利用细菌效应蛋白来发现进化保存的抗病毒宿主机器
Aaron Embry1, Nina S Baggett1, David B Heisler1
1Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas, United State of America.
PLoS pathogens
|May 16, 2024
概括
研究人员利用细菌蛋白质发现了限制 arbovirus 复制的宿主因素. 他们确定SHOC2和PSMC1是古老的,保存的蛋白质,限制病毒在昆虫和人类中传播.
科学领域:
- 病毒学 病毒学
- 微生物学 微生物学
- 宿主-病原体相互作用
背景情况:
- 树冠病毒 (由关节动物传播的病毒) 是全球健康的重大威胁.
- 识别保存宿主因素对于理解树状病毒宿主范围和复制至关重要.
- 在类鸟细胞中自然流产的树冠病毒感染提供了一个独特的模型系统.
研究的目的:
- 发现进化保存的宿主因子,限制 arbovirus 复制.
- 利用细菌效应蛋白作为分子工具来识别这些宿主因素.
- 研究细菌效应者克服宿主限制的机制.
主要方法:
- 从七种病原体中选出210种细菌效应蛋白,在类鸟细胞中对抗四种树状病毒.
- 识别了拯救 arbovirus 复制的效应因子.
- 描述了Shigella flexneri IpaH4.4的E3泛素结合酶活性.
- 评估SHOC2和PSMC1枯竭对昆虫和人类细胞中的树冠病毒复制的影响.
主要成果:
- 鉴定了几种促进所有四种测试的树木病毒复制的细菌效应因子.
- 这些效应体具有各种不同的酶活性,对于打破 arbovirus 限制至关重要.
- 石格拉柔性菌IpaH4,一种E3泛素连酶,降解了保存的宿主蛋白SHOC2和PSMC1.
- SHOC2或PSMC1的耗尽增强了昆虫和人类细胞中的树冠病毒复制.
结论:
- 细菌效应器可以有效地用于发现保存的宿主抗病毒机制.
- SHOC2和PSMC1是古老的,保存的病毒限制因素,在不同的宿主中很重要.
- 这项研究揭示了SHOC2和PSMC1在抗病毒防御中的新型效应因子功能和保存作用.
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