对于聚合组响应元素的核聚类,需要RNAi组件
Charlotte Grimaud1, Frédéric Bantignies, Manika Pal-Bhadra
1Institute of Human Genetics, CNRS, 141 rue de la Cardonille, 34396 Montpellier Cedex 5, France.
Cell
|March 15, 2006
概括
包括Dicer-2,PIWI和Argonaute1在内的RNA干扰 (RNAi) 机制对于Polycomb组 (PcG) 蛋白介导的基因沉默至关重要. RNAi组件维持PcG基因调节所必需的长距离DNA接触.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 染色体生物学 染色体生物学
背景情况:
- 聚合组 (PcG) 蛋白质是必不可少的表观遗传调节剂,通过聚合组响应元素 (PREs) 沉默家庭基因.
- 含有PRE的Fab-7调节元件可以诱导长距离的染色质相互作用,当存在多个副本时,可以增强PcG依赖基因沉默.
研究的目的:
- 为了研究RNA干扰 (RNAi) 机制在PcG介导的Fab-7元素中沉默的作用.
- 确定RNAi组件是否参与小RNAs的产生和在转基因Fab-7拷贝处保持长距离染色体接触.
主要方法:
- 使用了具有Fab-7元素多个副本的转基因Drosophila melanogaster模型.
- 评估了关键RNAi组件 (Dicer-2,PIWI,Argonaute1) 突变对PCG招募,小RNA产生和染色体关联的影响.
- 使用显微镜检查了RNAi因子与PcG体的局部化.
主要成果:
- RNAi组件中的突变通常不会影响PCG招募,但对于维持Fab-7副本之间的远程接触至关重要.
- RNAi机械组件参与了Fab-7的PCG介导沉默和转基因拷贝的小RNA生产.
- Dicer-2,PIWI和Argonaute1经常与PcG体同位,它们的突变减少了内源性同源基因的PcG依赖的染色体关联.
结论:
- RNAi机制在调节PCG染色体标的核组织方面发挥着新的作用.
- RNAi组件对于建立和维护强大的PCG介导基因沉默所需的更高阶染色体结构至关重要.
- 这项研究揭示了RNAi途径与通过染色体架构对发育基因的表观遗传调节之间的功能联系.
相关概念视频
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Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...


