在体内,TAF含有和TAF独立的转录活性TBP的形式
1Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
概括
酵母基因转录涉及两种形式的TATA结合蛋白 (TBP):有或没有TBP相关因子 (TAF). 热冲击有利于含有TAF的TFIID复合体,解释了差异性基因激活.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 酵母遗传学 酵母遗传学
背景情况:
- 酵母中的转录活性与一般转录因子的促进物占用有关.
- 在酵母转录中,TATA结合蛋白 (TBP) 和相关因子 (TAF) 的作用需要进一步阐明.
研究的目的:
- 研究参与酵母转录活动的TBP的不同形式.
- 确定热冲击如何影响使用含有TBP的复合物.
- 探索特定酵母基因中TFIID依赖转录的基础.
主要方法:
- 在酵母中分析TBP,TFIIA,TFIIB和TAF的促进体占用率.
- 在正常和热冲击条件下的TBP形式利用率的比较.
主要成果:
- 酵母转录活性与TBP,TFIIA和TFIIB占用率相关,但与TAFs无关.
- TBP存在至少两种活性形式:TFIID (含TAF) 和单独的TBP或其他复合物 (不含TAF).
- 热冲击治疗增加了TFIID复合物的相对利用率.
结论:
- 不同形式的TBP,包括TFIID和没有TAF的TBP,在酵母中具有转录活性.
- 这些TBP形式的差异性促销器特异性关联影响了基因转录.
- 热冲击改变了TBP形式之间的平衡,有利于TFIID,并可能解释这种复杂的基因特异性要求.
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