Evolution of molecular mechanisms that control stomatal closure

叶片中的气孔孔调节光合作用中二氧化碳的吸收和蒸腾作用中水分的损失。这些微小的瓣膜在几乎所有的陆地植物中都有发现，除了苔类植物，这表明它们代表了一种进化的古代对陆地干燥栖息地的适应。在种子植物中，保卫细胞驱动气孔快速关闭的能力是在不利环境条件下生存的基础。尽管气孔对陆地生活方式很重要，但除了种子植物外，人们对保卫细胞的生物学知之甚少。在这个项目中，我们将比较所有四个部门的气孔结果植物的保卫细胞特性。将研究气孔关闭对以下四种刺激的反应：黑暗、高二氧化碳浓度、低空气相对湿度和干旱胁迫激素ABA，它们可能是进化过程中选择的主要标记。我们将结合生理实验、单气孔或保卫细胞技术、分子生物学方法和转录组分析，寻找引起气孔关闭的保卫细胞渗透马达的关键成分。我们的研究将为种子植物产生控制气孔运动的信号网络的进化步骤提供洞察力。

Stomatal pores in leaves regulate carbon dioxide uptake for photosynthesis and the loss of water through transpiration. These microscopic valves are found in virtually all land plants, except for liverworts, suggesting that they represent an evolutionary ancient adaptation to dry terrestrial habitats. In seed plants, the capability of guard cells to drive rapid stomatal closure is fundamental for survival of periods with unfavourable environmental conditions. Despite of the importance of stomata for a terrestrial life style, little is known about the biology of guard cells in divisions other than the seed plants. In this project, we will compare guard cell properties between all four divisions of stomata bearing plants. Stomatal closure responses to the following four stimuli will be studied: darkness, high atmospheric carbon dioxide concentrations, low relative air humidity, and the drought stress hormone ABA, which are likely to represent major markers for selection during evolution. We will combine physiological experiments with single stoma or guard cell techniques with molecular biological methods and transcriptome analysis, to search for key components of the osmotic motor of guard cells that provokes stomatal closure. Our studies will provide insights into the evolutionary steps that gave rise to the signalling networks controlling stomatal movements in seed plants.