Critical regulation of miR-200/ZEB2 pathway in Oct4/Sox2-induced mesenchymal-to-epithelial transition and induced pluripotent stem cell generation
Critical regulation of miR-200/ZEB2 pathway in Oct4/Sox2-induced mesenchymal-to-epithelial transition and induced pluripotent stem cell generation
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miR-200/ZEB2 通路在 Oct4/Sox2 诱导的间充质到上皮转化和诱导多能干细胞生成中的关键调控
DOI：
10.1073/pnas.1212769110
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发表时间：
2013-02-19
影响因子：
11.1
通讯作者：
Kang, Jiuhong
中科院分区：
文献类型：
--
作者：
Wang, Guiying;Guo, Xudong;Kang, Jiuhong
成纤维细胞可以通过应用转录因子八聚体结合蛋白4（Oct 4）、含SRY盒基因2（Sox 2）、Kruppel样因子4（Klf 4）和c-骨髓细胞瘤病癌基因（c-Myc）（OSKM）重编程为诱导多能干细胞（iPSC），但潜在的机制仍不清楚。我们发现外源性Oct 4和Sox 2可以分别与miR-141/200 c和miR-200 a/B/429簇的启动子区结合，并在OSKM诱导的重编程过程中诱导miR-200家族的转录激活。用特异性抑制剂功能性抑制miR-200显著抑制OSKM引起的间充质-上皮转化（MET，成纤维细胞重编程为iPSC的早期事件）和iPSC生成，而miR-200的过表达促进MET和iPSC生成。机制研究表明，miR-200 s通过直接靶向锌指E-box结合同源框2（ZEB 2）的3′ UTR，显著抑制ZEB 2的表达，直接抑制ZEB 2可以模拟miR-200 s对iPSC生成和MET过程的影响。此外，miR-200在iPSC生成过程中的作用可以被ZEB 2过表达阻断。总之，我们的研究结果不仅揭示了miR-200家族成员是Oct 4/Sox 2重编程因子的独特介导者，而且还证明了miR-200/ZEB 2通路是Oct 4/Sox 2在早期诱导体细胞重编程的关键机制之一。
Fibroblasts can be reprogrammed to induced pluripotent stem cells (iPSCs) by application of transcription factors octamer-binding protein 4 (Oct4), SRY-box containing gene 2 (Sox2), Kruppel-like factor 4 (Klf4), and c-Myelocytomatosis oncogene (c-Myc) (OSKM), but the underlying mechanisms remain unclear. Here, we report that exogenous Oct4 and Sox2 can bind at the promoter regions of mir-141/200c and mir-200a/b/429 cluster, respectively, and induce the transcription activation of miR-200 family during the OSKM-induced reprogramming. Functional suppression of miR-200s with specific inhibitors significantly represses the OSKM-caused mesenchymal-to-epithelial transition (MET, an early event in reprogramming of fibroblasts to iPSCs) and iPSC generation, whereas overexpression of miR-200s promotes the MET and iPSC generation. Mechanistic studies showed that miR-200s significantly repress the expression of zinc finger E-box binding homeobox 2 (ZEB2) through directly targeting its 3′ UTR and direct inhibition of ZEB2 can mimic the effects of miR-200s on iPSC generation and MET process. Moreover, the effects of miR-200s during iPSC generation can be blocked by ZEB2 overexpression. Collectively, our findings not only reveal that members of the miR-200 family are unique mediators of the reprogramming factors Oct4/Sox2, but also demonstrate that the miR-200/ZEB2 pathway as one critical mechanism of Oct4/Sox2 to induce somatic cell reprogramming at the early stage.