M3: Metabolites in systemic acquired resistance

Ivo Feussner & Zhang Yuelin
PhD student: Dmitrij Rekhter


Systemic acquired resistance (SAR) is an evolutionarily conserved defense mechanism induced in the distal parts of plants after a locally restricted primary infection (Fu and Dong, 2013). It confers long-lasting protection against a broad spectrum of microbial pathogens. Salicylic acid (SA) functions as a signal molecule in SAR as well as in local defense responses.
Starting point of the proposed research project is the working hypothesis that the function of genes of unknown function can be identified by metabolomic approaches that will lead to the identification of new metabolites that regulate SAR independent from SA.




We will analyze samples that have prepared by the brush and spray method (Jing et al., 2011) by metabolite fingerprinting using the MarVis workflow (Kaever et al., 2015; König et al., 2014). The basis of this approach will be the hypothesis that mutated genes encode enzymes that are involved in the synthesis of new metabolites that regulate SAR and that the substrates of these enzymes accumulate in the respective mutant background upon pathogen infection.

In parallel, identified genes we will purified after heterologous expression in E. coli. These enzymes will be used to test whether metabolites identified by the metabolite fingerprinting approach are indeed substrates of the enzymes.



References

Fu, Z.Q., and X. Dong: Systemic acquired resistance: Turning local infection into global defense. Annu. Rev. Plant Biol. 64, 839-863 (2013)
Jing, B., S. Xu, M. Xu, Y. Li, S. Li, J. Ding, and Y. Zhang: Brush and spray: A high-throughput systemic acquired resistance assay suitable for large-scale genetic screening. Plant Physiol. 157, 973-980 (2011)
Kaever, A., M. Landesfeind, K. Feussner, A. Mosblech, I. Heilmann, B. Morgenstern, I. Feussner, and P. Meinicke: MarVis-Pathway: integrative and exploratory pathway analysis of non-targeted metabolomics data. Metabolomics 11, 764-777 (2015)
König, S., K. Feussner, A. Kaever, M. Landesfeind, C. Thurow, P. Karlovsky, C. Gatz, A. Polle, and I. Feussner: Soluble phenylpropanoids are involved in the defense response of Arabidopsis against Verticillium longisporum. New Phytol. 202, 823-837 (2014)