GUARD-CELLS EXTRUDE PROTONS PRIOR TO STOMATAL OPENING - A STUDY USING FLUORESCENCE MICROSCOPY AND PH MICRO-ELECTRODES
GUARD-CELLS EXTRUDE PROTONS PRIOR TO STOMATAL OPENING - A STUDY USING FLUORESCENCE MICROSCOPY AND PH MICRO-ELECTRODES
复制标题
DOI：
10.1093/jxb/39.11.1541
复制
发表时间：
1988-11-01
影响因子：
6.9
通讯作者：
BOWLING, DJF
中科院分区：
文献类型：
--
作者：
EDWARDS, MC;SMITH, GN;BOWLING, DJF
本文描述了质外体中pH变化的一种演示方法。利用荧光pH指示剂报春花素跟踪鸭茅气孔运动过程中叶片表皮的pH变化。先前变暗的叶片在气孔打开前20分钟，在保卫细胞周围的质外体中显示出荧光猝灭。这表明保卫细胞的质子外流先于气孔开放。用pH微电极测量质外体pH证实了这一结果。质外体的酸化从保卫细胞向外扩散到周围的附属细胞和表皮细胞。这种现象在随后的气孔关闭后持续了一段时间，支持了关闭是由质子泵停止以外的其他过程引起的假说。
A method for the demonstration of pH changes in the apoplast is described. The fluorescent pH indicator primulin was used to follow pH changes in the epidermis of leaves of Commelina communis during stomatal movements. Previously darkened leaves exposed to light showed quenching of fluorescence in the apoplast surrounding the guard cells up o 20 min before the stomata opened. This indicated that proton efflux by the guard cells preceded stomatal opening. This result was substantiated by apoplastic pH measurements using pH micro-electrodes. Acidification of the apoplast spread outwards from the guard cells to the surrounding subsidiary and epidermal cells. This phenomenon persisted for some time after subsequent stomatal closure, supporting the hypothesis that closure is brought about by a process other than the cessation of proton pumping.