Plant Diversity ›› 2016, Vol. 38 ›› Issue (02): 146-152.

• Articles • Previous Articles    

Jasmonate mediates saltinduced nicotine biosynthesis in tobacco
(Nicotiana tabacum L.)

Xiaodong Chen1,2, Xiaoming Zhang1,3, Aiqun Jia2, Gang Xu1, Hong Hu1, Xiangyang Hu1*, Liwei Hu4*   

  1. 1. Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
    2. School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
    3. University of Chinese Academy of Sciences, Beijing 100049, China
    4. Laboratory of Tobacco Agriculture, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
  • Received:2015-04-17 Revised:2015-11-25 Online:2016-04-25 Published:2016-04-25
  • Supported by:

    Major Science and Technology Program NOs. 110201101003TS03, 2011YN02 and 2011YN03

Abstract:

Jasmonate (JA), as an important signal, plays a key role in multiple processes of plant growth, deve
lopment and stress response. Nicotine and related pyridine alkaloids in tobacco (Nicotiana tabacum L.) are essential secondary metabolites. Whether environmental factors control nicotine biosynthesis and the underlying mechanism remains previously unreported. Here, we applied physiological and biochemical approaches to investigate how salt stress affects nicotine biosynthesis in tobacco. We found that salt stress induced the biosynthesis of JA, which subsequently triggered the activation of JAresponsive gene expression and, ultimately, nicotine synthesis. Bioinformatics analysis revealed the existence of many NtMYC2arecognized Gbox motifs in the promoter regions of NtLOX, NtAOS, NtAOC and NtOPR genes. Applying exogenous JA increased nicotine content, while suppressing JA biosynthesis reduced nicotine biosynthesis. Salt treatment could not efficiently induce nicotine biosynthesis in transgenic antiCOI1 tobacco plants. These results demonstrate that JA acts as the essential signal which triggers nicotine biosynthesis in tobacco after salt stress.

Key words: Tobacco, Jasmonate, Salt stress, Nicotine biosynthesis