Long noncoding RNA MALAT1 promotes osterix expression to regulate osteogenic differentiation by targeting miRNA-143 in human bone marrow-derived mesenchymal stem cells
Long noncoding RNA MALAT1 promotes osterix expression to regulate osteogenic differentiation by targeting miRNA-143 in human bone marrow-derived mesenchymal stem cells
复制标题
DOI：
10.1002/jcb.26907
复制
发表时间：
2018-08-01
影响因子：
4
通讯作者：
Chen, Xiaodong
中科院分区：
文献类型：
--
作者：
Gao, Yuan;Xiao, Fei;Chen, Xiaodong
人骨髓间充质干细胞(HBMSCs)的成骨分化是人骨形成所必需的，越来越多的证据表明，长非编码RNA(LncRNAs)在hBMSC成骨分化中起着重要作用。MALAT1通常被认为是一种与肿瘤相关的lncRNA，但其在间充质干细胞分化中的作用尚不清楚。在本研究中，我们旨在研究MALAT1是否通过海绵miR-143来调节Osterix(OSX)的表达，以促进hBMSC的成骨分化。首先，我们发现MALAT1在骨质疏松症患者的hBMSCs中的表达明显降低，而miR-143的表达则相反。此外，hBMSCs经成骨诱导后，MALAT1表达增加，miR-143表达降低。然后，我们利用短发夹状RNA对MALAT1进行了基因敲除，结果显示hBMSC的成骨分化显著降低，表明MALAT1是hBMSCs成骨分化的正向调节因子。此外，通过荧光素酶检测，我们发现MALAT1可以直接与miR-143结合并负调控其表达。同样，miR-143可以直接与OSX 3-UTR上的靶点结合，进而抑制OSX的表达。MALAT1基因敲除可降低OSX基因的表达，联合应用miR-143抑制剂可恢复OSX基因的表达。在MALAT1过表达的hBMSCs中，OSX的表达增加，而miR-143模拟物逆转了OSX的表达。此外，OSX沉默降低了miR-143抑制剂诱导的ALP、OCN和OPN mRNA的表达。综上所述，我们的研究结果表明，MALAT1通过靶向miR-143来调节OSX的表达；因此，它被认为是hBMSC成骨分化的积极调节因子。
Osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) is essential for the human bone formation, and emerging evidence shows that long non-coding RNAs (lncRNAs) play important roles in hBMSC osteogenic differentiation. MALAT1 is often regarded as a tumor-related lncRNA, but its function in mesenchymal stem cell differentiation remains to be defined. In this study, we aimed to investigate whether MALAT1 regulates Osterix (Osx) expression by sponging miR-143 to promote hBMSC osteogenic differentiation. Firstly, we found that the expression of MALAT1 was much lower in hBMSCs from osteoporosis patients and miR-143 was contrarily higher. In addition, MALAT1 expression increased, and miR-143 decreased when hBMSCs were treated with osteogenic induction. Then, we used short hairpin RNAs to knockdown MALAT1, and the results showed that hBMSC osteogenic differentiation decreased significantly, indicating that MALAT1 is a positive regulator of osteogenic differentiation in hBMSCs. Furthermore, by luciferase assays, we found that MALAT1 could directly bind to miR-143 and negatively regulate its expression. Similarly, miR-143 could directly bind to the target site on the Osx 3-UTR and then inhibit Osx expression. Knockdown of MALAT1 decreased Osx expression, and co-transfection of miR-143 inhibitor could rescue Osx mRNA expression. While Osx expression was increased in MALAT1-overexpressing hBMSCs, it was reversed by the miR-143 mimics. Moreover, Osx silencing decreased ALP, OCN, and OPN mRNA expression induced by the miR-143 inhibitor. Altogether, our findings suggest that MALAT1 acts to regulate Osx expression through targeting miR-143; thus, it is considered as a positive regulator in hBMSC osteogenic differentiation.