转2-CysPrx基因烟草抗氧化酶和PSII电子传递对盐和光胁迫的响应  

Responses of Antioxidant Enzyme and PSII Electron Transport in Leaf of Transgenic Tobacco Carrying 2-Cys Prx to Salt and Light Stresses

作　　者：张会慧[1] 田褀 刘关君[2] 胡彦波[1] 吴翔宇[2] 田野[1] 李鑫[1] 孙广玉[1] 

机构地区：[1]东北林业大学生命科学学院,黑龙江哈尔滨150040 [2]东北林业大学林木遗传育种国家重点实验室,黑龙江哈尔滨150040

出　　处：《作物学报》2013年第11期2023-2029,共7页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(30771746;31070307);哈尔滨市科技创新人才研究专项(2013RFXXJ063);黑龙江省自然科学基金重点项目(ZD2011-05)资助

摘　　要：以转2-Cys Peroxiredoxins(2-Cys Prx)基因的烟草(Nicotiana tabacum)为材料,非转基因烟草为对照,调查盐和光胁迫对转基因烟草幼苗叶片抗氧化酶和叶绿素荧光特性的影响,揭示2-Cys Prx基因在植物抗逆方面的功能。结果表明,弱光(200μmol m 2s 1)下,随着盐浓度增大,转基因烟草和对照的SOD活性皆增加,APX活性变化不大,H2O2含量稍有升高;强光(1000μmol m 2s 1)下,随着盐浓度增大,转基因烟草SOD活性增强,APX活性下降,H2O2含量增加缓慢,而对照的H2O2含量迅速升高,转基因烟草叶片的PSII电子传递速率(ETR)、最大光化学效率(Fv/Fm)和实际光化学效率(PSII)均高于对照,而且PSII电子受体侧的受抑制程度明显低于对照。结果暗示在强光和盐胁迫使APX活性降低的情况下,2-Cys Prx可有效清除细胞中过量H2O2,增强光合电子传递链的稳定性,特别是PSII电子受体侧的电子传递,有效减轻盐和高光胁迫引起的PSII光抑制。2-Cys Peroxiredoxins （2-Cys Prxs） in plants were reported to localize to plant chloroplasts and perform antioxidative function during plant development and photosynthesis. This paper investigated the function of tobacco 2-Cys Prx gene overex- pressed in transgenic tobacco （Nicotiana tabacum） plants with tolerance against light intensity and salt stresses. The results showed that superoxide dismutase （SOD） activity in leaves of two types of tobacco increased under weak light （200 μmolm^-2s^-1） and salt stresses, ascorbateperoxidase （APX） activity changed little, and the content of H2O2 slightly increased. Salt stress en- hanced SOD activity and decreased APX activity under strong light （1000 μmolm^-2s^-1）. The content of H2O2 in leaves of trans- genic tobacco with 2-Cys Prx increased slower than that of wild tobacco. The electron transport rate （ETR）, PSII photochemical efficiency （Fv/Fm） and actual photochemical efficiency （q^sn） in leaves of transgenic tobacco with 2-Cys Prx were higher than those of control under high light. Electron transports in the receptor side were lower than that in control. The results suggested that 2-Cys Prx could be the effective removal of excess H2O2 while APX activity decreased under high light and salt stresses, and could reduce PSII photoinhibition induced by high light and salt stresses.

关 键 词：转2-Cys Prx基因烟草 盐和光胁迫 抗氧化酶 PSII电子传递 

分 类 号：S572[农业科学—烟草工业]