PDF(Pubmed)
Abstract：
Phytophthora pathogens possess hundreds of effector genes that exhibit diverse expression patterns during infection, yet how the expression of effector genes is precisely regulated remains largely elusive. Previous studies have identified a few potential conserved transcription factor binding sites (TFBSs) in the promoters of Phytophthora effector genes. Here, we report a MYB-related protein, PsMyb37, in Phytophthora sojae, the major causal agent of root and stem rot in soybean. Yeast one-hybrid and electrophoretic mobility shift assays showed that PsMyb37 binds to the TACATGTA motif, the most prevalent TFBS in effector gene promoters. The knockout mutant of PsMyb37 exhibited significantly reduced virulence on soybean and was more sensitive to oxidative stress. Consistently, transcriptome analysis showed that numerous effector genes associated with suppressing plant immunity or scavenging reactive oxygen species were down-regulated in the PsMyb37 knockout mutant during infection compared to the wild-type P. sojae. Several promoters of effector genes were confirmed to drive the expression of luciferase in a reporter assay. These results demonstrate that a MYB-related transcription factor contributes to the expression of effector genes in P. sojae.
摘要：
疫霉病原体具有数百个效应基因，在感染过程中表现出不同的表达模式，然而，如何精确调节效应基因的表达在很大程度上仍然难以捉摸。先前的研究已经确定了疫霉效应基因启动子中一些潜在的保守转录因子结合位点(TFBSs)。这里,我们报道了一种MYB相关蛋白,PsMyb37，在大豆疫霉中，大豆根腐病和茎腐病的主要致病因子。酵母单杂交和电泳迁移率变化分析显示，PsMyb37与TACATGTA基序结合，效应基因启动子中最普遍的TFBS。PsMyb37基因敲除突变体对大豆的毒力显著降低,对氧化应激反应更为敏感。始终如一，转录组分析表明，与野生型P.sojae相比，感染期间PsMyb37敲除突变体中许多与抑制植物免疫或清除活性氧相关的效应基因被下调。证实了效应基因的几个启动子在报告基因测定中驱动荧光素酶的表达。这些结果表明，MYB相关转录因子有助于大豆疫霉中效应基因的表达。
