Department of Horticultural Science, Yeungnam University, Gyeongsan 712-749, Korea.
School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Korea ; LED-IT Fusion Technology Research Center, Yeungnam University, Gyeongsan 712-749, Korea.
Plant Pathol J. 2013 Mar;29(1):110-5. doi: 10.5423/PPJ.NT.08.2012.0131.
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.
从真菌大丽轮枝菌中分离得到的新型化合物氧化千里光碱，通过启动茉莉酸合成途径，刺激马铃薯块茎形成并诱导牵牛花开花。为了阐明氧化千里光碱对植物病原体抗性的影响，用氧化千里光碱处理的黄花烟植物被立即用丁香假单胞菌 pv.番茄瞬时浸润。外源施用氧化千里光碱抑制了病变症状的发展，并且细菌细胞的生长明显受到抑制。使用防御相关基因的引物进行半定量 RT-PCR，以研究抗性的分子机制。在这些基因中，氧化千里光碱处理增加了病程相关蛋白 1a（PR1a）、病程相关蛋白 1b（PR1b）、谷胱甘肽 S-转移酶（GST）、烯氧合酶（AOC）和脂氧合酶（LOX）的表达。所有这些数据都强烈表明，氧化千里光碱处理通过更快地诱导防御反应来抑制疾病的发展，这可能是通过诱导包括 PR1a、PR1b 和 GST 在内的防御相关基因来实现的，这些基因的诱导是由升高的茉莉酸引发的。
