MELATONIN--SITES AND MECHANISMS OF HORMONE ACTION

褪黑激素——激素作用位点和机制

• 批准号: 3243137
• 负责人: STEVEN M. REPPERT
• 金额: $ 23.01万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-08-06 至 1995-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3243137
• 关键词: G protein; affinity labeling; biological signal transduction; bioperiodicity; cell type; chickens; genetic transcription; hamsters; hormone receptor; hormone regulation /control mechanism; immunocytochemistry; in situ hybridization; ion transport; laboratory rabbit; laboratory rat; lizards; melatonin; molecular cloning; phosphorylation; pituitary gland; polymerase chain reaction; protein biosynthesis; protein purification; protein structure function; receptor coupling; receptor expression; receptor sensitivity; second messengers; secretion; sheep; transfection

Melatonin is a pineal hormone with potent biological effects. The experiments proposed in this application represent a focused effort, applying contemporary anatomical, biochemical and molecular techniques to bring our level of understanding of melatonin action up to that of other hormones and neurotransmitters. Our long-term goals include defining the structure of a melatonin receptor and understanding the cellular events of melatonin signal transduction. First, using enriched receptor sources, melatonin receptors will be identified by covalent labeling, purified, and more rigorously characterized in terms of receptor-G protein interactions. Second, using the polymerase chain reaction with degenerate cloned. This will allow stable expression of the receptor protein in a cell line, and examination of structure-function relationships and transcriptional regulation of melatonin receptors. Third, melatonin receptor antibodies and in situ hybridization methods will be developed to study experimental issues regarding the cellular and subcellular distribution of melatonin receptor. Fourth, the intracellular effector systems influenced by melatonin will be fully investigated in dispersed ovine pars tuberalis cells and cells stably transfected with a cDNA encoding a melatonin receptor. This will include examination of acute melatonin effects on chemical second messenger systems, ionic responses and protein phosphorylation. Furthermore, the effects of melatonin on secretory outputs from pars tuberalis will be explored. Fifth, experiments are proposed to bridge the gap between acute responses to receptor occupation and the physiological responses to sustained receptor occupation. This will include studying whether the melatonin receptor undergoes homologous desensitization and whether melatonin alters synthesis or phosphorylation of specific proteins in a duration-dependent manner. Sixth, the mechanisms by which melatonin patterns experienced in the past influence the response to subsequent melatonin patterns will be examined. Understanding the mechanisms of action of melatonin has health implications, as melatonin influences circadian rhythmicity in humans and may be useful for treating biological rhythm disorders. Furthermore, elucidating the mechanisms by which melatonin regulates reproduction in animals that breed seasonally may be of value in delineating general mechanisms for the control of reproduction.

褪黑激素是一种具有有效生物学作用的可刺激激素。 这 本应用程序中提出的实验代表着一项集中精力， 将当代解剖学，生化和分子技术应用于 将我们对褪黑激素作用的理解水平提高到其他 激素和神经递质。 我们的长期目标包括定义 褪黑激素受体的结构并了解 褪黑激素信号转导。 首先，使用富集的受体来源，褪黑激素受体将是 通过共价标记，纯化和更严格地识别 以受体-G蛋白相互作用为特征。 第二，使用 聚合酶链与退化克隆的反应。 这将允许 受体蛋白在细胞系中的稳定表达和检查 结构功能关系和转录调节 褪黑激素受体。 第三，褪黑激素受体抗体和原位 将开发杂交方法来研究实验问题 关于褪黑激素受体的细胞和亚细胞分布。 第四，受褪黑激素影响的细胞内效应系统将是 在分散的椭圆形pars tuberalis细胞和细胞中进行了全面研究 用编码褪黑激素受体的cDNA转染。 这将包括 检查急性褪黑激素对化学二信使的影响 系统，离子反应和蛋白质磷酸化。 此外， 褪黑激素对Tuberalis的分泌产量的影响将是 探索。 第五，提出了实验以弥合急性之间的差距 对受体职业的反应以及对 持续的受体职业。 这将包括研究是否 褪黑激素受体经历同源脱敏，是否 褪黑激素改变A中特定蛋白的合成或磷酸化 持续时间依赖性方式。 第六，褪黑激素的机制 过去经历的模式会影响对随后的反应 褪黑激素模式将进行检查。 了解褪黑激素的作用机制具有健康 含义，褪黑激素会影响人类的昼夜节律和 可能对治疗生物节奏疾病有用。 此外， 阐明褪黑激素调节繁殖的机制 季节性繁殖的动物可能在描述一般中有价值 控制繁殖的机制。