COLLABORATIVE RESEARCH: Metabolomic Characterization of Red Light and CO2 Signaling in Guard Cells and Mesophyll Cells

智力优势。该研究小组计划利用现代生物学工具来研究代谢物在红光和二氧化碳（CO2）调节植物叶片表面气孔运动过程中的功能。气孔是由一对高度特化的表皮细胞（称为保卫细胞）包围的微小气孔。气孔运动（由保卫细胞的体积变化实现）控制光合作用的CO2吸收和从植物到大气的水分损失，因此与植物生长、对环境胁迫（如干旱）的适应、农业产量、生物能源和人类生活密切相关。红光和CO2为光合作用和生物质生产提供能量和底物。红光和CO2还通过复杂的细胞内和细胞外信号和代谢网络调节气孔运动。本研究将通过研究保卫细胞合成的代谢物或叶片主要光合细胞分泌的代谢物对这些信号的反应来阐明和分析这些网络。红光和CO2处理后细胞内和细胞外代谢产物的动态变化将被表征并与气孔运动的生理输出相关。该项目预计将识别新的代谢物，将其置于功能背景下，并构建红光和CO2信号转导的预测分子模型。该项目的资源将通过一个可公开访问的网络界面分发，以实现最大的科学影响。预计该项目将对未来提高植物产量和生物能源的生物技术做出积极贡献。预计该项目将产生具有广泛社会影响的成果，例如，从而导致合理的植物代谢工程，以增强胁迫耐受性，获得更多的食物和生物能源。这些结果将有助于加深对植物保卫细胞和光合叶肉细胞代谢和信号传导的理解，揭示调节气孔功能的代谢网络，并推动基础生物科学的发展。该项目期间开发的技术、数据和资源将对其他植物细胞、途径和物种的研究具有直接价值，并将通过网络界面以及出版物和科学会议传播。该项目将为包括高中生、本科生、研究生和博士后科学家在内的现代生物科学前沿人员提供跨学科培训。由于大规模和高通量代谢物分析（代谢组学）仍处于起步阶段，将为全国范围内的研究生和博士后提供一个动手植物代谢组学研讨会/研讨会。来自Chen和Assmann实验室的研究生和博士后科学家将参与开发和运行研讨会，从而获得标准课堂环境之外的宝贵教学经验。将招聘妇女和代表性不足的学生参加培训。总体而言，培训和推广计划旨在整合研究和教育，以帮助下一代植物科学家在代谢组学，计算生物学和系统生物学新兴学科的前沿领域做好准备。

Intellectual Merit. The research team plans to use modern biological tools to investigate the functions of metabolites in the processes of red light and carbon dioxide (CO2) regulated stomatal movement at the plant leaf surface. Stomata are microscopic pores enclosed by pairs of highly specialized epidermal cells called guard cells. Stomatal movements (enabled by volume changes in guard cells) control both CO2 uptake for photosynthesis and water loss from the plant to the atmosphere, and thus are closely related to plant growth, acclimation to environmental stresses such as drought, agricultural yield, bioenergy and human life. Red light and CO2 provide energy and the substrate for photosynthesis and biomass production. Red light and CO2 also regulate stomatal movement via intricate intracellular and extracellular signaling and metabolic networks. This research will elucidate and analyze these networks by studying the roles of metabolites synthesized by the guard cells or secreted by the major photosynthetic cells of the leaf in response to these signals. Dynamic changes of intracellular and extracellular metabolites upon red light and CO2 treatment will be characterized and correlated with the physiological output of stomatal movement. The project is expected to identify novel metabolites, place them in a functional context, and construct predictive molecular models of red light and CO2 signal transduction. The resources from this project will be distributed via a publicly accessible web interface for maximum scientific impact. The project is expected to contribute positively toward future biotechnology of enhanced plant yield and bioenergy.Broader Impacts. This project is expected to generate results with broad societal impact, e.g., leading to rational plant metabolic engineering for enhanced stress tolerance, more food and bioenergy. The results will improve understanding of plant metabolism and signaling in guard cells and photosynthetic mesophyll cells, unravel the metabolic networks regulating stomatal function, and advance basic biological science. The techniques, data and resources developed during the project will be of immediate value to studies of other plant cells, pathways and species and will be disseminated via a web interface as well as in publications and at scientific conferences. The project will provide cross-disciplinary training of personnel, including high school students, undergraduate students, graduate students, and postdoctoral scientists, in the frontiers of modern biological sciences. Because large-scale and high-throughput metabolite analysis (metabolomics) is still in its infancy, a hands-on plant metabolomics workshop/symposium will be offered to graduate students and postdoctorates nationwide. Graduate students and postdoctoral scientists from the Chen and Assmann laboratories will be involved in developing and running the workshop, thus gaining valuable experience in teaching outside the standard classroom setting. Women and under-represented students will be recruited for the training opportunities. Overall, the training and outreach program is designed to integrate research and education to help prepare the next generation of plant scientists in the frontier areas of metabolomics, computational biology and the emerging disciplines of systems biology.