Switching from Repression to Activation: MicroRNAs Can Up-Regulate Translation

@article{Vasudevan2007SwitchingFR,
  title={Switching from Repression to Activation: MicroRNAs Can Up-Regulate Translation},
  author={Shobha Vasudevan and Yingchun Tong and Joan A. Steitz},
  journal={Science},
  year={2007},
  volume={318},
  pages={1931 - 1934}
}
AU-rich elements (AREs) and microRNA target sites are conserved sequences in messenger RNA (mRNA) 3′ untranslated regions (3′UTRs) that control gene expression posttranscriptionally. Upon cell cycle arrest, the ARE in tumor necrosis factor–α (TNFα) mRNA is transformed into a translation activation signal, recruiting Argonaute (AGO) and fragile X mental retardation–related protein 1 (FXR1), factors associated with micro-ribonucleoproteins (microRNPs). We show that human microRNA miR369-3 directs… 
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It is shown that the relief of miRNA-mediated repression involving HuR can be recapitulated in different in vitro systems in the absence of stress, indicating that HuR alone is sufficient to relieve the miRNA repression upon binding to RNA ARE.
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