Structure and function of dopamine receptors

描述（由申请人提供）：儿茶酚胺多巴胺在认知、情绪和行为功能的调节中起主要作用，并且其调节的异常与许多精神和神经障碍有关。多巴胺通过D2样（D2，D3，D4）和D1样（D1，D5）受体发挥作用，这些受体是七跨膜片段G蛋白偶联受体（GPCR）超家族的成员。该项目的长期目标是：1）了解多巴胺受体和相关生物胺受体中激动剂和拮抗剂结合和特异性的结构基础; 2）确定激动剂结合如何转换为G蛋白激活。许多用于治疗精神疾病的药物，包括精神分裂症，注意力缺陷多动障碍（ADHD）和抑郁症，直接或间接地靶向多巴胺受体。我们提出以下具体目标：1。为了确定多巴胺D2受体（D2 R）的信号传导单元的功能化学计量，使用代表性的A家族GPCR。我们将确定是否两个受体信号通过一个单一的异源三聚体G蛋白，激活一个单一的信号单位D2 R所需的激动剂的数量，以及激动剂或拮抗剂的作用结合到第二个原聚体中的同源和异源信号单位。2.采用生物化学、生物物理学和光学方法，研究D2 R异源二聚化在原代培养和体内果蝇神经元中的特异性。3.利用基于共振能量转移的生物传感器研究D2 R同聚体和异聚体在G蛋白激活中的作用。为了完成我们的目标，我们将结合联合收割机的实验，结构和计算方法受体的结构和功能。除了在异源细胞中的工作，我们将使用小鼠核中多刺神经元的原代培养和果蝇作为模型系统，进一步解剖同源和异源受体信号在体内的重要性。此外，我们将使用我们新开发的基于能量转移的生物传感器将异聚体受体复合物与G蛋白活化在真实的时间内生物连接。7.公共卫生相关性：许多用于治疗精神疾病的药物，包括精神分裂症，注意力缺陷多动障碍（ADHD）和抑郁症，直接或间接地靶向多巴胺受体。多巴胺受体可能存在于与其他GPCR的同源和异源复合物中并发挥作用，这开辟了新的药理学可能性，如果基于对这种信号串扰的机制基础的清楚理解，则将最好地利用这种可能性。

DESCRIPTION (provided by applicant): The catecholamine dopamine plays a major role in the regulation of cognitive, emotional and behavioral functions, and abnormalities in its regulation have been implicated in a number of psychiatric and neurological disorders. Dopamine acts through D2-like (D2, D3, D4) and D1-like (D1, D5) receptors, which are members of the seven transmembrane segment G protein-coupled receptor (GPCR) superfamily. The long-term goals of this project are: 1) to understand the structural bases of agonist and antagonist binding and specificity in dopamine receptors and related biogenic amine receptors and 2) to determine how agonist binding is transduced into G protein activation. Many drugs used to treat psychiatric disorders, including schizophrenia, attention-deficit hyperactivity disorder (ADHD), and depression, target dopamine receptors, either directly or indirectly. We propose the following specific aims: 1. To determine the functional stoichiometry of the signaling unit of the dopamine D2 receptor (D2R), a representative Family A GPCR. We will determine whether two receptors signal through a single heterotrimeric G protein, the number of agonists required to activate a single signaling unit of D2R, and the role of agonist or antagonist binding to the second protomer in homomeric and heteromeric signaling units. 2. To determine the specificity of D2R heterodimerization in neurons in primary culture and in vivo in Drosophila melanogaster using biochemical, biophysical, and optical methods. 3. To differentiate the role of signaling of D2R homomers and heteromers using a novel resonance energy transfer based-biosensor for G protein activation. To complete our objectives we will combine experimental, structural, and computational approaches to receptor structure and function. In addition to work in heterologous cells, we will use mouse nucleus accumbens medium spiny neurons in primary culture and Drosophila melanogaster as a model system to dissect further the importance of homo- and heteromeric receptor signaling in vivo. Moreover, we will use our newly developed energy transfer based-biosensor to link biophysically the heteromeric receptor complex with G protein activation in real time. 7. PUBLICE HEALTH RELEVANCE: Many drugs used to treat psychiatric disorders, including schizophrenia, attention-deficit hyperactivity disorder (ADHD), and depression, target dopamine receptors, either directly or indirectly. That dopamine receptors may exist and function in homo- and heteromeric complexes with other GPCRs opens new pharmacological possibilities that will be best exploited if based on a clear understanding of the mechanistic basis of this signaling crosstalk.