PDF(Pubmed)
Abstract：
APSES (Asm1p, Phd1p, Sok2p, Efg1p, and StuAp) family transcription factors play crucial roles in various biological processes of fungi, however, their functional characterization in phytopathogenic fungi is limited. In this study, we explored the role of SsStuA, a typical APSES transcription factor, in the regulation of cell wall integrity (CWI), sclerotia formation and pathogenicity of Sclerotinia sclerotiorum, which is a globally important plant pathogenic fungus. A deficiency of SsStuA led to abnormal phosphorylation level of SsSmk3, the key gene SsAGM1 for UDP-GlcNAc synthesis was unable to respond to cell wall stress, and decreased tolerance to tebuconazole. In addition, ΔSsStuA was unable to form sclerotia but produced more compound appressoria. Nevertheless, the virulence of ΔSsStuA was significantly reduced due to the deficiency of the invasive hyphal growth and increased susceptibility to hydrogen peroxide. We also revealed that SsStuA could bind to the promoter of catalase family genes which regulate the expression of catalase genes. Furthermore, the level of reactive oxygen species (ROS) accumulation was found to be increased in ΔSsStuA. In summary, SsStuA, as a core transcription factor involved in the CWI pathway and ROS response, is required for vegetative growth, sclerotia formation, fungicide tolerance and the full virulence of S. sclerotiorum.
摘要：
APSES(Asm1p,Phd1p,Sok2p,Efg1p,和StuAp)家族转录因子在真菌的各种生物过程中起着至关重要的作用,然而,它们在植物病原真菌中的功能特征是有限的。在这项研究中,我们探讨了SsStuA的作用,一种典型的APSES转录因子，在细胞壁完整性（CWI）的调节中，菌核病菌核病的形成和致病性，是全球重要的植物病原真菌。SsStuA缺陷导致SsSmk3磷酸化水平异常，UDP-GlcNAc合成的关键基因SsAGM1无法响应细胞壁胁迫，对戊唑醇的耐受性下降。此外,ΔSsStuA不能形成菌核，但产生了更多的复合压疮。然而，由于侵入性菌丝生长不足和对过氧化氢的敏感性增加，ΔSsStuA的毒力显着降低。我们还发现SsStuA可以与过氧化氢酶家族基因的启动子结合，从而调节过氧化氢酶基因的表达。此外，在ΔSsStuA中发现活性氧（ROS）积累水平增加。总之,SsStua,作为参与CWI途径和ROS反应的核心转录因子，是营养生长所必需的，菌核形成,菌核菌的杀菌剂耐受性和全毒力。
