Indian Institute of Vegetable Research, P.O. Jakhini-Shahanshahpur, Varanasi 221 305, India.
Plant Physiol Biochem. 2013 Aug;69:90-100. doi: 10.1016/j.plaphy.2013.05.002. Epub 2013 May 15.
Transgenic tomato lines (cv. Kashi Vishesh) over-expressing AtDREB1A/CBF3 driven by stress-inducible rd29A promoter showed significantly higher activities of key antioxidant enzymes when exposed to water-deficit for 7, 14, and 21 days. Transgenic tomato plants exposed to water-deficit recorded lower levels of hydrogen peroxide and superoxide anion formation compared to the non-transgenic plants, suggesting alleviation of reactive oxygen species (ROS). A significant increase in activities of enzymes superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), dehydroascorbate reductase (DHAR), and monodehydroascorbate reductase (MDHAR) was observed in response to the different durations of water-deficit conditions. In contrast, enzyme guaiacol peroxidase (POD) activity was lower in the transgenic lines and showed a negative correlation with ROS, ascorbic acid (AsA), and glutathione levels. The concentrations of AsA, glutathione and their reduced forms were higher in the transgenic plants and increased with ROS levels. These results indicate that AtDREB1A transgenic tomato lines are better adapted to water-deficit as they showed lower drought-induced oxidative stress due to activation of the antioxidant response.
转 AtDREB1A/CBF3 基因番茄（cv. Kashi Vishesh）品系在 rd29A 启动子驱动下表达，在干旱胁迫 7、14 和 21 天时，关键抗氧化酶的活性显著升高。与非转基因植株相比，干旱胁迫下的转基因番茄植株形成的过氧化氢和超氧阴离子水平较低，这表明活性氧（ROS）得到了缓解。超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）、谷胱甘肽还原酶（GR）、脱氢抗坏血酸还原酶（DHAR）和单脱氢抗坏血酸还原酶（MDHAR）等酶的活性在不同的干旱胁迫时间下均有显著增加。相反，转基因系中愈创木酚过氧化物酶（POD）的活性较低，与 ROS、抗坏血酸（AsA）和谷胱甘肽水平呈负相关。在转基因植株中，AsA、谷胱甘肽及其还原形式的浓度较高，且随着 ROS 水平的增加而增加。这些结果表明，AtDREB1A 转基因番茄品系更能适应干旱胁迫，因为它们通过激活抗氧化反应表现出较低的干旱诱导氧化应激。
