改变U snRNA基因促进者的RNA聚合酶特异性
I W Mattaj1, N A Dathan, H D Parry
1European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Cell
|November 4, 1988
概括
研究人员发现,RNA聚合酶III可以直接识别转录启动部位. 这一发现使得Xenopus中RNA聚合酶II和III的特定U6和U2基因促进物的产生成为可能.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 生物化学 生物化学
背景情况:
- 已知Xenopus tropicalis U6基因促进体被RNA聚合酶II和III转录.
- 了解控制聚合酶特异性的不同调节元素对于基因表达研究至关重要.
研究的目的:
- 阐明特定的DNA元素决定RNA聚合酶II与RNA聚合酶III转录的U6促进体.
- 研究RNA聚合酶III在识别转录启动位点方面的潜在直接作用.
- 设计具有改变聚合酶特异性的新型促进剂.
主要方法:
- 使用位点定向突变发生的U6促进体结构和功能的分析.
- 用RNA聚合酶II和III进行比较的转录试验.
- 改造U6和U2基因促进体的工程.
主要成果:
- 该U6促进体含有RNA聚合酶III (TATA样序列,启动区域) 的不同元素和两种聚合酶的共同元素.
- 在转录开始部位的严格纯素要求表明RNA聚合酶III的直接识别.
- 突变分析支持RNA聚合酶III参与促体选择的假设.
- 成功创建了一个RNA聚合酶II特异性的U6促销器,并将U2促销器转换为RNA聚合酶III特异性.
结论:
- RNA聚合酶III可能直接识别转录启动部位,在促进体选择中发挥关键作用.
- 该研究提供了对差异性聚合酶招募机制的见解.
- 工程发起者为Xenopus中的特定基因表达研究提供了有价值的工具.
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