Sukhov Vladimir, Sherstneva Oksana, Surova Lyubov, Katicheva Lyubov, Vodeneev Vladimir
Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, 603950, Nizhny Novgorod, Russia.
Plant Cell Environ. 2014 Nov;37(11):2532-41. doi: 10.1111/pce.12321. Epub 2014 Apr 28.
Electrical signals (action potential and variation potential, VP) caused by environmental stimuli are known to induce various physiological responses in plants, including changes in photosynthesis; however, their functional mechanisms remain unclear. In this study, the influence of VP on photosynthesis in pea (Pisum sativum L.) was investigated and the proton participation in this process analysed. VP, induced by local heating, inactivated photosynthesis and activated respiration, with the initiation of the photosynthetic response connected with inactivation of the photosynthetic dark stage; however, direct VP influence on the light stage was also probable. VP generation was accompanied with pH increases in apoplasts (0.17-0.30 pH unit) and decreases in cytoplasm (0.18-0.60 pH unit), which probably reflected H(+) -ATPase inactivation and H(+) influx during this electrical event. Imitation of H(+) influx using the protonophore carbonyl cyanide m-chlorophenylhydrazone (CCCP) induced a photosynthetic response that was similar with a VP-induced response. Experiments on chloroplast suspensions showed that decreased external pH also induced an analogous response and that its magnitude depended on the magnitude of pH change. Thus, the present results showed that proton cellular influx was the probable mechanism of VP's influence on photosynthesis in pea. Potential means of action for this influence are discussed.
已知环境刺激引起的电信号（动作电位和变异电位，VP）能诱导植物产生各种生理反应，包括光合作用的变化；然而，其功能机制仍不清楚。在本研究中，研究了VP对豌豆（Pisum sativum L.）光合作用的影响，并分析了质子在这一过程中的参与情况。由局部加热诱导产生的VP使光合作用失活并激活呼吸作用，光合作用反应的启动与光合暗反应阶段的失活有关；然而，VP对光反应阶段也可能有直接影响。VP的产生伴随着质外体pH值升高（0.17 - 0.30个pH单位）和细胞质pH值降低（0.18 - 0.60个pH单位），这可能反映了在此电活动过程中H(+) -ATP酶的失活和H(+) 的内流。使用质子载体羰基氰化物间氯苯腙（CCCP）模拟H(+) 内流诱导了与VP诱导反应相似的光合反应。叶绿体悬浮液实验表明，外部pH值降低也诱导了类似的反应，其幅度取决于pH值变化的幅度。因此，目前的结果表明质子细胞内流是VP影响豌豆光合作用的可能机制。讨论了这种影响的潜在作用方式。
