Collaborative Research: Cellular and Biomechanical Mechanisms of Rapid Stomatal Dynamics in Grasses

气孔是植物表面的微小气孔，是控制作物光合作用的门户，为人类提供食物和可持续材料。该项目研究了包括玉米和小麦等主要粮食作物在内的禾本科植物的气孔是如何构建成具有快速打开和关闭的能力，以调节光合作用和水分运输，以响应不断变化的环境条件。该项目将提供跨学科的研究生培训，并支持分子遗传学、植物细胞生物学、计算机视觉、生物力学实验和建模方面的基于发现的本科研究课程，扩大不同早期职业科学家在这些领域的参与。令人兴奋的植物气孔动力学生物学，以及了解和设计气孔如何帮助应对紧迫的社会挑战，如粮食安全和气候变化，将通过中学夏令营和对将设计和完成独立研究项目的高中生的指导，与K-12学生分享。这项工作的成果有望帮助提高植物捕获二氧化碳的效率，并将其转化为食物和有用的材料，如纤维和木材。草的四细胞气孔复合体被假设为通过一种“拉锯”机制发挥作用，通过这种机制，哑铃形保卫细胞的扩张与保卫细胞两侧的圆形附属细胞的收缩相匹配，从而能够根据环境变化快速调整气孔孔的大小。然而，这一假说还没有得到严格的检验，我们对禾本科植物气孔生物力学和功能的了解也是有限的。这个项目结合了分子遗传学、细胞生物学、计算机视觉、机械测试和气孔生物力学的计算机模拟，剖析了模式草种青冈气孔快速动态的分子、生理和细胞基础。保卫细胞和辅助细胞中细胞壁的组成将通过先进的基因工程在远端短柱藻中进行操纵。将检查由此产生的气孔功能的变化，将测量和模拟改良植物的生物力学特性，并将使用计算机视觉管道来量化细胞体积和形状的变化。有了这些方法，正常和改变的气孔复合体的可实验测试的计算模型将有助于预测如何进一步优化气孔功能，以提高作物产量、水分利用效率和碳吸收。该项目由NSF/BIO/MCB细胞动力学和功能计划以及既定的刺激竞争研究计划(EPSCoR)共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Stomata, which are microscopic pores on the surfaces of plants, are gateways that control photosynthesis in the crops that provide humanity with food and sustainable materials. This project investigates how stomata in grasses, which include staple food crops such as maize and wheat, are constructed with the capability to rapidly open and close to regulate photosynthesis and water transport in response to changing environmental conditions. The project will provide interdisciplinary graduate training and support discovery-based undergraduate research courses in molecular genetics, plant cell biology, computer vision, and biomechanics experimentation and modeling, expanding participation in these fields for diverse early-career scientists. The exciting biology of stomatal dynamics in plants and how understanding and engineering stomata can help address pressing societal challenges such as food security and climate change will be shared with K-12 students through a middle school summer camp and mentoring of high school students who will design and complete independent research projects. The outcomes of this work promise to help improve the efficiency with which plants capture carbon dioxide and convert it into food and useful materials such as fibers and wood.The four-celled stomatal complexes of grasses have been hypothesized to function via a “see-saw” mechanism by which the expansion of dumbbell-shaped guard cells is matched by deflation of the round subsidiary cells that flank the guard cells, enabling rapid adjustment of the size of the stomatal pore in response to environmental shifts. However, this hypothesis has not been rigorously tested, and our understanding of stomatal biomechanics and function in grasses is limited. This project combines molecular genetics, cell biology, computer vision, mechanical testing, and computer modeling of stomatal biomechanics to dissect the molecular, physiological, and cellular underpinnings of rapid stomatal dynamics in a model grass species, Brachypodium distachyon. The composition of the cell walls in guard and subsidiary cells will be manipulated in Brachypodium distachyon through advanced genetic engineering. The resulting changes will be examined with respect to stomatal function, biomechanical properties of the modified plants will be measured and modeled, and computer vision pipelines will be used to quantify changes in cell volumes and shapes. With these approaches, experimentally testable computational models of normal and altered stomatal complexes will help predict how stomatal function might be further optimized to enhance crop yields, water use efficiency, and carbon drawdown.This project is jointly funded by the NSF/BIO/MCB Cell Dynamics & Function Program and the Established Program to Stimulate Competitive Research (EPSCoR).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.