Photic and Circadian Regulation of Retinal Melatonin

视网膜褪黑素的光和昼夜节律调节

• 批准号: 8601701
• 负责人: Gianluca Tosini
• 金额: $ 35万
• 依托单位: MOREHOUSE SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8601701
• 关键词: Age related macular degeneration; Aging; Animal Model; Automobile Driving; Bioluminescence; Cell Survival; Cells; Circadian Rhythms; Coupled; Data; Development; Disease; Excision; Eye; Functional disorder; Gene Expression; Goals; Inbred C3H Mice; Knockout Mice; Laboratories; Lasers; Lead; Light; Mediating; Melatonin; Melatonin Receptors; Membrane; Microarray Analysis; Microscopy; Molecular; Mus; Pathogenesis; Periodicity; Photoreceptors; Physiological; Play; Proteins; Regulation; Research; Rest; Retina; Retinal; Reverse Transcriptase Polymerase Chain Reaction; Role; Series; Signal Pathway; System; Techniques; Time; Visual; Work; base; circadian pacemaker; ganglion cell; insight; novel therapeutics; photoreceptor disc; prevent; receptor; research study; tool

The mammalian retina contains circadian clocks that regulate multiple aspects of retinal function by driving circadian rhythms of gene expression, photoreceptor outer segment membrane turnover, and visual sensitivity. Previous work has shown that melatonin acting via g protein- coupled melatonin receptors (MTRs) plays a key role in the regulation of a wide variety of retinal circadian rhythms and melatonin is involved in the modulation of retinal cell viability during aging. In the present application we will further investigate the effect of MTR removal on the retina by using melatonin proficient mice (C3H-f+/+) mouse in which the two different types of g- protein coupled melatonin receptors (MTRs) have been removed. These new animal models developed in our laboratory provides a unique and powerful tool with which to investigate the role of melatonin and MTRs in the retina. Our preliminary data suggest that melatonin action within the some retinal cells is likely to be mediated via the formation of melatonin receptor 1 and 2 heteromers (MTRh). The present application comprises three specific aims. In specific aim 1, we will determine whether melatonin receptor type 1 and melatonin receptor type 2 form heteromers in retinal cells. In Specific aim 2, we will investigate the role of melatonin and its associated receptors in the regulation of the daily rhythms in disc shedding in melatonin proficient mice and melatonin receptor knock-out mice. Finally, in specific aim 3 we will determine whether administration of exogenous melatonin increase the sensitivity of the retina to light-induced damage via activation of MTRs and we will dissect the signaling pathways activate by melatonin in the photoreceptor and RPE cells. In our research, we will use a wide array of new and technologically advanced techniques, such as quantitative real time Q-RT- PCR, Bioluminescence Resonance Energy Transfert (BRET), laser capture dissecting microscopy, and microarray analysis. Significance. The characterization of the action of melatonin and its associated receptors may provide new and important insights on the mechanisms of action of melatonin in the eye and more in general in the rest of the body. The experiments proposed in our application will generate data that may lead to the development of new therapeutic tools to treat or prevent disease states associated with dysfunction of the melatonergic system.

哺乳动物视网膜包含调节视网膜功能多个方面的生物钟 通过驱动基因表达的昼夜节律，光感受器外节膜 周转率和视觉敏感性。先前的研究表明，褪黑激素通过 g 蛋白发挥作用 偶联褪黑素受体（MTR）在多种视网膜的调节中发挥着关键作用 昼夜节律和褪黑激素参与调节视网膜细胞活力 老化。在本申请中，我们将进一步研究地铁移除对 视网膜通过使用褪黑激素熟练的小鼠（C3H-f+/+）小鼠，其中两种不同类型的g- 蛋白质偶联褪黑激素受体 (MTR) 已被移除。这些新的动物模型 我们实验室开发的提供了一个独特而强大的工具来研究 褪黑激素和 MTR 在视网膜中的作用。我们的初步数据表明褪黑激素的作用 某些视网膜细胞内的褪黑素受体 1 可能是通过形成来介导的 和 2 个异聚体 (MTRh)。本申请包括三个具体目标。具体来说 目标1，我们将确定褪黑激素受体1型和褪黑激素受体2型是否形成 视网膜细胞中的异聚体。在具体目标 2 中，我们将研究褪黑激素及其作用 褪黑激素中椎间盘脱落调节每日节律的相关受体 熟练小鼠和褪黑激素受体敲除小鼠。最后，在具体目标 3 中，我们将 确定外源性褪黑激素的施用是否会增加视网膜的敏感性 通过激活 MTR 来应对光诱导的损伤，我们将剖析信号通路 由光感受器和 RPE 细胞中的褪黑激素激活。在我们的研究中，我们将广泛使用 一系列新技术和先进技术，例如定量实时 Q-RT- PCR、生物发光共振能量转移 (BRET)、激光捕获解剖 显微镜检查和微阵列分析。 意义。褪黑激素及其相关受体的作用特征可能 为褪黑激素在眼睛中的作用机制提供新的重要见解 在身体的其他部位更普遍。我们的申请中提出的实验将 生成可能导致开发新的治疗工具来治疗或预防的数据 与褪黑激素系统功能障碍相关的疾病状态。