Poncini Lorenzo, Wyrsch Ines, Dénervaud Tendon Valérie, Vorley Thomas, Boller Thomas, Geldner Niko, Métraux Jean-Pierre, Lehmann Silke
Department of Biology, University of Fribourg, Fribourg, Switzerland.
Department of Environmental Sciences, University of Basel, Basel, Switzerland.
PLoS One. 2017 Oct 3;12(10):e0185808. doi: 10.1371/journal.pone.0185808. eCollection 2017.
Plants interpret their immediate environment through perception of small molecules. Microbe-associated molecular patterns (MAMPs) such as flagellin and chitin are likely to be more abundant in the rhizosphere than plant-derived damage-associated molecular patterns (DAMPs). We investigated how the Arabidopsis thaliana root interprets MAMPs and DAMPs as danger signals. We monitored root development during exposure to increasing concentrations of the MAMPs flg22 and the chitin heptamer as well as of the DAMP AtPep1. The tissue-specific expression of defence-related genes in roots was analysed using a toolkit of promoter::YFPN lines reporting jasmonic acid (JA)-, salicylic acid (SA)-, ethylene (ET)- and reactive oxygen species (ROS)- dependent signalling. Finally, marker responses were analysed during invasion by the root pathogen Fusarium oxysporum. The DAMP AtPep1 triggered a stronger activation of the defence markers compared to flg22 and the chitin heptamer. In contrast to the tested MAMPs, AtPep1 induced SA- and JA-signalling markers in the root and caused a severe inhibition of root growth. Fungal attack resulted in a strong activation of defence genes in tissues close to the invading fungal hyphae. The results collectively suggest that AtPep1 presents a stronger danger signal to the Arabidopsis root than the MAMPs flg22 and chitin heptamer.
植物通过感知小分子来解读其周围的直接环境。微生物相关分子模式（MAMPs），如鞭毛蛋白和几丁质，在根际中的含量可能比植物来源的损伤相关分子模式（DAMPs）更为丰富。我们研究了拟南芥根如何将MAMPs和DAMPs解读为危险信号。我们监测了在暴露于浓度不断增加的MAMPs鞭毛蛋白flg22、几丁质七聚体以及DAMP AtPep1期间的根发育情况。使用一组报告茉莉酸（JA）、水杨酸（SA）、乙烯（ET）和活性氧（ROS）依赖性信号传导的启动子::YFPN系工具包，分析了根中防御相关基因的组织特异性表达。最后，在根病原体尖孢镰刀菌入侵期间分析了标记反应。与flg22和几丁质七聚体相比，DAMP AtPep1触发了更强的防御标记激活。与测试的MAMPs不同，AtPep1在根中诱导了SA和JA信号标记，并导致根生长严重受抑制。真菌攻击导致入侵真菌菌丝附近组织中的防御基因强烈激活。这些结果共同表明，与MAMPs鞭毛蛋白flg22和几丁质七聚体相比，AtPep1向拟南芥根呈现出更强的危险信号。
