菌体转录因子取代宿主σ因子并稳定其自己的σ因子
Liqiao Xu1,2, Liang Liang1,2, Linggang Yuan1,2
1Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310001, China.
Nucleic acids research
|July 19, 2025
概括
菌体蛋白Gp79通过取代宿主西格玛因子并使菌体特异性转录成为可能,独特地控制细菌转录. 这揭示了菌体基因调节的新机制和潜在的合成生物学应用.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 细菌转录依赖于RNA聚合酶 (RNAP) 与西格玛 (σ) 因子相互作用.
- 菌体,丰富的生物实体,拥有复杂的转录调节机制.
- 在转录水平上了解菌体与宿主相互作用,可以了解细菌的基因表达.
研究的目的:
- 阐明埃舍里希亚大肠杆菌菌体phiEco32的菌蛋白Gp79在转录中表现出双重调控作用的机制.
- 确定Gp79介导的宿主转录抑制和菌体转录激活的结构基础.
- 为了研究Gp79,其相关的西格玛因子 (gp36) 和细菌RNAP之间的相互作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定高分辨率结构.
- 生物化学分析以验证结构发现和功能作用.
- 对RNAP-Gp79和RNAP-Gp79-Gp36促进体复合物的结构研究.
主要成果:
- 冷-EM结构揭示了Gp79的N端如何侵入RNAPRNA通道,取代宿主 σ70因子.
- 在与gp36相互作用时,gp79经历了形状变化,稳定了RNAP促进器开放复合体.
- 结构和生化数据阐明了 σ 位移和促进体识别的独特机制.
结论:
- Gp79充当分子开关,抑制宿主转录,促进菌体转录.
- 这些发现提供了对菌体特异性转录调节的机制性理解.
- 这项工作对理解菌体生物学和开发合成生物学工具有意义.
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