Research Centre for Plant Metabolomics, Department of Biochemistry, University of Johannesburg, P.O. Box 524, Auckland Park, 2006, Johannesburg, South Africa.
BMC Plant Biol. 2021 Sep 21;21(1):429. doi: 10.1186/s12870-021-03200-5.
Surveillance of potential pathogens is a key feature of plant innate immunity. For non-self-recognition plants rely on the perception of pathogen-derived molecules. Early post-perception events activate signaling cascades, leading to the synthesis of defense-related proteins and specialized metabolites, thereby providing a broad-spectrum antimicrobial coverage. This study was concerned with tracking changes in the tomato plant metabolome following perception of the flagellum-derived elicitors (Flg22 and FlgII-28).
Following an untargeted metabolomics workflow, the metabolic profiles of a Solanum lycopersicum cultivar were monitored over a time range of 16-32 h post-treatment. Liquid chromatography was used to resolve the complex mixture of metabolites and mass spectrometry for the detection of differences associated with the elicitor treatments. Stringent data processing and multivariate statistical tools were applied to the complex dataset to extract relevant metabolite features associated with the elicitor treatments. Following perception of Flg22 and FlgII-28, both elicitors triggered an oxidative burst, albeit with different kinetic responses. Signatory biomarkers were annotated from diverse metabolite classes which included amino acid derivatives, lipid species, steroidal glycoalkaloids, hydroxybenzoic acids, hydroxycinnamic acids and derivatives, as well as flavonoids.
An untargeted metabolomics approach adequately captured the subtle and nuanced perturbations associated with elicitor-linked plant defense responses. The shared and unique features characterizing the metabolite profiles suggest a divergence of signal transduction events following perception of Flg22 vs. FlgII-28, leading to a differential reorganization of downstream metabolic pathways.
潜在病原体的监测是植物先天免疫的一个关键特征。对于非自我识别的植物，它们依赖于对病原体衍生分子的感知。早期的感知后事件会激活信号级联反应，导致防御相关蛋白和特殊代谢物的合成，从而提供广谱的抗菌覆盖。本研究关注的是在番茄植物感知鞭毛衍生激发子（Flg22 和 FlgII-28）后代谢组的变化。
采用非靶向代谢组学工作流程，在 16-32 小时的时间范围内监测了一个 Solanum lycopersicum 品种的代谢谱。采用液相色谱法分离代谢物的复杂混合物，采用质谱法检测与激发子处理相关的差异。严格的数据处理和多变量统计工具被应用于复杂的数据集，以提取与激发子处理相关的相关代谢物特征。在感知 Flg22 和 FlgII-28 后，两种激发子都引发了氧化爆发，尽管它们的动力学反应不同。从不同的代谢物类别中注释了标志性生物标志物，包括氨基酸衍生物、脂质种类、甾体糖苷生物碱、羟基苯甲酸、羟基肉桂酸及其衍生物以及类黄酮。
非靶向代谢组学方法充分捕捉了与激发子相关的植物防御反应相关的微妙和细微的扰动。特征化代谢物图谱的共享和独特特征表明，在感知 Flg22 与 FlgII-28 后，信号转导事件出现分歧，导致下游代谢途径的差异重组。
