结构上不同的细菌TBC样GAPs将Arf GTPase与Rab1无活化联系起来,以抵消宿主防御
Na Dong1, Yongqun Zhu, Qiuhe Lu
1National Institute of Biological Sciences, Beijing 102206, China.
Cell
|September 4, 2012
概括
细菌蛋白 VirA 和 EspG 禁用 Rab1,破坏宿主细胞的运输和防御机制. 这一发现揭示了新的细菌策略来逃避宿主免疫力,并为Rab GTPase调节提供了洞察力.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 结构生物学 结构生物学
背景情况:
- 拉布GTPases调节细胞内贩运,并被细菌病原体所准.
- 了解细菌效应蛋白对于破译宿主-病原体相互作用至关重要.
研究的目的:
- 调查细菌效应剂Vira和EspG.的Rab GTPase激活蛋白 (RabGAP) 活动.
- 阐明这些效应因子对Rab1无活化的结构基础和功能后果.
主要方法:
- 生物化学试验测量RabGAP活动.
- 对效应器-Rab1复合体的晶体结构的确定.
- 对宿主细胞贩运和免疫反应的分析.
主要成果:
- 维拉和EspG具有类似于TBC的RabGAP活性,使Rab1失活.
- 拉布1的失活破坏了ER-Golgi的流通,并阻断了互白素-8的分泌.
- 结构分析揭示了明显的TBC类域和一种致病信号复合体.
结论:
- 病毒A和EspG使用类似于TBC的RabGAP域来操纵宿主Rab GTPases,以促进细菌的生存和发病.
- 这些发现表明,类似于TBC的RabGAP因子在细菌逃避策略中起着更广泛的作用.
相关概念视频
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