C端信号序列促进了Mycobacterium结核病病毒性因子的分泌
Patricia A Digiuseppe Champion1, Sarah A Stanley, Matthew M Champion
1Department of Microbiology and Immunology, University of California, San Francisco, 600 16th Street, Campus Box 2200, San Francisco, CA 94143-2200, USA.
概括
结核菌使用ESX-1分泌系统感染巨细胞. 研究人员在CFP-10上发现了一种特定的信号,该信号对ESX-1分泌至关重要,这证明了该信号是可移植的.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 免疫学 免疫学 免疫学
背景情况:
- 结核菌菌的感染依赖于ESX-1/Snm分泌系统的毒性.
- 精确的ESX-1分泌机制在很大程度上是未知的.
- ESX-1将关键的毒性因素传递到宿主巨细胞中.
研究的目的:
- 为了阐明Mycobacterium结核病中ESX-1分泌的机制.
- 识别ESX-1介导蛋白质运输中涉及的特定信号和组件.
主要方法:
- 研究了CFP-10基质和细胞质ESX-1成分 (Rv3871,Rv3870) 之间的相互作用.
- 利用点突变来破坏CFP-10与Rv3871.1的结合.
- 在突变条件下评估CFP-10/ESAT-6复合物的分泌.
- 通过将其连接到酵母菌ubiquitin来测试已识别的ESX-1信号的可移植性.
主要成果:
- 鉴定出CFP-10的非结构化的C终端是Rv3871.1.的识别信号.
- 干扰CFP-10与Rv3871的结合,取消了CFP-10/ESAT-6复合物的分泌.
- 鉴定到的ESX-1信号被证明是可移植的,当它与异质蛋白 (酵母无素) 连接时就能起作用.
结论:
- 在CFP-10基板内描述了一种新型的便携式分泌信号.
- 这种信号被Rv3871识别,Rv3871是ESX-1分泌机制的细胞质成分.
- 了解这种机制可以了解Mycobacterium结核病的毒性和潜在的治疗点.
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