Let-7 microRNA-mediated mRNA deadenylation and translational repression in a mammalian cell-free system
Let-7 microRNA-mediated mRNA deadenylation and translational repression in a mammalian cell-free system
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DOI：
10.1101/gad.1566707
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发表时间：
2007-08-01
影响因子：
10.5
通讯作者：
Yokoyama, Shigeyuki
中科院分区：
文献类型：
--
作者：
Wakiyama, Motoaki;Takimoto, Koji;Yokoyama, Shigeyuki
MicroRNA (miRNA) 被整合到 miRNP 复合物中，并通过与目标 mRNA 的 3'-非翻译区结合来调节转录后蛋白质表达。在这里，我们描述了无细胞系统中 let-7 miRNA 介导的翻译抑制的重述，该系统是用从过表达 miRNA 途径成分的 HEK293F 细胞制备的提取物建立的。在此系统中，翻译抑制需要帽和聚腺苷酸尾，let-7 指导目标 mRNA 的去腺苷化。我们的工作表明，含有 Argonaute 和 GW182 的 let-7 miRNP 会损害 5'-cap 和 3'-poly(A) 尾的翻译协同增强作用，导致翻译抑制。
MicroRNAs (miRNAs) are incorporated into miRNP complexes and regulate protein expression post-transcriptionally through binding to 3'-untranslated regions of target mRNAs. Here we describe a recapitulation of let-7 miRNA-mediated translational repression in a cell-free system, which was established with extracts prepared from HEK293F cells overexpressing miRNA pathway components. In this system, both the cap and poly(A) tail are required for the translational repression, and let-7 directs the deadenylation of target mRNAs. Our work suggests that let-7 miRNPs containing Argonaute and GW182 impair the synergistic enhancement of translation by the 5'-cap and 3'-poly(A) tail, resulting in translational repression.