The phloem-feeding insect Bemisia tabaci is an important pest, responsible for the transmission of several crop-threatening virus species. While feeding, the insect secretes a cocktail of effectors to modulate plant defense responses. Here, we present a set of proteins identified in an artificial diet on which B. tabaci was salivating. We subsequently studied whether these candidate effectors can play a role in plant immune suppression. Effector G4 was the most robust suppressor of an induced- reactive oxygen species (ROS) response in Nicotiana benthamiana. In addition, G4 was able to suppress ROS production in Solanum lycopersicum (tomato) and Capsicum annuum (pepper). G4 localized predominantly in the endoplasmic reticulum in N. benthamiana leaves and colocalized with two identified target proteins in tomato: REF-like stress related protein 1 (RSP1) and meloidogyne-induced giant cell protein DB141 (MIPDB141). Silencing of MIPDB141 in tomato reduced whitefly fecundity up to 40%, demonstrating that the protein is involved in susceptibility to B. tabaci. Together, our data demonstrate that effector G4 impairs tomato immunity to whiteflies by interfering with ROS production and via an interaction with tomato susceptibility protein MIPDB141.

Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

以韧皮部为食的昆虫烟粉虱是一种重要的害虫，负责传播几种威胁作物的病毒种类。在进食时，昆虫会分泌多种效应物来调节植物的防御反应。在这里，我们展示了在烟粉虱分泌唾液的人工饮食中鉴定出的一组蛋白质。我们随后研究了这些候选效应子是否可以在植物免疫抑制中发挥作用。效应器 G4 是本塞姆氏烟草中诱导活性氧 (ROS) 反应最强大的抑制因子。此外，G4 能够抑制Solanum lycopersicum（番茄）和Capsicum annuum（胡椒）中 ROS 的产生。 G4 主要定位于本塞姆氏烟草叶子的内质网中，并与番茄中两个已鉴定的靶蛋白共定位：REF 样应激相关蛋白 1 (RSP1) 和根结线虫诱导的巨细胞蛋白 DB141 (MIPDB141)。番茄中MIPDB141的沉默使烟粉虱的繁殖力降低高达 40%，表明该蛋白与烟粉虱的易感性有关。总之，我们的数据表明，效应器 G4 通过干扰 ROS 产生以及与番茄易感蛋白 MIPDB141 的相互作用，损害番茄对粉虱的免疫力。

版权所有 © 2024 作者。这是一篇根据 CC BY-NC-ND 4.0 国际许可证分发的开放获取文章。