microRNA expression profiling in neural stem cells differentiated from mouse embryonic carcinoma P19 cells

microRNAs (or miRNAs) are small noncoding RNAs (21 to 25 nucleotides) that are processed from longer hairpin RNA precursors and are believed to be involved in a wide range of developmental and cellular processes, by either repressing translation or triggering mRNA degradation (RNA interference). Expression analysis of miRNAs is necessary to understand their complex role in the regulation of gene expression during the development, differentiation and proliferation of cells. Here we report on the expression profile analysis of miRNAs in mouse P19 embryonic carcinoma (EC) cell，which were used to get efficient derivation of a high percentage (∼95%) of neural stem cells from in N2B27 serum-free medium, in vitro simulated the process in vivo neural induction.The data presented here indicate marked changes in the expression of miRNAs between the P19 EC cell and the neural stem cells derived from them. Among ~160 mouse miRNAs, 37 miRNAs are increased (2.0-fold up-regulated) and 41 miRNAs are decreased (2.0-fold down-regulated) in their expression level after the differentiation. MiR-124a is dramatically up-regulated (above 20-fold). However, miR-302 cluster and miR290-295 cluster are down-regulated strongly. Further analyses show that some important factors, such as Oct4 and Sox2, are involved in the regulation system of these miRNAs. In brief, our results might contribute to a greater understanding of the many biological events in neural induction of early mouse embryos regulated by miRNAs. Keywords: microRNA, mouse, neural differentiation we employed a method established by Xia et al. to get a high percentage (~95%) of efficient derivation of neural stem cells from P19 EC cell in N2B27 serum-free medium by in vitro simulating the process of in vivo neural induction.We used microarray to monitor mouse miRNA expression profile in the course of their neuronal differentiation.For each sample, two independent small RNA libraries (biological replications) were generated and two independent reverse transcriptions/amplifications/hybridizations (technical replications) were performed for each library. undifferentitated P19 replicate three times while differentitated P19 replicate twice.