MATE transporter-dependent export of hydroxycinnamic acid amides
S. ROSAHL (1), M. Dobritzsch (1), K. Gorzolka (1), A. Matern (1), L. Eschen-Lippold (1) (1) Leibniz Institute of Plant Biochemistry, Germany; (2) Leibniz Institute of Plant Biochemistry, Germany

The ability of Arabidopsis thaliana to successfully prevent colonization by Phytophthora infestans, the causal agent of late blight disease of potato, depends on multilayered defense responses. To address the role of plant surface-localized secondary metabolites for pathogen defense, untargeted metabolite profiling was performed. Among the secreted metabolites, we identified the hydroxycinnamic acid amide coumaroylagmatine. Microarray analyses revealed P. infestans-activated and highly co-expressed genes, encoding an agmatine coumaroyl transferase (ACT) and a MATE transporter. In leaves of P. infestans-inoculated act knock out mutants, no coumaroylagmatine was detectable, suggesting that biosynthesis was impaired. In mate mutants, coumaroylagmatine accumulated intra-, but not extracellularly, indicating that the MATE transporter is required for the export of coumaroylagmatine. In Solanum tuberosum, coumaroylagmatine accumulates in response to P. infestans infection in leaves, but not extracellularly, suggesting that potato is not able to secrete coumaroylagmatine efficiently. Expression of both AtACT and AtMATE in transgenic potato plants leads to high levels of extracellular agmatine and putrescine conjugates. This suggests a role of AtMATE for the export of a specific subset of hydroxycinnamic acid amides.

Abstract Number: P15-432
Session Type: Poster