保持let-7异常调节RNA的序列和时间表达
A E Pasquinelli1, B J Reinhart, F Slack
1Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
Nature
|November 18, 2000
概括
Let-7小RNA调节了许多动物物种的发育时间. 这种微RNA保留在脊椎动物和无脊椎动物中,控制晚期发育过渡.
科学领域:
- 发育生物学 发展生物学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- *C. elegans*的发育时间由小RNAs调节,包括lin-4和let-7.
- lin-4和let-7RNAs针对蛋白质编码基因,对它们的表达进行负调节.
- 这些RNAs不是同类的,但具有共同的调节机制.
研究的目的:
- 为了研究let-7RNA的进化保存.
- 为了确定let-7RNA是否在各种动物物种的发育时间中起作用.
- 为了比较不同种群中let-7和lin-4RNA的存在.
主要方法:
- 从广泛的动物物种中提取RNA.
- 使用分子技术检测小RNA.
- 对let-7RNA表达时间进行比较分析.
主要成果:
- 让-7RNAs (大约) 在 21个核酸) 在脊椎动物,类动物,半弦动物,软体动物,类动物和节肢动物中检测到.
- 在任何测试物种中都没有检测到lin-4RNA.
- let-7RNA的表达时间保持不变,在*C. elegans*和*Drosophila*的晚期幼虫阶段和类动物和软体动物的成年阶段出现.
结论:
- Let-7调节RNA在广泛的动物类中是进化保守的.
- let-7RNA很可能控制了整个动物类遗传的晚期发育过渡.
- 其他物种中没有lin-4RNA,这表明线虫在线虫中发挥了更具体的作用.
关键词:
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