Mechanisms of Immediate Early Gene Regulation in Neurons

神经元立即早期基因调控机制

• 批准号: 8720090
• 负责人: Anandasankar Ray
• 金额: $ 18.81万
• 依托单位: UNIVERSITY OF CALIFORNIA RIVERSIDE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8720090
• 关键词: Address; Alzheimer' s Disease; Animal Model; Antibodies; Autistic Disorder; Binding Sites; Bioinformatics; Biological Assay; Brain; Cataloging; Catalogs; Cells; Cereals; Code; Cyclic AMP-Responsive DNA-Binding Protein; DNA Sequence; Drosophila genus; Drosophila melanogaster; Elements; Exposure to; Family; Fluorescence; Gene Cluster; Gene Expression; Gene Expression Regulation; Genes; Genetic; Genetic Transcription; Goals; Homologous Gene; Human; Immediate-Early Genes; In Situ; Kinetics; Label; Lead; Learning; Life; Link; Maps; Memory; Memory Loss; Modeling; Molecular; Molecular Analysis; Mutate; Nervous system structure; Neurodegenerative Disorders; Neurologic; Neuronal Plasticity; Neurons; Organism; Pattern; Play; Process; Protocols documentation; RNA; Regulation; Regulatory Pathway; Reporter; Reporter Genes; Reporting; Resources; Role; Sensory; Series; Site; Synaptic plasticity; System; TATA Box; Testing; Training; Transgenic Organisms; base; design; fly; gene induction; genetic analysis; genome-wide; insight; member; memory recall; memory retention; neural circuit; novel; post-traumatic stress; promoter; public health relevance; relating to nervous system; response; sensory stimulus; tool; transcription factor

DESCRIPTION (provided by applicant): The ability to acquire, store and recall memories is a defining feature of the brain that is conserved from humans to Drosophila. Immediate Early Genes (IEGs) are genes whose expression is stimulated by neuronal activity, and is often transient, a feature that makes them prime candidates for modifying neural plasticity. Yet very little is understood about the regulation and function of IEGs in any organism. Aberrations in neural plasticity, learning and memory can cause severe neurological conditions such as Alzheimer's, dementia, post-traumatic stress and autism, underscoring the need for elucidating molecular mechanisms that underlie memory. We have identified a suite of 288 IEGs in the Drosophila brain using RNASeq analysis after exposure to sensory stimuli of various durations (10, 20, 30, 45 mins), 65% of which have homologs in humans. Based on the kinetics of expression modulation the IEGs cluster into 5 groups suggesting differences in regulatory mechanisms. Using an unbiased bioinformatics approach we were able to identify over-represented DNA sequence motifs in the upstream regions of each cluster of IEGs. The motifs for cluster 1 and 2 are remarkably alike, and match the binding site of the GATA family of transcription factors. Genetic and molecular analysis showed that a GATA factor, grain, was indeed required for expression of IEGs. The goal of this proposal is to test the hypothesis that grain and other GATA factors play a role in activity-dependent modulation of IEG expression and therefore a central role in acquisition and retention of memory. The proposal is highly significant since this represents one of the first major IEG regulatory pathways since CREB and could present an opportunity to understand the link between neuronal activity, IEG expression and memory. In addition, the proposal will use IEG promoters to provide transgenic tools to map activated neural circuits in brains of live behaving flies. The approach for analysis of IEG regulation by GATA factors will be accomplished in two specific aims outlined here. (1) The first aim will validate the role of grain in IEG regulation, identify its genome-wide targets, map changes in its localization in the brain and investigate its role in memory. (2) The second aim will investigate the regulatory DNA sequences of the GATA- dependent IEGs to test for direct regulation. In addition it will develop transgenic flies where the IEG promoter will be used to encode a genetic fluorescent reporter that marks activated neurons. Successful completion of the proposed studies will uncover transcription factors and neuronal circuits underlying fundamental mechanisms of learning and memory and establish tools that will be widely useful for anatomical studies of neural circuits.

描述（由申请人提供）：获取，存储和回忆记忆的能力是大脑的定义特征，它是从人类到果蝇的保守的。直接的早期基因（IEG）是其表达受神经元活性刺激的基因，并且通常是短暂的，该特征使它们成为修改神经可塑性的主要候选者。然而，关于IEG在任何生物体中的调节和功能的理解很少。神经可塑性，学习和记忆的像差可能会导致严重的神经系统疾病，例如阿尔茨海默氏症，痴呆症，创伤后压力和自闭症，强调了阐明记忆构成的分子机制的需求。 在暴露于各种持续时间（10、20、30、45分钟）的感觉刺激之后，我们使用RNASEQ分析确定了果蝇大脑中288个IEG的套件，其中65％的人在人类中具有同源性。基于表达调制的动力学，IEG群集成5组，表明调节机制的差异。使用公正的生物信息学方法，我们能够在每个IEG群的上游区域中识别代表过多的DNA序列基序。群集1和2的基序非常相似，并且与转录因子的GATA家族的结合位点匹配。遗传和分子分析表明，IEG表达确实需要GATA因子，晶粒。 该提案的目的是检验以下假设：晶粒和其他GATA因素在IEG表达的活动依赖性调制中起作用，因此在获得和保留记忆中起着核心作用。该提案非常重要，因为这代表了自Creb以来的第一个主要IEG监管途径之一，并且可以提供一个机会来理解神经元活动，IEG表达和记忆之间的联系。 此外，该提案将使用IEG启动子提供转基因工具来绘制活蝇的大脑中激活的神经回路。 在此处概述的两个具体目的中，将通过GATA因素对IEG调节进行分析的方法。 （1）第一个目标将验证晶粒在IEG调节中的作用，确定其全基因组靶标，地图在大脑中的定位变化并研究其在记忆中的作用。 （2）第二个目标将研究依赖性IEG的调节性DNA序列，以测试直接调节。此外，它将开发转基因蝇，其中IEG启动子将用于编码标记激活神经元的遗传荧光报告基因。 成功完成拟议的研究将发现学习和记忆基本机制的基本机制的转录因子和神经元电路，并建立工具，这些工具将对神经回路的解剖学研究非常有用。