Open AccessEffects of overexpression of jasmonic acid biosynthesis genes on nicotine accumulation in tobacco
Author(s) -
Chen Hongxia,
Wang Bingwu,
Geng Sisi,
Arellano Consuelo,
Chen Sixue,
Qu Rongda
Publication year - 2018
Publication title -
plant direct
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.211
H-Index - 11
ISSN - 2475-4455
DOI - 10.1002/pld3.36
Subject(s) - jasmonic acid , nicotine , biosynthesis , arabidopsis , gene , transgene , rna interference , biochemistry , plant defense against herbivory , biology , microbiology and biotechnology , chemistry , rna , neuroscience , mutant
Abstract Nicotine is naturally synthesized in tobacco roots and accumulates in leaves as a defense compound against herbivory attack. Nicotine biosynthesis pathway has been extensively studied with major genes and enzymes being isolated and functionally characterized. However, the molecular regulation of nicotine synthesis has not been fully understood. The phytohormone jasmonic acid ( JA ) mediates many aspects of plant defense responses including nicotine biosynthesis. In this study, five key genes ( At LOX 2 , At AOS , At AOC 2 , At OPR 3 , At JAR 1 ) involved in JA biosynthesis from Arabidopsis were individually overexpressed, and a JA ‐Ile hydrolysis‐related gene, Nt JIH 1 , was suppressed by RNA i approach, to understand their effects on nicotine accumulation in tobacco. Interestingly, while transgene expression was high, levels of JA ‐Ile (the biologically active form of JA ) were often significantly reduced. Meanwhile, nicotine content in these transgenic plants did not increase. The research revealed a tightly controlled JA signaling pathway and a complicated regulatory network for nicotine biosynthesis by JA signaling.