QEIB: Collaborative Research: Unifying Mechanistic and Dynamic Mathematical Models of Stomatal Behavior and Photosynthesis.

绿色植物叶片内的光合作用是最著名和研究最多的生物过程之一。在这一系列的化学和物理反应中，光能被用来将大气中的二氧化碳转化为糖，产生氧气作为副产品。因此，光合作用基本上是生物圈中所有有机物和所有氧气的最终来源。从光捕获到碳水化合物合成的78个独立步骤中的每一个都有一些细节，并且描述了它们的动力学性质。为了进行光合作用，二氧化碳必须通过被称为气孔的微小孔隙进入叶片，气孔位于叶片表面。随着CO2扩散到叶片中，水分和O2也随之扩散出去，气孔孔径必须全天动态变化，以便吸收足够的CO2进行光合作用，同时防止水分过多流失。虽然不像光合作用那样为人所熟知，但现在已经描述了许多控制气孔打开的生化和生物物理步骤，并且有新的证据表明光合作用过程可能是许多气孔响应的基础。现在，计算能力和数值方法足以模拟叶片光合作用的整个过程，从二氧化碳和氧气通过气孔交换到光能在底层光合组织中转导成碳水化合物。这项工作首次将光合作用过程的完整描述和气孔运动的假设机制结合在一起，以产生叶片的计算机或计算机表示。这一努力的成果将能够模拟叶片对光线、二氧化碳和氧气变化的动态反应，并与叶片光合作用动态的实际测量结果进行比较，以测试和改进模型。这将为研究气孔运动与光合作用之间的动态联系提供一个平台。更广泛地说，它将提供一种方法来探索一个复杂的自然系统的数学性质，这个系统异常丰富，具有可测量的性质。该项目将通过提供硅叶的入口来促进教育，允许课堂调查动态环境反应和光合作用过程中单个步骤的遗传修饰。与此项目相关的本科生研究经历将有助于门户网站的实施。

Photosynthesis within the leaves of green plants is one of the best known and most researched of biological processes. In this series of chemical and physical reactions, light energy is used to convert atmospheric CO2 into sugars, producing oxygen as a by-product. Thus, photosynthesis is the ultimate source of essentially all organic matter and all oxygen in the biosphere. Each of the 78 discrete steps from light capture to carbohydrate synthesis is known in some detail and their kinetic properties described. For photosynthesis to occur, CO2 must enter the leaf through tiny pores called stomata, which are found on the surfaces of leaves. As CO2 diffuses into the leaf, water and O2 diffuse out, and stomatal aperture must vary dynamically throughout the day to admit sufficient CO2 for photosynthesis while preventing excessive water loss. Although less well understood than photosynthesis, many of the biochemical and biophysical steps controlling stomatal opening are now described, and there is new evidence that photosynthetic processes may underlie many stomatal responses. Computational power and numerical methods are now sufficient to allow the simulation of the complete process of leaf photosynthesis from carbon dioxide and oxygen exchange through the stomata to light energy transduction into carbohydrate in the underlying photosynthetic tissue. This work, for the first time, brings together the complete description of the photosynthetic process and hypothesized mechanisms of stomatal movements to produce a computer or in silico representation of the leaf. The product of this effort will be capable of mimicking the dynamic responses of leaves to changes in light, carbon dioxide and oxygen, and comparisons to real measurements of the dynamics of leaf photosynthesis will be used to test and improve the model. It will provide a workbench for investigating the dynamic linkages between stomatal movement and photosynthesis. More broadly it will provide a means for exploring the mathematical properties of a complex natural system that is unusually rich in measurable properties. The project will contribute to education by providing a portal to the in silico leaf, allowing classroom investigation of both dynamic environmental responses and genetic modification of individual steps in the photosynthetic process. Undergraduate Research Experiences linked to this project will aid this implementation of the portal.