Collaborative Research: NSF-BSF: Under Pressure: The evolution of guard cell turgor and the rise of the angiosperms

合作研究：NSF-BSF：压力之下：保卫细胞膨压的进化和被子植物的兴起

• 批准号: 2333889
• 负责人: Craig Brodersen
• 金额: $ 25.89万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-01 至 2027-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2333889&HistoricalAwards=false
• 关键词: Collaborative; Research; NSF; BSF; Under

Stomata are the pores on the surface of leaves through which the CO2 needed for photosynthesis enters. At the same time, stomata are also the main way that plants lose water to the atmosphere. Balancing the ratio of CO2 gained and water lost from leaves is essential for plant survival because unregulated water loss would lead to rapid desiccation and death. Stomata open by increasing the internal turgor pressure of paired “guard” cells, which causes the cells to bow apart creating a hole or pore, and close by reducing guard cell turgor pressure. Despite the key role of turgor pressure in stomatal functioning, progress has been limited by the lack of a method to measure turgor pressures in photosynthesizing leaves. This project introduces a new approach to determine guard cell turgor pressure in which a laser is used to trigger the formation of a gas bubble inside a cell, and the size and speed by which this bubble is pushed back into solution due to the turgor pressure is recorded. This method will be used to quantify the range of guard cell turgor pressure across vascular plants and to elucidate the regulation of stomatal opening and closing in response to environmental stresses such as drought and heatwaves. The research will advance understanding of controls on the productivity and resiliency of terrestrial ecosystems, including agricultural systems important to the U.S. bioeconomy and food security, and provide insights into the evolution of stomatal regulation across diverse plant lineages. The project includes educational and outreach activities with the Harvard Museum of Natural History and the Purdue Agriculture Traveling Exhibit that will reach large public audiences and students from K-12 levels. Training in modern scientific research using state of the art equipment and techniques will include postdoctoral fellows, graduate students, and undergraduate students. Immersive laboratory experiences in summer programs and the development of hands-on demonstrations and teaching modules for multiple grade levels will also be undertaken. The coordinated evolution of increased leaf vascular system efficiency with both a reduction in stomatal size and increase in stomatal number is believed to be one of the critical components of angiosperm dominance since the Cretaceous. Yet, controlling more stomata of smaller size likely imposed new constraints in realizing potential photosynthetic gains conferred by more efficient hydraulics. Using a newly developed method that enables for the first-time direct measurement of guard cell and epidermal cell turgor in situ, the research team will determine if angiosperms maintain higher guard cell turgor, enabling their higher rates of photosynthesis and altering stomatal dynamics and control. These results will be compared to ferns, lycophytes and gymnosperms that have stomata that do not interact mechanically with epidermal cells and used to establish clear and definitive links between guard cell anatomy, hormonal signaling, interaction between adjacent epidermal cells, and hydraulics, all of which have eluded scientists for decades because of a lack of direct leaf cell turgor measurements. The results will reveal fundamental biophysical and physiochemical principles of guard cell control in determining the rate of maximum photosynthesis, but also sensitivity to the environment in response to drought and the protection of the leaf vascular network from hydraulic failure. This will enable the development of a more comprehensive understanding of stomatal biology and leaf physiology, both over evolutionary time but also in response to a rapidly changing climate. Outreach and educational efforts for K-12 and undergraduate students will be conducted in collaboration with the Harvard Museum of Natural History and the Purdue Agriculture Traveling Exhibit. Training in modern scientific research using state of the art equipment and techniques will include postdoctoral fellows and graduate students in a long-running training program in physiological ecology. This project also involves international partnerships via the US-Israel Binational Foundation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

气孔是光合作用所需的二氧化碳表面上的孔。同时，Standa也是植物在大气中损失水的主要方式。平衡所获得的二氧化碳的比率和叶子流失的水对于植物生存至关重要，因为不受管制的水分流失将导致迅速的欲望和死亡。气孔通过增加配对的“后卫”细胞的内部turgor压力而打开，这会导致细胞弯曲产生一个孔或孔，并通过降低后卫细胞库格压力来关闭。尽管Turgor压力在气孔功能中的关键作用，但由于缺乏测量光合作用叶子中turgor压力的方法，进步受到了限制。该项目引入了一种新方法，以确定使用激光来触发电池内部气泡的形成，并将这种气泡推回溶液中，因此由于记录了Turgor压力，因此使用激光触发了气泡的形成。该方法将用于量化跨血管植物的警卫细胞压力的范围，并阐明响应于干旱和热浪等环境应力的静态开口和关闭的调节。这项研究将提高对陆地生态系统生产力和弹性的控制，包括对美国生物经济和粮食安全很重要的农业系统，并为跨不同谱系的天气口调节的演变提供见解。该项目包括与哈佛大学自然历史博物馆以及普渡大学农业旅行展览会的教育和外展活动，该展览将吸引来自K-12级别的大型公众受众和学生。使用最先进的设备和技术的现代科学研究培训将包括博士后研究员，研究生和本科生。还将在夏季计划中的沉浸式实验室经验以及为多年级的动手演示和教学模块的发展。叶片血管系统效率提高的协调演化既降低了脊髓灰质的大小，也是降水量的增加。然而，控制较小尺寸的更多气孔可能在实现了更有效的水库中赋予的潜在光合作用收益方面施加了新的限制。使用新开发的方法，该方法可以首次直接直接测量后卫细胞和表皮细胞的原位测量，研究小组将确定血管是否维持更高的后卫细胞库格，从而使它们的光合作用率更高，并改变了气孔动态和控制。这些结果将与蕨类植物，乳木菌和体育植物进行比较，它们具有与表皮细胞相互作用的气孔，并用来在后卫细胞解剖学，马蹄形信号，邻近的表皮细胞之间的相互作用，水合物之间建立明确而确定的联系，并且在这些水合物之间存在数十十群体，因为这一切都在数十年中，因为缺乏指定的lave tergor turgor turgor turgor turgor turgor turgor turgor turgor。结果将揭示防护细胞控制的基本生物物理和物理原始，以确定最大光合作用的速率，但同时对响应干旱的敏感性以及对叶片血管网络免受水库衰竭的保护。这将使对气门生物学和叶片生理学的更全面理解，既在进化时间，又是为了响应迅速变化的气候。 K-12和本科生的外展和教育工作将与哈佛大学自然历史博物馆和普渡大学农业旅行展览会合作进行。使用最先进的设备和技术的现代科学研究培训将包括博士后研究员和研究生在物理生态学的长期培训计划中。该项目还涉及通过美国 - 以色列双性基金会的国际伙伴关系。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响评估标准，被视为通过评估而被视为珍贵的支持。