Virus-induced gene silencing of jasmonate-induced direct defences, nicotine and trypsin proteinase-inhibitors in Nicotiana attenuata.
نویسندگان
چکیده
Research into the molecular basis of plant-insect interactions is hampered by the inability to alter the expression of individual genes in plants growing under natural conditions. The ability of virus-induced gene silencing (VIGS) to silence the expression of two jasmonate-induced genes known to mediate the expression of two potent direct defences (nicotine and proteinase inhibitors) that are produced in different tissues (roots and shoots, respectively) in Nicotiana attenuata is documented here. Fragments of consensus sequences of N. attenuata's putrescine N-methyltransferase (PMT) and trypsin inhibitor (TI) genes were cloned in sense, anti-sense and inverted repeat orientations into the Tobacco Rattle Virus (TRV) to trigger post-transcriptional gene silencing by Agrobacterium-mediated inoculation in plants previously elicited with methyl jasmonate (MeJA) or left as controls. MeJA treatment elicited 2.4- and 9.8-fold increases in the concentrations of nicotine and proteinase inhibitors, respectively, and inoculation with constructs containing appropriate genes inhibited these MeJA-induced increases and halved constitutive accumulations, regardless of the orientation of the gene fragment. Root PMT transcript levels were significantly elevated in MeJA-treated plants 10 h after elicitation, but not in plants inoculated with the appropriate TRV constructs 9 d prior to MeJA treatment, demonstrating that VIGS was responsible for the inhibition of these potent direct defences. While additional research is required to minimize the effects on plant growth and the risks of using such constructs in natural settings, it is concluded that VIGS has a potential to manipulate the expression of genes important for ecological interactions.
منابع مشابه
BAK1 regulates the accumulation of jasmonic acid and the levels of trypsin proteinase inhibitors in Nicotiana attenuata's responses to herbivory
BAK1 is a co-receptor of brassinosteroid (BR) receptor BRI1, and plays a well-characterized role in BR signalling. BAK1 also physically interacts with the flagellin receptor FLS2 and regulates pathogen resistance. The role of BAK1 in mediating Nicotiana attenuata's resistance responses to its specialist herbivore, Manduca sexta, was examined here. A virus-induced gene-silencing system was used ...
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ورودعنوان ژورنال:
- Journal of experimental botany
دوره 55 395 شماره
صفحات -
تاریخ انتشار 2004