反对的microRNA家族调节小鼠胚胎干细胞的自我更新
Collin Melton1, Robert L Judson, Robert Blelloch
1The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, Center for Reproductive Sciences, Program in Biomedical Sciences, University of California San Francisco, San Francisco, California 94143, USA.
Nature
|January 8, 2010
概括
微RNAs调节细胞的命运. 在缺乏DGCR8的胚胎干细胞中,Let-7miRNA抑制了自我更新,而ESC特定的miRNA则促进了自我更新,揭示了细胞分化中的关键机制.
科学领域:
- 发育生物学 发展生物学
- 分子生物学分子生物学
- 干细胞生物学 干细胞生物学
背景情况:
- 胚胎干细胞 (ESC) 必须在分化过程中使自我更新停止,并激活组织特定的程序.
- DGCR8对于微RNA (miRNA) 生物发生是必不可少的;它的缺失阻止了ESC沉默自我更新.
研究的目的:
- 研究let-7miRNAs和ESC细胞周期调节 (ESCC) miRNAs在调节ESC自我更新和分化中的作用.
- 阐明这些miRNA家族控制细胞命运的分子途径.
主要方法:
- 在小鼠ESC中对DGCR8进行基因操纵.
- 引入特定的miRNA家族 (let-7和ESCCmiRNAs).
- 细胞测试以评估自我更新和分化.
- 基因表达概况和生物信息学分析.
主要成果:
- let-7 miRNAs抑制了Dgcr8的自我更新,但不是野生类型的ESC.
- 在Dgcr8中,ESCC的miRNAs抵消了let-7对Dgcr8的自我更新的抑制作用.
- let-7抑制,而ESCC小RNA间接激活,许多自我更新基因.
- 抑制let-7促进体细胞去分化成为诱导的多能干细胞.
结论:
- let-7和ESCCmiRNAs利用共同的途径来稳定自我更新或分化细胞命运.
- 这些发现提供了关于干细胞多能性和分化的复杂miRNA介导调节的见解.
- 莱特-7家族在促进体细胞重编程方面发挥着至关重要的作用.
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