植物生物钟转录抑制子PRRs反馈调节糖信号的分子机理研究

生物钟为植物生长发育提供适应性优势，糖信号调节光合作用等多个关键发育过程，二者之间存在密切互作关系。糖信号通过生物钟转录抑制子PRRs调节生物钟的节律，PRRs也反馈调节糖信号，但目前对PRRs如何反馈调节糖信号尚不清楚。我们前期研究发现，在PRRs突变体中糖信号响应因子TZF1的表达水平显著上调；TZF1超表达植株和PRRs突变体具有相似的生理表型等。本项目将深入研究 PRRs通过调控TZF1转录水平反馈调节糖信号的分子机理，以及TZF1是否反馈调节生物钟节律。研究内容包括：利用ChIP、EMSA和原生质体转化系统等解析PRRs对TZF1基因的表达调控机制；遗传学分析PRRs反馈调节糖信号转导过程中TZF1的作用；基于植物荧光实时成像分析，研究TZF1对生物钟节律的调节等。本研究将揭示生物钟通过PRRs-TZF1信号模块反馈调节糖信号的分子机制，明确在时间维度上糖信号调节的动态过程。

Recent studies have discovered a reciprocal relationship between plant circadian clock and sugar signaling pathways. For example, PRRs(Pseudo Response Regulators) mediated the photosynthetic entrainment of plant circadian clock. However, the feedback regulating mechanism of sugar signaling pathways by circadian clock still remains elusive. In this project, we will decipher its underlying mechanism through establishing the molecular module of PRRs-TZF1 and further investigating the mechanism of their downstream sugar signaling. By combining biochemistry, physiology, genetic and bioinformatics approaches, we are aiming to elucidate the regulation mechanism of PRRs-TZF1 in mediating circadian clock regulation on sugar signaling pathways. The specific research program is: 1) To demonstrate TZF1 is a direct downstream target gene of PRRs by using chromatin immunoprecipitation, yeast one hybrid and protoplast transient system；2）To investigate whether TZF1 mediating circadian output rather than function as central clock component via real-time live bioluminescence image system and RT-qPCR approaches; 3) To explore the necessity of TZF1 in the output of PRRs to regulate sugar signaling pathways by using physiological and genetic analysis. The aim of this project is to explore the molecular mechanism of circadian clock in regulating sugar signal transduction. Our research will elucidate the cross-talk mechanism of the plant circadian clock and sugar signaling and possibly serve as a chronobiological basis for potential agriculture utilization.