Spo11通过在拓应力位点的协调切割产生空隙
Silvia Prieler1, Doris Chen1, Lingzhi Huang1
1Max Perutz Labs Vienna, University of Vienna, Department of Chromosome Biology, Vienna, Austria.
Nature
|June 10, 2021
概括
在半转化过程中,Spo11会造成DNA缺口,而不仅仅是断裂. 这些双双链断裂 (DSB) 影响基因转换,并可以驱动进化多样性或引起生殖系异常.
科学领域:
- 遗传学
- 分子生物学
- 细胞生物学
背景情况:
- 微生物重组对于染色体分离和生育至关重要.
- 它是由Spo11生成的编程DNA双链断裂 (DSB) 启动的.
研究的目的:
- 描述Spo11诱导的新型DNA损伤.
- 阐明这些病变的机制和基因组分布.
- 了解它们在介质重组和基因组进化中的作用.
主要方法:
- 用单个基因对精度对Spo11诱导的片段进行全基因组映射.
- 对DNA序列模式和片段长度周期性的分析.
- 与拓酶II结合部位的相关性
主要成果:
- 发现由双DSBs形成的Spo11诱导的DNA缺口 (3400个基对).
- 这些差距在DSB热点上增加了,但也普遍存在.
- Spo11裂变受到DNA曲性和拓应力的影响,有利于特定的DNA面.
- 双DSB占启动事件的20%左右,可以导致基因转换,删除或插入.
结论:
- Spo11同时产生DSB和双DSB,从而产生空隙.
- 在Spo11裂变点选择中,DNA曲性和拓应力是关键因素.
- 双DSB有助于遗传多样性,并可能导致病原性生殖系异常.
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