在线虫编程DNA消除过程中DNA双链断裂的末端切除和端粒愈合
Brandon Estrem1, Richard E Davis2, Jianbin Wang1,3
1Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN 37996, USA.
Nucleic acids research
|July 2, 2024
概括
在线虫中的编程DNA消除 (PDE) 依赖于DNA双链断裂 (DSB). 端粒愈合是特定于保留的DSB末端,防止消除并确保在发育过程中确保基因组完整性.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- DNA双链断裂 (DSB) 对于生物过程至关重要,如重组和编程DNA消除 (PDE).
- 虽然在线虫中已知多元体添加到DSB中,但在PDE期间DSB分裂染色体的理解仍然很差.
- 阿斯卡里斯线虫在PDE期间利用DSB进行染色体碎片化.
研究的目的:
- 描述参与阿斯卡里斯线虫编程DNA消除 (PDE) 的DNA双链断裂 (DSB).
- 阐明线虫染色体碎片化过程中DSB形成,切除和端粒愈合的机制.
主要方法:
- 分析了来自Ascaris线虫的胚胎.
- 使用END-seq技术识别和描述DSB站点.
- 研究了DNA切除模式和端粒添加.
主要成果:
- DSBs是在线索分裂之前引入的,并经历了广泛的末端切除,产生独特的配置文件和3'-overhangs.
- 端粒愈合最好发生在保留的DSB端,而不是消除的,可能是由于微核封存.
- 消除的DNA中的额外DNA断裂作为阿斯卡里斯和帕拉斯卡里斯的PDE的防故障机制.
结论:
- 在线虫PDE期间的端粒愈合是特定于该位点的,有利于保留的染色体末端.
- DSBs的偏向修复与被消除的DNA被封存到微核中有关.
- DSBs和随后的端粒添加是精细调节的过程,对于线虫编程的DNA消除至关重要.
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