Yan Hui, Li Qiang, Park Sung-Chul, Wang Xin, Liu Ya-Ju, Zhang Yun-Gang, Tang Wei, Kou Meng, Ma Dai-Fu
Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District, Key Laboratory for Biology and Genetic Breeding of Sweetpotato (Xuzhou), Ministry of Agriculture/Jiangsu Xuzhou Sweetpotato Research Center, 221131, People's Republic of China.
Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai District, Key Laboratory for Biology and Genetic Breeding of Sweetpotato (Xuzhou), Ministry of Agriculture/Jiangsu Xuzhou Sweetpotato Research Center, 221131, People's Republic of China.
Plant Physiol Biochem. 2016 Dec;109:20-27. doi: 10.1016/j.plaphy.2016.09.003. Epub 2016 Sep 4.
Abiotic stresses cause accumulation of reactive oxygen species (ROS) in plants, CuZnSOD and APX are first line defenses against ROS caused by oxidative stress. In this study, CuZnSOD and APX were transferred into salt sensitive sweet potato (cv. Xushu 55-2) under control of stress inducible SWPA2 promoter and tolerance to salt stress was evaluated. When 100 mM NaCl was used to treat stem cuttings, transgenic plants showed enhanced tolerance compared to wild type (WT) plants. Rooting was significantly retarded in WT plants whereas all transgenic plants had significantly enhanced root growth under salt stress. Integration of SOD gene was confirmed by southern blot analysis, and the copy number ranged from 1 to 3. The expression levels of CuZnSOD and APX in transgenic plants were significantly increased up to 13.3 and 7.8 folds to WT under salinity conditions, respectively. SOD and APX activity and ROS staining showed enzyme activities of transgenic plants were increased under salt stress. These results show that CuZnSOD and APX have important roles in enhancing the salt tolerance of sweet potato.
非生物胁迫会导致植物体内活性氧（ROS）的积累，铜锌超氧化物歧化酶（CuZnSOD）和抗坏血酸过氧化物酶（APX）是抵御氧化应激产生的ROS的第一道防线。在本研究中，在胁迫诱导型SWPA2启动子的控制下，将CuZnSOD和APX转入盐敏感型甘薯（品种：徐薯55-2），并评估其对盐胁迫的耐受性。当用100 mM NaCl处理茎段插条时，与野生型（WT）植株相比，转基因植株表现出更强的耐受性。WT植株的生根明显受阻，而所有转基因植株在盐胁迫下根系生长均显著增强。通过Southern杂交分析证实了SOD基因的整合，拷贝数为1至3。在盐度条件下，转基因植株中CuZnSOD和APX的表达水平分别比WT显著提高了13.3倍和7.8倍。SOD和APX活性以及ROS染色表明，转基因植株在盐胁迫下酶活性增加。这些结果表明，CuZnSOD和APX在增强甘薯耐盐性方面具有重要作用。
