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Chromatin Immunoprecipitation (ChIP) using Drosophila tissue
Published on: March 23, 2012
染色素相关的RNA干扰成分有助于Drosophila的转录调节
Filippo M Cernilogar1, Maria Cristina Onorati, Greg O Kothe
1Dulbecco Telethon Institute, Epigenetics and Genome Reprogramming, IRCCS Fondazione Santa Lucia, Via del Fosso di Fiorano 64, 00143 Rome, Italy.
Nature
|November 8, 2011
概括
关键的RNA干扰 (RNAi) 蛋白Dicer 2 (DCR2) 和Argonaute 2 (AGO2) 与活性基因相关并影响RNA聚合酶II动态,揭示了它们在动物的转录调节中的作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- RNA干扰 (RNAi) 途径主要在细胞质中通过转录后调节基因表达.
- 已知RNAi组件在表观遗传调节和异染色素形成中的核作用.
- 动物中RNAi介导的转录基因沉默和染色质动态的机制在很大程度上仍然不清楚.
研究的目的:
- 研究关键RNAi组件Dicer 2 (DCR2) 和Argonaute 2 (AGO2) 在多细胞动物的染色质动力学和转录调节中的核功能.
- 阐明DCR2和AGO2在控制RNA聚合酶II活性和定位方面的作用.
主要方法:
- 对 DCR2 和 AGO2.2 的染色体关联研究.
- 对DCR2和AGO2功能丧失突变体的转录缺陷的分析.
- 在DCR2和AGO2突变基因背景下,对热冲击后的RNA聚合酶II动态的评估.
- 与AGO2相关的小RNA深度测序 (AGO2 RIP-seq).
主要成果:
- DCR2和AGO2与染色质相关,特别是转录活跃的 euchromatic loci.
- DCR2或AGO2功能的丧失会扰乱RNA聚合酶II在促进体上的定位.
- 在DCR2和AGO2的突变损害全球RNA聚合酶II的动态,特别是在热冲击后.
- 在热冲击后,AGO2富含小RNA映射到促销器和遗传位点,对热冲击后的反意义链有偏见.
结论:
- DCR2和AGO2在全球范围内与动物细胞中的转录活性位点有关.
- 这些RNAi成分在转录基因沉默和染色质动态中发挥着重要作用.
- DCR2和AGO2可能控制RNA聚合酶II的过程性,从而塑造转录组.
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