Molecular genetic analysis of the Arabidopsis circadian clock

拟南芥生物钟的分子遗传学分析

• 批准号: 0960803
• 负责人: C. Robertson McClung
• 金额: $ 10万
• 依托单位: Dartmouth College
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-02-15 至 2011-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0960803&HistoricalAwards=false
• 关键词: Molecular; genetic; analysis; Arabidopsis; circadian

Plants use an internal circadian clock to temporally coordinate biochemical and physiologic activities with the daily cycle imposed by the rotation of the earth on its axis. The matching of this internal clock with the daily environmental cycle contributes significantly to optimal field performance. This research investigates two key aspects of the plant clock mechanism. The first is a genetic and biochemical analysis of temperature compensation, the property by which clock function remains consistent across a range of temperatures. The second is the global regulation of gene expression by the circadian clock. Mutational analysis has identified a novel clock component, AtPRMT5, which encodes a chromatin modification enzyme that serves as a key regulator of gene expression. Specific experimental goals include the identification of targets of PRMT5 activity within the clock mechanism itself and the elucidation of the mechanism by which PRMT5 is regulated. The circadian clock integrates temporal information and coordinates many aspects of biology, including basic metabolism, auxin signaling and responses as well as responses to biotic and abiotic stress. Insights into the molecular details of the clock mechanism will inform an understanding of both the clock mechanism itself as well as of the regulatory network by which temporal information from the clock is used to regulate the expression of suites of genes and coordinate the activities of biochemical pathways. This, in turn, will inform and direct efforts to breed crops whose clock function is optimized for specific environmental (e.g., latitudinal) conditions. Educational efforts will emphasize the training of undergraduate, graduate and post-doctoral scientists able to work comfortably across scales of complexity, from the regulation of expression of individual genes through analyses at the global genomic level.

植物使用内部的生物钟，在时间上协调生物化学和生理活动与地球绕其轴心自转所造成的每日周期。这一内部时钟与每日环境周期的匹配极大地促进了最佳的实地业绩。这项研究调查了植物时钟机制的两个关键方面。第一个是对温度补偿的遗传和生化分析，即时钟功能在一定温度范围内保持一致的特性。第二个是生物钟对基因表达的全球调控。突变分析发现了一个新的时钟成分AtPRMT5，它编码一种染色质修饰酶，该酶是基因表达的关键调节因子。具体的实验目标包括在时钟机制本身内确定PRMT5的活性靶点，以及阐明PRMT5的调节机制。生物钟整合了时间信息，协调了生物学的许多方面，包括基本代谢、生长素信号和响应以及对生物和非生物胁迫的响应。对时钟机制的分子细节的深入了解将有助于理解时钟机制本身以及调控网络，通过该网络，来自时钟的时间信息被用来调节一组基因的表达和协调生化途径的活动。反过来，这将为培育时钟功能针对特定环境(例如，纬度)条件进行优化的作物提供信息并指导努力。教育工作将强调对本科生、研究生和博士后科学家的培训，这些科学家能够在复杂程度上从容地工作，从调节单个基因的表达到在全球基因组水平上进行分析。