Department of Entomology, Nematology and Chemistry units, Agricultural Research Organization (ARO), Volcani Center, Bet Dagan 50250, Israel.
Department of Plant Pathology and Microbiology, the Robert H. Smith Faculty of Agriculture, Food and Environment, the Hebrew University of Jerusalem, Rehovot 76100, Israel.
Mol Plant Microbe Interact. 2023 Feb;36(2):79-94. doi: 10.1094/MPMI-10-22-0212-R. Epub 2023 Jan 25.
During parasitism, root-knot nematode spp. inject molecules termed effectors that have multifunctional roles in construction and maintenance of nematode feeding sites. As an outcome of transcriptomic analysis of , we identified and characterized two differentially expressed genes encoding the predicted proteins MjShKT, carrying a toxin (ShKT) domain, and MjPUT3, carrying a ground-like domain, both expressed during nematode parasitism of the tomato plant. Fluorescence in-situ hybridization revealed expression of and in the dorsal esophageal glands, suggesting their injection into host cells. expression was upregulated during the parasitic life stages, to a maximum at the mature female stage, whereas expression increased in third- to fourth-stage juveniles. Subcellular in-planta localization of MjShKT and MjPUT3 using a fused fluorescence marker indicated MjShKT co-occurrence with the endoplasmic reticulum, the perinuclear endoplasmatic reticulum, and the Golgi organelle markers, while MjPUT3 localized, to some extent, within the endoplasmatic reticulum and was clearly observed within the nucleoplasm. MjShKT inhibited programmed cell death induced by overexpression of MAPKKKα and Gpa2/RBP-1. Overexpression of in tomato hairy roots allowed an increase in nematode reproduction, as indicated by the high number of eggs produced on roots overexpressing . Roots overexpressing were characterized by enhanced root growth, with no effect on nematode development on those roots. Investigation of the two candidate effectors suggested that MjShKT is mainly involved in manipulating the plant effector-triggered immune response toward establishment and maintenance of active feeding sites, whereas MjPUT3 might modulate roots morphology in favor of nematode fitness in the host roots. [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.
在寄生过程中，根结线虫属的 spp. 会注射多种功能的分子，称为效应子，这些分子在构建和维持线虫取食部位方面发挥作用。作为 的转录组分析的结果，我们鉴定和描述了两个差异表达的基因，它们编码预测的蛋白 MjShKT，携带毒素 (ShKT) 结构域，和 MjPUT3，携带地面样结构域，这两个基因都在番茄植物的线虫寄生过程中表达。荧光原位杂交显示 和 在背食管腺中的表达，表明它们被注射到宿主细胞中。 在寄生生活阶段的表达上调，在成熟雌虫阶段达到最大值，而 在第三至第四期幼虫阶段表达增加。使用融合荧光标记物在植物体内进行的 MjShKT 和 MjPUT3 的亚细胞定位表明，MjShKT 与内质网、核周内质网和高尔基体标记物共同存在，而 MjPUT3 在一定程度上定位于内质网内，并在核质内清晰可见。MjShKT 抑制了由 MAPKKKα 和 Gpa2/RBP-1 过表达诱导的程序性细胞死亡。 在番茄根毛中过表达 允许增加线虫繁殖，这可以通过在过表达 的根上产生的大量卵来指示。过表达 的根的特征是根生长增强，对这些根上的线虫发育没有影响。对这两个候选效应子的研究表明，MjShKT 主要参与操纵植物效应器触发的免疫反应，以建立和维持活跃的取食部位，而 MjPUT3 可能调节根形态，有利于线虫在宿主根中的适应性。 [公式：见正文] 版权所有 © 2023 作者。这是一个在 CC BY-NC-ND 4.0 国际许可下分发的开放获取文章。
