JXB Advance Access originally published online on December 7, 2007
Journal of Experimental Botany 2007 58(15-16):4071-4082; doi:10.1093/jxb/erm263
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
© 2007 The Author(s).
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
This paper is available online free of all access charges (see http://jxb.oxfordjournals.org/open_access.html for further details)
RESEARCH PAPER |
Jasmonates and its mimics differentially elicit systemic defence responses in Nicotiana attenuata
1Department of Molecular Ecology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
2Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, D-07745 Jena, Germany
3University of Warmia and Mazury in Olsztyn, Faculty of Biology, Chair of Plant Physiology and Biotechnology, Oczapowskiego 1A, 10-719 Olsztyn, Poland
* To whom correspondence should be addressed. E-mail: Baldwin{at}ice.mpg.de
Coronalon (6-ethyl indanoyl isoleucine), a synthetic jasmonate mimic, is known to regulate levels of transcripts and secondary metabolites that are commonly elicited by methyl jasmonate (MeJA) in a variety of plants. The ability of coronalon and its derivative (In-L-Ile-Me) to elicit MeJA-activated transcriptional and defence responses [nicotine and trypsin proteinase inhibitors (TPIs)] was compared in treated and systemic untreated tissues of wild-type (WT) and NaLOX3-silenced Nicotiana attenuata plants which are unable to activate either local or systemic defence responses. Coronalon and its derivative significantly regulated 71% and 86% of genes up-regulated by MeJA and 53% and 66% of the genes down-regulated by MeJA in the treated leaves, but only 3% and 7% of all regulated genes in untreated, but phylotactically connected, leaves of WT plants. Consistent with their ability to elicit transcriptional responses in treated tissues, coronalon and In-L-Ile-Me increased nicotine and TPIs when applied to the tissues in which these metabolites are produced, namely roots and leaves. However, treating roots elicited TPI activity in leaves in both WT and NaLOX3-silenced plants, suggesting that mimics can be transported apoplastically from roots to leaves in the xylem. This response was lower in NaLOX3-silenced plants, suggesting that the ability of coronalon and In-L-Ile-Me to elicit TPI responses in leaves after root treatments requires intact jasmonic acid (JA) signalling. Treating leaves did not elicit detectable changes in endogenous JA levels but did decrease free salicylic acid contents. It is concluded that coronalon and In-L-Ile-Me elicit jasmonate responses in treated tissues and could be valuable tools for dissecting local and systemic jasmonate signalling networks in plants.
Key words: Coronalon, 6-ethyl indanoyl isoleucine, indanoyl isoleucine conjugates, MeJA-induced response, Nicotiana attenuata, nicotine, trypsin protease inhibitors
Received 18 August 2007; Accepted 24 September 2007