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Updated: Jun 17, 2025

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通过RfaH介导的转录-翻译合的结构基础

Vadim Molodtsov^1,2, Chengyuan Wang^1,3, Jing Zhang³

¹Waksman Institute and Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, USA.

Nature structural & molecular biology

|August 8, 2024

概括

细菌蛋白RfaH在转录-翻译合过程中将RNA聚合酶 (RNAP) 与核糖体结合起来. 它的结构比它的对应NusG更多地限制了运动,揭示了RfaH在DNA ops网站上的功能.

科学领域:

分子生物学分子生物学
结构生物学结构生物学
微生物学微生物学

背景情况:

转录-翻译合对于细菌基因表达是必不可少的.
蛋白质RfaH是NusG的一种类型,它在特定的DNA部位 (称为Ops部位) 促进了这一过程.
RfaH暂停RNA聚合酶 (RNAP) 并加载到它上,影响基因表达.

研究的目的:

确定涉及RfaH的转录-翻译复合体 (TTC) 的结构组织.
阐明RfaH调解转录-翻译合的机制.
将RfaH合TTC的结构和功能方面与涉及NusG的TTC进行比较.

主要方法:

低温电子显微镜 (cryo-EM) 用于在TTC中可视化Escherichia coli RfaH.
结构分析的重点是RfaH,RNAP和核糖体之间的相互作用.
对RfaH和NusG结合的TTC进行比较,以评估灵活性和组织方面的差异.

主要成果:

低温-EM结构显示RfaH通过其N端和C端域分别桥接RNAP和核糖体.
与NusG结合的TTC相比,与RfaH结合的TTC由于链接器的灵活性而表现出更受限制的RNAP-核糖体定位.
与RfaH合的TTC的结构组织在作战地点的"装载"和"装载"状态中是一致的.

结论:

该研究定义了RfaH介导的转录-翻译合的结构基础.
RfaH的独特结构特征决定了RNAP和核糖体之间的更受约束的相互作用.
这些发现为了解RfaH在翻译启动和基因调节中的作用提供了基础.

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