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 昼夜节律是几乎无处不在的内源性计时系统，有助于协调无数 生理、新陈代谢和发育过程，在每个生物体的所有时间内连续发生 这一天。这个生物钟是在分子水平上组成的互锁和自动调节的反馈 从复杂的交互中构建的循环，这些交互在整个24小时内相对于每个循环不断变化 小时循环。这个项目的长期目标是了解内部和外部之间的功能关系 维持昼夜节律振荡器在整个植物中运行和协调的细胞内过程。我们是 利用模式植物拟南芥的遗传、基因组、生化和细胞生物学工具和策略 确定调节胞浆和胞浆之间时钟蛋白运输的分子和机制 原子核。我们在一定程度上关注时钟蛋白的翻译后修饰如何影响它们的 位置和时间上的细胞内定位。细胞内环境的把关功能，例如 核孔(NP)，使用精选的NP突变体，并在单个分子水平上也被解决 物种。我们首次在昼夜节律研究中应用单细胞成像技术 光开关荧光蛋白用于评估时钟蛋白的运动和周转特性 适用于非植物昼夜节律系统。将探索从地上部到根的长距离昼夜节律信号。 使用精选的光感受器、激酶和葡萄糖信号突变体以及异常分生组织突变体。 无偏突变筛选以确定控制时钟蛋白水平的蛋白降解因子将有助于理解 这些因素的精确时间阶段划分的重要性。我们还在开发某些植物特有的 小RNA处理解决昼夜节律的其他转录后控制机制的优势 钟。综上所述，我们的节目将探索昼夜节律控制的机制，这些机制应该广泛 适用于所有真核系统。