Key Lab of Pest Monitoring and Green Management, College of Plant Protection, China Agricultural University, Beijing 100193, China.
Int J Mol Sci. 2021 Jan 7;22(2):552. doi: 10.3390/ijms22020552.
Fungal effectors play important roles in host-pathogen interactions. is an ascomycetous fungus that is responsible for the diseases of hundreds of woody plant species, including apple ring rot, which seriously affects apples worldwide. However, little is known about the effectors of . In this study, we analyzed the genome and predicted 320 candidate effector genes, 124 of which were successfully amplified and cloned. We investigated the effects of these genes on plant cell death in while using a transient expression system. Twenty-four hours after initial inoculation with cells carrying candidate effectors, the infiltrated leaves were challenged with cells carrying the gene. In total, 116 candidate effectors completely inhibited, while one partially inhibited, the programmed cell death (PCD) of induced by BAX, whereas seven candidate effectors had no effect. We then further tested seven candidate effectors able to suppress BAX-triggered PCD (BT-PCD) and found that they all completely inhibited PCD triggered by the elicitors INF1, MKK1, and NPK1. This result suggests that these effectors were activated in order to suppress pathogen-associated molecular pattern-triggered immunity. The signal peptides of these candidate effectors exhibited secretory activity in yeast (pSUC2 vector). Moreover, the respective deletion of and significantly reduced the virulence of . These results suggest that these effectors play important roles in the interaction of with its hosts.
真菌效应物在宿主-病原体相互作用中发挥着重要作用。 是一种子囊菌，可引起包括苹果腐烂环病在内的数百种木本植物病害，该病害严重影响全球苹果产业。然而，对于 的效应物知之甚少。在本研究中，我们分析了 的基因组，并预测了 320 个候选效应基因，其中 124 个成功扩增和克隆。我们使用瞬时表达系统研究了这些基因对植物细胞死亡的影响。携带候选效应基因的 细胞初始接种 24 小时后，用携带 基因的 细胞对渗透叶片进行挑战。共有 116 个候选效应基因完全抑制了 BAX 诱导的细胞程序性死亡（PCD），而一个候选效应基因部分抑制了 PCD，七个候选效应基因没有影响。然后，我们进一步测试了能够抑制 BAX 触发的 PCD（BT-PCD）的七个候选效应基因，发现它们都完全抑制了由诱导物 INF1、MKK1 和 NPK1 触发的 PCD。这一结果表明，这些效应物被激活以抑制病原体相关分子模式触发的免疫反应。这些候选效应物的信号肽在酵母（pSUC2 载体）中具有分泌活性。此外， 和 的缺失显著降低了 的毒力。这些结果表明，这些效应物在 与宿主相互作用中发挥着重要作用。
