Prakash Ved, Nihranz Chad T, Casteel Clare L
Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Sciences, Cornell University, Ithaca, NY, U.S.A.
Mol Plant Microbe Interact. 2023 Mar;36(3):189-197. doi: 10.1094/MPMI-09-22-0183-R. Epub 2023 Mar 7.
Virus infection can increase drought tolerance of infected plants compared with noninfected plants; however, the mechanisms mediating virus-induced drought tolerance remain unclear. In this study, we demonstrate turnip mosaic virus (TuMV) infection increases survival under drought compared with uninfected plants. To determine if specific TuMV proteins mediate drought tolerance, we cloned the coding sequence for each of the major viral proteins and generated transgenic that constitutively express each protein. Three TuMV proteins, 6K1, 6K2, and NIa-Pro, enhanced drought tolerance of when expressed constitutively in plants compared with controls. While in the control plant, transcripts related to abscisic acid (ABA) biosynthesis and ABA levels were induced under drought, there were no changes in ABA or related transcripts in plants expressing 6K2 under drought compared with well-watered conditions. Expression of 6K2 also conveyed drought tolerance in another host plant, , when expressed using a virus overexpression construct. In contrast to ABA, 6K2 expression enhanced salicylic acid (SA) accumulation in both and . These results suggest 6K2-induced drought tolerance is mediated through increased SA levels and SA-dependent induction of plant secondary metabolites, osmolytes, and antioxidants that convey drought tolerance. [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.
与未感染的植物相比，病毒感染可提高受感染植物的耐旱性；然而，介导病毒诱导的耐旱性的机制仍不清楚。在本研究中，我们证明与未感染的植物相比，芜菁花叶病毒（TuMV）感染可提高干旱条件下的存活率。为了确定是否特定的TuMV蛋白介导耐旱性，我们克隆了每种主要病毒蛋白的编码序列，并生成了组成型表达每种蛋白的转基因植株。与对照相比，三种TuMV蛋白6K1、6K2和NIa-Pro在植物中组成型表达时增强了耐旱性。在对照植物中，与脱落酸（ABA）生物合成相关的转录本和ABA水平在干旱条件下被诱导，而与水分充足条件相比，在干旱条件下表达6K2的植物中ABA或相关转录本没有变化。当使用病毒过表达构建体表达时，6K2的表达在另一种寄主植物中也赋予了耐旱性。与ABA相反，6K2的表达增强了烟草和本氏烟草中水杨酸（SA）的积累。这些结果表明，6K2诱导的耐旱性是通过增加SA水平以及SA依赖诱导的植物次生代谢产物、渗透调节物质和抗氧化剂来介导的，这些物质赋予了耐旱性。[公式：见正文] 版权所有© 2023作者。这是一篇根据知识共享署名 - 非商业性使用 - 禁止演绎4.0国际许可协议分发的开放获取文章。
