高分辨率映射揭示了基因组插入和删除对RNA病毒进化的机制和贡献
Mauricio Aguilar Rangel1, Patrick T Dolan1,2, Shuhei Taguwa1,3
1Department of Biology, Stanford University, Stanford, CA 94305.
概括
RNA病毒通过插入和删除 (indels) 迅速进化,由RNA依赖RNA聚合酶 (RdRps) 驱动. 我们的研究揭示了这些indels是如何塑造病毒进化和健康的.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 进化遗传学 进化遗传学
背景情况:
- 由于依赖RNA的RNA聚合酶 (RdRps),RNA病毒具有很高的突变率.
- 插入和删除 (indels) 是病毒进化的关键驱动因素,但研究不足.
- 对于病毒适应性研究来说,了解印的形成和动态是至关重要的.
研究的目的:
- 描述RNA病毒中内核形成和进化动态的机制细节.
- 量化indel生成率并绘制它们的基因组分布图.
- 为了研究聚合酶忠实性,重组和indel生成之间的相互作用.
主要方法:
- 开发了一种混合实验生物信息方法 (MultiMatch),用于超深度测序分析.
- 提取了低频的indels以绘制它们的分布和量化速度.
- 研究了适应脊髓灰质炎病毒和登革热病毒种群,包括脊髓灰质炎病毒RdRp变种.
主要成果:
- 量化了工业发电率和确定了塑造工业多样性的约束因素.
- 在依赖RNA的RNA聚合酶忠实性和indel生成之间证明了权衡.
- 展示了转化框架和RNA结构限制了indel景观,施加了有害的负载.
- 识别了积极选择的indels调节RNA结构并产生新的蛋白质变体或有缺陷的干扰基因组.
结论:
- 在错误整合,重组和分离率之间建立了动力和机械的权衡.
- 揭示了在病毒进化,出现和感染调节中控制indels作用的功能原则.
- 突出了indels在病毒适应中的双重作用:为突变负载做出贡献和推动进化新性.
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