调控核糖体RNA的物种特异转录的分子机制
S P Bell1, C S Pikaard, R H Reeder
1Howard Hughes Medical Institute, Department of Biochemistry, University of California, Berkeley 94720.
Cell
|November 3, 1989
概括
特定物种的转录因子hUBF和xUBF结合相似的DNA,但不会互相替代. 与SL1的明显的蛋白质-蛋白质相互作用决定了特定物种的促进剂激活.
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:
- 核糖体RNA (rRNA) 转录对于细胞生长至关重要,并由RNA聚合酶I (Pol I) 调节.
- 在rRNA基因转录中的促进者识别表现出物种特异性,这是一个鲜为人知的现象.
- 像人类UBF (hUBF) 和Xenopus UBF (xUBF) 这样的转录因子是Pol I转录的关键调节者.
研究的目的:
- 在rRNA转录中研究物种特异性促进体识别的分子基础.
- 为了确定物种特异性是否由DNA结合或蛋白质与蛋白质相互作用介导.
主要方法:
- 人类UBF (hUBF) 和Xenopus UBF (xUBF) 的分离和表征.
- 使用纯化因子和促进体DNA进行重建的转录试验.
- 使用生物化学方法分析UBF因子和SL1 (一种特定物种的Pol I激活剂) 之间的复合形成.
主要成果:
- 无论是hUBF还是xUBF,都与rRNA基因促进体内的相同DNA序列元素结合.
- 在复合的转录系统中,hUBF和xUBF在功能上是不可互换的.
- hUBF和xUBF与人类SL1形成了独特的复合体,不论促进者的起源物种如何.
结论:
- 在rRNA基因转录中的物种特异性不仅仅是由UBF因子的DNA序列识别决定的.
- UBF和SL1之间的特定蛋白质-蛋白质相互作用是特定物种促进体选择性的关键决定因素.
- 这凸显了转录因子复合体形成在调节特定物种基因表达中的重要性.
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