耐受性值是胚胎发育过程中对DNA损伤的反应的基础
Gloria Jansen1,2, Daniel Gebert1,2, Tharini Ravindra Kumar1
1Department of Genetics, University of Cambridge, Cambridge CB2 3EH, United Kingdom.
Genes & development
|July 25, 2024
概括
胚胎细胞通过发展抗性值,意外地耐受了可转移元素 (TE) 造成的DNA损伤. 这保护了在生殖线发育期间的基因组完整性,即使有显著的DNA双链断裂 (DSBs).
科学领域:
- 发展生物学 发展生物学
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 可移植元素 (TE) 在生殖系中活跃,可能会破坏基因并损害生殖细胞的活力.
- 由于P元素转位子引起的Drosophila中的P-M杂交失调导致不育,但尽管DNA受损,但在生殖细胞中很少出现新的TE插入.
研究的目的:
- 为了研究为什么在P-M杂交失调过程中,胚胎细胞在没有新的可转移元素 (TE) 插入的情况下积累DNA双链断裂 (DSB).
- 确定DSB对生殖细胞活力的影响以及DNA损伤耐受性值在生殖细胞发育中的作用.
主要方法:
- 利用工程CRISPR-Cas9系统诱导DNA双链断裂 (DSB) 在沉默的P元素和Drosophila的非编码序列.
- 评估不同发育阶段诱导的DSBs的生殖细胞损失和活力 (线粒细胞与介质细胞过渡).
主要成果:
- 在沉默的P元素或非编码DNA中产生DSB诱导了生殖细胞损失,独立于基因破坏.
- 线性生殖细胞对DSBs表现出剂量依赖的敏感性,导致细胞循环停止和损失.
- 胚胎细胞在线粒细胞转变后对DSBs变得更耐受,允许 oogenesis 尽管累积的基因组损伤继续进行.
结论:
- 在胚胎发育过程中,DNA损伤耐受性值对于保护基因组完整性至关重要.
- 胚胎细胞对DSBs的敏感性随着发育阶段而变化,转移后的细胞表现出更高的耐受性.
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