DETERMINANTS OF DOPAMINE RECEPTOR FUNCTION

目的在于通过药物调节中皮质和纹状体黑质通路 抑制或增强多巴胺能神经传递是一种常用的 治疗许多精神和神经退行性疾病的策略。 这些药物通过多巴胺受体作用， 离子通道活性、蛋白激酶活性和基因的长期变化 表情最近发现的多个G蛋白连接的多巴胺 表现出经典的“D1”样或“D2-样”受体亚型 配体结合和信号转导特性提出了几个 关于每个受体所发挥的具体功能的问题。 目前至少有两个类似D1的DA和至少三个类似D2的DA 已知的受体我之前对几个D1- 和D2样亚型表明，每个受体蛋白具有独特的 细胞和亚细胞分布在中皮层，中脑边缘， 和黑质纹状体通路。这些结果支持了这样一种观点， subtype子类型serves服务a unique独特function功能.然而，亚型特异性信号 转导差异尚未在体内鉴定。没有 这个功能信息，很难理解， 多种D1样和D2样受体的生理需求 亚型我的研究目标是从分子和细胞上 差异调节DA受体功能的过程， 使用D1样受体作为范例的体内定位。一 实验方法包括使用酵母双杂交系统， 鉴定可能指定亚型特异性偶联的蛋白质， 信号转导系统或亚细胞定位。我的策略是 使用密切相关的hD 1和hD 5亚型中的独特序列 作为检测人脑中表达的相互作用蛋白质的诱饵。在 互补的方法，我将使用亚型特异性单克隆 抗体和亲和层析以分离相互作用的蛋白质。 亚型特异性抗体也将用于确认受体 与双杂交筛选中鉴定的蛋白质相互作用 免疫沉淀实验。这项研究将导致更好的 了解DA受体系统的分子组织， 并确定新的分子靶点来治疗精神疾病和运动 紊乱

Regulation of mesocortical and striatonigral pathways by drugs aimed at inhibiting or enhancing dopaminergic neurotransmission is a commonly used strategy for treating many psychiatric and neurodegenerative diseases. These drugs act through dopamine receptors to elicit both short and long term changes in ion channel activity, protein kinase activities, and gene expression. The recent discovery of multiple G-protein-linked dopamine receptor subtypes exhibiting either classical "D1"-like or "D2-like" ligand binding and signal transduction properties raises several questions regarding the specific functions served by each receptor. Currently there are at least two D1-like and at least three D2-like DA receptors known. My previous immunohistochemical analyses of several D1- and D2-like subtypes showed that each receptor protein has a unique cellular and subcellular distribution within mesocortical, mesolimbic, and nigrastriatal pathways. These results support the notion that each subtype serves a unique function. However, subtype-specific signal transduction differences have not yet been identified in vivo. Without this functional information, it is difficult to understand the physiologic requirements for multiple D1-like and D2-like receptor subtypes. The goal of my research is to identify molecular and cellular processes that differentially regulate DA receptor function and localization in vivo using the D1-like receptors as a paradigm. One experimental approach involves use of the yeast two-hybrid system to identify proteins that potentially specify subtype-specific coupling to signal transduction systems or subcellular localization. My strategy is to use unique sequences within the closely related hD1 and hD5 subtypes as bait for detecting interacting proteins expressed in human brain. In complementary approaches, I will use subtype-specific monoclonal antibodies and affinity chromatography to isolate interacting proteins. Subtype-specific antibodies will also be used to confirm receptor interaction with proteins identified in the two-hybrid screen through immunoprecipitation experiments. This research will lead to a better understanding of the molecular organization of the DA receptor system, and identify new molecular targets for treating psychiatric and movement disorders.