cis作用序列负责Drosophila胚胎中双形mRNA的前部定位
1Howard Hughes Medical Institute, Columbia University College of Physicians and Surgeons, New York, N.Y. 10032.
Nature
|December 8, 1988
概括
双体 (bcd) mRNA的特定部分对于其在Drosophila胚胎中的前部定位至关重要. 这个序列也可以将其他转录指向同一个位置,揭示了形态原梯度形成的机制.
科学领域:
- 发展生物学 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:
- 在Drosophila melanogaster中,前体模式主要由双体 (bcd) 基因产物决定,这种基因产物是形成胚胎前极最高的梯度的形态原体.
- 这种双体梯度的形成依赖于双体信使RNA (mRNA) 在 oogenesis 过程中精确地定位到前极.
研究的目的:
- 为了确定对其前部定位负责的双状mRNA内部的特定序列.
- 为了确定这些序列是否足以赋予其他RNA分子的局部化.
主要方法:
- 对双形mRNA序列的分析,专注于3'未翻译区域.
- 涉及异质转录的实验,以测试已识别的序列是否足以进行本地化.
主要成果:
- 对于前部定位,需要在双mRNA的3'未翻译部分内设置约625个基对的离散区域.
- 这一识别的序列足以诱导前部局部化无关的转录.
- 负责序列具有特征,使其能够形成广泛的二次结构.
结论:
- 这些发现确切地指出了双形mRNA中一个特定的cis作用元素,这对其局部化至关重要.
- 这种元素可能与卵细胞细胞质中的序列特异性受体相互作用,用于转录定.
- 这项研究支持一种模型,其中双体转录在卵细胞的前极被选择性地捕获.
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