Inhibitory cell types and circuits in the lateral hypothalamus

项目摘要/摘要 这项提议的目标是在电路水平上理解外侧的GABA能神经元。 下丘脑区(LHA)通过解析其分子和功能多样性以及局部和远程 连通性。LHA是协调行为的基本方面的关键，包括唤醒， 压力、进食和积极的行为。由于它位于多个神经和神经的交叉点上 体液系统，LHA驱动维持生理动态平衡的基本行为程序 和行为。LHA的不同功能背后是一个异常不同的人口群体 神经细胞类型，其中很少被识别。LHA(LHAGABA)内的抑制性GABA能神经元 成为进食、奖励和压力的有力驱动者。然而，在这一大类神经元中，存在着糟糕的问题 已解决但在功能上重要的亚群，这可能不同地决定行为输出。 传统方法在破译LHAGABA的分子和功能多样性方面能力有限 神经元，这是我们理解LHA回路在健康和疾病中所起作用的主要障碍。 因此，迫切需要系统地描述神经化学特性、细胞特性和 LHAGABA神经元功能亚群的连通性是电路水平行为的先决条件 分析。为了填补这一知识空白，我们将建立第一个大规模和系统的分子、细胞和 LHAGABA神经元在单细胞分辨率下的连通性分析 电生理表型、基于光遗传学的电路图谱和单细胞转录图谱。 我们的中心假设是LHAGABA神经元可以根据以下因素分为不同的功能亚型 关键分子标记、电信号和突触连接模式。我们将探讨这一假设 有三个具体目标。目标1将系统地定义电生理和神经调节表型 候选LHAGABA神经元群体，并根据长期预测提炼这些特征以 蓝斑(LC)。目标2将确定LHAGABA神经元群体之间的突触连接性 以及关键的唤醒相关靶点，在LHA和LC内，使用膜片钳电生理学和 光遗传学。Aim 3将使用尖端的定量单细胞转录图谱方法来解密 新的、分子上不同的LHAGABA神经元群体。影响：作为第一个综合性神经化学物质， 电生理和解剖学普查LHA中的抑制细胞类型，该项目将产生功能 LHAGABA神经元的亚群，反过来将允许识别新的设计的关键标记 Cre驱动器线和交叉遗传工具，用于对LHAGABA电路的行为进行特定的电路剖析。 此外，对LHAGABA细胞类型和电路的深入了解有望识别 神经精神疾病、成瘾、创伤后应激障碍、睡眠和代谢的治疗目标 精神错乱。

PROJECT SUMMARY/ABSTRACT The goal of this proposal is to develop a circuit-level understanding of GABAergic neurons in the lateral hypothalamic area (LHA) by resolving their molecular and functional diversity and local and long-range connectivity. The LHA is a linchpin in the orchestration of fundamental aspects of behavior including arousal, stress, feeding and motivated behavior. Owing to its unique position at the intersection of multiple neural and humoral systems, the LHA drives essential behavioral programs that maintain homeostatic balance in physiology and behavior. Underlying the diverse functions of the LHA is an exceptionally heterogeneous population of neuronal cell types, of which few have been identified. Inhibitory GABAergic neurons in the LHA (LHAGABA) have emerged as potent actuators of feeding, reward and stress. However, within this broad class of neurons lie poorly resolved but functionally important subpopulations, which may differentially determine behavioral output. Conventional methods are limited in their ability to decipher the molecular and functional diversity of LHAGABA neurons, which represents a major barrier in our understanding of the role of LHA circuits in health and disease. There is, therefore, a critical need to systematically delineate the neurochemical identity, cellular properties and connectivity of functional subpopulations of LHAGABA neurons as a prerequisite to circuit-level behavioral analyses. To fill this knowledge gap, we will establish the first large-scale and systematic molecular, cellular and connectivity analysis of LHAGABA neurons at single-cell resolution using an integrated approach of electrophysiological phenotyping, optogenetics-based circuit mapping and single-cell transcriptional profiling. Our central hypothesis is that LHAGABA neurons can be classified into distinct functional subtypes according to key molecular markers, electrical signatures and patterns of synaptic connectivity. We will probe this hypothesis in three Specific Aims. Aim 1 will systematically define the electrophysiological and neuromodulatory phenotypes of candidate LHAGABA neuron populations and refine these characteristics based on long-range projections to the locus coeruleus (LC). Aim 2 will determine the synaptic connectivity between populations of LHAGABA neurons and key, arousal-related targets, both within the LHA and the LC, using patch-clamp electrophysiology and optogenetics. Aim 3 will apply cutting-edge quantitative single-cell transcriptional profiling methods to decipher novel, molecularly distinct populations of LHAGABA neurons. Impact: As the first comprehensive neurochemical, electrophysiological and anatomical census of inhibitory cell types in the LHA, this project will yield functional subpopulations of LHAGABA neurons that, in turn, will allow the identification of key markers for the design of novel cre driver lines and intersectional genetic tools for circuit-specific dissection of LHAGABA circuits in behavior. Furthermore, a deeper understanding of LHAGABA cell types and circuits holds the promise of identifying therapeutic targets for neuropsychiatric illnesses, addiction, post-traumatic stress disorder, sleep and metabolic disorders.