在人类c-myc基因中过早终止转录的序列要求
1Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98104.
Cell
|April 22, 1988
概括
研究人员在人类c-myc基因中确定了导致过早转录终止的特定DNA序列. 这些序列位于外子1/内子1边界的上游,调节较短的RNA分子的产生.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 转录控制 转录控制
背景情况:
- 人类c-myc基因对细胞生长至关重要,在癌症中经常出现失调.
- 转录的过早终止是已知的基因表达的调节机制.
- 了解终结的序列要求是破译基因调节的关键.
研究的目的:
- 研究人类c-myc基因中导致过早转录终止的序列元素.
- 为了确定这些终结信号的确切位置和特征.
- 为了区分转录终结和RNA处理作为截断RNAs的原因.
主要方法:
- 用于研究转录的Xenopus卵细胞注射系统.
- 对RNA聚合酶II活性和转录3'末端形成的分析.
- 在c-myc基因内对特定DNA序列的删除分析.
- 在人体细胞和切割的卵细胞核中进行核流量测试.
主要成果:
- 截断的RNA在卵细胞中产生,其5'端位于P1/P2促进体和3'端位于外子1/内子1结点附近.
- 终止是通过转录终止发生的,而不是通过RNA处理.
- 一个95个基的区域 (-130到-35相对于外子1/intron 1) 包含了终结信号.
- 终结是取决于导向的,并且在异质促进者的下游运行.
结论:
- 特定的上游序列,而不是聚-T延伸,决定了c-myc转录终结的3'末端形成位置.
- 这些序列作为控制过早转录终止的cis作用元素起作用.
- 这些发现为人类c-myc基因的调节机制提供了洞察力.
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