Collaborative Research: Integrated Analysis of the Cell Biological, Biomechanical, and Physiological Dynamics of Stomatal Guard Cells in Plants

在植物中，气孔保护细胞影响光合作用和水分运输，因此对生长和有效利用水分至关重要。然而，我们在细胞和分子水平上对保护细胞功能的理解是有限的。本项目研究保护细胞如何动态扩张和收缩来打开和关闭气孔，控制植物对二氧化碳的吸收和对氧气和水的释放。了解保护细胞的功能将有助于培育出能够在炎热、干燥的环境中生长的高产作物，并更有效地从大气中去除二氧化碳。在这个项目中创建的图像分析和建模工具将使研究人员能够预测细胞的各种机械行为和反应。这个多学科项目将培养三名博士生，他们将成为细胞生物学、计算图像分析、生物系统的机械测试和建模等领域的未来领导者，并将利用K-12和本科生的学习模块和研究经验，传播保护细胞和植物生物学的知识。尽管几十年来的研究兴趣，气孔保护细胞功能的分子和生物物理机制仍然不完全清楚。特别是，保护细胞和邻近细胞的细胞壁和水通量在气孔力学中的作用尚未完全确定。本项目结合分子遗传学、细胞生物学、高级显微镜、计算图像分析、纳米压痕和计算建模，对模式植物拟南芥野生型和突变型气孔综合体的膨胀压力和壁力学进行测量和建模。这些分析将用于研究保护细胞的生物力学以及保护细胞与邻近细胞之间的动态力学和功能关系。该项目的另一个主要目标是使用超分辨率显微镜来绘制保护细胞壁的分子组成和结构的清晰图像，并利用这些数据构建详细、准确和实验可测试的气孔保护细胞的有限元和多尺度、多物理场模型。总之，这项工作将能够预测各种物种、壁面成分、气孔几何形状和信号输入的气孔动力学。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

In plants, stomatal guard cells influence both photosynthesis and water transport and are thus essential for growth and efficient water use. However, our understanding of guard cell function at the cellular and molecular levels is limited. This project studies how guard cells dynamically expand and shrink to open and close stomatal pores, controlling the uptake of carbon dioxide and the release of oxygen and water by the plant. Understanding how guard cells function will aid in the development of resilient, high-yielding crops that can grow in hot, dry environments and more effectively remove carbon dioxide from the atmosphere. The image analysis and modeling tools created in this project will allow researchers to predict the behavior of a wide range of mechanical behaviors and responses by cells. This multidisciplinary project will train three PhD students as future leaders across the topics of cell biology, computational image analysis, and mechanical testing and modeling of biological systems, and will spread knowledge of guard cells and plant biology using learning modules and research experiences for K-12 and undergraduate students.Despite decades of research interest, the molecular and biophysical mechanisms by which stomatal guard cells function remain incompletely understood. In particular, the roles of the cell wall and water flux in guard cells and neighboring cells in stomatal mechanics are not fully defined. This project combines molecular genetics, cell biology, advanced microscopy, computational image analysis, nanoindentation, and computational modeling to measure and model turgor pressure and wall mechanics in wild type and mutant stomatal complexes of the model plant Arabidopsis thaliana. These analyses will be used to examine the biomechanics of guard cells and the dynamic mechanical and functional relationships between guard cells and their neighboring cells. Another major goal of the project is to use super-resolution microscopy to develop a clear picture of the molecular composition and architecture of the guard cell wall, and to use these data to construct detailed, accurate, and experimentally testable finite element and multiscale, multiphysics models of stomatal guard cells. Together, this work will enable the prediction of stomatal dynamics across a range of species, wall compositions, stomatal geometries, and signaling inputs.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.