Anhui Provincial Key Laboratory of the Conservation and Exploitation of Biological Resources/College of Life Sciences, Anhui Normal University, Wuhu, Anhui 241000, China.
National Education Minister Key Laboratory of Plant Genetic Improvement and Comprehensive Utilization/College of Agriculture, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China.
Mol Plant Microbe Interact. 2022 Jun;35(6):440-449. doi: 10.1094/MPMI-12-21-0295-R. Epub 2022 Apr 26.
is a broad-host range oomycete pathogen that can cause severe phytophthora blight disease of pepper and hundreds of other plant species worldwide. Natural resistance against is inadequate, and it is very difficult to control by most of existing chemical fungicides. Therefore, it is urgent to develop alternative strategies to control this pathogen. Recently, host-induced or spray-induced gene silencing of essential or virulent pathogen genes provided an effective strategy for disease controls. Here, we demonstrate that can effectively take up small interfering RNAs (siRNAs) from the environment. According to RNA-seq and quantitative reverse transcription PCR analysis, we identified four RXLR effector genes that are significantly up-regulated during the infection stage. Transient overexpression and promote-infection assays indicated that RXLR1 and RXLR4 could promote pathogen infection. Using a virus-induced gene silencing system in pepper plants, we found that in planta-expressing RNA interference (RNAi) constructs that target or could significantly reduce pathogen infection, while co-interfering and could confer a more enhanced resistance to . We also found that exogenously applying siRNAs that target or could restrict growth of on the pepper and leaves; when targeting and simultaneously, the control effect was more remarkable. These data suggested that RNAi-based gene silencing of RXLR effectors has great potential for application in crop improvement against and also provides an important basis for the development of RNA-based antioomycete agents.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
是一种广泛宿主范围的卵菌病原体，可导致辣椒和全球数百种其他植物物种的严重疫霉枯萎病。对 的天然抗性不足，而且大多数现有化学杀菌剂很难控制。因此，迫切需要开发替代策略来控制这种病原体。最近，必需或毒力病原体基因的宿主诱导或喷雾诱导基因沉默为疾病控制提供了一种有效策略。在这里，我们证明 可以有效地从环境中摄取小干扰 RNA (siRNA)。根据 RNA-seq 和定量反转录 PCR 分析，我们鉴定了四个在感染阶段显著上调的 RXLR 效应子基因。瞬时过表达和促进感染测定表明，RXLR1 和 RXLR4 可以促进病原体感染。使用辣椒植物中的病毒诱导基因沉默系统，我们发现，在植物中表达靶向 或 的 RNA 干扰 (RNAi) 构建体可以显著降低病原体感染，而同时干扰 和 可以赋予对 的更强抗性。我们还发现，靶向 或 的外源施用 siRNA 可以限制 在辣椒和 叶片上的生长；当同时靶向 和 时，控制效果更加显著。这些数据表明，基于 RNAi 的 RXLR 效应子基因沉默在作物改良方面具有很大的潜力，可以对抗 和 ，也为基于 RNA 的抗卵菌剂的开发提供了重要基础。
