸道出生时的失败和在PMC身份的多个方面表现出缺陷，包括细胞体位置，轴突指导和隔膜神经。在此提案中，我们将研究HOX5基因在确定和维持PHRENIC MN身份。在AIM 1中，我们将确定hox5蛋白在Phrenic Mns中的时间不同的功能以及phrenic Mn 整个生命周期都保持身份。在AIM 2中，我们将定义HOX5基因如何控制转录级别的Phrenic MN规范。在AIM 3中，我们将确定直接的HOX5效应子并剖析其调节机制。我们已经开发了一种综合方法，包括遗传模型，高通量测序，电生理学和行为分析（例如庞大的描绘）在体内解决这些问题。这该提案的总体目标是揭示Phrenif MN规范的基本原则和维护，以便我们可以开始考虑用于呼吸障碍的替代治疗方法。