基对分辨率揭示了聚类R循环和易受DNA损伤的R循环
Yaoyi Li1, Yingliang Sheng2, Chao Di3
1State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China; Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
Molecular cell
|March 20, 2025
概括
我们开发了RIAN-seq来映射R循环,揭示了它们在基因表达和基因组稳定中的双重作用. 这种新方法检测到更多的R循环,揭示了促进转录的集群R循环和导致DNA损伤的YMCAG相关R循环.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 生物化学 生物化学
背景情况:
- R-循环是核酸结构,生物学作用不明.
- 现有的R环检测方法缺乏精度和灵敏度.
研究的目的:
- 开发一种新的,高分辨率的方法来绘制R循环.
- 阐明R环在基因调节和基因组稳定中的功能.
主要方法:
- 开发了由核酶和测序 (RIAN-seq) 辅助的R循环识别,是一种无抗体的技术.
- 利用特定的核酶来消化非混合核酸,保持RNA:DNA杂交.
- 以基对分辨率映射了R循环,比以前的方法检测更多的数量级.
主要成果:
- RIAN-seq发现了大量的R循环,其中50%跨越60-130bp.
- 在招募转录增强因子的促进体上发现了以前无法检测到的R环集群.
- 确定了与R循环相关的Y(C/T) M(A/C) CAG动机,这些动机有助于跨物种的DNA损伤.
结论:
- R-循环有双重作用:在聚类时促进基因表达,当与YMCAG图案相关时危及基因组稳定性.
- RIAN-seq为R循环映射提供了前所未有的精度,进步了我们对它们的生物学意义的理解.
- 研究结果显示R循环是基因表达和基因组完整性的关键调节者.
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