过量表达StAPX的烟草在百草枯诱导的氧化胁迫下的表现

Performance of Tobacco Plants Overexpressing StAPX under Methylviologen-mediated Oxidative Stress

植株在逆境下经常会遭受氧化胁迫,为了探讨叶绿体抗坏血酸过氧化物酶(tAPX)与其抗氧化性的关系,从番茄叶片中分离得到类囊体膜抗坏血酸过氧化物酶基因(StAPX),利用农杆菌介导的叶盘法并转入烟草中。以野生型(WT),转正义StAPX烟草株系T3-3和T3-6为试材,测定了百草枯(MV)诱导的氧化胁迫条件下APX酶活性、超氧化物歧化酶(SOD)活性、过氧化氢(H2O2)含量、超氧阴离子(O2-)含量、种子发芽率及种苗的生长量变化等。结果表明,氧化胁迫下转基因烟草的种子发芽率、种苗的生长量、抗氧化酶活性和清除活性氧的能力都显著高于野生型。这些结果表明,StAPX的过量表达有助于提高烟草的发芽率及种苗的抗氧化能力。

Plants often suffer oxidative stress under adverse growth conditions.In order to investigate the relationship between chloroplast ascorbate peroxidase（tAPX） and the tolerance to oxidative stress,WT,sense-transgenic lines T3-3 and T3-6 of tobacco were used to measure activities of APX and superoxide dismutase（SOD）,the content of hydrogen peroxide（H2O2） and super-oxide anion radical（O2-）,germination rate of seeds,and capacity of plant growth under oxidative stress.Activities of APX,the capability for scavenging H2O2,seed germination and growth capacity of the transgenic tobacco plants were distinctly higher than those of WT after MV treatment.Overexpression of StAPX in tobacco improved germination rate of seeds and seedling growth capacity under methylviologen-mediated oxidative stress.