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.
bioRxiv : the preprint server for biology
|April 1, 2024
概括
在线虫中,编程DNA消除 (PDE) 涉及DNA双链断裂 (DSBs),这些断裂通过独特的切除配置文件进行处理. 端粒愈合优先发生在保留的DNA末端,而不是被消除的末端,确保染色体碎片化.
科学领域:
- 遗传学 遗传学 是一个
- 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) 对基因组完整性至关重要,但对于特定的生物过程也至关重要,如V(D) J重组和编程DNA消除 (PDE).
- 在线虫中,DSBs参与PDE,通常通过端粒添加来治愈,尽管染色体碎片化期间DSB形成和处理的机制尚不清楚.
- 虽然已知端粒添加部位,但导致线虫染色体分裂的特定DSBs,特别是在PDE的背景下,尚不清楚.
研究的目的:
- 研究在线虫Ascaris中编程DNA消除过程中DSB的时间和处理.
- 在染色体分裂的背景下,描述DSB末端的性质及其修复机制.
主要方法:
- 利用END-seq技术分析阿斯卡里斯胚胎中的DNA断裂末端.
- 检查了相对于线粒分裂的DSB引入的时间,并描述了DNA末端切除配置文件.
主要成果:
- DSBs是在线索分裂之前引入的,并经历了广泛的,特定于位点的末端切除,产生3'突起.
- 与消除的末端相比,与保留的DNA末端相比,端粒愈合发生的频率要高得多.
- 消除的DNA片段被隔离到微核中,可能会阻碍端粒的愈合.
结论:
- DSB的偏向修复以Ascaris结束,可能是由于消除的DNA被封存到微核中,阻碍了端粒愈合.
- 在阿斯卡里斯和帕斯卡里斯的消除DNA中的额外的DSB作为一个安全机制,以确保在PDE期间完全染色体破裂.
- 了解PDE中的DSB处理为线虫中基因组碎片化和维护提供了见解.
关键词:
阿斯卡里斯是一种.在DNA双链断裂过程中,最后一个-seqqq.帕拉斯卡里斯 (Parascaris) 是一种虫.切除结束切除结束微核是微核中的一个.形线虫形线虫是什么意思编程的 DNA 消除.端粒的添加 端粒的添加更多相关视频
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