DOPAMINE-LINKED PHOSPHOINOSITIDE METABOLISM IN BRAIN

脑中多巴胺连接的磷酸肌醇代谢

• 批准号: 2839337
• 负责人: EITAN FRIEDMAN
• 金额: $ 19.65万
• 依托单位: MCP HAHNEMANN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-11-11 至 2000-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2839337
• 关键词: G protein; brain metabolism; complementary DNA; dopamine; dopamine receptor; drug metabolism; enzyme activity; in situ hybridization; isozymes; laboratory rat; lipid metabolism; molecular cloning; neuropharmacology; neurotransmitter metabolism; northern blottings; nucleic acid sequence; phosphatidylinositols; phospholipase C; phosphoproteins; protein structure function; receptor binding; receptor coupling

DESCRIPTION: (Applicant's abstract) This is a revised proposal for a renewal of project NS29514 on the characterization of the phosphoinositide linked dopamine (DA) receptor. Evidence obtained under this grant supports the existence of the brain DA receptor subtype which is linked to the phosphoinositide second messenger pathway. The receptor appears to be a D1/5 like DA receptor, differing from the classically defined dopamine receptor by coupling to phospholipase C via Gq protein. This potentially novel receptor may mediate some of the physiological and pharmacological effects of DA which cannot be accounted for by the adenylyl cyclase-linked DA receptors. Consequently, the understanding of the actions of DA that are mediated via this receptor has potential implications for therapeutics and diagnosis of various DA-associated neuropathologies, including schizophrenia, Parkinsonism, Huntington's chorea and tardive dyskinesia. Characterizing the functional significance of this receptor protein will depend, to a large extent, on the successful cloning of the cDNA which encodes it. The applicant s preliminary efforts to this end resulted in the identification of a cell line which exclusively expresses the principal investigator-linked DA receptor. Obtaining this cell line facilitated the cloning of this unique DNA fragment which contains elements that are highly conserved among all G-protein coupled receptors. A series of experiments are proposed with the following specific aims: (a) to continue and define the components which transduce signals initiated by this receptor in brain tissue, (b) to isolate the full length DNA which encodes this receptor by screening a DNA library constructed from a human cDNA or from the selected cell line, and determine its nucleotide sequence, and restriction map; c) determine the tissue distribution and relative abundance of the novel receptor message in rat brain, and (d) identify its ligand binding and G-protein coupling domains by expressing and analyzing the characteristics of mutant variants of the receptor. The results of this project will lay a solid foundation for the greater understanding of the role of DA in CNS function and dysfunction, and for evaluating and possibly redefining various models of DA-associated neuropathologies.

描述：（申请人的摘要）这是一个修订的建议 在磷酸肌醇的表征上续订NS29514项目NS29514 连接的多巴胺（DA）受体。 根据本赠款支持获得的证据 脑DA受体亚型的存在，与 磷酸肌醇第二信使途径。 受体似乎是 D1/5像DA受体一样，与经典定义的多巴胺不同 通过GQ蛋白与磷脂酶C偶联进行受体。 这可能是 新型受体可以介导一些生理和药理 DA的效果无法通过腺苷环酶连接来解释 DA受体。 因此，对DA行为的理解 通过该受体介导的疗法和 诊断各种DA相关的神经病理学，包括 精神分裂症，帕金森主义，亨廷顿的舞蹈和迟发性运动障碍。 表征该受体蛋白的功能意义将 在很大程度上取决于成功克隆cDNA的克隆 编码它。 申请人为这一目的做出的初步努力导致 仅表达主的细胞系的识别 研究者连接的DA受体。 获得此细胞系有助于 克隆这个独特的DNA片段，其中包含高度的元素 在所有G蛋白偶联受体中保守。 一系列实验 提出了以下特定目的：（a）继续并定义 该受体在大脑中引发的传递信号的组件 组织，（b）分离全长DNA，该DNA通过 筛选由人cDNA构建的DNA库或从选定的 细胞系，并确定其核苷酸序列和限制图； c） 确定新颖的组织分布和相对丰度 大鼠大脑中的受体信息，（d）确定其配体结合和 通过表达和分析特征来通过表达和分析G蛋白耦合结构域 受体的突变变体。 该项目的结果将为 扎实的基础，以更深入地了解DA在CNS中的作用 功能和功能障碍，用于评估并可能重新定义各种 DA相关神经病理学的模型。