SpBADH of the halophyte Sesuvium portulacastrum strongly confers drought tolerance through ROS scavenging in transgenic Arabidopsis

• Published in: Plant physiology and biochemistry 2015-11, Vol.96, p.377-387
• Main Authors: Yang, Chenglong, Zhou, Yang, Fan, Jie, Fu, Yuhua, Shen, Longbin, Yao, Yuan, Li, Ruimei, Fu, Shaoping, Duan, Ruijun, Hu, Xinwen, Guo, Jianchun
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological; Aizoaceae - genetics; Aizoaceae - metabolism; Aizoaceae - physiology; Arabidopsis - genetics; Arabidopsis - metabolism; Betaine - metabolism; Betaine aldehyde dehydrogenase (BADH); Betaine-Aldehyde Dehydrogenase - genetics; Betaine-Aldehyde Dehydrogenase - metabolism; Catalase - metabolism; Drought stress; Droughts; Environmental stress; Genes, Plant; Glycine betaine; Osmotic Pressure; Plants, Genetically Modified; Reactive oxygen species (ROS); Reactive Oxygen Species - metabolism; Sesuvium portulacastrum; Superoxide Dismutase - metabolism; Transgenic Arabidopsis
• ISSN: 0981-9428; 1873-2690
• DOI: 10.1016/j.plaphy.2015.08.010

Glycine betaine (GB) accumulation is involved in abiotic stress. However, it is not known whether BADH, the key enzyme of GB synthesis, utilizes the antioxidant system to confer drought stress tolerance. In this study, a novel member of the ALDH10 gene family, SpBADH, was isolated from Sesuvium portulacastrum. The expression of this gene was up-regulated by NaCl, PEG6000, H2O2, ABA and high temperature in S. portulacastrum. SpBADH overexpression in Arabidopsis resulted in higher BADH activity and GB content and might increase tolerance to drought/osmotic stresses, specifically strong tolerance to drought stress. Transgenic lines exhibited lower MDA and H2O2 contents but higher proline, POD, SOD and CAT contents than the wild type under drought and osmotic stresses. SpBADH overexpression in Arabidopsis also enhanced the expression of ROS-related genes including AtSOD, AtPOD, AtCAT, AtAPX and Atpsb under drought and osmotic stresses. Thus, SpBADH increases plant tolerance to drought or osmotic stresses by reducing H2O2, increasing proline, and activating antioxidative enzymes to improve ROS scavenging. •SpBADH, from Sesuvium portulacastrum was isolated.•Its expression was up-regulated by NaCl, PEG6000, H2O2, ABA and higher temperature.•Overexpression of SpBADH in Arabidopsis could increase tolerance to drought/osmotic stresses.•SpBADH can activate antioxidative enzymes to improve ROS scavenging.