《植物生理学报》 2011, 47(6): 613-618

过量表达番茄类囊体膜抗坏血酸过氧化物酶基因(StAPX)提高了烟草种

孙卫红*, 陈相燕, 杜斌, 宋皖, 周越, 王云

江苏大学食品与生物工程学院, 江苏镇江212013

通信作者：孙卫红；E-mail: weihongsun2009@163.com；Tel: 0511-88797059

摘　要：

为了探讨叶绿体类囊体膜抗坏血酸过氧化物酶(tAPX)与其抗氧化性的关系, 从番茄叶片中分离了叶绿体类囊体膜抗 坏血酸过氧化物酶基因(StAPX)并转入到烟草中。以野生型(WT)、转正义StAPX烟草株系T3-3和T3-6为试材, 测定了外源过 氧化氢诱导的氧化胁迫条件下APX酶活性、过氧化氢酶(CAT)活性、过氧化氢(H2O2)含量、叶绿素荧光参数及叶绿素含量 等。Northern杂交显示StAPX基因的表达受外源H2O2氧化胁迫的诱导。氧化胁迫下转基因烟草的APX酶活性和清除H2O2的 能力都显著高于野生型, 并且转基因烟草比野生型具有更高的PSII最大光化学效率及叶绿素含量。结果表明, StAPX的过 量表达有助于提高外源H2O2诱导的转基因烟草的抗氧化能力。

关键词：番茄类囊体膜抗坏血酸过氧化物酶基因; H2O2氧化胁迫; 转基因烟草; 抗氧化能力

收稿：2011-04-11   修定：2011-04-11

资助：江苏省自然科学基金面上项目(BK2010344)、江苏大学高级专业人才科研启动基金(09DJG021)、江苏高校优势学科建设工程项目和国家自然科学基金面上项目 (30871458)。

Tobacco Seedlings Overexpressing StAPX Enhanced Resistance to Oxidative Stress

SUN Wei-Hong*, CHEN Xiang-Yan, DU Bin, SONG Wan, ZHOU Yue, WANG Yun

College of Food and Biological Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China

Corresponding author: SUN Wei-Hong; E-mail: weihongsun2009@163.com; Tel: 0511-88797059

Abstract:

In order to investigate the relationship between thylakoid-bound ascorbate peroxidase (tAPX) and the resistance to oxidative stress, tomato tAPX gene (StAPX) was introduced into tobacco. Wild type (WT), sense-transgenic lines (T₃-3 and T₃-6) of tobacco were used to measure activities of APX and catalase (CAT), contents of hydrogen peroxide (H₂O₂), contents of chlorophyll and chorophyll fluorescence parameters under oxidative stress. Northern blot analysis confirmed that the expression of StAPX was induced by exterior H₂O₂ stress. Activities of APX, the capability for scavenging H₂O₂, maximal photochemistry efficiency of PSII and chlorophyll contents of the transgenic tobacco plants were distinctly higher than those of WT after H₂O₂ treatment. These results indicated that overexpression of StAPX improved exterior H₂O₂-mediated oxidative tolerance in transgenic tobacco plants.

Key words: StAPX; H₂O₂ oxidant stress; transgenic tobacco plant; resistance to oxidant stress