MicroRNA profiling during neural differentiation of induced pluripotent stem cells

MicroRNAs (miRNA) play an essential role in the regulation of gene expression, influence signaling networks responsible for several cellular processes like differentiation of pluripotent stem cells. Despite several studies on the neurogenesis process, no global analysis of microRNA expression during differentiation of induced pluripotent stem cells (iPSC) to neuronal stem cells (NSC) has been done. Therefore we compared the profile of microRNA expression in iPSC lines and in NSC lines derived from them, using microarray-based analysis. Two different protocols for NSC formation were used: direct and two-step via neural rosette formation. We confirmed the new associations of previously described miRNAs in regulation of NSC differentiation from iPSC. We discovered upregulation of miR-10 family, miR-30 family and miR-9 family and downregulation of miR-302 and miR-515 family. Moreover we showed that miR-10 family play a crucial role in the negative regulation of genes expression belonging to signaling pathways involved in neural differentiation: WNT signaling pathway, focal adhesion, signaling pathways regulating pluripotency of stem cells. We conducted differentiation of human induced pluripotent stem cells into neural stem cells. Then we carried out global miRNA expression analysis using the Affymetrix platform. We profiled the miRNAs which are crucial regulators of neural differentiation. We not only confirmed the involvement of previously described miRNAs characteristic for transition from ES to NSC: mir-302 family, hsa-miR-125b, hsa-miR-9, let-7, but we also pointed out others, which may be characteristic for iPSC to NSC transition.