Hong Tianshu, Wang Shichao, Luo Zhiyuan, Ren Qianqian, Wu Deng, Wang Lulu, Bao Yixue, Yao Wei, Zhang Muqing, Hu Qin
State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Guangxi University, Nanning 530004, China.
Guangxi Key Laboratory of Sugarcane Biology, Nanning 530004, China.
Int J Mol Sci. 2024 Nov 28;25(23):12805. doi: 10.3390/ijms252312805.
The pathogen is responsible for the devastating pokkah boeng disease, which causes significant economic losses in sugarcane production. However, the mechanisms by which it affects plant immunity remain largely unknown. Common in Fungal Extracellular Membrane (CFEM) domain proteins have been implicated in fungal growth, infection processes, and pathogenicity. In this study, we identified three FsCFEM proteins (Fs08184, Fs10706, and Fs13617) that mediate the broad-spectrum suppression of the immune responses induced by typical effectors. A further analysis demonstrated that Fs08184, Fs10706, and Fs13617 suppressed host immunity through two potential iron-binding sites conserved in CFEM family members, characterized by Asp and Phe residues in Fs08184, Fs10706, and Fs13617. Additionally, the Asp and Phe residues within the iron-chelating site were necessary for the iron acquisition of and contributed to creating low-free-iron conditions at the interface of plant and pathogen interactions. It appeared that might employ Asp-Phe-type CFEM members to influence host iron homeostasis to suppress host immunity and to facilitate its successful colonization.
该病原体是造成毁灭性的甘蔗梢腐病的原因，这种病害在甘蔗生产中导致了巨大的经济损失。然而，其影响植物免疫的机制在很大程度上仍不为人知。真菌细胞外膜（CFEM）结构域蛋白与真菌生长、感染过程及致病性有关。在本研究中，我们鉴定出三种FsCFEM蛋白（Fs08184、Fs10706和Fs13617），它们介导对典型效应子诱导的免疫反应的广谱抑制。进一步分析表明，Fs08184、Fs10706和Fs13617通过CFEM家族成员中保守的两个潜在铁结合位点抑制宿主免疫，其特征为Fs08184、Fs10706和Fs13617中的天冬氨酸和苯丙氨酸残基。此外，铁螯合位点内的天冬氨酸和苯丙氨酸残基对于获取铁是必需的，并有助于在植物与病原体相互作用的界面创造低游离铁条件。似乎病原体可能利用天冬氨酸-苯丙氨酸型CFEM成员来影响宿主铁稳态，以抑制宿主免疫并促进其成功定殖。
