菌体卫星P4的Psu蛋白通过强制超寡合化抑制转录终结因子 ρ
Daniela Gjorgjevikj1,2, Naveen Kumar3, Bing Wang4
1Laboratory of Structural Biochemistry, Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany.
Nature communications
|January 9, 2025
概括
体蛋白Psu通过在开放状态下紧Rho环来抑制转录终结因子Rho. 这种机制揭示了一个普遍的细菌基因调节策略,涉及蛋白质寡合体状态的调节.
科学领域:
- 细菌生物学的生物学
- 转录调节的分子机制
- 蛋白质-DNA相互作用
背景情况:
- 菌体通常会操纵宿主转录以实现自身复制.
- 通过未知的机制,P4胞卫星蛋白Psu抑制了转录终结因子Rho.
- 罗因子是细菌转录终止所必需的六合蛋白质.
研究的目的:
- 阐明Psu抑制Rho功能的分子机制.
- 为了确定Rho-Psu相互作用的结构基础.
- 调查Rho-Psu相互作用的体内相关性及其在菌体与宿主相互作用中的作用.
主要方法:
- 低温电子显微镜 (cryo-EM) 用于确定Rho-Psu复合物的结构.
- 生物化学分析包括ATPase,核酸结合和核酸结合.
- 结构引导的突变发生结合细菌生长,下拉和转录终止测试.
- 生物信息分析以识别Psu同类物和相关系统.
主要成果:
- 低温-EM结构显示Psu二极体结合并稳定开放的,不活跃的六极体Rho环,促进更高的寡合体状态.
- 生物化学研究表明,PSU可以阻止Rho环的闭合,并将核酸困在Rho的结合口袋中.
- 在体内测试证实了特定Rho-Psu接口的功能重要性.
- 生物信息分析表明,PSU与Enterobacteriaceae中的各种菌体防御系统有关.
结论:
- Psu通过改变其寡合状态来抑制Rho,防止转录终止.
- 蛋白质寡合体状态的调节是细菌中广泛存在的基因调节原理.
- Psu与菌体防御系统的关联表明它在调节抗菌体基因表达中的作用.
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