MicroRNA-214 regulates smooth muscle cell differentiation from stem cells by targeting RNA-binding protein QKI.
MicroRNA-214 regulates smooth muscle cell differentiation from stem cells by targeting RNA-binding protein QKI.
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MicroRNA-214 通过靶向 RNA 结合蛋白 QKI 调节平滑肌细胞从干细胞分化
DOI：
10.18632/oncotarget.15189
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发表时间：
2017-03-21
期刊：
影响因子：
--
通讯作者：
Zhang L
中科院分区：
文献类型：
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作者：
Wu Y;Li Z;Yang M;Dai B;Hu F;Yang F;Zhu J;Chen T;Zhang L
MicroRNA-214(miR-214)最近被报道调节血管生成和胚胎干细胞(ESCs)的分化。然而，其在血管平滑肌细胞(VSMCs)分化为ESCs中的功能作用却知之甚少。在本研究中，我们评估了miR-214及其靶基因在VSMCs分化中起重要作用的假说。将小鼠胚胎干细胞接种于包被胶原的培养瓶中，在分化培养液中培养2~8天，使其分化为VSMCs。MIR-214在VSMCs分化过程中显著上调。在ESCs分化过程中，MIR-214过表达和基因敲除分别显著促进和抑制VSMCs特异性基因的表达。重要的是，miR-214在ESCs中的过表达促进了体内VSMCs的分化。震颤(QKI)被预测为miR-214的主要靶点之一，而miR-214对其进行负调控。荧光素酶分析显示miR-214在分化ESCs过程中显著抑制了野生型，而不是突变型的QKI-3-UTR-荧光素酶活性，进一步证实了miR-214对QKI基因表达的负调控作用。在机制上，我们的数据表明miR-214通过抑制QKI调控VSMCs向ESCs分化的过程中VSMCs基因的表达。我们进一步证明，QKI通过转录抑制和直接结合SRF、MEF2C和MYOCD基因的启动子来下调SRF、MEF2C和MYOCD基因的表达。综上所述，我们揭示了miR-214在ESC-VSMC分化中的核心作用，并成功地将QKI确定为miR-214介导的VSMC分化的功能调控靶点。
MicroRNA-214(miR-214) has been recently reported to regulate angiogenesis and embryonic stem cells (ESCs) differentiation. However, very little is known about its functional role in vascular smooth muscle cells (VSMCs) differentiation from ESCs. In the present study, we assessed the hypothesis that miR-214 and its target genes play an important role in VSMCs differentiation. Murine ESCs were seeded on collagen-coated flasks and cultured in differentiation medium for 2 to 8 days to allow VSMCs differentiation. miR-214 was significantly upregulated during VSMCs differentiation. miR-214 overexpression and knockdown in differentiating ESCs significantly promoted and inhibited VSMCs -specific genes expression, respectively. Importantly, miR-214 overexpression in ESCs promoted VSMCs differentiation in vivo. Quaking (QKI) was predicted as one of the major targets of miR-214, which was negatively regulated by miR-214. Luciferase assay showed miR-214 substantially inhibited wild type, but not the mutant version of QKI-3-UTR-luciferase activity in differentiating ESCs, further confirming a negative regulation role of miR-214 in QKI gene expression. Mechanistically, our data showed that miR-214 regulated VSMCs gene expression during VSMCs differentiation from ESCs through suppression of QKI. We further demonstrated that QKI down-regulated the expression of SRF, MEF2C and Myocd through transcriptional repression and direct binding to promoters of the SRF, MEF2c and Myocd genes. Taken together, we have uncovered a central role of miR-214 in ESC-VSMC differentiation, and successfully identified QKI as a functional modulating target in miR-214 mediated VSMCs differentiation.