Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu National Agricultural Science and Technology Center, Chengdu, China.
Zhengzhou Research Base, State Key Laboratory of Cotton Biology, Zhengzhou University, Zhengzhou, China.
Mol Plant Pathol. 2021 Oct;22(10):1239-1255. doi: 10.1111/mpp.13108. Epub 2021 Jul 20.
Fusarium oxysporum is the causal agent of the devastating Fusarium wilt by invading and colonizing the vascular system in various plants, resulting in substantial economic losses worldwide. Target of rapamycin (TOR) is a central regulator that controls intracellular metabolism, cell growth, and stress responses in eukaryotes, but little is known about TOR signalling in F. oxysporum. In this study, we identified conserved FoTOR signalling pathway components including FoTORC1 and FoTORC2. Pharmacological assays showed that F. oxysporum is hypersensitive to rapamycin in the presence of FoFKBP12 while the deletion mutant strain ΔFofkbp12 is insensitive to rapamycin. Transcriptomic data indicated that FoTOR signalling controls multiple metabolic processes including ribosome biogenesis and cell wall-degrading enzymes (CWDEs). Genetic analysis revealed that FoTOR1 interacting protein 4 (FoTIP4) acts as a new component of FoTOR signalling to regulate hyphal growth and pathogenicity of F. oxysporum. Importantly, transcript levels of genes associated with ribosome biogenesis and CWDEs were dramatically downregulated in the ΔFotip4 mutant strain. Electrophoretic mobility shift assays showed that FoTIP4 can bind to the promoters of ribosome biogenesis- and CWDE-related genes to positively regulate the expression of these genes. These results suggest that FoTOR signalling plays central roles in regulating hyphal growth and pathogenicity of F. oxysporum and provide new insights into FoTOR1 as a target for controlling and preventing Fusarium wilt in plants.
尖孢镰刀菌通过入侵和定殖各种植物的维管束系统而引起毁灭性的枯萎病，是造成全世界经济损失的主要原因。雷帕霉素靶蛋白（TOR）是一种中央调控因子，控制真核生物的细胞内代谢、细胞生长和应激反应，但对于 TOR 信号在尖孢镰刀菌中的作用知之甚少。在本研究中，我们鉴定了保守的 FoTOR 信号通路成分，包括 FoTORC1 和 FoTORC2。药理试验表明，在存在 FoFKBP12 的情况下，尖孢镰刀菌对雷帕霉素高度敏感，而缺失突变株 ΔFofkbp12 则对雷帕霉素不敏感。转录组数据表明，FoTOR 信号控制多种代谢过程，包括核糖体生物发生和细胞壁降解酶（CWDE）。遗传分析表明，FoTOR1 互作蛋白 4（FoTIP4）作为 FoTOR 信号的新组成部分，调节尖孢镰刀菌的菌丝生长和致病性。重要的是，与核糖体生物发生和 CWDE 相关的基因的转录水平在 ΔFotip4 突变株中显著下调。电泳迁移率变动分析表明，FoTIP4 可以结合到核糖体生物发生和 CWDE 相关基因的启动子上，正向调节这些基因的表达。这些结果表明，FoTOR 信号在调节尖孢镰刀菌的菌丝生长和致病性中起着核心作用，并为将 FoTOR1 作为控制和预防植物枯萎病的靶点提供了新的见解。
