转录复制冲突驱动R循环依赖的核细胞驱逐,并要求DOT1L活动用于转录恢复
Marcel Werner1, Manuel Trauner1, Tamas Schauer1
1Chromosome Dynamics and Genome Stability, Institute of Epigenetics and Stem Cells, Helmholtz Munich, Feodor-Lynen-Strasse 21, 81377 München, Germany.
Nucleic acids research
|February 23, 2025
概括
转录复制冲突 (TRCs) 改变染色质结构,并引发基因组的不稳定性. 在TRC部位的H3K79甲基化有助于转录恢复和分辨率,突出了关键的表观遗传机制.
科学领域:
- 分子生物学分子生物学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
- 基因组学就是基因组学.
背景情况:
- 转录和复制是基本的细胞过程,可以相互干扰,导致转录复制冲突 (TRCs).
- 通过改变染色质结构和表观基因组景观,TRCs可以破坏基因组的稳定.
- 了解TRC地点的动态分子事件对于理解基因组不稳定性及其在疾病中的作用至关重要.
研究的目的:
- 为研究转录复制冲突 (TRCs) 设计一种新的可诱导记者系统.
- 描述TRC地点的局部染色质结构和表观基因组的动态变化.
- 调查H3K79甲基化在TRC分辨率和转录恢复中的作用.
主要方法:
- 开发一种可诱导的记者系统,使用基因组集成的R循环易发生序列.
- 动态染色体结构变化的特征,包括核细胞占用和复制分叉进展.
- 分析全球复制应激反应和特定的表观遗传修饰,如H3K79甲基化.
- 抑制H3K79甲基转移酶DOT1L以评估其对转录和DNA损伤的影响.
主要成果:
- 诱导性TRC导致核细胞占用率降低,并导致冲突地点的复制分叉阻塞.
- 少数诱导的TRCs会触发可测量的全球复制应激反应.
- TRC形成与R环形成地点的H3K79甲基化特异性增加有关.
- DOT1L抑制会加剧DNA损伤并降低转录输出,这表明H3K79甲基化在TRC分辨率中的作用.
结论:
- TRCs在局部染色质结构和表观基因组中诱导了显著的动态变化.
- H3K79甲基化是一种TRC依赖的表观遗传标记,可促进转录恢复和分辨率.
- 这种TRC站点上的表观遗传书签机制与癌症等疾病有关.
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