在D. melanogaster中调节性分化基因的替代拼接的控制
R N Nagoshi1, M McKeown, K C Burtis
1Department of Biological Sciences, Stanford University, California 94305.
Cell
|April 22, 1988
概括
这项研究揭示了性别决定中的关键基因,如变压器 (tra) 和双性 (dsx),由RNA处理水平上的上游基因调节. 这种RNA拼接机制解释了控制性差异化的等级相互作用.
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:
- 许多生物体的性别决定涉及复杂的调节基因层次结构.
- 不同RNA处理,特别是替代拼接,在生成性别特异性转录中起着至关重要的作用.
- 变压器 (tra) 和双性 (dsx) 基因是性别差异化的核心,产生不同的RNA异型.
研究的目的:
- 研究上游调节基因的突变如何影响tra和dsx转录的RNA处理.
- 阐明RNA处理在性别确定层次结构中的作用.
- 为了确定性差异化中的基因相互作用的顺序.
主要方法:
- 对关键性别决定调节基因突变体中的RNA处理模式的分析.
- 在不同的遗传条件下检查tra和dsxRNA转录处理.
- 基因研究以推断调节性基因相互作用的等级顺序.
主要成果:
- 上游调节基因的突变直接影响tra和dsx的RNA处理.
- 调节tra和dsx发生在RNA剪接的水平上.
- 提出了基因相互作用的等级顺序:X:A > Sxl > tra > tra-2 > dsx >= ix >终端分化.
结论:
- RNA拼接是性别确定途径中的关键调节机制.
- 观察到的RNA处理事件足以解释性别确定层次结构中的功能相互作用.
- 这项研究为性别决定调节的遗传模型提供了分子证据.
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