Leibniz Institute of Vegetable and Ornamental Crops, Theodor-Echtermeyer-Weg 1, 14979 Großbeeren, Germany.
Leibniz Institute of Vegetable and Ornamental Crops, Theodor-Echtermeyer-Weg 1, 14979 Großbeeren, Germany.
J Proteomics. 2017 Oct 3;169:215-224. doi: 10.1016/j.jprot.2017.04.008. Epub 2017 Apr 18.
The soil-borne fungus Verticillium dahliae is the causal agent of wilting disease and affects a wide range of plant species worldwide. Here, we report on the time-resolved analysis of the tomato root proteome in response to fungal colonization. Tomato (Solanum lycopersicum cv. Hildares) was inoculated with V. dahliae at the two-leaf stage and roots were harvested at 7, 14 and 21 days post inoculation (dpi). In order to identify proteins related to the fungal spread at the different time points, a subsequent proteome analysis by two-dimensional differential gel electrophoresis (2D-DIGE) was conducted on samples from three independent experiments. Hierarchical clustering and k-means clustering of identified proteins distinguished early and late responses to fungal colonization. The results underline that plant defense and adaptation responses are timely coordinated. Proteins involved in oxidative stress were down-regulated at 7 dpi but induced 21 dpi indicating versatile reactive oxygen species signaling interacting with salicylic acid defence signaling at that stage of infection. Drought-stress proteins were induced at 21 dpi, reflecting the beginning of wilting symptoms. Notably, two proteins involved in energy-generating pathways were induced throughout all sampling dates and may reflect the increase in metabolic activity to maintain root growth and, concurrently, activate defense responses.
Mounting of defense responses requires a substantial flux of carbon and nitrogen from primary to secondary metabolites. In-depth understanding of these key metabolic pathways required for growth and defense responses, especially at proteome level, will allow the development of breeding strategies for crops where Verticillium tolerance is absent. Our data show early and late responses of tomato root proteins towards pathogen infection and identify primary metabolism enzymes affected by V. dahliae. Those proteins represent candidates for plant improvement.
土壤真菌黄萎病菌是萎蔫病的病原体，影响全球范围内广泛的植物物种。在这里，我们报告了番茄根蛋白质组在真菌定殖过程中的时间分辨分析。番茄（Solanum lycopersicum cv. Hildares）在两叶期接种黄萎病菌，在接种后 7、14 和 21 天收获根部。为了鉴定与不同时间点真菌扩散相关的蛋白质，我们对来自三个独立实验的样本进行了二维差异凝胶电泳（2D-DIGE）的后续蛋白质组分析。鉴定蛋白质的层次聚类和 k-均值聚类区分了对真菌定殖的早期和晚期反应。结果表明，植物防御和适应反应是及时协调的。7dpi 时，与氧化应激相关的蛋白质下调，但 21dpi 时诱导，表明活性氧信号与水杨酸防御信号在感染的该阶段相互作用。干旱胁迫蛋白在 21dpi 时诱导，反映出萎蔫症状的开始。值得注意的是，两个参与能量生成途径的蛋白质在所有采样日期都被诱导，可能反映了代谢活性的增加，以维持根的生长，并同时激活防御反应。
防御反应的启动需要大量的碳和氮从初级代谢物转移到次生代谢物。深入了解这些对生长和防御反应至关重要的关键代谢途径，特别是在蛋白质组水平上，将允许为缺乏黄萎病菌耐受性的作物开发育种策略。我们的数据显示了番茄根蛋白对病原体感染的早期和晚期反应，并确定了受黄萎病菌影响的初级代谢酶。这些蛋白质代表了植物改良的候选物。
