Plant Diversity ›› 2016, Vol. 38 ›› Issue (01): 63-69.

• Articles • Previous Articles    

Gamma-aminobutyric acid mediates the nicotine biosynthesis in tobacco under flooding stress

 Xiaoming Zhang1、2, Huaming Lin1, Hong Hu1, Xiangyang Hu1*, Liwei Hu3*   

  1. 1. Germplasm Bank of Wild Species in Southwest China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
    3. Laboratory of Tobacco Agriculture, Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou 450001, China
  • Received:2015-05-11 Online:2016-02-25 Published:2015-06-23
  • Supported by:

    his work was supported by major Science and Technology Program (110201101003TS03, TS0220110014, 2011YN02 and 2011YN03)


Gamma-aminobutyric acid (GABA) is a four-carbon non-protein amino acid conserved from bacteria to plants and vertebrates. Increasing evidence supports a regulatory role for GABA in plant development and the plant′s response to environmental stress. The biosynthesis of nicotine, the main economically important metabolite in tobacco, is tightly regulated. GABA has not hitherto been reported to function in nicotine biosynthesis. Here we found that water flooding treatment (hypoxia) markedly induced the accumulation of GABA and stimulated nicotine biosynthesis. Suppressing GABA accumulation by treatment with glutamate decarboxylase inhibitor impaired flooding-induced nicotine biosynthesis, while exogenous GABA application directly induced nicotine biosynthesis. Based on these results, we propose that GABA triggers nicotine biosynthesis in tobacco seedlings subjected to flooding. Our results provide insight into the molecular mechanism of nicotine biosynthesis in tobacco plants exposed to environmental stress.

Key words: Flooding, Gamma-aminobutyric acid, Nicotine, Tobacco