H 2 O 2 and NADPH oxidases involve in regulation of 2-(2-phenylethyl)chromones accumulation during salt stress in Aquilaria sinensis calli

• Published in: Plant science (Limerick) 2018-04, Vol.269, p.1
• Main Authors: Wang, Xiaohui, Dong, Xianjuan, Feng, Yingying, Liu, Xiao, Wang, Jinling, Zhang, Zhongxiu, Li, Jun, Zhao, Yunfang, Shi, Shepo, Tu, Pengfei
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Flavonoids - metabolism; Hydrogen Peroxide - metabolism; NADPH Oxidases - chemistry; NADPH Oxidases - genetics; NADPH Oxidases - metabolism; Onium Compounds - pharmacology; Phylogeny; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Sequence Alignment; Sodium Chloride - pharmacology; Stress, Physiological - drug effects; Stress, Physiological - genetics; Thiourea - analogs & derivatives; Thiourea - pharmacology; Thymelaeaceae - genetics; Thymelaeaceae - physiology
• ISSN: 1873-2259

2-(2-Phenylethyl)chromones are the main compounds responsible for the quality of agarwood, which is widely used in traditional medicines, incenses and perfumes. H O and NADPH oxidases (also known as respiratory burst oxidase homologs, Rbohs) mediate diverse physiological and biochemical processes in environmental stress responses. However, little is known about the function of H O and NADPH oxidases in 2-(2-phenylethyl)chromones accumulation. In this study, we found that salt stress induced a transient increase in content of H O and 2-(2-phenylethyl)chromones accumulation in Aquilaria sinensis calli. Exogenous H O remarkably decreased the production of 2-(2-phenylethyl)chromones, while dimethylthiourea (DMTU), a scavenger of H O , significantly increased 2-(2-phenylethyl)chromones accumulation in salt treated calli. Three new H O -generating genes, named AsRbohA-C, were isolated and characterized from A. sinensis. Salt stress also induced a transient increase in AsRbohA-C expression and NADPH oxidase activity. Furthermore, exogenous H O increased AsRbohA-C expression and NADPH oxidase activity, while DMTU inhibited AsRbohA-C expression and NADPH oxidase activity under salt stress. Moreover, diphenylene iodonium (DPI), the inhibitor of NADPH oxidases, reduced AsRbohA-C expression and NADPH oxidase activity, but significantly induced 2-(2-phenylethyl)chromones accumulation during salt stress. These results clearly demonstrated the central role of H O and NADPH oxidases in regulation of salt-induced 2-(2-phenylethyl)chromones accumulation in A. sinensis calli.