人类TAFII250的克隆和表达:与TBP相关的因子,涉及细胞循环调节
1Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley 94720.
Nature
|March 11, 1993
概括
研究人员确定了hTAFII250,这是对基因转录调节至关重要的关键协作激活蛋白. 这种TBP相关因子 (TAF) 将转录控制与细胞周期进展联系起来.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 细胞生物学 细胞生物学
背景情况:
- 由RNA聚合酶II进行的基底转录需要辅助因子 (TFIIA-J).
- 共激活剂对于转录激活剂调节至关重要,但不是基底转录.
- 一些联合激活剂与TATA结合蛋白 (TBP) 结合,形成TFIID复合体.
研究的目的:
- 定义TBP和TBP相关因子 (TAF) 之间的关系.
- 为了克隆,表达和描述第一个人类TAF,hTAFII250.0.
主要方法:
- 克隆和表达复合的hTAFII250.0.
- 在体外和基于酵母的结合测试以评估TBP相互作用.
- 对TFIID复杂形成的分析.
主要成果:
- 对于hTAFII250的基因与CCG1相同,CCG1是一种参与细胞循环进展的基因.
- 再组合的hTAFII250直接与TBP结合.
- hTAFII250参与TFIID复合体的形成.
结论:
- hTAFII250是第一个被发现的人类TAF.
- 这个TAF可以通过与TBP和其他TAF互动,在TFIID组装中发挥核心作用.
- hTAFII250将转录控制与细胞周期联系起来.
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