人类RISC配对微RNA生物发生和转录后基因沉默
Richard I Gregory1, Thimmaiah P Chendrimada, Neil Cooch
1The Wistar Institute, Philadelphia, Pennsylvania 19104, USA.
Cell
|November 8, 2005
概括
RNA干扰利用了RNA诱导的沉默复合体 (RISC). 这项研究确定了RISC的组成,并表明它将microRNA处理与目标RNA分裂相结合,独立于ATP.
科学领域:
- 分子生物学分子生物学
- 在RNA生物学,RNA生物学.
- 基因规则 基因规则
背景情况:
- RNA干扰 (RNAi) 是一个关键的基因调节机制.
- 由RNA诱导的沉默复合体 (RISC) 中介于RNAi.
- 阿尔戈诺2被称为RISC的催化成分,但其完整的组成和组装仍然不清楚.
研究的目的:
- 为了阐明RISC复合物的多化合物组成和组装.
- 为了研究siRNA生成的机制,并通过RISC.目标RNA裂变.
- 为了确定ATP在RISC功能中的作用.
主要方法:
- 对RISC的生化复制.
- 使用前体微RNA (pre-miRNA) 和短干扰RNA (siRNA) 复合体进行准RNA裂变的测试.
- 导丝选择和ATP依赖性的分析.
主要成果:
- RISC是由Dicer,TRBP (双链RNA结合蛋白) 和Argonaute2.2组成的.
- RISC有效地使用前-miRNA作为siRNA源来分割目标RNA,显示出比siRNA复合体更高的活性.
- RISC选择性地结合了siRNA的导向链,并且在不需要ATP的情况下在多个分裂回合中运行.
结论:
- 该研究定义了RISC综合体的核心组件.
- 微RNA处理和准RNA裂变是由RISC介导的合过程.
- 对于RISC组装,miRNA处理或点RNA裂变来说,ATP不是必不可少的.
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