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莱吉欧内拉肺 SidD是一种修改Rab1的deAMPylase
1Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907, USA.
Nature
|July 8, 2011
概括
肺炎病毒使用SidD逆转SidM的作用,SidM是一种锁定Rab1在活性状态的细菌蛋白质. 这种deAMPylation对于在感染期间从细胞中释放Rab1至关重要.
科学领域:
- 微生物学 微生物学
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
背景情况:
- 肺炎杆菌操纵宿主囊泡的贩运,以进行细胞内生长.
- 在Dot/Icm类型IV分泌系统 (T4SS) 输送效应蛋白到宿主细胞.
- 作用因子SidM/DrrA通过关氨酸核酸交换和AMPylation激活小GTPase Rab1.
研究的目的:
- 为了研究L. pneumophila蛋白SidD.的功能.
- 为了确定SidD是否与Rab1.1相互作用或修改Rab1.
- 为了阐明Rab1修饰在L. pneumophila感染中的作用.
主要方法:
- 生物化学试验测试SidD在Rab1.1上的deAMPylation活性.
- 基于酵母的毒性测试来评估SidM和SidD的相互作用.
- 显微镜观察Rab1的局部化和释放.
主要成果:
- 鉴定出SidD是一种Rab1deAMPylase,它可以去除SidM介导的AMPylation.
- 在酵母中,SidD的deAMPylation活性抑制了SidM诱导的毒性.
- 对Rab1从细菌胞体的有效释放至关重要的是SidD活动.
结论:
- 建立了在L. pneumophila感染期间对Rab1活性进行时间控制的分子机制.
- 通过AMPylation介导的信号转导是一种由细菌酶调节的可逆过程.
- 在细菌病变过程中,SidD在调节宿主途径方面发挥着关键作用.
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