Developmental gene networks of 5HT neurons in addiction, aggression, and anxiety

成瘾、攻击性和焦虑中 5HT 神经元的发育基因网络

• 批准号: 8836993
• 负责人: Susan M. Dymecki
• 金额: $ 59.27万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-04-15 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8836993
• 关键词: Action Potentials; Adolescence; Adult; Adverse effects; Affect; Affective; Age; Aggressive behavior; Alleles; Anxiety; Axon; Behavior; Behavioral; Biological Assay; Brain; Brain region; Cells; Childhood; Cognitive; Development; Developmental Gene; Disease; Dopamine; Dopamine D1 Receptor; Dopamine D2 Receptor; Electrophysiology (science); Emotional; Functional disorder; Gene Expression Profile; Genes; Genetic; Genetic Predisposition to Disease; Goals; Grant; Health; Human; Impulsivity; Individual; Ion Channel; Label; Link; Longevity; Maps; Methods; Molecular; Molecular Profiling; Mood Disorders; Motivation; Mus; Nervous System Physiology; Neurobiology; Neurons; Pathway interactions; Pattern; Pharmacogenetics; Phenotype; Presynaptic Terminals; Property; Prosencephalon; RNA; Research; Resolution; Rewards; Sensorimotor functions; Serotonergic System; Serotonin; Shapes; Slice; Social Behavior; Social Interaction; Sorting - Cell Movement; Stress; Substance abuse problem; Synapses; System; Techniques; Testing; Therapeutic; Tracer; Transgenes; Ursidae Family; Viral; Whole-Cell Recordings; Work; addiction; age related; base; behavior test; brain cell; cell type; critical period; differential expression; emotional behavior; improved; in vivo; innovation; male; motivated behavior; nerve supply; neural circuit; neurochemistry; neuronal cell body; new technology; novel; postsynaptic; postsynaptic neurons; receptor; receptor expression; response; social; therapeutic target; tool; transcription factor; transcriptome sequencing

DESCRIPTION (provided by applicant): The proposed research brings cutting-edge genetic tools to bear on understanding the neural circuitry under- lying aggression and motivated behavior. Our recent progress reveals that these behaviors in mice are regulated by two molecularly distinct, small subsets of brain serotonergic (5-HT) neurons: one subset, ~3,000 neurons, uniquely defined among 5-HT neurons by expression of the D1 dopamine (DA) receptor (Drd1a gene), and the other, ~1,000 neurons, by the D2 DA receptor (Drd2 gene). These results combined with the enabling genetic tools, like a powerfully sharpened wedge, can now be used to "break open" and access the circuitry, cellular properties, and molecular pathways underlying these consequential behaviors. Here we propose applying this "wedge" in the form of four aims to answer: What cellular and molecular properties are unique to these behavior-critical 5-HT neurons? As suggested by receptor expression, are these 5-HT neurons responsive to DA - a neurochemical commonly associated with the reward system of the brain? Through what forebrain circuitry do these subtypes modulate aggression and motivation? Do these parameters change across the life span, perhaps bearing on human age-related propensity for impulsivity, aggression, and substance abuse? In Aim 1, we will identify functional properties of the Drd1a and Drd2 5-HT neuron subtypes by transcriptional profiling (RNA-seq) and electrophysiological recording. This work is enabled through novel genetic tools for neuron subtype-specific marking, suitable for neuron subtype sorting and molecular profiling, and for whole-cell recording. These same genetic tools not only offer access to the soma of a 5-HT neuron subtype, but also to axons and terminals, thus allowing precise identification of target brain regions under neuron-subtype control - the goal of Aim 2. Functional postsynaptic connections will also be explored, with our intersectional genetic marking tools conferring unprecedented resolution to classic tract- tracing techniques as well as to cutting-edge viral approaches that involve trans-synaptic tracers. Thus, Aim 2 will define, label, and allow for molecular characterization of "aggression-relevant" postsynaptic neurons downstream in these circuits. In Aim 3, we will explore more deeply the behavioral facets modulated by these two 5-HT neuron subtypes and if their contributions vary across life span. Similar subtype-specific silencing methods will be employed as in the foundational aggression studies, but now additional social behaviors and neurological functions will be queried. In Aim 4, we will use pharmacogenetics (DREADDs) to transiently silence each Drd 5-HT neuron subtype during "childhood," asking if lasting changes occur that predispose to hyperaggression and altered social motivation in adulthood, as predicted by human studies that associate genetic predisposition via the 5-HT system, childhood stress, and adult pathological aggression. Our approaches are technically and conceptually innovative, and are foundational for discovering new, potentially behavior-selective, age-suitable therapeutics. Results compel a redefinition of 5-HT system organization.

描述（由申请人提供）：拟议的研究带来了尖端的遗传工具，以了解神经回路下的侵略和动机行为。我们最近的进展表明，小鼠的这些行为是由两个分子上不同的，脑多巴胺能（5-HT）神经元的小子集调节的：一个子集，约3,000个神经元，通过表达D1多巴胺（DA）受体（Drd 1a基因）在5-HT神经元中唯一定义，另一个子集，约1,000个神经元，通过D2 DA受体（Drd 2基因）。这些结果与使能的遗传工具相结合，就像一个有力的削尖的楔子，现在可以用来“打开”和访问这些后果行为背后的电路，细胞特性和分子途径。在这里，我们建议应用这个“楔子”的形式，四个目标来回答：什么样的细胞和分子特性是独特的，这些行为的关键5-HT神经元？正如受体表达所表明的那样，这些5-HT神经元对DA --一种通常与大脑奖励系统相关的神经化学物质--有反应吗？这些亚型通过什么样的前脑回路来调节攻击性和动机？这些参数是否会随着人的一生而改变，也许会影响到与年龄相关的冲动、攻击和药物滥用倾向？在目标1中，我们将通过转录谱（RNA-seq）和电生理记录来鉴定Drd 1a和Drd 2 5-HT神经元亚型的功能特性。这项工作是通过新的遗传工具，神经元亚型特异性标记，适合神经元亚型分选和分子分析，并为全细胞记录。这些相同的遗传工具不仅提供了对5-HT神经元亚型的索马的访问，而且还提供了对轴突和终末的访问，从而允许精确识别受神经元亚型控制的目标大脑区域-目标2的目标。功能性突触后连接也将被探索，与我们的交叉遗传标记工具赋予前所未有的决议，经典的道跟踪技术，以及尖端的病毒方法，涉及跨突触示踪剂。因此，目标2将定义，标签，并允许在这些电路下游的“侵略相关”突触后神经元的分子表征。在目标3中，我们将更深入地探索这两种5-HT神经元亚型调节的行为方面，以及它们的贡献是否随寿命而变化。类似的亚型特异性沉默方法将在基础攻击研究中使用，但现在将询问其他社会行为和神经功能。在目标4中，我们将使用药物遗传学（DREADDs）短暂沉默每个Drd 5-HT神经元亚型在“童年”，询问是否发生持久的变化，易患过度攻击和改变成年后的社会动机，如人类研究所预测的那样，通过5-HT系统，童年压力和成人病理性攻击将遗传易感性联系起来。我们的方法在技术上和概念上都是创新的，是发现新的、潜在的行为选择性的、适合年龄的治疗方法的基础。结果迫使5-HT系统组织的重新定义。