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: 8628623
• 负责人: Susan M. Dymecki
• 金额: $ 63.76万
• 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/8628623
• 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; 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; improved; in vivo; innovation; male; motivated behavior; nerve supply; neural circuit; neurochemistry; neuronal cell body; new technology; novel; postsynaptic; public health relevance; receptor; receptor expression; response; social; therapeutic target; tool; transcription factor; transcriptome sequencing

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 regu- lated 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 neu- rons 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 parame- ters change across the life span, perhaps bearing on human age-related propensity for impulsivity, aggres- sion, and substance abuse? In Aim 1, we will identify functional properties of the Drd1a and Drd2 5-HT neu- ron 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 mo- lecular 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 re- gions under neuron-subtype control - the goal of Aim 2. Functional postsynaptic connections will also be ex- plored, 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 si- lence 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 ap- proaches 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.

这项拟议的研究将尖端的基因工具应用于理解神经电路-- 说谎、攻击性和动机行为。我们的最新进展表明，小鼠的这些行为是有规律的。 由两个分子上不同的脑5-羟色胺(5-HT)能神经元的小亚群：一个亚群，~3,000 神经元，在5-羟色胺(5-HT)神经元中由D1多巴胺(DA)受体(Drd1a)的表达唯一定义 D2DA受体(Drd2基因)，以及其他约1,000个神经元。这些结果与 启用遗传工具，如强力磨尖的楔子，现在可以用来“打开”并接触到 这些结果行为背后的电路、细胞属性和分子途径。在这里我们 建议以四个目标的形式来应用这个“楔子”来回答：什么是细胞和分子特性 这些行为关键的5-羟色胺神经元是独一无二的？根据受体的表达，这些5-羟色胺是不是神经- 对DA--一种通常与大脑奖赏系统相关的神经化学物质--有反应的RON？ 这些亚型通过什么前脑回路调节攻击性和动机？做这些帕拉米- 人在一生中都会发生变化，可能会影响到人类与年龄相关的冲动倾向，攻击- 锡安，还有药物滥用？在目标1中，我们将确定Drd1a和Drd2 5-HTNeu-2的功能特性。 转录谱(RNA-seq)和电生理记录的RON亚型。此工作已启用 通过新的遗传工具进行神经元亚型特异性标记，适用于神经元亚型的分类和分子标记。 小叶剖面图，用于全细胞记录。这些相同的基因工具不仅提供了进入一个 5-羟色胺神经元亚型，也包括轴突和终末，从而可以精确识别靶脑重新定位。 神经元亚型控制下的神经元-目标2的目标。功能性突触后连接也将被排除在 利用我们的交叉遗传标记工具，对经典区域进行了前所未有的分辨率- 追踪技术以及涉及跨突触示踪剂的尖端病毒方法。因此，目标2 将定义、标记“攻击相关”突触后神经元，并允许对其进行分子表征 在这些环路的下游。在目标3中，我们将更深入地探讨受这些因素影响的行为方面 两种5-羟色胺神经元亚型，以及它们的贡献是否在一生中有所不同。类似的亚型特定沉默 方法将在基础攻击性研究中使用，但现在增加了社会行为和 神经功能将受到质疑。在目标4中，我们将使用药物遗传学(DREADD)来瞬间抑制 观察每个DRD5-羟色胺神经元亚型在“童年”期间的情况，询问是否发生了易患高血压的持久变化。 如人类研究预测的那样，成年后过度攻击性和改变的社会动机 通过5-羟色胺系统的遗传易感性、童年压力和成人病理性攻击。我们的AP- 专家在技术和概念上都是创新的，是发现新的、潜在的 行为选择疗法，适合年龄的疗法。结果迫使对5-羟色胺系统组织进行重新定义。