Zhang Shiqiang, Xie Youlong, Cao Hongxia, Wang Huayan
College of Veterinary Medicine, Shaanxi Center of Stem Cells Engineering & Technology, Northwest A&F University, Yangling, Shaanxi 712100, China.
Cell Death Dis. 2017 Aug 31;8(8):e3027. doi: 10.1038/cddis.2017.426.
Previous evidences have proved that porcine-induced pluripotent stem cells (piPSCs) could be induced to distinctive metastable pluripotent states. This raises the issue of whether there is a common transcriptomic profile existing among the piPSC lines at distinctive state. In this study, we performed conjoint analysis of small RNA-seq and mRNA-seq for three piPSC lines which represent LIF dependence, FGF2 dependence and LFB2i dependence, respectively. Interestingly, we found there are 16 common microRNAs which potentially target 13 common mRNAs among the three piPSC lines. Dual-luciferase reporter assay validated that miR-370, one of the 16 common microRNAs, could directly target the 3'UTR of LIN28A. When the differentiation occurred, miR-370 could be activated in piPSCs and switched off the expression of LIN28A. Ectopic expression of miR-370 in piPSCs could reduce LIN28A expression, decrease the alkaline phosphatase activity, slow down the proliferation, and further cause the downregulation of downstream pluripotent genes (OCT4, SOX2, NANOG, SALL4 and ESRRB) and upregulation of differentiation relevant genes (SOX9, JARID2 and JMJD4). Moreover, these phenotypes caused by miR-370 could be rescued by overexpressing LIN28A. Collectively, our findings suggest that a set of common miRNA-mRNA interactions exist among the distinct piPSC lines, which orchestrate the self-renewal and differentiation of piPSCs independent of their metastable pluripotent states.
先前的证据已证明，猪诱导多能干细胞（piPSCs）可被诱导进入不同的亚稳定多能状态。这就引发了一个问题，即在不同状态的piPSC系之间是否存在共同的转录组特征。在本研究中，我们对分别代表LIF依赖、FGF2依赖和LFB2i依赖的三个piPSC系进行了小RNA测序和mRNA测序的联合分析。有趣的是，我们发现这三个piPSC系中有16个共同的微小RNA，它们可能靶向13个共同的mRNA。双荧光素酶报告基因检测验证了这16个共同微小RNA之一的miR-370可以直接靶向LIN28A的3'UTR。当发生分化时，miR-370可在piPSCs中被激活，并关闭LIN28A的表达。在piPSCs中异位表达miR-370可降低LIN28A的表达，降低碱性磷酸酶活性，减缓增殖，并进一步导致下游多能基因（OCT4、SOX2、NANOG、SALL4和ESRRB）的下调以及分化相关基因（SOX9、JARID2和JMJD4）的上调。此外，过表达LIN28A可挽救由miR-370引起的这些表型。总的来说，我们的研究结果表明，在不同的piPSC系之间存在一组共同的miRNA-mRNA相互作用，它们协调piPSCs的自我更新和分化，而与它们的亚稳定多能状态无关。
