Distinct gene expression and secondary metabolite profiles for suboptimal mycorrhizal colonization in wild-type and the jasmonic acid deficient spr2 tomato mutant
- Published
- Accepted
- Subject Areas
- Biotechnology, Ecology, Microbiology, Molecular Biology, Plant Science
- Keywords
- jasmonic acid, gibberellins, arbuscular mycorrhizal colonization, tomatine, ethylene
- Copyright
- © 2019 Casarrubias-Castillo et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2019. Distinct gene expression and secondary metabolite profiles for suboptimal mycorrhizal colonization in wild-type and the jasmonic acid deficient spr2 tomato mutant. PeerJ Preprints 7:e27533v1 https://doi.org/10.7287/peerj.preprints.27533v1
Abstract
A previous study with spr2 mutant tomato plants which are negatively affected in the synthesis of jasmonic acid (JA), suggested that JA regulates the arbuscular mycorrhizal fungi (AMF) colonization via the control of carbon (C) partitioning. Although this and other studies have suggested the important positive role played by JA in the regulation of AMF root colonization in tomato plants, it is currently unclear how different host plant genetic backgrounds affect gene expression and secondary metabolites variation during JA-dependent mycorrhization. In this study, wild type and spr2 mutant tomato plants having “low”, “medium” and “high” mycorrhizal colonization with Rhizophagus irregularis, were analyzed independently using transcriptomic and untargeted metabolomic approaches. The results obtained revealed that the degree of mycorrhizal colonization efficiency could be associated with contrasting expression levels of certain key genes controlling gibberellin signaling, ethylene biosynthesis and signaling, and synthesis of apocarotenoids, phenylpropanoids and tomatine, in roots. Only a few wound responsive genes, including JA signaling and biosynthesis genes, such as Prosystemin and JAZ2 were found to influence AMF colonization. Conversely, a systemic and JA-dependent induction/ repression of genes different from those altered in roots was detected in leaves of mycorrhizal plants. The most significant changes in metabolite abundance were detected in roots with reduced AMF colonization. Included among the latter were metabolites known to be associated with important aspects of AMF symbiosis, such as signaling, nutrient exchange and modulation of pathogen defense response. Αlpha-tomatine levels appeared to be an important factor, whose abundance negatively correlated wit h AMF colonization levels in tomato, suggesting a regulatory role for JA in the synthesis of this metabolite during the AMF symbiosis.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Untargeted principal components analysis on metabolic fingerprinting of mycorrhizal tomato roots
Data were generated from control (CTR) and mycorrhizal (MYC) conditions for the experiment yielding “low” and “high” AMF colonization levels.
Metabolic heat-map analysis
Data were generated with the 100 most intense ions detected in tomato roots under control (CTR) and mycorrhizal (MYC) conditions for the experiment yielding “low” and “high” AMF colonization levels.
qPCR analysis
Oligonucleotides employed for qPCR analysis of AMF colonization related genes.
Metabolomic analysis
Metabolites whose JA-dependent abundance correlated with AMF colonization efficiency.