Mechanisms of Enteric Neuron Diversification

肠神经元多样化的机制

• 批准号: 10299010
• 负责人: E Michelle SOUTHARD-SMITH
• 金额: $ 48.89万
• 依托单位: VANDERBILT UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-16 至 2024-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10299010
• 关键词: Achalasia; Address; Affect; Alleles; Animals; Biological Assay; Blood flow; CCRL2 gene; Cell Line; Cells; Chick; Chromatin; Chronic; Complement; Congenital Megacolon; Constipation; Data; Defect; Development; Disease; Disease model; Distal; Embryo; Enteral; Enteric Nervous System; Epitopes; Essential Genes; Event; Excision; Ganglia; Gastrointestinal Diseases; Gastrointestinal Motility; Gastroparesis; Gene Expression; Genes; Genetic Transcription; Health; In Situ; Individual; Intestinal Diseases; Intestinal Motility; Intestines; Knowledge; Lead; Life; Liquid substance; Mediating; Megacolon; Motion; Mus; Mutant Strains Mice; Mutation; Neural Crest; Neuroglia; Neuronal Differentiation; Neurons; Patients; Phase; Play; Population; Protein Isoforms; Proteins; Reaction; Regulation; Regulatory Element; Role; Signal Pathway; Small Interfering RNA; Sorting - Cell Movement; Testing; Transposase; United States; Validation; Western Blotting; Work; antibody detection; base; cell motility; chromatin remodeling; cohesion; comparative; design; experimental study; fetal; lentivirally transduced; liquid chromatography mass spectrometry; migration; motility disorder; mouse model; mutant; nerve stem cell; nervous system development; neurogenesis; neuron development; novel therapeutics; nutrient absorption; progenitor; regenerative; relating to nervous system; single-cell RNA sequencing; tool; transcription factor; transcriptomics

Normal gastrointestinal (GI) motility is an essential prerequisite for nutrient absorption, fecal elimination and overall health. Nearly a quarter of the United States population is affected by intestinal disorders that lead to abnormal GI motility, chronic constipation and other functional bowel disorders. Greater understanding of the mechanisms that regulate differentiation of enteric neural progenitors (ENPs), which form the neurons and glia of the enteric nervous system (ENS), are needed to understand how the normal complement of functional enteric neurons within the intestine is generated. Sox10 is an essential transcription factor that functions in the neural crest derived progenitors that generate the ENS. Defects in Sox10 in patients and mice cause aganglionosis of the distal intestine leading to megacolon. Recent studies of Sox10 mutant mice have identified pronounced alterations of the ratios of different enteric neuron types in proximal innervated bowel of these animals that are accompanied by abnormal intestinal transit and motility. Although Sox10 is expressed in ENPs, these deficiencies among enteric neurons were unexpected because Sox10 is extinguished as neurons begin to differentiate, although its expression is sustained in enteric glia. The results suggest that Sox10 has greater roles in ENS development than simply promoting migration of ENPs during initial phases when the fetal gut is first colonized by progenitors. In the proposed analysis we will test the overarching hypothesis that Sox10 action in ENPs orchestrates transcriptional networks and chromatin accessibility setting in motion a regulatory cascade that orchestrates diversity of enteric neuron subtypes. In Aim 1 we will test the hypothesis that the mutant alleles of Sox10 alter enteric neuron ratios by disrupting transcriptional hierarchies in ENPs using single cell RNA sequencing (scRNASeq). In Aim 2 we will examine the hypothesis that Sox10 mutants disrupt chromatin accessibility in developing ENS lineages. Integration of information from these studies and validation of interacting gene effects in neural crest cultures will distinguish between potential developmental mechanisms that generate the normal repertoire of enteric neuron subtypes and will facilitate efforts to direct differentiation of enteric neurons for treatment of GI disease.

正常的胃肠道（GI）运动是营养吸收、粪便排泄和整体健康的必要前提。近四分之一的美国人口受到肠道疾病的影响，这些疾病会导致胃肠动力异常、慢性便秘和其他功能性肠道疾病。肠神经祖细胞（ENPs），形成肠神经系统（ENS）的神经元和神经胶质细胞的分化调节机制的更深入的理解，需要了解如何在肠道内的功能性肠神经元的正常补充产生。Sox 10是一种重要的转录因子，在神经嵴衍生的祖细胞中发挥作用，这些祖细胞产生ENS。患者和小鼠中Sox 10的缺陷引起远端肠的无神经节细胞症，导致巨结肠。最近对Sox10突变小鼠的研究发现，这些动物的近端神经支配肠中不同肠神经元类型的比例发生了明显的变化，并伴有异常的肠传输和运动。尽管Sox 10在ENPs中表达，但肠神经元中的这些缺陷是出乎意料的，因为Sox 10随着神经元开始分化而消失，尽管其表达在肠神经胶质中持续。结果表明，Sox 10在ENS发育中的作用比在胎儿肠道首次被祖细胞定植的初始阶段简单地促进ENP迁移更大。在拟议的分析中，我们将测试的总体假设，即Sox10的行动在ENPs编排转录网络和染色质可及性设置在运动的监管级联，编排多样性的肠神经元亚型。在目标1中，我们将使用单细胞RNA测序（scRNASeq）测试Sox 10的突变等位基因通过破坏ENPs中的转录层次来改变肠神经元比率的假设。在目标2中，我们将研究Sox10突变体在发育ENS谱系中破坏染色质可及性的假设。整合这些研究的信息和验证神经嵴培养物中相互作用的基因效应，将区分产生肠神经元亚型正常库的潜在发育机制，并将促进直接分化肠神经元治疗GI疾病的努力。