Regulatory and Signaling Mechanisms of Crassulacean Acid Metabolism: A Photosynthetic Adaptation to Environmental Stress

景天酸代谢的调节和信号机制：对环境胁迫的光合适应

• 批准号: 0843730
• 负责人: John Cushman
• 金额: $ 98.84万
• 依托单位: Board of Regents, NSHE, obo University of Nevada, Reno
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-01 至 2013-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0843730&HistoricalAwards=false
• 关键词: Regulatory; Signaling; Mechanisms; Crassulacean; Acid

"This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)." Crassulacean acid metabolism (CAM), a photosynthetic pathway found in approximately 7% of all vascular plant species that improves water use efficiency up to 10-fold relative to C3 species, provides an exquisite example of circadian and environmentally regulated photosynthetic adaptation. CAM plants display distinctive circadian clock outputs and inverse stomatal rhythms, which are not found in C3 or C4 plants. The long-term goals of the proposed research are to identify the regulatory and signaling pathways essential for the circadian control of CAM and inverse stomatal behavior, respectively. The common or crystalline ice plant will be used as a model to determine the environmentally induced, circadian controlled changes in mRNA and protein abundance, and reversible protein phosphorylation events during the transition from C3 photosynthesis to CAM by conducting mRNA expression profiling. Metabolite changes will also be monitored to determine if they participate in possible feedback control circuits of upstream circadian clock gene expression outputs. Key regulatory and signaling factors that function in the CAM circadian clock will also be analyzed. Increased understanding of the molecular mechanisms responsible for controlling the expression and regulation of CAM will provide new knowledge about the molecular basis of this important water-saving photosynthetic adaptation that will provide novel strategies for improving crop productivity in the context of global climate change.This project will provide unique 'hands-on' training opportunities in plant research for undergraduate, graduate and post-doctoral students. Undergraduate students will be selected from established outreach programs at the University of Nevada (UNR) that target students from disadvantaged backgrounds to participate in developing a "Plants Have Rhythm" educational display and K-12 teaching module to inform and excite high school, college students, and the general public about CAM and the existence of circadian rhythms in plants and their adaptive significance.

“该奖项的资金来源是《2009 年美国复苏和再投资法案》（公法 111-5）。” 景天酸代谢 (CAM) 是一种光合途径，存在于约 7% 的维管植物物种中，相对于 C3 物种，它的水分利用效率提高了 10 倍，为昼夜节律和环境调节的光合适应提供了一个绝佳的例子。 CAM 植物表现出独特的生物钟输出和逆气孔节律，这是 C3 或 C4 植物中所没有的。本研究的长期目标是分别确定对 CAM 昼夜节律控制和逆气孔行为至关重要的调节和信号传导途径。将使用普通或结晶冰植物作为模型，通过进行 mRNA 表达谱分析，确定环境诱导的、昼夜节律控制的 mRNA 和蛋白质丰度变化，以及从 C3 光合作用到 CAM 过渡期间的可逆蛋白质磷酸化事件。还将监测代谢变化，以确定它们是否参与上游生物钟基因表达输出的可能反馈控制电路。还将分析在 CAM 生物钟中发挥作用的关键调节和信号传导因素。加深对负责控制 CAM 表达和调节的分子机制的了解，将为这种重要的节水光合适应的分子基础提供新的知识，从而为在全球气候变化的背景下提高作物生产力提供新的策略。该项目将为本科生、研究生和博士后提供植物研究方面独特的“实践”培训机会。本科生将从内华达大学 (UNR) 已建立的外展项目中选拔，该项目针对弱势背景的学生，参与开发“植物有节奏”教育展示和 K-12 教学模块，以告知和激发高中生、大学生的兴趣以及公众关于 CAM 和植物昼夜节律的存在及其适应性意义的信息。