由Ultrabithorax蛋白在培养的Drosophila细胞中的转录激活和抑制
M A Krasnow1, E E Saffman, K Kornfeld
1Department of Biochemistry, Stanford University, CA 94305.
Cell
|June 16, 1989
概括
在Drosophila melanogaster中,同源基因Ultrabithorax (Ubx) 和Antennapedia (Antp) 控制基因表达. Ubx蛋白质通过结合促进体中的特定DNA序列,起到转录激活剂和抑制剂的作用.
科学领域:
- 发育生物学是发展生物学.
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
背景情况:
- 像Ultrabithorax (Ubx) 和Antennapedia (Antp) 这样的同源基因对于在Drosophila发育过程中建立metameric身份至关重要.
- 这些基因被认为通过调节下游目标基因的表达来发挥其功能.
研究的目的:
- 研究Ubx蛋白对基因促进体的直接调节活动.
- 确认Ubx蛋白作为转录激活剂和抑制剂在细胞测定中的预测作用.
主要方法:
- 在培养的Drosophila melanogaster细胞中使用了共传染试验.
- 结合了Ubx和Antp基因的促进子区域,以报告构造来评估监管活动.
- 分析了Ubx蛋白对转录水平的影响,并确定了特定的结合部位.
主要成果:
- 证明Ubx蛋白可以抑制Antennapedia (Antp) 促销器融合并激活Ubx促销器融合.
- 证实Ubx蛋白调节精确启动的Antp P1和Ubx转录的水平.
- 确定了Ubx促进体激活必需的Ubx结合位点的下游集群,并表明这些序列对异质促进体进行调节.
结论:
- Ubx蛋白质既可以作为转录抑制剂,也可以作为激活剂.
- Ubx蛋白的调节功能通过直接结合促进子区域内的序列来调节.
- Ubx蛋白家族表现出类似的调节能力,在突变形式中具有潜在的模块化设计.
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