Inhibition of translation in living eukaryotic cells by an RNA G-quadruplex motif
Inhibition of translation in living eukaryotic cells by an RNA G-quadruplex motif
复制标题
DOI：
10.1261/rna.1001708
复制
发表时间：
2008-07-01
期刊：
影响因子：
4.5
通讯作者：
Kurreck, Jens
中科院分区：
文献类型：
--
作者：
Arora, Amit;Dutkiewicz, Mariola;Kurreck, Jens
富含鸟嘌呤的序列可以采用分子内四链结构，称为G-四链体。这些基序已经在DNA水平上进行了深入的研究，但它们的整体生物学相关性仍然难以捉摸。直到最近才开始研究RNA中G-四链体的功能。在这里，我们首次证明，RNA G-四链体结构抑制真核细胞中的体内翻译。我们研究了在人Zic-1锌指蛋白mRNA的59-UTR中高度保守的、生物学稳定的RNA G-四链体的功能。使用双荧光素酶报告基因分析，我们证明了Zic-1 RNA G-四链体抑制真核细胞内的蛋白质合成。定量RT-PCR分析证实，蛋白质合成的减少是由于翻译过程的调节，而不是转录减少的结果。Western印迹分析表明，Zic-1的表达强烈减少了73个核苷酸长的片段的UTR含有G-四链体基序。这些结构可能会添加到最近发现的mRNA非翻译区的元件中，这些元件调节它们的翻译。
Guanine-rich sequences can adopt intramolecular four-stranded structures, called G-quadruplexes. These motifs have been intensively investigated on the DNA level, but their overall biological relevance remains elusive. Only recently has research concerning the function of G-quadruplexes in RNAs commenced. Here, we demonstrate for the first time, that an RNA G-quadruplex structure inhibits translation in vivo in eukaryotic cells. We investigated the function of a highly conserved, thermodynamically stable RNA G-quadruplex in the 59-UTR of the mRNA of the human Zic-1 zinc-finger protein. Using dual luciferase reporter assay, we demonstrate that the Zic-1 RNA G-quadruplex represses protein synthesis inside eukaryotic cells. Quantitative RT-PCR assays confirmed that the reduction of protein synthesis is due to regulation of the translation process and not a consequence of reduced transcription. Western blot analysis revealed that expression of Zic-1 is strongly reduced by a 73 nucleotides-long fragment of the UTR containing the G-quadruplex motif. These structures might add to the more recently discovered elements in untranslated regions of mRNAs that regulate their translation.