The multisensory guard cell. Stomatal responses to blue light and abscisic acid
The multisensory guard cell. Stomatal responses to blue light and abscisic acid
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DOI：
10.1104/pp.119.3.809
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发表时间：
1999-03-01
期刊：
影响因子：
7.4
通讯作者：
Shimazaki, K
中科院分区：
文献类型：
--
作者：
Assmann, SM;Shimazaki, K
气生植物器官表皮中的微观气孔允许在称为蒸腾的过程中将水蒸气损失到大气中，并允许CO2进入植物进行光合固碳。气孔的开度是由成对的保卫细胞快速而可逆地调节的，保卫细胞界定气孔的边界。这些细胞在双子叶植物和非禾本科单子叶植物中呈肾形，在禾本科植物中呈哑铃形。气孔孔径的精细控制是必不可少的，这样植物既不会经历过度的水分流失和干燥，也不会因CO2而挨饿。这种精细的控制是通过保卫细胞对多种环境和内源性信号的灵敏度来实现的，这些信号包括光、湿度、温度、CO2、植物水分状况和植物激素，特别是阿坝。由于它们被证明具有处理如此多信号的能力，并且由于它们在植物功能中的重要作用，保卫细胞已成为现代植物细胞生物学中的首要模型系统。许多关于保卫细胞生理学的研究都是用蚕豆（Vicia faba）或鸭跖草进行的，因为这些植物的表皮很容易从叶肉组织上剥离。一般来说，气孔孔径扩大时，在保卫细胞的渗透浓度增加驱动水分吸收和保卫细胞肿胀。这种海拔的结果，从吸收钾+和氯，从苹果酸的淀粉分解的合成，并在某些条件下，从积累的蔗糖。由于保卫细胞壁的径向加强，细胞溶胀导致两个保卫细胞分离，从而产生孔径的增加。相反，气孔关闭发生时，溶质从保卫细胞的损失驱动水分损失和保卫细胞放气。在这篇文章中，我们简要地总结了目前的知识，关于两个方面的气孔运动：开放的气孔由蓝光和关闭的气孔由阿坝。
Microscopic stomatal pores in the epidermes of aerial plant organs allow the loss of water vapor to the atmosphere in a process known as transpiration and the entry of CO2 into the plant for photosynthetic carbon fixation. Stomatal apertures are rapidly and reversibly regulated by pairs of guard cells that border and define the pores. These cells are kidney-shaped in dicots and nongraminaceous monocots and dumbbell-shaped in grasses. Fine control of stomatal aperture is essential so that the plant neither undergoes excessive water loss and desiccates nor becomes starved for CO2. This fine control is achieved through an exquisite sensitivity of the guard cells to a multitude of environmental and endogenous signals, including light, humidity, temperature, CO2, plant water status, and plant hormones, particularly ABA. Because of their demonstrated ability to process so many signals, and because of their vital role in plant function, guard cells have become a premier model system in modern plant cell biology. Many studies on guard cell physiology have been conducted with fava bean (Vicia faba) or Commelina communis because of the ease with which the epidermis of these plants can be stripped from the mesophyll tissue. In general, stomatal apertures widen when an increase in the osmotic concentration of the guard cell drives water uptake and guard cell swelling. This elevation in osmoticum results from the uptake of K+ and ClJ, from the synthesis of malate from starch breakdown, and, under some conditions, from the accumulation of Suc. Because of the radial reinforcement of the guard cell wall, cell swelling results in a separation of the two guard cells, thus producing an increase in pore aperture. Conversely, stomatal closure occurs when the loss of solutes from the guard cells drives water loss and guard cell deflation. In this Update, we briefly summarize current knowledge regarding two aspects of stomatal movements: opening of stomata by blue light and closure of stomata by ABA.