Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi 753-8515, Yamaguchi, Japan.
Research Center for Thermotolerant Microbial Resources (RCTMR), Yamaguchi University, Yamaguchi 753-8515, Yamaguchi, Japan.
Int J Mol Sci. 2023 Feb 2;24(3):2941. doi: 10.3390/ijms24032941.
Fusarium wilt, caused by f. sp. (FOL), is a devastating soilborne disease in tomatoes. Magnesium oxide nanoparticles (MgO NPs) induce strong immunity against Fusarium wilt in tomatoes. However, the mechanisms underlying this immunity remain poorly understood. Comparative transcriptome analysis and microscopy of tomato roots were performed to determine the mechanism of MgO NP-induced immunity against FOL. Eight transcriptomes were prepared from tomato roots treated under eight different conditions. Differentially expressed genes were compared among the transcriptomes. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that in tomato roots pretreated with MgO NPs, encoding apoplastic protease and encoding NADPH oxidase were upregulated when challenge-inoculated with FOL. The gene encoding glycine-rich protein 4 (SlGRP4) was chosen for further analysis. was rapidly transcribed in roots pretreated with MgO NPs and inoculated with FOL. Immunomicroscopy analysis showed that SlGRP4 accumulated in the cell walls of epidermal and vascular vessel cells of roots pretreated with MgO NPs, but upon FOL inoculation, SlGRP4 further accumulated in the cell walls of cortical tissues within 48 h. The results provide new insights into the probable mechanisms of MgO NP-induced tomato immunity against Fusarium wilt.
镰刀菌枯萎病是一种由 f. sp. (FOL) 引起的毁灭性土传病害，会严重影响番茄的生长。氧化镁纳米颗粒（MgO NPs）可以诱导番茄对镰刀菌枯萎病产生强烈的免疫反应。然而，这种免疫反应的机制仍不清楚。本研究通过对番茄根系进行比较转录组分析和显微镜观察，以确定 MgO NP 诱导的番茄对 FOL 免疫的机制。从经过八种不同处理的番茄根系中制备了八个转录组。对这些转录组进行差异表达基因比较。京都基因与基因组百科全书富集分析表明，在经 MgO NPs 预处理的番茄根系中，当接种 FOL 时，质外体蛋白酶编码基因和 NADPH 氧化酶编码基因上调。选择编码甘氨酸丰富蛋白 4（SlGRP4）的基因进行进一步分析。在经 MgO NPs 预处理并接种 FOL 的根系中， 基因迅速转录。免疫显微镜分析显示，SlGRP4 在经 MgO NPs 预处理的根表皮和维管束细胞壁中积累，但在接种 FOL 后，SlGRP4 在 48 小时内进一步在皮层组织的细胞壁中积累。研究结果为 MgO NP 诱导番茄对镰刀菌枯萎病产生免疫的可能机制提供了新的见解。
