Environmental Biotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-ro, Yusong-gu, Daejeon 305-806, Republic of Korea.
Plant Physiol Biochem. 2011 Aug;49(8):891-7. doi: 10.1016/j.plaphy.2011.04.001. Epub 2011 Apr 8.
Oxidative stress is one of the major causative factors for injury to plants exposed to environmental stresses. Plants have developed diverse defense mechanisms for scavenging oxidative stress-inducing molecules. The antioxidative enzyme 2-cysteine peroxiredoxin (2-Cys Prx) removes peroxides and protects the photosynthetic membrane from oxidative damage. In this study, transgenic potato (Solanum tuberosum L. cv. Atlantic) expressing At2-Cys Prx under control of the oxidative stress-inducible SWPA2 promoter or enhanced CaMV 35S promoter (referred to as SP and EP plants, respectively) was generated using Agrobacterium-mediated transformation. The transgenic plants were tested for tolerance to stress. Following treatment with 3 μM methyl viologen (MV), leaf discs from SP and EP plants showed approximately 33 and 15% less damage than non-transformed (NT) plants. When 300 μM MV was sprayed onto whole plants, the photosynthetic activity of SP plants decreased by 25%, whereas that of NT plants decreased by 60%. In addition, SP plants showed enhanced tolerance to high temperature at 42 °C. After treatment at high temperature, the photosynthetic activity of SP plants decreased by about 7% compared to plants grown at 25 °C, whereas it declined by 31% in NT plants. These results indicate that transgenic potato can efficiently regulate oxidative stress from various environmental stresses via overexpression of At2-Cys Prx under control of the stress-inducible SWPA2 promoter.
氧化应激是导致植物暴露于环境胁迫下受到损伤的主要因素之一。植物已经发展出多种防御机制来清除诱导氧化应激的分子。抗氧化酶 2-半胱氨酸过氧化物酶（2-Cys Prx）可以清除过氧化物，保护光合膜免受氧化损伤。在本研究中，利用农杆菌介导的转化，生成了表达 At2-Cys Prx 的转基因马铃薯（Solanum tuberosum L. cv. Atlantic），其启动子受氧化应激诱导的 SWPA2 启动子或增强型 CaMV 35S 启动子（分别称为 SP 和 EP 植株）的控制。对转基因植株进行了胁迫耐受性测试。用 3 μM 甲紫精（MV）处理后，SP 和 EP 植株的叶片圆盘比非转化（NT）植株分别减少了约 33%和 15%的损伤。当将 300 μM MV 喷洒到整株植物上时，SP 植物的光合作用活性下降了 25%，而 NT 植物下降了 60%。此外，SP 植物对 42°C 的高温表现出增强的耐受性。在高温处理后，与在 25°C 下生长的植物相比，SP 植物的光合作用活性下降了约 7%，而 NT 植物下降了 31%。这些结果表明，通过在氧化应激诱导的 SWPA2 启动子的控制下过表达 At2-Cys Prx，转基因马铃薯可以有效地调节来自各种环境胁迫的氧化应激。
