Centre SÈVE, Département de Biologie, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada.
Mol Plant Microbe Interact. 2023 Jul;36(7):425-433. doi: 10.1094/MPMI-11-22-0224-R. Epub 2023 Aug 14.
During virus infection, Argonaute (AGO) proteins bind to Dicer-produced virus small interfering RNAs and target viral RNA based on sequence complementarity, thereby limiting virus proliferation. The AGO2 protein is important for resistance to multiple viruses, including potato virus X (PVX). In addition, AGO5 is important in systemic defense against PVX. Normally is expressed only in reproductive tissues, and its induction by virus infection is thought to be important for its participation in antiviral defense. However, it is unclear what mechanisms induce expression in response to virus infection. Here, we show that , a mutant compromised in jasmonic acid (JA) biosynthesis, displays constitutive upregulation of . This mutant also showed increased resistance to PVX and this resistance was dependent on a functional gene. Furthermore, methyl jasmonate treatment ablated expression in leaves during virus infection and resulted in increased susceptibility to virus. Our results further support a role for AGO5 in antiviral RNA silencing and a negative regulation by JA, a plant hormone associated with defense against plant-feeding arthropods, which are often the vectors of plant viruses. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
在病毒感染过程中，Argonaute (AGO) 蛋白结合 Dicer 产生的病毒小干扰 RNA，并根据序列互补性靶向病毒 RNA，从而限制病毒增殖。AGO2 蛋白对于抵抗多种病毒（包括马铃薯病毒 X（PVX））很重要。此外，AGO5 在针对 PVX 的全身防御中很重要。通常仅在生殖组织中表达，其被病毒感染诱导被认为对其参与抗病毒防御很重要。然而，尚不清楚哪些机制会诱导其在病毒感染时表达。在这里，我们表明，突变体在茉莉酸（JA）生物合成中受到损害，表现出 的组成性上调。该突变体还表现出对 PVX 的抗性增加，并且这种抗性依赖于功能正常的 基因。此外，茉莉酸甲酯处理在病毒感染期间消除了叶片中的 表达，并导致对病毒的易感性增加。我们的结果进一步支持了 AGO5 在抗病毒 RNA 沉默中的作用，以及 JA 的负调控作用，JA 是一种与防御以植物为食的节肢动物相关的植物激素，而这些节肢动物通常是植物病毒的载体。[公式：见正文]版权所有©2023 作者。这是一个在 CC BY-NC-ND 4.0 国际许可下发布的开放获取文章。
