AU结合蛋白招募外体来降解含有ARE的mRNAs
1Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, University of California, San Diego, La Jolla, CA 92093, USA.
Cell
|November 24, 2001
概括
富含AU的元素 (AREs) 在哺乳动物中引发了快速的mRNA衰变. 人类外体,在ARE结合蛋白的帮助下,降解这些不稳定的RNA,澄清了基因调节的关键机制.
科学领域:
- 分子生物学分子生物学
- 基因表达规范 基因表达规范
- 在RNA代谢过程中.
背景情况:
- 在3'非翻译区域的富含AU元素 (ARE) 控制哺乳动物mRNA的稳定性.
- 由于AREs诱导快速mRNA衰变的确切机制在很大程度上是未知的.
- 外体复合体介导酵母中的3'-to-5'mRNA降解.
研究的目的:
- 描述人体外基因组,阐明它在ARE介导的mRNA衰变中的作用.
- 研究人类外体和含有ARE的RNA之间的相互作用.
- 为了确定参与外体对不稳定的mRNA的招募的因素.
主要方法:
- 净化和质谱分析人类外体组合的复杂性.
- 开发一个无细胞系统来研究RNA衰变动力学.
- 测试用于评估ARE结合蛋白,外体和点RNA之间的相互作用.
主要成果:
- 人类外体组合类似于它的酵母对应物.
- 哺乳动物外体对含有ARE的RNAs的快速降解至关重要.
- ARE-mRNAs的外体介导降解需要ARE结合蛋白来进行招募.
结论:
- 人类外体在本质上不稳定的ARE含有mRNAs的衰变中发挥着关键作用.
- ARE结合蛋白作为适配剂,将ARE与外体连接起来,以促进mRNA降解.
- 这项研究阐明了哺乳动物转录后基因调节的基本机制.
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