Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, 510642, China.
BMC Genet. 2020 Nov 11;21(1):122. doi: 10.1186/s12863-020-00926-3.
Banana Fusarium wilt is a devastating disease of bananas caused by Fusarium oxysporum f. sp. cubense (Foc) and is a serious threat to the global banana industry. Knowledge of the pathogenic molecular mechanism and interaction between the host and Foc is limited.
In this study, we confirmed the changes of gene expression and pathways in the Cavendish banana variety 'Brazilian' during early infection with Foc1 and Foc4 by comparative transcriptomics analysis. 1862 and 226 differentially expressed genes (DEGs) were identified in 'Brazilian' roots at 48 h after inoculation with Foc1 and Foc4, respectively. After Foc1 infection, lignin and flavonoid synthesis pathways were enriched. Glucosinolates, alkaloid-like compounds and terpenoids were accumulated. Numerous hormonal- and receptor-like kinase (RLK) related genes were differentially expressed. However, after Foc4 infection, the changes in these pathways and gene expression were almost unaffected or weakly affected. Furthermore, the DEGs involved in biological stress-related pathways also significantly differed after infection within two Foc races. The DEGs participating in phenylpropanoid metabolism and cell wall modification were also differentially expressed. By measuring the expression patterns of genes associated with disease defense, we found that five genes that can cause hypersensitive cell death were up-regulated after Foc1 infection. Therefore, the immune responses of the plant may occur at this stage of infection.
Results of this study contribute to the elucidation of the interaction between banana plants and Foc and to the development of measures to prevent banana Fusarium wilt.
香蕉枯萎病是由尖孢镰刀菌古巴专化型（Foc）引起的毁灭性香蕉病害，对全球香蕉产业构成严重威胁。目前对宿主与 Foc 互作的致病分子机制知之甚少。
本研究通过比较转录组分析，证实了 Cavendish 香蕉品种“巴西”在感染 Foc1 和 Foc4 早期的基因表达和通路变化。在接种 Foc1 和 Foc4 48 小时后，巴西根中分别鉴定出 1862 个和 226 个差异表达基因（DEGs）。Foc1 感染后，木质素和类黄酮合成途径被富集。硫代葡萄糖苷、生物碱样化合物和萜类化合物积累。大量激素和受体样激酶（RLK）相关基因差异表达。然而，Foc4 感染后，这些途径和基因表达的变化几乎不受影响或受影响较小。此外，感染两种 Foc 小种后，与生物应激相关途径相关的 DEGs 也显著不同。参与苯丙烷代谢和细胞壁修饰的 DEGs 也有差异表达。通过测量与疾病防御相关基因的表达模式，我们发现，在 Foc1 感染后，有五个能引起过敏细胞死亡的基因上调。因此，植物的免疫反应可能发生在感染的这个阶段。
本研究结果有助于阐明香蕉植株与 Foc 的相互作用，并为开发预防香蕉枯萎病的措施提供依据。
