Vm‐milR37 contributes to pathogenicity by regulating glutathione peroxidase gene VmGP in Valsa mali. (5th December 2020)

• Record Type: Journal Article
• Authors: Feng, Hao; Xu, Ming; Gao, Yuqi; Liang, Jiahao; Guo, Feiran; Guo, Yan; Huang, Lili
• Is Part Of: Molecular plant pathology. Volume 22:Number 2(2021)
• Page Start: 243
• Page End: 254
• Publication Date: 2020-12-05
• Subjects: apple tree -- microRNA‐like RNA -- oxidative stress -- posttranscriptional regulation virulence Valsa canker; Plant diseases -- Molecular aspects -- Periodicals; Plant-pathogen relationships -- Molecular aspects -- Periodicals; 571.936
• DOI: 10.1111/mpp.13023
• Languages: English
• ISSNs: 1464-6722

Abstract

Abstract: MicroRNAs play important roles in various biological processes by regulating their corresponding target genes. However, the function and regulatory mechanism of fungal microRNA‐like RNAs (milRNAs) are still largely unknown. In this study, a milRNA ( Vm‐ milR37) was isolated and identified from Valsa mali, which causes the most serious disease on the trunk of apple trees in China. Based on the results of deep sequencing and quantitative reverse transcription PCR, Vm‐ milR37 was found to be expressed in the mycelium, while it was not expressed during the V. mali infection process. Overexpression of Vm‐ milR37 did not affect vegetative growth, but significantly decreased pathogenicity. Based on degradome sequencing, the target of Vm‐ milR37 was identified as VmGP, a glutathione peroxidase. The expression of Vm‐ milR37 and VmGP showed a divergent trend in V. mali– apple interaction samples and Vm‐ milR37 overexpression transformants. The expression of VmGP could be suppressed significantly by Vm‐ milR37 when coexpressed in tobacco leaves. Deletion of VmGP showed significantly reduced pathogenicity compared with the wild type. VmGP deletion mutants showed more sensitivity to hydrogen peroxide. Apple leaves inoculated with Vm ‐milR37 overexpression transformants and VmGP deletion mutant displayed increased accumulation of reactive oxygen species compared with the wild type. Thus, Vm ‐milR37 plays a critical role in pathogenicity by regulating VmGP, which contributes to the oxidative stress response during V. mali infection. These results provide important evidence to define the roles of milRNAs and their corresponding target genes in pathogenicity. Abstract : This study demonstrates that a fungal milRNA Vm ‐milR37 contributes to pathogenicity by adaptively regulating the glutathione peroxidase gene ( VmGP ), which contributes to the oxidative stress response in Valsa mali .