酵母和人类TFIID之间的功能差异局限于高度保护的区域
B P Cormack1, M Strubin, A S Ponticelli
1Department of Biological Chemistry, Harvard Medical School, Boston, Massachusetts 02115.
Cell
|April 19, 1991
概括
尽管保留了核心域,但人类的TFIID (转录因子II D) 支持酵母菌的生长很差. 核心域内的特定物种差异,而不是N终端区域,导致转录因子活性的功能区别.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 转录因子II D (TFIID) 是一种高度保守的通用转录因子,对真核生物基因表达至关重要.
- 在真核生物中,TFIID的核心域具有高序列相同性 (>80%) 和类似的生化特性.
研究的目的:
- 为了研究酵母和人类TFIID之间的功能差异,尽管它们的核心域被保留了.
- 在TFIID中确定负责酵母菌中特定物种功能不相容性的特定区域.
主要方法:
- 对表达人类TFIID和酵母-人类杂交TFIID结构的酵母细胞的功能分析.
- 评估细胞生长作为测量TFIID功能 in vivo.
- 对核心领域区域进行比较分析,以精确确定功能决定因素.
主要成果:
- 与具有内源性酵母TFIID的酵母细胞相比,表达人类TFIID的酵母细胞的生长严重受损.
- TFIID的N终端区域对于酵母细胞活力并不重要,因为只有核心域支持生长.
- 在TFIID的核心保护区域内,特定的区域负责观察到的特定物种的功能差异.
结论:
- 酵母和人类TFIID之间的功能不兼容是由于它们保存的核心领域内的变异引起的.
- 这些TFIID的特定物种差异可能来自改变的DNA结合亲缘关系或与转录机械组件的明显相互作用.
- 了解这些变异可以了解基本转录过程的演变和调节.
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