Grapevine comparative early transcriptome profiling reveals that Flavescence dorée phytoplasma represses plant responses induced by vector feeding in susceptible varieties

Flavescence dorée is the most serious grapevine yellows disease in Europe. It is caused by phytoplasmas which are transmitted from grapevine to grapevine by the leafhopper Scaphoideus titanus. Differences in susceptibility among grapevine varieties suggest the existence of specific genetic features associated with resistance to the phytoplasma and/or possibly with its vector. In this work, RNA-Seq was used to compare early transcriptional changes occurring during the three-trophic interaction between the phytoplasma, its vector and the grapevine, represented by two different cultivars, one very susceptible to the disease and the other scarcely susceptible. Background: Flavescence dorée is the most serious grapevine yellows disease in Europe. It is caused by phytoplasmas which are transmitted from grapevine to grapevine by the leafhopper Scaphoideus titanus. Differences in susceptibility among grapevine varieties suggest the existence of specific genetic features associated with resistance to the phytoplasma and/or possibly with its vector. In this work, RNA-Seq was used to compare early transcriptional changes occurring during the three-trophic interaction between the phytoplasma, its vector and the grapevine, represented by two different cultivars, one very susceptible to the disease and the other scarcely susceptible. The comparison of the transcriptomic responses highlighted both passive and active defense mechanisms against the vector and/or the pathogen in the scarcely-susceptible variety, as well as the capacity of the phytoplasmas to repress the defense reaction against the insect in the susceptible variety.

金黄化病（Flavescence dorée）是欧洲最为严重的葡萄黄化类病害。该病害由植原体（phytoplasma）引发，植原体通过凹缘菱纹叶蝉（Scaphoideus titanus）在葡萄植株间进行传播。不同葡萄品种对该病害的感病性存在差异，这表明存在与抗植原体、或与抗其传毒媒介相关的特异性遗传特征。本研究利用RNA测序（RNA-Seq）技术，对比两种不同葡萄栽培品种在植原体、其传毒媒介与葡萄构成的三营养级互作过程中发生的早期转录变化——其中一个品种对该病害高度感病，另一个则几乎不感病。
背景：金黄化病（Flavescence dorée）是欧洲最为严重的葡萄黄化类病害。该病害由植原体（phytoplasma）引发，植原体通过凹缘菱纹叶蝉（Scaphoideus titanus）在葡萄植株间进行传播。不同葡萄品种对该病害的感病性存在差异，这表明存在与抗植原体、或与抗其传毒媒介相关的特异性遗传特征。本研究利用RNA测序（RNA-Seq）技术，对比两种不同葡萄栽培品种在植原体、其传毒媒介与葡萄构成的三营养级互作过程中发生的早期转录变化——其中一个品种对该病害高度感病，另一个则几乎不感病。
转录组响应的对比分析显示，在低感病品种中，存在针对传毒媒介与/或病原菌的被动与主动防御机制；同时在感病品种中，植原体具备抑制宿主对昆虫媒介的防御反应的能力。