An elm EST database for identifying leaf beetle egg-induced defense genes

BMC Genomics

Research Article

Jonathan Gershenzon¹  Trevor Fenning²  Torsten Meiners³  Monika Hilker³  Kerstin Büchel⁴  Anne Descour⁵  Carol Soderlund⁵  Will Nelson⁵  Eric McDowell⁶  David R Gang⁶ 

[1] Dept. of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany;Dept. of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany;Forest Research, Northern Research Station, Midlothian, Scotland, UK;Freie Universität Berlin, Applied Zoology / Animal Ecology, Berlin, Germany;Freie Universität Berlin, Applied Zoology / Animal Ecology, Berlin, Germany;Dept. of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany;University of Arizona, BIO5 Institute and Plant Sciences, Tucson, AZ, USA;Washington State University, Institute of Biological Chemistry, Pullman, WA, USA;

关键词: Gene Ontology;    Jasmonic Acid;    Enzyme Commission;    Indirect Defense;    Jasmonic Acid Biosynthesis;   

DOI  :  10.1186/1471-2164-13-242

 received in 2011-11-21, accepted in 2012-05-15,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundPlants can defend themselves against herbivorous insects prior to the onset of larval feeding by responding to the eggs laid on their leaves. In the European field elm (Ulmus minor), egg laying by the elm leaf beetle ( Xanthogaleruca luteola) activates the emission of volatiles that attract specialised egg parasitoids, which in turn kill the eggs. Little is known about the transcriptional changes that insect eggs trigger in plants and how such indirect defense mechanisms are orchestrated in the context of other biological processes.ResultsHere we present the first large scale study of egg-induced changes in the transcriptional profile of a tree. Five cDNA libraries were generated from leaves of (i) untreated control elms, and elms treated with (ii) egg laying and feeding by elm leaf beetles, (iii) feeding, (iv) artificial transfer of egg clutches, and (v) methyl jasmonate. A total of 361,196 ESTs expressed sequence tags (ESTs) were identified which clustered into 52,823 unique transcripts (Unitrans) and were stored in a database with a public web interface. Among the analyzed Unitrans, 73% could be annotated by homology to known genes in the UniProt (Plant) database, particularly to those from Vitis, Ricinus, Populus and Arabidopsis. Comparative in silico analysis among the different treatments revealed differences in Gene Ontology term abundances. Defense- and stress-related gene transcripts were present in high abundance in leaves after herbivore egg laying, but transcripts involved in photosynthesis showed decreased abundance. Many pathogen-related genes and genes involved in phytohormone signaling were expressed, indicative of jasmonic acid biosynthesis and activation of jasmonic acid responsive genes. Cross-comparisons between different libraries based on expression profiles allowed the identification of genes with a potential relevance in egg-induced defenses, as well as other biological processes, including signal transduction, transport and primary metabolism.ConclusionHere we present a dataset for a large-scale study of the mechanisms of plant defense against insect eggs in a co-evolved, natural ecological plant–insect system. The EST database analysis provided here is a first step in elucidating the transcriptional responses of elm to elm leaf beetle infestation, and adds further to our knowledge on insect egg-induced transcriptomic changes in plants. The sequences identified in our comparative analysis give many hints about novel defense mechanisms directed towards eggs.

【 授权许可】

Unknown   
© Büchel et al.; licensee BioMed Central Ltd. 2012. 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.