麻疹病毒转录的结构基础:疫苗RNA聚合酶复合物
Clemens Grimm1, Hauke S Hillen2, Kristina Bedenk1
1Department of Biochemistry and Cancer Therapy Research Center (CTRC), Theodor Boveri-Institute, University of Würzburg, Am Hubland, 97074 Würzburg, Germany.
Cell
|December 14, 2019
概括
化EM结构显示了疫苗病毒RNA聚合酶 (vRNAP) 和其转录因子. 这些发现阐明了宿主细胞内病毒基因表达和RNA处理的机制.
科学领域:
- 结构生物学
- 病毒学
- 分子生物学
背景情况:
- 脊髓灰质炎病毒在宿主细胞质中使用独特的DNA依赖RNA聚合酶 (vRNAP).
- 了解vRNAP结构对于破译病毒转录和RNA处理机制至关重要.
研究的目的:
- 确定 Vaccinia 病毒核心和完整的 RNA 聚合酶的高分辨率冷电子显微镜 (冷EM) 结构.
- 为vRNAP及其相关转录和mRNA处理因子的相互作用提供结构性见解.
主要方法:
- 使用冷电子显微镜 (cryo-EM) 解析了Vaccinia病毒vRNAP的结构.
- 实现的分辨率为2.8 Å,使酶复合体的详细可视化成为可能.
主要成果:
- 在2. 8 Å分辨率下确定了核心和完整的 Vaccinia 病毒 vRNAP 的冷 EM 结构.
- 这种vRNAP核心酶与真核RNA聚合酶II (Pol II) 有相似之处,但具有像转录因子Rap94这样的病毒特异性成分.
- 完整的vRNAP复合体包括转录因子 (VETF),mRNA处理因子 (VTF/CE,NPH-I),病毒蛋白E11和宿主tRNAGln,能够执行早期的转录周期.
- 结构分析显示了vRNAP组件 (Rap94,Rpo30,NPH-I) 和真核细胞因子 (TFIIB,TFIIS) 和染色体重塑剂之间的相似性.
结论:
- 确定的结构为了解天花病毒转录和RNA处理提供了详细的分子基础.
- 这些发现突显了vRNAP的复杂组合和功能适应,为病毒基因表达策略提供了洞察力.
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