IMPACT OF LOSS OF THE AUTISM RISK GENE CHD8 ON EXPRESSION, EPIGENETICS AND CELLULAR FUNCTIONING OF THE DOPAMINERGIC SYSTEM

自闭症风险基因 CHD8 缺失对多巴胺能系统表达、表观遗传学和细胞功能的影响

• 批准号: 10660565
• 负责人: Rebecca Ann Muhle
• 金额: $ 69.33万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-04-17 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660565
• 关键词: Affect; Animal Model; Atlases; Attenuated; Basal Ganglia; Behavior; Behavioral; Binding; Biological; Biological Assay; Biology; Biotinylation; Brain; Brain Diseases; Cell physiology; Cells; Cellular biology; ChIP-seq; Child; Chromatin; Chronic; Collaborations; Complex; Corpus striatum structure; Cre driver; Critical Pathways; DNA; DNA Sequence Alteration; DNA-Binding Proteins; Data; Data Set; Defect; Development; Doctor of Medicine; Doctor of Philosophy; Dopamine; Dopamine Agonists; Dopamine Receptor; Electrophysiology (science); Epigenetic Process; Fellowship; Female; Fiber; Foundations; Funding; Future; Gene Expression; Genes; Genetic Risk; Genetic Transcription; Genomic Segment; Genomics; Goals; Human; Investigation; Knowledge; Label; Lifestyle-related condition; LoxP-flanked allele; Maps; Mentorship; Microdialysis; Midbrain structure; Modeling; Molecular; Molecular Abnormality; Molecular Genetics; Morbidity - disease rate; Mus; Mutation; National Institute of Mental Health; Neurobiology; Neurodevelopmental Disorder; Neurons; Nuclear; Nuclear RNA; Outcome; Pathway interactions; Pharmaceutical Preparations; Photometry; Play; Population; Psychiatrist; Public Health; Regulation; Research; Research Personnel; Resolution; Risk; Risk Factors; Role; Societies; Specific qualifier value; Stimulus; Structure; Symptoms; Synapses; System; Transgenes; Transposase; Universities; autism spectrum disorder; behavioral impairment; cell type; chromatin immunoprecipitation; chromatin remodeling; dopamine system; dopamine transporter; dopaminergic neuron; epigenetic profiling; extracellular; functional genomics; helicase; in vivo; insight; male; mortality; mouse model; multiple omics; neurobehavioral disorder; neurotransmission; novel; novel therapeutics; optogenetics; postsynaptic; presynaptic; promoter; repetitive behavior; response; risk variant; sex; social; stereotypy; tool; trait; transcriptome sequencing; transcriptomic profiling; transcriptomics; translational study; transmission process

PROJECT SUMMARY Dr. Rebecca Muhle is a practicing child psychiatrist and an Early Stage Investigator with a strong track record of developing molecular genetic tools to elucidate the mechanism of neurodevelopmental disorders. Her long- term goal is to identify cell types, circuits and regulatory networks affected by loss of Chromodomain Helicase DNA-binding Protein 8 (CHD8), a high confidence autism spectrum disorder (ASD) risk gene. Dr. Muhle initiated her studies of CHD8 during her fellowship with James Noonan, Ph.D. with co-mentorship by Matthew State, M.D., Ph.D. She successfully obtained research funding from the National Institute for Mental Health and the Simons Foundation for Autism Research to determine the impact of CHD8 and its loss on regulatory networks of the developing cortex, and she showed that CHD8 in developing cortex regulates other ASD risk genes. She is extending this research at Columbia University in collaboration with Jeremy Veenstra-VanderWeele, M.D. and Muhammed Osman Chohan, M.D., experts in translational animal models of neurobehavioral disorders and the study of monoaminergic neurotransmission. Together, they have found reduced stereotypy and attenuated hyperlocomotor activity in male, but not female Chd8+/- mice after inhibition of the dopamine transporter, with an intact response to dopamine receptor agonism, suggesting that CHD8 plays a critical role in the development of the dopaminergic circuit between the midbrain and striatum. The overall objective of this R01 proposal is to elucidate the mechanisms whereby CHD8 genetic mutations affect cells and pathways critical for core symptoms of ASD and other neurodevelopmental disorders, by integrating state-of-the-art single nuclear transcriptomics and cell type specific functional genomics with electrophysiologic and behavioral probing of animal models with a loss of CHD8 expression. The following three independent specific aims will address the central hypothesis that CHD8 regulates genes that are critical for the function of the basal ganglia and dopaminergic system, and that loss of CHD8 will dysregulate these genes and other ASD risk genes. This project will 1) identify the cellular, transcriptional, and epigenetic changes in the developing Chd8+/- mouse ventral midbrain and striatum using single nuclear RNA sequencing (snRNAseq) and chromatin accessibility (snATACseq), 2) elucidate how CHD8 loss causes a defect in the molecular transmission of the DA stimulus in the basal ganglia using fiber photometry and in vivo extracellular recordings using constitutive and conditional CHD8 haploinsufficiency mouse models, and 3) localize CHD8 binding activity in specific cell types of the dopaminergic system using chromatin immunoprecipitation and sequencing of a conditionally biotinylated Chd8-tag transgene. By studying CHD8, a key regulatory molecule that targets other ASD risk genes, Dr. Muhle will close a critical knowledge gap in the role of CHD8 in the circuitry implicated in ASD-related behaviors.

项目概要 Rebecca Muhle 博士是一位执业儿童精神病学家和早期研究人员，拥有良好的记录 开发分子遗传工具来阐明神经发育障碍的机制。她的长—— 术语目标是确定受染色质结构域解旋酶损失影响的细胞类型、电路和调控网络 DNA 结合蛋白 8 (CHD8)，一种高可信度自闭症谱系障碍 (ASD) 风险基因。 Muhle 博士发起 她在与 James Noonan 博士一起研究 CHD8 期间。在马修州立的共同指导下， 医学博士、博士她成功获得了国家心理健康研究所和美国国家心理健康研究所的研究经费。 西蒙斯自闭症研究基金会将确定 CHD8 及其缺失对监管网络的影响 她发现发育中皮层中的 CHD8 调节其他自闭症谱系障碍 (ASD) 风险基因。 她正在哥伦比亚大学与 Jeremy Veenstra-VanderWeele 合作扩展这项研究， 医学博士和穆罕默德·奥斯曼·乔汉医学博士，神经行为障碍转化动物模型专家 以及单胺能神经传递的研究。他们共同发现，刻板印象减少了， 抑制多巴胺后，雄性 Chd8+/- 小鼠的过度运动活性减弱，但雌性 Chd8+/- 小鼠的运动活性没有减弱 转运蛋白，对多巴胺受体激动具有完整的反应，表明 CHD8 在 中脑和纹状体之间多巴胺能回路的发育。 R01的总体目标 提案旨在阐明 CHD8 基因突变影响细胞和通路的机制 通过整合最先进的单核技术，治疗自闭症谱系障碍（ASD）和其他神经发育障碍的核心症状 转录组学和细胞类型特异性功能基因组学以及电生理学和行为学探测 CHD8表达缺失的动物模型。 以下三个独立的具体目标将解决 CHD8 调节基因的中心假设 对于基底神经节和多巴胺能系统的功能至关重要，CHD8 的缺失将 失调这些基因和其他 ASD 风险基因。该项目将 1) 识别细胞、转录和 使用单核 RNA 观察发育中的 Chd8+/- 小鼠腹侧中脑和纹状体的表观遗传变化 测序 (snRNAseq) 和染色质可及性 (snATACseq)，2) 阐明 CHD8 缺失如何导致缺陷 使用纤维光度测定法和体内 DA 刺激在基底神经节中的分子传递 使用组成型和条件性 CHD8 单倍体不足小鼠模型进行细胞外记录，以及 3) 使用染色质定位多巴胺能系统特定细胞类型中的 CHD8 结合活性 条件性生物素化 Chd8 标签转基因的免疫沉淀和测序。通过研究 CHD8， Muhle 博士将填补针对其他 ASD 风险基因的关键调控分子的关键知识空白 CHD8 在与 ASD 相关行为有关的电路中的作用。