Cell type-based genomics of developmental plasticity in cortical GABA interneuron

基于细胞类型的皮质 GABA 中间神经元发育可塑性基因组学

• 批准号: 7642897
• 负责人: Z JOSH HUANG
• 金额: $ 25.2万
• 依托单位: COLD SPRING HARBOR LABORATORY
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-16 至 2011-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7642897
• 关键词: Autistic Disorder; Binding Proteins; Brain; Brain Diseases; Brain-Derived Neurotrophic Factor; Cell physiology; Co-Immunoprecipitations; Complex; Data; Development; Epitopes; FLAG peptide; Future; Gene Expression; Gene Expression Alteration; Gene Expression Profiling; Genes; Genetic; Genomics; Harvest; Heterogeneity; In Situ; Interneurons; Mediating; Messenger RNA; Methods; Microarray Analysis; Molecular; Molecular Profiling; Mus; Neocortex; Neurons; Neurosciences; Ocular Dominance; Physiological; Resistance; Rett Syndrome; Schizophrenia; System; Transgenic Organisms; Translating; area striata; base; brain tissue; cell type; critical period; dark rearing; developmental plasticity; experience; gamma-Aminobutyric Acid; insight; mouse model; neural circuit; novel; overexpression; public health relevance; research study; visual deprivation

DESCRIPTION (provided by applicant): GABA-mediated inhibition is crucial for the function and plasticity of neural circuits in neocortex, but the cellular diversity of the GABAergic system has been resistant to conventional anatomical, physiological, and genomic approaches. For example, maturation of inhibitory circuitry in primary visual cortex (V1) promotes the development of ocular dominance (OD) plasticity and its critical period, but the cellular and molecular mechanisms underlying the developmental and experience-dependent maturation of GABA interneurons remain poorly understood. Analysis of gene expression profiles should provide fundamental insights into this issue, but the heterogeneity of GABA interneurons has precluded such studies. Here we propose a genetic strategy to implement a novel method for cell type-based analysis of gene expression in GABAergic system and in complex brain tissues in general. Using Cre/loxP-regulated gene expression strategy, we will generate knockin mice expressing an epitope (FLAG)-tagged polyA binding protein (PABP) in different classes of interneurons. Actively translated mRNAs from interneurons in V1 will be harvested by co-immunoprecipitation against the FLAG peptide and subjected to microarray analysis. Three major classes of interneurons will be analyzed during the critical period of OD plasticity. Since the critical period can be either accelerated or delayed by BDNF (brain-derived neurotrophic factor) overexpression or dark-rearing (DR), respectively, the same cell types will be analyzed in BDNF transgenic and dark-reared mice. We aim to identify genes in specific cell types whose expression 1) correlate with the progression of critical period, 2) are regulated by BDNF and DR in a manner that corresponds to alterations in critical period. These studies will provide a comprehensive picture of transcriptomes in defined GABAergic cell types during the critical period, unravel the molecular mechanisms which direct experience-dependent maturation of inhibitory interneurons, and guide future experiments to examine specific cellular processes. Because cell types are functional units of neural circuits, this approach will 1) substantially increase the sensitivity for detecting alterations of gene expression in complex brain tissues, 2) allow meaningful interpretation of gene expression data in the context of neural circuit development and function, 3) greatly enhance the power of gene expression analysis in system neuroscience and in mouse model of brain disorders. PUBLIC HEALTH RELEVANCE: Here we proposed to establish a cell type-based genetic strategy to study gene expression profiles in mouse brain. This method will greatly enhance the sensitivity and explanatory power of genomic studies of mouse model of brain disorders, such as Rett Syndrome, schizophrenia, and autism.

描述（由申请人提供）：GABA介导的抑制对于新皮层中神经回路的功能和可塑性至关重要，但GABA能系统的细胞多样性对常规解剖学、生理学和基因组方法具有抗性。例如，初级视皮层（V1）抑制回路的成熟促进了眼优势（OD）可塑性及其关键期的发育，但GABA中间神经元发育和经验依赖性成熟的细胞和分子机制仍知之甚少。基因表达谱的分析应该提供基本的见解，这个问题，但GABA中间神经元的异质性排除了这样的研究。在这里，我们提出了一种遗传策略，以实现一种新的方法，在GABA能系统和复杂的脑组织中的基因表达的细胞类型为基础的分析。使用Cre/loxP调控的基因表达策略，我们将产生在不同类别的中间神经元中表达表位（FLAG）标记的polyA结合蛋白（PABP）的敲入小鼠。通过针对FLAG肽的免疫共沉淀收获来自V1中中间神经元的主动翻译的mRNA，并进行微阵列分析。三个主要类别的中间神经元将在OD可塑性的关键时期进行分析。由于BDNF（脑源性神经营养因子）过表达或暗饲养（DR）可分别加速或延迟关键期，因此将在BDNF转基因小鼠和暗饲养小鼠中分析相同的细胞类型。我们的目标是鉴定特定细胞类型中的基因，其表达1）与关键期的进展相关，2）由BDNF和DR以对应于关键期改变的方式调节。这些研究将提供一个全面的图片中定义的GABA能细胞类型在关键时期的转录组，解开的分子机制，直接的经验依赖性成熟的抑制性中间神经元，并指导未来的实验，以检查特定的细胞过程。由于细胞类型是神经回路的功能单位，因此该方法将1）显著增加检测复杂脑组织中基因表达改变的灵敏度，2）允许在神经回路发育和功能的背景下对基因表达数据进行有意义的解释，3）极大地增强系统神经科学和脑疾病小鼠模型中基因表达分析的能力。公共卫生相关性：在这里，我们建议建立一个基于细胞类型的遗传策略来研究小鼠大脑中的基因表达谱。这种方法将大大提高对Rett综合征、精神分裂症和自闭症等脑疾病小鼠模型的基因组研究的灵敏度和解释力。