拉斯是由let-7微RNA家族调节的
Steven M Johnson1, Helge Grosshans, Jaclyn Shingara
1Department of Molecular, Cellular and Developmental Biology, Yale University, P.O. Box 208103, New Haven, CT 06520, USA.
Cell
|March 16, 2005
概括
Let-7微RNA家族在虫和人类中调节RAS基因表达. 人类肺瘤中较低的Let-7水平与较高的RAS蛋白相关,这表明它在癌症中起作用.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 发展生物学 发展生物学
背景情况:
- 微RNAs (miRNAs) 是真核生物中基因表达的关键调节者.
- Let-7 miRNA家族在发育过程中起着至关重要的作用,包括细胞分化.
- 人类癌症中RAS基因经常发生突变,并参与细胞生长和增殖.
研究的目的:
- 研究let-7 miRNA家族与RAS通路之间的调控关系.
- 确定let-7是否直接针对模型生物和人类的RAS基因.
- 探索let-7和RAS在肺癌背景下的潜在作用.
主要方法:
- 报告者基因测试评估了let-7介导的let-60/RAS.调节.
- 在C. elegans发育过程中对let-7家族成员表达的分析.
- 在人类肺瘤组织中检查let-7和RAS表达水平.
主要成果:
- 已经证明,let-7家族在C. elegans中负面调节了let-60/RAS.
- 在let-60/RAS的3'UTR中确定了多个let-7互补位点 (LCS),它们介于let-7依赖抑制.
- 人类RAS基因3'UTR也含有LCS,这表明let-7调节得到保护.
- 在人类肺部瘤中观察到减少let-7表达和提高RAS蛋白水平.
结论:
- 在let-7miRNA家族直接通过保守的机制抑制RAS基因表达.
- 莱特-7-RAS轴的失调,降低了莱特-7和增加了RAS,与人类肺部瘤发生有关.
- 这项研究提供了let-7功能与癌症发展之间的分子联系.
相关概念视频
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