皮维相互作用RNAs保护DNA免受损失在Oxytricha基因组重组过程中
Wenwen Fang1, Xing Wang, John R Bracht
1Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Cell
|December 11, 2012
概括
来自母核指导基因组编程的Piwi相互作用RNAs (piRNAs) 在Oxytricha. 这些小RNA确保保留基本的DNA,作为跨代表观遗传载体.
科学领域:
- 表观遗传学和分子生物学
- 基因组学和遗传学研究研究.
- 状原生动物研究研究
背景情况:
- 像Oxytricha这样的状原生动物表现出基因组双重性,具有不同的体质和生殖系基因组.
- 实体基因组的开发涉及到~95%的生殖基因组DNA的编程消除,包括转子.
- 了解这种选择性DNA消除的机制对于理解遗传和基因组调节至关重要.
研究的目的:
- 为了研究小RNAs在指定基因组区域的作用,在体质基因组发育过程中保留在Oxytricha.
- 确定母体的Piwi相互作用RNA (piRNA) 是否可以指导下一代基因组的表观遗传编程.
- 探索小RNA作为表观遗传信息的跨代载体的潜力.
主要方法:
- 对Oxytricha piRNA种群的分析及其对生殖系和体内基因组的映射.
- 在发育中的核中注入与正常删除的基因组区域相对应的合成piRNA.
- 在后代中注射基因组区域的保留的评估.
主要成果:
- 氧特里卡piRNAs主要映射到构成体质基因组的胚胎DNA中保留的5%左右.
- 母亲的piRNAs指定基因组区域在DNA消除过程中保留.
- 针对通常被删除区域的合成piRNAs成功诱导了它们在后代的保留.
结论:
- 皮维相互作用RNAs (piRNAs) 是Oxytricha中代际表观遗传信息传递的关键媒介.
- 小RNA作为基因组编程的关键决定因素,指导DNA的选择性保留.
- 这项研究揭示了由小RNA介导的跨代表观遗传的新奇机制.
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