1 Division of Plant Biology, Department of Biosciences, University of Helsinki, Helsinki, Finland.
2 Department of Forest Sciences, University of Helsinki, Helsinki, Finland.
Antioxid Redox Signal. 2019 Mar 20;30(9):1220-1237. doi: 10.1089/ars.2017.7455. Epub 2018 Jan 24.
Stomata sense the intercellular carbon dioxide (CO) concentration (C) and water availability under changing environmental conditions and adjust their apertures to maintain optimal cellular conditions for photosynthesis. Stomatal movements are regulated by a complex network of signaling cascades where reactive oxygen species (ROS) play a key role as signaling molecules. Recent Advances: Recent research has uncovered several new signaling components involved in CO- and abscisic acid-triggered guard cell signaling pathways. In addition, we are beginning to understand the complex interactions between different signaling pathways.
Plants close their stomata in reaction to stress conditions, such as drought, and the subsequent decrease in C leads to ROS production through photorespiration and over-reduction of the chloroplast electron transport chain. This reduces plant growth and thus drought may cause severe yield losses for agriculture especially in arid areas.
The focus of future research should be drawn toward understanding the interplay between various signaling pathways and how ROS, redox, and hormonal balance changes in space and time. Translating this knowledge from model species to crop plants will help in the development of new drought-resistant crop species with high yields.
气孔根据环境条件的变化感知细胞间的二氧化碳（CO）浓度（C）和水分可用性，并调整其孔径以维持光合作用的最佳细胞条件。气孔运动受信号级联的复杂网络调控，其中活性氧（ROS）作为信号分子发挥关键作用。最新进展：最近的研究揭示了参与 CO 和脱落酸触发保卫细胞信号通路的几个新的信号成分。此外，我们开始了解不同信号通路之间的复杂相互作用。
植物在受到干旱等胁迫条件的反应时会关闭气孔，随后 C 的减少会通过光呼吸和叶绿体电子传递链的过度还原导致 ROS 的产生。这会降低植物的生长速度，因此干旱可能会导致农业，特别是干旱地区的严重减产。
未来研究的重点应该放在理解各种信号通路之间的相互作用上，以及 ROS、氧化还原和激素平衡如何随时间和空间而变化。将这方面的知识从模式物种转化为作物植物，将有助于开发具有高产的新抗旱作物品种。
