Pathway-specific Fyn signaling in the striatum and ethanol drinking

纹状体和乙醇饮用中的通路特异性 Fyn 信号传导

• 批准号: 8930906
• 负责人: DORIT RON
• 金额: $ 34.59万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-25 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8930906
• 关键词: AMPA Receptors; Address; Agonist; Alcohol abuse; Alcohol consumption; Behavior; Behavioral; Binding; Brain region; Corpus striatum structure; Coupled; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; DRD2 gene; Data; Designer Drugs; Development; Disease; Dopamine; Dopamine D1 Receptor; Dopamine D2 Receptor; Ethanol; Event; Exhibits; Extramural Activities; Fluorescence; GTP-Binding Proteins; Gene Delivery; Genes; Genetic; Genetically Engineered Mouse; Goals; Health; Laboratories; Light; Maintenance; Mediating; Methodology; Methods; Modeling; Molecular; Mus; N-Methyl-D-Aspartate Receptors; Neurons; Neurosciences; Outcome; Pathway interactions; Pharmaceutical Preparations; Phosphotransferases; Physiological; Physiological Adaptation; Play; Proto-Oncogene Proteins c-fyn; Resolution; Rewards; Rodent; Role; Self Administration; Signal Pathway; Signal Transduction; Synapses; Synaptic Membranes; System; Techniques; Testing; Transgenic Mice; United States National Institutes of Health; Viral; addiction; alcohol response; alcohol seeking behavior; base; cell type; drinking; drinking behavior; genetic approach; in vivo; innovation; learned behavior; motivated behavior; neuroadaptation; novel; receptor; recombinase; tool

DESCRIPTION (provided by applicant): This proposal is aimed at studying signaling-dependent neuroadaptations that occur in response to ethanol in subpopulations of neurons within the dorsomedial striatum (DMS). The DMS plays a central role in goal- directed behaviors and addiction, and we found that voluntary and passive exposure of rodents to ethanol activates the tyrosine kinase Fyn specifically in the DMS. We further discovered that in response to ethanol, activated Fyn phosphorylates the NR2B subunit of the NMDARs (GluN2B) resulting in increased synaptic activity of NMDA and AMPA receptors (NMDAR/AMPAR). Finally, we showed that the Fyn-signaling pathway in the DMS plays a crucial role in mechanisms underlying ethanol-drinking behaviors. Neurons in the DMS express either dopamine (DA) D1 or D2 receptors (D1R, D2R) that form the direct "Go" and indirect "No-Go" pathways. Thus, DA is thought to have different and possibly opposite effects on D1R and D2R neurons. D1Rs are coupled to G protein �s (Gs), which activates cAMP/PKA signaling, whereas D2Rs are coupled to Gi, which inhibits cAMP/PKA. We found that Fyn activation depends on cAMP/PKA, and that in vivo administration of a D1R agonist but not D2R agonist activates Fyn signaling in the DMS, and specifically in D1R DMS neurons. Together, these data suggest the DA activates a signaling pathway consisting of D1R/Gs/Fyn/GluN2B/AMPAR in D1R neurons. Ethanol increases DA levels in the striatum, and we hypothesize that ethanol activates Fyn signaling specifically in D1R neurons in the DMS to facilitate neuroadaptations in the direct "Go" pathway that drive ethanol drinking behaviors. We also hypothesize that remote activation of Gs signaling in D1R DMS neurons is sufficient to produce similar Fyn-dependent cellular and behavioral neuroadaptations. These hypotheses will be tested in vivo using transgenic mice that express Cre in D1R or D2R neurons, and will utilize innovative molecular and chemico- genetic approaches to manipulate single genes (Cre-FLEX), and to remotely activate Gs signaling using the Designer Receptors Exclusively Activated by Designer Drugs (DREADD) method in specific subpopulations of neurons. Aim 1 and Aim 2 will determine whether Fyn-dependent adaptations induced by ethanol occur in D1R, but not D2R, neurons in the DMS, and whether Gs DREADD activation in DMS D1R neurons is sufficient to produce similar outcomes. Aim 3 will investigate the contribution of Fyn signaling in D1R DMS neurons to ethanol drinking behaviors, and whether Gs DREADD activation of Fyn in D1R is sufficient to produce ethanol seeking and drinking. Combining Molecular and Systems Neuroscience methodologies, we will unravel cell- type specific signaling adaptations that underlie the development and maintenance of ethanol drinking and seeking behaviors.

描述（由申请人提供）：该提案旨在研究背内侧纹状体（DMS）内神经元亚群对乙醇的反应而发生的信号依赖神经适应。DMS 在目标导向行为和成瘾中发挥着核心作用。我们发现，啮齿类动物主动和被动接触乙醇会特别激活 DMS 中的酪氨酸激酶 Fyn。我们进一步发现，响应乙醇，会激活 Fyn。磷酸化 NMDAR 的 NR2B 亚基 (GluN2B)，导致 NMDA 和 AMPA 受体 (NMDAR/AMPAR) 的突触活性增加。 DMS 中的神经元表达多巴胺 (DA) D1 或 D2 受体（D1R、D2R），形成直接因此，DA 被认为对 D1R 和 D2R 神经元具有不同且可能相反的作用，D1R 与 G 蛋白 (Gs) 偶联，从而激活 cAMP/PKA 信号传导。 D2R 与 Gi 偶联，抑制 cAMP/PKA 我们发现 Fyn 激活依赖于 cAMP/PKA，并且体内施用 D1R 激动剂而非 D2R 激动剂会激活。 DMS 中的 Fyn 信号传导，特别是 D1R DMS 神经元中的信号传导，这些数据表明 DA 激活了 D1R 神经元中由 D1R/Gs/Fyn/GluN2B/AMPAR 组成的信号传导通路，而乙醇会增加纹状体中的 DA 水平。乙醇会特异性激活 DMS 中 D1R 神经元中的 Fyn 信号传导，以促进直接“Go”通路中的神经适应，从而驱动乙醇饮用行为。我们还捕获了这种远程激活。 D1R DMS 神经元中的 Gs 信号传导足以产生类似的 Fyn 依赖性细胞和行为神经适应。这些假设将使用在 D1R 或 D2R 神经元中表达 Cre 的转基因小鼠进行体内测试，并将利用创新的分子和化学遗传方法来实现。操纵单个基因 (Cre-FLEX)，并使用设计药物独家激活的设计受体 (DREADD) 方法在特定的神经元亚群中远程激活 Gs 信号传导。目标 2 将确定乙醇诱导的 Fyn 依赖性适应是否发生在 DMS 中的 D1R 神经元中，而不是 D2R 中，以及 DMS D1R 神经元中的 Gs DREADD 激活是否足以产生类似的结果。目标 3 将研究 Fyn 的贡献。结合分子和系统神经科学，D1R DMS 神经元中的信号传导至乙醇饮酒行为，以及 D1R 中 Fyn 的 Gs DREADD 激活是否足以产生乙醇寻找和饮酒。通过方法论，我们将揭示细胞类型特异性信号适应，这些适应是乙醇饮用和寻求行为的发展和维持的基础。