Post-translational control mechanisms of the circadian clock

 描述（由申请人提供）：昼夜节律是几乎普遍存在的内源性计时系统，其有助于协调在一天中的所有时间在每个生物体中连续发生的无数生理、代谢和发育过程。这种生物钟在分子水平上由互锁和自动调节反馈回路组成，这些反馈回路是由复杂的相互作用建立的，这些相互作用在整个24小时周期中不断变化。这个项目的长期目标是了解保持昼夜节律振荡器运行的转录后过程之间的功能关系。我们正在使用遗传学，基因组学，生物化学和细胞生物学的工具和策略的模式植物拟南芥，以确定分子和机制，调节重要的蛋白质和mRNA的细胞质和细胞核之间的运输。我们部分集中在如何一系列的翻译后修饰的时钟蛋白影响其位置和时间的细胞内定位。细胞内环境的守门功能也将得到解决，无论是在基因组规模和在一个单一的分子物种的水平。我们首次在昼夜节律研究中应用单细胞成像技术，使用光开关荧光蛋白来评估将适用于非植物昼夜节律系统的时钟蛋白运动和营业额的特征。我们还利用小RNA加工的某些植物特异性优势来解决生物钟的其他转录后控制机制。总之，我们的计划将探测昼夜节律控制的机制，应该广泛适用于所有真核系统。

 DESCRIPTION (provided by applicant): 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 post- transcriptional processes that keep the circadian oscillator running. 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 important proteins and mRNA between the cytosol and nucleus. We are focused in part on how a range of post-translational modifications of clock proteins affect both their positional and temporal intracellular localization. Gatekeeping features of the intracellular environment will also be addressed, both on a genomic scale 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 photo switchable fluorescent protein to assess features of clock protein movement and turnover that will be applicable to non-plant circadian systems. 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.