CAJ | 학술논문

使用外加0.15 W m?2 UV-B及不同钙效应剂处理玉米幼苗,研究细胞Ca2+信号系统对UV-B辐射下玉米幼苗光合作用的调控机制.结果表明, UV诱导的胞内Ca2+荧光增强受胞内IP3通道阻断剂肝素(Heparin)、胞内CaM活性抑制剂三氟啦嗪(TFP)抑制,降低玉米幼苗Chl a、Chl b及Chl a+b含量、原初光能转化效率(Fv/Fm)、PSII活性(Fv/Fo)、Hill 反应活力、水分利用效率(WUE),提高胞间二氧化碳浓度(Ci),最终导致净光合速率(Pn)下降;细胞质膜钙通道阻断剂氯化镧(LaCl3)引发的此效应较小.据此提出, UV-B辐射下,玉米幼苗叶片细胞IP3动员胞内钙库释放Ca2+,调节光合色素合成、Hill反应活性、WUE, CaM介导的下游反应调节Gs,是Ca2+信号系统最终实现对Pn调控的主要机制.
사용외가0.15 W m?2 UV-B급불동개효응제처리옥미유묘,연구세포Ca2+신호계통대UV-B복사하옥미유묘광합작용적조공궤제.결과표명, UV유도적포내Ca2+형광증강수포내IP3통도조단제간소(Heparin)、포내CaM활성억제제삼불랍진(TFP)억제,강저옥미유묘Chl a、Chl b급Chl a+b함량、원초광능전화효솔(Fv/Fm)、PSII활성(Fv/Fo)、Hill 반응활력、수분이용효솔(WUE),제고포간이양화탄농도(Ci),최종도치정광합속솔(Pn)하강;세포질막개통도조단제록화란(LaCl3)인발적차효응교소.거차제출, UV-B복사하,옥미유묘협편세포IP3동원포내개고석방Ca2+,조절광합색소합성、Hill반응활성、WUE, CaM개도적하유반응조절Gs,시Ca2+신호계통최종실현대Pn조공적주요궤제.
UV-B radiation is one of the main adverse environmental factors, obviously affecting plants’ growth and development. Calciumion, as the second messenger in cell signal transduction system, mediates a series of physiological and biochemical reac-tions, which is helpful to alleviate the damage from adverse environmental factors. To investigate the regulational relation be-tween calcium signal system and UV-B radiation in maize, we studied the effects of calcium signal on photosynthesis in maize (Zea mays L.) seedlings under UV-B stress.With the treatments of seedlings growing in natural condition (CK), 0.15 W m?2 UV-B radiation (UV-B), 0.15 W m?2 UV-B radiation+Heparin (UV-B+H), 0.15 W m?2 UV-B radiation+Trifluoperzine (UV-B+TFP), 0.15 W m?2 UV-B radiation+LaCl3 (UV-B+LaCl3), 0.15 W m?2 UV-B radiation+CaCl2 (UV-B+CaCl2), respectively. The Ca2+fluorescence intensity increased rapidly when it was treated with UV-B. However, when the maize leaves were treated with Hepa-rin (intracellular IP3 channel blocker) and Trifluoperazine (intracellular CaM activity inhibitor), the increase of Ca2+fluorescence intensity was inhibited in the mean time, chlorophyll contents, Hill reaction activity, water use efficiency (WUE), efficiency of primary conversion of light energy (Fv/Fm) of PSII, and the potential activity of PSII (Fv/Fo) decreased significantly, which finally leads to the decrease of net photosynthetic rate (Pn). However, LaCl3 (plasma membrane calcium channel blocker) had less effect on it. Therefore, we speculate that under UV-B stress, intercellular IP3/Ca2+system may participate in the process of photosyn-thetic pigments synthesis, water utilization and Hill reaction activity. CaM downstream reaction can regulate Gs, which is con-siderd as the main mechanism that Ca2+signal system eventually achieves the regulation of Pn.