MicroRNA-373 induces expression of genes with complementary promoter sequences
MicroRNA-373 induces expression of genes with complementary promoter sequences
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DOI：
10.1073/pnas.0707594105
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发表时间：
2008-02-05
影响因子：
11.1
通讯作者：
Dahiya, Rajvir
中科院分区：
文献类型：
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作者：
Place, Robert F.;Li, Long-Cheng;Dahiya, Rajvir
近期研究表明，微小RNA（miRNA）通过抑制翻译或引导互补信使RNA（mRNA）的序列特异性降解来调控基因表达。在此，我们报道了miRNA可能也具有诱导基因表达功能的新证据。通过在计算机上对基因启动子进行扫描，寻找与已知miRNA互补的序列，我们在E - 钙黏蛋白的启动子中确定了一个假定的miR - 373靶位点。将miR - 373及其前体发夹RNA（pre - miR - 373）转染到PC - 3细胞中，很容易诱导E - 钙黏蛋白表达。基因敲低实验证实，pre - miR - 373对E - 钙黏蛋白的诱导需要miRNA成熟蛋白Dicer。进一步分析显示，在其启动子内具有假定的miR - 373靶位点的含冷休克结构域蛋白C2（CSDC2），在对miR - 373和pre - miR - 373的反应中也很容易被诱导。此外，在miR - 373转染后，在E - 钙黏蛋白和CSDC2启动子处都检测到RNA聚合酶II的富集。miR - 373的错配突变表明基因诱导对miR - 373序列具有特异性。启动子特异性双链RNA的转染显示，miR - 373对E - 钙黏蛋白和CSDC2的同时诱导需要两个启动子中的miRNA靶位点。总之，我们已经鉴定出一种靶向启动子序列并诱导基因表达的miRNA。这些发现揭示了miRNA调控基因表达的一种新模式。
Recent studies have shown that microRNA (miRNA) regulates gene expression by repressing translation or directing sequence-specific degradation of complementary mRNA. Here, we report new evidence in which miRNA may also function to induce gene expression. By scanning gene promoters in silico for sequences complementary to known miRNAs, we identified a putative miR-373 target site in the promoter of E-cadherin. Transfection of miR-373 and its precursor hairpin RNA (pre-miR-373) into PC-3 cells readily induced E-cadherin expression. Knockdown experiments confirmed that induction of E-cadherin by pre-miR-373 required the miRNA maturation protein Dicer. Further analysis revealed that cold-shock domain-containing protein C2 (CSDC2), which possesses a putative miR-373 target site within its promoter, was also readily induced in response to miR-373 and pre-miR-373. Furthermore, enrichment of RNA polymerase II was detected at both E-cadherin and CSDC2 promoters after miR-373 transfection. Mismatch mutations to miR-373 indicated that gene induction was specific to the miR-373 sequence. Transfection of promoter-specific dsRNAs revealed that the concurrent induction of E-cadherin and CSDC2 by miR-373 required the miRNA target sites in both promoters. In conclusion, we have identified a miRNA that targets promoter sequences and induces gene expression. These findings reveal a new mode by which miRNAs may regulate gene expression.