Inter- and intracellular mechanisms of circadian regulation

昼夜节律调节的细胞间和细胞内机制

• 批准号: 10569121
• 负责人: DAVID E SOMERS
• 金额: $ 39万
• 依托单位: OHIO STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10569121
• 关键词: Address; Affect; Arabidopsis; Biochemical; Biological; Biological Models; Cell Cycle; Cell Nucleus; Cells; Circadian Rhythms; Clock protein; Complex; Cytosol; Developmental Process; Environment; Eukaryota; Feedback; Gatekeeping; Genetic; Genomics; Glucose; Goals; Hour; Human; Imaging Techniques; Individual; Link; Malignant Neoplasms; Meristem; Metabolism; Molecular; Movement; Nuclear Pore; Organism; Phase; Phosphotransferases; Photoreceptors; Physiological Processes; Plant Model; Plants; Post-Transcriptional Regulation; Post-Translational Protein Processing; Process; Proteins; RNA Processing; Running; Signal Transduction; Small RNA; System; Time; cellular imaging; circadian; circadian pacemaker; circadian regulation; mutant; programs; tool

Project Summary Circadian rhythms are nearly ubiquitous endogenous timing systems that help coordinate the myriad physiological, metabolic and developmental processes that occur continuously in each organism at all times of the day. This circadian clock is comprised at the molecular level of interlocked and autoregulatory feedback loops that are built from complex interactions that are constantly changing in relation to each throughout the 24 hour cycle. The long term goal of this project is to understand the functional relationships among the inter- and intracellular processes that keep the circadian oscillator running and coordinated across the plant. We are using genetic, genomic, biochemical and cell biological tools and strategies of the model plant Arabidopsis to identify the molecules and mechanisms that regulate the transport of clock proteins between the cytosol and nucleus. We are focused in part on how post-translational modifications of clock proteins affect both their positional and temporal intracellular localization. Gatekeeping features of the intracellular environment, such as the nuclear pore (NP), are also addressed, using select NP mutants, and at the level of a single molecular species. We are applying for the first time in circadian studies single cell imaging techniques using a photoswitchable fluorescent protein to assess features of clock protein movement and turnover that will be applicable to non-plant circadian systems. Long-distance circadian signaling from shoot to root will be explored using select photoreceptor, kinase and glucose-signaling mutants as well as aberrant meristem mutants. Unbiased mutant screens to identify proteolytic factors controlling clock protein levels will help understand the importance of precise time-of-day phasing of these factors. We are also exploiting certain plant-specific advantages of small RNA processing to address other post-transcriptional control mechanisms of the circadian clock. Taken together our program will probe mechanisms of circadian control that should be broadly applicable across all eukaryotic systems.

项目摘要 昼夜节律几乎是无处不在的内源性计时系统，有助于协调众多 生理，代谢和发育过程在每个生物的始终发生 一天。该昼夜节律在互锁和自动调节反馈的分子水平上包括 循环是由复杂互动构建的，这些互动在整个24个中都在不断变化 小时周期。该项目的长期目标是了解间和之间的功能关系 细胞内过程，使昼夜节律振荡器在整个工厂中运行并协调。我们是 使用遗传，基因组，生化和细胞生物学工具以及模型植物拟南芥的策略 确定调节胞质和细胞质之间时钟蛋白转运的分子和机制 核。我们专注于一定程度上的翻译后时钟蛋白的修饰 位置和颞细胞内定位。细胞内环境的守门特征，例如 还使用选择的NP突变体，在单个分子的水平上处理核孔（NP） 物种。我们是在昼夜研究中首次申请的单细胞成像技术 可拍摄的可开关荧光蛋白，以评估时钟蛋白运动和周转的特征 适用于非植物昼夜节律系统。将探索从射击到根的长途昼夜节律信号传导 使用精选的感受器，激酶和葡萄糖信号突变体以及异常分生组织突变体。 公正的突变筛选以鉴定控制时钟蛋白水平的蛋白水解因子将有助于了解 这些因素的精确时间分阶段的重要性。我们还利用某些特定植物的 小型RNA处理的优点是解决昼夜节律的其他转录后控制机制 钟。总而言之，我们的计划将探究昼夜节律控制的机制 适用于所有真核系统。