激活缺陷的TBP突变对酵母体转录启动的影响
T K Kim1, S Hashimoto, R J Kelleher
1Laboratory of Biochemistry and Molecular Biology, Rockefeller University, New York, New York 10021.
Nature
|May 19, 1994
概括
研究人员确定了酵母TATA结合多 (TBP) 突变,该突变阻止了依赖激活剂的转录,而不会影响基底活性. 这揭示了像GAL4-VP16这样的激活剂如何与TBP和TFIIB相互作用以调节转录启动.
科学领域:
- 分子生物学分子生物学
- 基因法规 基因法规
- 生物化学 生物化学
背景情况:
- 通过RNA聚合酶II的转录启动涉及一般因素和促进元素.
- 激活剂调节转录,通常针对一般转录因子,如TFIID和TFIIB.
- 了解激活器功能需要详细了解它们与转录机械的相互作用.
研究的目的:
- 研究转录启动中的激活器功能的分子机制.
- 为了确定激活剂,TBP和TFIIB之间的特定相互作用.
- 为了阐明如何选择性调节激活剂依赖转录.
主要方法:
- 酵母TBP的局部定向突变发生产生特定突变.
- 评估TBP突变对基底和激活剂依赖转录的影响.
- 调查TFIIB在活化剂和TBP突变物存在的情况下被招募到预启动复合体.
主要成果:
- 鉴定了酵母TBP突变,可以选择性地损害GAL4-VP16依赖转录,但不能损害基底转录.
- 证明GAL4-VP16影响TFIIB对早期预启动综合体的招聘.
- 表明影响与VP16或TFIIB相互作用的TBP突变破坏了这种招聘过程.
结论:
- GAL4-VP16的功能涉及与TBP的直接相互作用.
- 激活器功能导致特定的TBP-TFIIB-促进体复合物的诱导或稳定.
- 这些发现提供了关于激活剂介导的转录调节机制的见解.
相关概念视频
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