阿拉比多普西斯eIF4E1在TuMV感染期间保护转化机制,并限制病毒积累
Delyan Zafirov1,2, Nathalie Giovinazzo1, Cécile Lecampion2
1GAFL, INRAE, Montfavet, France.
PLoS pathogens
|November 20, 2023
概括
病毒感染依赖于劫持翻译启动因子eIF4E. 保持eIF4E1功能对于植物健康和有效的病毒耐药性至关重要,因为它缺少可以损害植物并帮助某些病毒感染.
科学领域:
- 植物病毒学 植物病毒学
- 分子植物病原体相互作用
- 植物分子生物学 植物分子生物学
背景情况:
- 植物病毒的主要群体之一的病毒依赖宿主转化启动因子,特别是真核生物启动因子4E (eIF4E),以成功感染.
- 植物的自然耐药性通常涉及eIF4E多态,可以防止病毒劫持,同时保持基本的翻译功能.
- 已经探索了eIF4E的遗传失活化,以设计抗性病毒,但存在对植物健康和耐药性有效性的潜在负面影响的担忧.
研究的目的:
- 调查eIF4E失活对植物健康和病毒耐药效率的不良影响.
- 阐明Arabidopsis eIF4E1在植物转化中的特定作用及其与不同病毒的相互作用,特别是卜马赛克病毒 (TuMV).
- 了解病毒感染期间与eIF4E功能相关的潜在敏感性或耐药性的分子机制.
主要方法:
- 研究阿拉比多普西斯eIF4E1在对病毒感染的反应中的作用,特别是TuMV.
- 分析全球植物转化率和野生类型和eIF4E1缺乏植物中的病毒积累.
- 调查eIF4E1缺失对其他转化因子 (如eIFiso4G1.1) 的产生和功能的影响.
- 在不同的eIF4E1遗传背景下评估植物适应性和病毒积累.
主要成果:
- eIF4E1对于保持全球植物转换和限制TuMV积累至关重要.
- 缺少eIF4E1导致转移,有利于病毒繁殖而不是宿主转化.
- 在eIF4E1缺乏植物的TuMV感染导致截断的eIFiso4G1蛋白.
- eIFiso4G1在TuMV积累中发挥作用,并在感染期间支持植物健康.
结论:
- eIF4E1积极应对TuMV劫持工厂翻译机械的行为.
- 保持像eIF4E这样的翻译启动因子的功能对于强大的病毒耐药性策略至关重要.
- 旨在通过eIF4E操纵实现病毒耐药性的策略必须考虑这些因素在病毒感染和重要植物过程中的双重作用.
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