title: Theobroxide Treatment Inhibits Wild Fire Disease Occurrence in Nicotiana benthamiana by the Overexpression of Defense-related Genes.
abstract: Theobroxide, a novel compound isolated from a fungus Lasiodiplodia theobromae, stimulates potato tuber formation and induces flowering of morning glory by initiating the jasmonic acid synthesis pathway. To elucidate the effect of theobroxide on pathogen resistance in plants, Nicotiana benthamiana plants treated with theobroxide were immediately infiltrated with Pseudomonas syringae pv. tabaci. Exogenous application of theobroxide inhibited development of lesion symptoms, and growth of the bacterial cells was significantly retarded. Semi-quantitative RT-PCRs using the primers of 18 defense-related genes were performed to investigate the molecular mechanisms of resistance. Among the genes, the theobroxide treatment increased the expression of pathogenesis-related protein 1a (PR1a), pathogenesis-related protein 1b (PR1b), glutathione S-transferase (GST), allen oxide cyclase (AOC), and lipoxyganase (LOX). All these data strongly indicate that theobroxide treatment inhibits disease development by faster induction of defense responses, which can be possible by the induction of defense-related genes including PR1a, PR1b, and GST triggered by the elevated jasmonic acid.
authors.affiliation: Department of Horticultural Science, Yeungnam University, Gyeongsan 712-749, Korea.
authors.forename: Soon Young
authors.initials: SY
authors.lastname: Ahn
authors.affiliation: School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea ; LED-IT Fusion Technology Research Center, Yeungnam University, Gyeongsan 712-749, Korea.
authors.forename: Kwang-Hyun
authors.initials: KH
authors.lastname: Baek
authors.affiliation: Department of Horticultural Science, Yeungnam University, Gyeongsan 712-749, Korea.
authors.forename: Yong Sun
authors.initials: YS
authors.lastname: Moon
authors.affiliation: Department of Horticultural Science, Yeungnam University, Gyeongsan 712-749, Korea ; LED-IT Fusion Technology Research Center, Yeungnam University, Gyeongsan 712-749, Korea.
authors.forename: Hae Keun
authors.initials: HK
authors.lastname: Yun
keywords: glutathione S-transferase; jasmonic acid; pathogen; pathogenesis-related proteins; theobroxide