从抑制转向激活:microRNAs可以对翻译进行上调
Shobha Vasudevan1, Yingchun Tong, Joan A Steitz
1Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, Boyer Center for Molecular Medicine, 295 Congress Avenue, New Haven, CT 06536, USA.
概括
微RNAs (miRNAs) 可以通过与信使RNA (mRNA) 中的AU丰富元素 (AREs) 结合来激活细胞周期停止期间的基因翻译. 微核核蛋白 (miRNP) 的这种激活功能似乎随着细胞增殖而波动.
科学领域:
- 分子生物学分子生物学
- 基因规则 基因规则
- 转录后控制 转录后控制
背景情况:
- 在mRNA 3'UTR中,富含AU元素 (AREs) 和microRNA目标位调节基因表达后转录.
- 在细胞循环停止期间,瘤亡因子-α (TNFalpha) mRNA中的AREs招募阿尔戈诺特 (AGO) 和脆弱的X精神衰退相关蛋白1 (FXR1),形成微核核蛋白 (miRNP).
研究的目的:
- 调查微RNAmiR369-3在指导蛋白质与ARE结合以实现翻译激活中的作用.
- 为了确定其他microRNA在细胞周期停止和增殖期间是否表现出类似的翻译调节模式.
主要方法:
- 研究了miR369-3与ARE和相关蛋白质 (AGO,FXR1) 的相互作用.
- 分析了细胞周期停止和增殖期间Let-7和miRcxcr4对目标mRNA的翻译调节.
主要成果:
- 人类微RNA miR369-3 将AGO和FXR1的招募指导到AREs,激活mRNA翻译.
- 在细胞周期停止时,Let-7和miRcxcr4上调目标mRNA转化,但在增殖细胞中抑制它.
- 通过miRNPs进行翻译激活是细胞循环停止期间观察到的常见功能.
结论:
- 微RNA介导的翻译激活是细胞循环停止过程中的重要机制.
- 微RNA-核糖核蛋白 (miRNP) 介导的翻译调节在整个细胞周期中表现出抑制和激活之间的振荡模式.
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