茉莉酸类物质(JAs)作为与昆虫啃噬及损伤相关的植物激素和信号分子在植物防御反应中起重要作用,但是茉莉酸引起的早期防御反应的机理仍不清楚.该研究以拟南芥叶片保卫细胞为材料,结合非损伤微测(NMT)及激光共聚焦技术探讨了茉莉酸诱导的保卫细胞中质膜H+-ATPase与H2O2积累的调控关系.结果表明:茉莉酸甲酯(MeJA)处理导致H+迅速跨膜外排和H2O2积累,H+外排和H2O2积累能够被钒酸钠抑制,而二苯基碘(DPI)处理则对MeJA诱导的H+跨膜外排无显著影响.研究结果证明,在MeJA诱导的早期信号事件中,质膜H+-ATPase的激活先于H2O2的产生.
Jasmonate, act as insect herbivore and wounding related plant hormone, play pivotal roles in plant defense and development. However,the mechanism of plant defense induced by MeJA remains unclear. Our studies preliminary reveals the regulation relationship between PM H+-ATPase and H2O2 accumulation. We showed that. MeJA activated the PM H+-ATPase firstly,which resulted the H+ efflux out of cell and cytosolic alkalinization. Further, the increase of cytosolic pH activated the NADPH oxidase, which promo- ted the accumulation of H2O2. These results suggested that the accumulation of H2O2 were regulated by PM H+-ATPase,which would benefit plants for defending against insect attack and pathogen infection.