Fusarium fujikuroi and Fusarium graminearum are agronomically important plant pathogens, both infecting important staple food plants and thus leading to huge economic losses worldwide. F. fujikuroi belongs to the Fusarium fujikuroi species complex (FFSC) and causes bakanae disease on rice, whereas F. graminearum, a member of the Fusarium graminearum species complex (FGSC), is the causal agent of Fusarium Head Blight (FHB) disease on wheat, barley and maize. In recent years, the importance of chromatin regulation became evident in the plant-pathogen interaction. Several processes, including posttranslational modifications of histones, have been described as regulators of virulence and the biosynthesis of secondary metabolites. In this study, we have functionally characterised methylation of lysine 20 histone 4 (H4K20me) in both Fusarium species. We identified the respective genes solely responsible for H4K20 mono-, di- and trimethylation in F. fujikuroi (FfKMT5) and F. graminearum (FgKMT5). We show that loss of Kmt5 affects colony growth in F. graminearum while this is not the case for F. fujikuroi. Similarly, FgKmt5 is required for full virulence in F. graminearum as Δfgkmt5 is hypovirulent on wheat, whereas the F. fujikuroi Δffkmt5 strain did not deviate from the wild type during rice infection. Lack of Kmt5 had distinct effects on the secondary metabolism in both plant pathogens with the most pronounced effects on fusarin biosynthesis in F. fujikuroi and zearalenone biosynthesis in F. graminearum. Next to this, loss of Kmt5 resulted in an increased tolerance towards oxidative and osmotic stress in both species.

Fusarium fujikuroi和Fusarium graminearum是重要的农艺植物病原体，它们都感染重要的主食植物，从而导致全球巨大的经济损失。F.  fujikuroi属于Fusarium fujikuroi物种复合体 (FFSC) 并在水稻上引起 bakanae 病，而F.  graminearum是禾谷镰刀菌的成员物种复合体 (FGSC) 是小麦、大麦和玉米上镰刀菌头枯病 (FHB) 病害的病原体。近年来，染色质调控的重要性在植物-病原体相互作用中变得明显。几个过程，包括组蛋白的翻译后修饰，已被描述为毒力的调节剂和次生代谢物的生物合成。在这项研究中，我们对两种镰刀菌属中赖氨酸 20 组蛋白 4 (H4K20me) 的甲基化进行了功能表征。我们确定了在F.  fujikuroi ( FfKMT5 ) 和F.  graminearum ( FgKMT5 )中单独负责 H4K20 单甲基化、二甲基化和三甲基化的相应基因）。我们表明 Kmt5 的缺失会影响禾谷镰刀菌的菌落生长，而F. fujikuroi则 不然。类似地，FgKmt5 是禾谷镰刀菌完全毒力所必需的，因为Δ fgkmt5 对小麦是低毒力的，而 F. fujikuroi Δ ffkmt5菌株在水稻感染期间没有偏离野生型。缺乏 Kmt5 对两种植物病原体的次生代谢有明显的影响，对F. fujikuroi的镰刀菌素生物合成和禾谷镰刀菌的玉米赤霉烯酮生物合成影响最显着     . 除此之外，Kmt5 的丢失导致这两个物种对氧化和渗透胁迫的耐受性增加。