College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Pesticide, Nanjing 210095, Jiangsu Province, China; School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian 223003, Jiangsu Province, China.
Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst 01003, MA, United States.
Pestic Biochem Physiol. 2018 May;147:119-126. doi: 10.1016/j.pestbp.2017.12.007. Epub 2017 Dec 28.
Fusarium oxysporum (Fo) is an important genus of filamentous fungi that causes many devastating diseases of agronomical plants and some opportunistic diseases of humans. Previous studies have indicated that mutations in myosin5 acquired resistance to phenamacril in Fusarium graminearum (Fg). Here, we need to determine the residues of FoMyo5 involved in the natural resistance of plant pathogenic Fo strains. Six kinds of Fo reference strains from different hosts were studied. Fungicide susceptibility testing showed that these Fo strains demonstrated different resistance or susceptibility to phenamacril, which is Fusarium-specific antifungal compound, compared with Fg species. When aligned these homologous myosin5 motor domains of these strains, we found that the substitutions (Val to Ala and Ser to Thr) in FoMyo5 cause natural resistance to phenamacril in the plant pathogenic Fo strains. And we confirmed this result by gene replacement strategy. Such a phenomenon impeded the practical development of this fungicide for controlling vascular wilt diseases.
尖孢镰刀菌（Fusarium oxysporum，Fo）是一种重要的丝状真菌属，可引起许多农业植物的毁灭性疾病和一些人类机会性疾病。先前的研究表明，肌球蛋白 5 的突变可导致禾谷镰刀菌（Fusarium graminearum，Fg）对苯甲酰胺的耐药性。在这里，我们需要确定 FoMyo5 中参与植物病原 Fo 菌株天然抗性的残基。研究了来自不同宿主的六种 Fo 参考菌株。杀菌剂敏感性测试表明，与 Fg 种相比，这些 Fo 菌株对苯甲酰胺表现出不同的耐药性或敏感性，苯甲酰胺是一种特定于镰刀菌的抗真菌化合物。当对这些菌株的同源肌球蛋白 5 马达结构域进行比对时，我们发现 FoMyo5 中的取代（缬氨酸到丙氨酸和丝氨酸到苏氨酸）导致植物病原 Fo 菌株对苯甲酰胺产生天然抗性。我们通过基因替换策略证实了这一结果。这种现象阻碍了该杀菌剂在控制维管束萎蔫病方面的实际发展。
