Key Laboratory of Forest Protection of National Forestry and Grassland Administration, Ecology and Nature Conservation Institute, Chinese Academy of Forestry, Beijing 100091, China.
Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China.
Phytopathology. 2024 Oct;114(10):2331-2340. doi: 10.1094/PHYTO-01-24-0026-R. Epub 2024 Sep 30.
(pine wood nematode, PWN), a migratory plant-parasitic nematode, acts as an etiological agent, inflicting considerable damage to pine forests worldwide. Plant immunity constitutes a crucial factor in resisting various pathogenic invasions. The primary defensive responses of host pines against PWN infection encompass terpene accumulation, defense response-related gene expression, and programmed cell death. Venom allergen-like proteins (VAPs), as potential effectors, are instrumental in facilitating the successful colonization of PWNs. In this study, we investigated the inhibition of VAP () expression by RNA interference in vitro. Following silencing, the reproduction rate and migration rate of the PWN population in decreased, the expression of the α-pinene synthase gene was induced, other terpene synthase and pathogenesis-related genes were inhibited and delayed, the peak times and levels of terpene-related substances were changed, and the degree of cavitation in was diminished. Transient expression of BxVAP1 in revealed that BxVAP1 was expressed in both the cell membrane and nucleus, inducing programmed cell death and the expression of pathogen-associated molecular pattern-triggered immunity marker genes ( and ). This study is the first to demonstrate that silencing the gene affects host defense responses, including terpenoid metabolism in , and that BxVAP1 can be recognized by as an effector to trigger its innate immunity, expanding our understanding of the parasitic mechanism of .
(松材线虫，PWN)，一种迁移性植物寄生线虫，作为病因，对世界各地的松林造成了相当大的破坏。植物免疫是抵抗各种病原入侵的关键因素。宿主松树对 PWN 感染的主要防御反应包括萜烯积累、防御反应相关基因表达和程序性细胞死亡。毒液过敏原样蛋白 (VAPs)，作为潜在的效应物，在促进 PWN 成功定殖方面发挥作用。在这项研究中，我们研究了 RNA 干扰体外抑制 VAP()表达。沉默后，PWN 种群在中的繁殖率和迁移率降低，α-蒎烯合酶基因的表达被诱导，其他萜烯合酶和发病相关基因被抑制和延迟，萜烯相关物质的峰值时间和水平发生变化，并且 中的空化程度降低。在 中瞬时表达 BxVAP1 表明 BxVAP1 在细胞膜和核中均有表达，诱导程序性细胞死亡和病原体相关分子模式触发免疫标记基因 (和) 的表达。这项研究首次表明，沉默基因会影响宿主防御反应，包括中萜烯代谢，并且 BxVAP1 可以被 识别为触发其先天免疫的效应物，扩展了我们对 的寄生机制的理解。
