共聚焦显微技术研究ABA诱导蚕豆气孔保卫细胞H_2O_2的产生(简报)

STUDIES ON ABA-INDUCED H_2O_2 IN Vicia GUARD CELLS BY MEANS OF CONFOCAL LASER SCANNING MICROSCOPY

逆境下,植物细胞内ABA含量急剧增加,同时植物也可通过一些酶代谢反应积累活性氧,如H2O2,O-2.ABA作为逆境信号对气孔运动的显著调节作用已被诸多实验所证实,但关于其对气孔运动调节的细节还知之甚少.H2O2作为氧化信号分子在植物抗病信号转导中已得到广泛研究[1],但H2O2是否介导保卫细胞的气孔运动还缺乏直接的证据.我们已初步发现H2O2可参与外源ABA诱导的气孔运动过程(资料待发表),但H2O2是不是ABA信号转导链的一个中间成分尚需进一步证实.为此,我们利用H2O2荧光探针乙酰乙酸盐-2,7-二氯氢化荧光素(2,7-dichlorofluorescin diacetate,H2DCFDA)标记蚕豆气孔保卫细胞,并结合激光共聚焦显微术和显微操作术研究ABA诱导蚕豆保卫细胞内H2O2的变化,为H2O2作为氧化信号分子提供证据.

The methods of confocal laser scanning microscopy (CLSM) and microinjection were used to study ABA-induced H2O2 in guard cells ( Vicia faba ), which were labeled with H2O2 specific probe-2, 7-dichlorofluorescin diacetate(H2DCFDA). The results indicated 100U/mL catalase (CAT) could inhibit partly stomatal clasure induced by ABA. 10-3mmol/L ABA could significantly induce H2O2 production in chloroplasl in guard cells of Vicia faba following microinjection, and 100U/mL CAT could partly abolish the effects following simultaneous microinjection of ABA and CAT. These suggest that H2O2 is possibly involved in ABA signaling leading to stomatal closure.