NaMYC2 transcription factor regulates a subset of plant defense responses in Nicotiana attenuata

BMC Plant Biology

Research Article

Son Truong Dinh¹  Youngjoo Oh¹  Emmanuel Gaquerel¹  Melkamu G Woldemariam¹  Ian T Baldwin¹  Ivan Galis² 

[1]Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans Knöll Straße 8, D-07745, Jena, Germany

[2]Institute of Plant Science and Resources, Okayama University, 2-20-1, 710-0046, Kurashiki, Japan

关键词: bHLH;    Manduca sexta;    MYC2;    Transcription factors;    Nicotiana attenuata;    Nicotine;    Phenolamides;    Plant-insect interactions;    Transcriptional regulation;   

DOI  :  10.1186/1471-2229-13-73

 received in 2013-01-29, accepted in 2013-04-25,  发布年份 2013

来源: Springer

【 摘 要 】

BackgroundTo survive herbivore attack, plants have evolved potent mechanisms of mechanical or chemical defense that are either constitutively present or inducible after herbivore attack. Due to the costs of defense deployment, plants often regulate their biosynthesis using various transcription factors (TFs). MYC2 regulators belong to the bHLH family of transcription factors that are involved in many aspects of plant defense and development. In this study, we identified a novel MYC2 TF from N. attenuata and characterized its regulatory function using a combination of molecular, analytic and ecological methods.ResultsThe transcript and targeted metabolite analyses demonstrated that NaMYC2 is mainly involved in the regulation of the biosynthesis of nicotine and phenolamides in N. attenuata. In addition, using broadly-targeted metabolite analysis, we identified a number of other metabolite features that were regulated by NaMYC2, which, after full annotation, are expected to broaden our understanding of plant defense regulation. Unlike previous reports, the biosynthesis of jasmonates and some JA-/NaCOI1-dependent metabolites (e.g. HGL-DTGs) were not strongly regulated by NaMYC2, suggesting the involvement of other independent regulators. No significant differences were observed in the performance of M. sexta on MYC2-silenced plants, consistent with the well-known ability of this specialist insect to tolerate nicotine.ConclusionBy regulating the biosynthesis of nicotine, NaMYC2 is likely to enhance plant resistance against non-adapted herbivores and contribute to plant fitness; however, multiple JA/NaCOI1-dependent mechanisms (perhaps involving other MYCs) that regulate separate defense responses are likely to exist in N. attenuata. The considerable variation observed amongst different plant families in the responses regulated by jasmonate signaling highlights the sophistication with which plants craft highly specific and fine-tuned responses against the herbivores that attack them.

【 授权许可】

Unknown   
© Woldemariam et al.; licensee BioMed Central Ltd. 2013. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.