背景回顾：Virus-derived small interference RNAs (vsiRNAs) can not only suppress virus infection in plant via induction of RNA silencing but also enhance virus infection via regulation of host defensive gene expressions. 

提出问题：The underlying mechanism(s) controlling the vsiRNA-mediated host immunity or susceptibility remain largely unknown.

研究材料：In this study, we prepared several transgenic wheat lines using four artificial microRNA expression vectors carrying vsiRNAs from Wheat yellow mosaic virus (WYMV) RNA1. 

结果1-转amiRNA1小麦具抗性：Laboratory and field tests showed that two transgenic wheat lines expressing amiRNA1 were highly resistant to WYMVinfection. 

结果2-amiRNA1抑制ROS清除基因TaAAED1：Further analyses showed that vsiRNA1 could modulate the expression of a wheat thioredoxin-like (TaAAED1) gene, a negative regulator of reactive oxygen species (ROS) production in chloroplast. 

结果3-剂量效应：The function of TaAAED1 in ROS scavenging could be suppressed by vsiRNA1 in a dose-dependent manner. 

结果4-广谱抗性：In addition, transgenic expression of amiRNA1 in wheat results in a broad-spectrum disease resistance to Chinese wheat mosaic virus, Barley stripe mosaic virus, and Puccinia striiformis f. sp. tritici infection, suggesting that vsiRNA1 is involved in wheat immunity via ROS signal. 

结论：Collectively, these findings reveal a previously unidentified mechanism underlying the arm-race between viruses and plants.

 摘 要 

源自病毒的小干扰RNA（vsiRNA）不仅能够通过RNA沉默在植物中抑制病毒的侵染，还会通过调控寄主防御基因的表达增强病毒的侵染。但是，vsiRNA介导的寄主植物免疫或是易感分子机制还不清楚。本文中，作者利用四种携带小麦黄花叶病病毒RNA1的人工microRNA表达载体，构建了几个转基因株系。实验室和大田条件测试均显示，两个表达amiRNA1的小麦株系均对小麦黄花叶病病毒产生了抗性。进一步的分析显示vsiRNA1能够改变小麦中类硫氧还蛋白编码基因TaAAED1的表达，而该基因是叶绿体中活性氧物质（ROS）产生的一个负调控因子。vsiRNA1对于TaAAED1基因的ROS清除功能的抑制存在剂量效应。另外，小麦转基因株系中amiRNA1的表达会导致植株对中国小麦花叶病毒、大麦条纹花叶病毒和小麦条锈菌侵染的广谱抗性，说明vsiRNA1通过ROS信号参与小麦免疫。综上，本文的研究结果揭示了一个先前未知的植物与病毒之间的“军备竞赛”潜在机制。