核酸模拟抑制剂的结构基础和合理设计 逃避SARS-CoV-2校对酶
Junbo Wang1, Yufan Pan2, Yixiao Liu1
1MOE Key Laboratory of Protein Science, School of Medicine, Tsinghua University, Beijing 100084, China.
Journal of the American Chemical Society
|June 13, 2025
概括
核酸类似物 (NA) 可以逃避SARS-CoV-2 nsp14外核酶 (ExoN) 的分裂. 对NA的基和核糖部分的修改是逃避nsp14 ExoN活性的关键,为抗病毒药物设计提供了信息.
科学领域:
- 病毒学
- 分子生物学
- 药物发现
背景情况:
- 冠状病毒 (CoV) 使用外核糖酶 (nsp14 ExoN) 来校对新生RNA,切除不匹配的核酸或核酸类型 (NA).
- 了解NA如何逃避校对机制对于开发有效的抗病毒疗法至关重要.
研究的目的:
- 研究 SARS-CoV-2 nsp14 ExoN 分裂被特定的核酸类似物 (NA) 规避的机制.
- 鉴定能对nsp14 ExoN活动产生抗性的NA的结构特征.
- 引导新型抗冠状病毒NA的合理设计.
主要方法:
- 使用化学合成的RNA,在3'端包含各种NA.
- 评估了SARS-CoV-2 nsp14 ExoN在这些改性RNA上的分裂活性.
- 确定了与NA结合RNA的nsp10/14复合物的冷电子显微镜结构.
- 对nsp14 ExoN中的关键残留物进行突变发生研究.
主要成果:
- 与天然核酸或其他测试的NA相比,Nsp14 ExoN对含有索福斯布维尔单酸盐 (SMP) 和AT-9010单酸盐 (ATMP) 的RNA活性显著降低.
- 低温-EM结构和突变发生表明H95,Q145和F146残留物对于识别基团和定位NAs进行裂变至关重要.
- 通过非相互作用基和化学修饰的核糖的组合,NAs避免了裂变.
结论:
- 通过NAs逃避nsp14 ExoN裂变取决于特定的基核酸相互作用和核糖修饰.
- 基于这些发现,设计了两种新的NA,它们对nsp14 ExoN裂变具有抗性.
- 这些见解对于下一代抗冠状病毒核酸类药物的合理设计是有价值的.
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