PDF(Pubmed)
Abstract：
During a plant viral infection, host-pathogen interactions are critical for successful replication and propagation of the virus through the plant. RNA silencing suppressors (RSSs) are key players of this interplay, and they often interact with different host proteins, developing multiple functions. In the Potyviridae family, viruses produce two main RSSs, HCPro and type B P1 proteins. We focused our efforts on the less known P1b of cucumber vein yellowing virus (CVYV), a type B P1 protein, to try to identify possible factors that could play a relevant role during viral infection. We used a chimeric expression system based on plum pox virus (PPV) encoding a tagged CVYV P1b in place of the canonical HCPro. We used that tag to purify P1b in Nicotiana-benthamiana-infected plants and identified by mass spectrometry an importin-β-like protein similar to importin 7 of Arabidopsis thaliana. We further confirmed the interaction by bimolecular fluorescence complementation assays and defined its nuclear localization in the cell. Further analyses showed a possible role of this N. benthamiana homolog of Importin 7 as a modulator of the RNA silencing suppression activity of P1b.
摘要：
在植物病毒感染期间，宿主-病原体相互作用对于病毒通过植物成功复制和繁殖至关重要。RNA沉默抑制因子(RSSs)是这种相互作用的关键参与者，它们经常与不同的宿主蛋白相互作用，开发多种功能。在Potyviridae家族中，病毒产生两个主要的RSS，HCPro和B型P1蛋白。我们将精力集中在鲜为人知的黄瓜脉黄化病毒（CVYV）的P1b上，B型P1蛋白，试图找出在病毒感染过程中可能起相关作用的可能因素。我们使用了基于李子痘病毒（PPV）的嵌合表达系统，该系统编码带标签的CVYVP1b代替了规范的HCPro。我们使用该标签纯化了受烟草感染的植物中的P1b，并通过质谱鉴定了与拟南芥的importin7相似的importin-β-like蛋白。我们通过双分子荧光互补测定进一步证实了相互作用，并确定了其在细胞中的核定位。进一步的分析显示了Importin7的这种N.benthamiana同源物作为P1b的RNA沉默抑制活性的调节剂的可能作用。
