转录干扰在Drosophila melanogaster的Adh促进体开关中的作用
1Harvard University, Department of Biochemistry and Molecular Biology, Cambridge, Massachussetts 02138.
Nature
|January 19, 1989
概括
在Drosophila melanogaster中,酒精脱酶 (Adh) 基因的远端促销器的转录对于关闭近位促销器至关重要. 这确保了适当的发育基因表达时间.
科学领域:
- 分子生物学分子生物学
- 发展生物学 发展生物学
- 遗传学 遗传学 是一个
背景情况:
- 德洛索菲拉梅拉诺加斯特 (Drosophila melanogaster) 酒精脱酶 (Adh) 基因利用由增强剂调节的两个促进子 (近端和远端).
- 靠近的促销者是幼虫特异的,而远端的促销者在晚期幼虫和成年人中起作用.
- 促进剂和增强剂的空间布局表明潜在的监管相互作用.
研究的目的:
- 调查负责近端和远端Adh促进活性之间的发育转换的调节机制.
- 为了确定远端促进剂或成年增强剂是否在下调近端促进剂中发挥作用.
主要方法:
- 在不同发育阶段对Adh促进体活性进行遗传分析.
- 对促进体和增强体元素的操纵,以评估它们对基因表达的影响.
- 在野生类型和突变Drosophila melanogaster中观察Adh基因转录模式.
主要成果:
- 远端促进体的删除或缺失导致在幼虫发育期和成年期内持续的近端促进体活动.
- 在成年人中观察到异常的近位促进体活性,当其相对于远位促进体的位置发生变化时.
- 这些发现表明近位促销者抑制对远位促销者转录的依赖性.
结论:
- 从近端到远端的ADH促进体活动的发育过渡是由远端促进体的特定阶段激活控制的.
- 来自远端促进体的转录干扰积极抑制近端促进体,确保精确的发育基因调节.
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