Identification of Novel and Differentially Expressed MicroRNAs in the Ovaries of Laying and Non-Laying Ducks

MicroRNAs （miRNAs）, which post-transcriptionally regulate gene expression by binding to the 3′untranslated region of mRNAs to either inhibit or enhance translation, are involved in diverse biological processes. The use of high-throughput Solexa sequencing plays important roles in the discovery of miRNAs. In this study, we used high-throughput Solexa sequencing to identify novel duck miRNAs and compare the miRNA expression profiles in laying and non-laying duck ovaries. Using a bioinformatic analysis, we discovered 86 potential duck miRNAs similar to known chicken miRNAs and 43 unique sequences that matched known miRNAs of other species. We also found that miRNA variations and isoforms were widespread in our two RNA libraries, with most of the variations occurring in the 3′region of the miRNAs. Furthermore, we detected 55 miRNAs that exhibited significant expression differences between laying and non-laying ducks. Gene ontology （GO） and kyoto encyclopedia of genes and genomes （KEGG） enrichment analyses of the potential targets of the differentially expressed miRNAs indicated these miRNAs may play key roles in the egg laying process. Finally, we confirmed the differential expression of 5 miRNAs in the laying and non-laying samples by qRT-PCR. Cumulatively, our work provides the first look at the miRNA expression profile of the duck ovary and provides novel insight into the roles of miRNAs in egg laying and reproduction.

Interferon-γ Alters the Immune-related miRNA Expression of Microvesicles Derived from Mesenchymal Stem Cells

Increasing studies have demonstrated that interferon gamma（IFN-γ）,which serves as a critical inflammatory cytokine,is essential to induce the immunosuppressive effects of mesenchymal stem cells（MSCs）.However,the mechanisms underlying the enhanced immunosuppressive effects of IFN-γ-stimulated MSCs（γMSCs） are not fully understood.MSC-derived microvesicles（MSC-MVs） have been viewed as potential pivotal mediators of the immunosuppressive effects of MSCs.Moreover,micro RNAs（miR NAs） are important regulators of immunological processes and can be shuttled from cell to cell by MVs.The aim of our study was to analyze the the mi RNA expression signature of MVs derived from γMSCs（γMSC-MVs）,which may provide better understanding of the immunosuppressive property of their parent cells.Through mi RNA microarray and bioinformatics analysis,we found 62 significantly differentially expressed miR NAs（DEMs） in γMSC-MVs compared with MSC-MVs.And the potential target genes and signaling pathways regulated by DEMs were predicted and analyzed.Interestingly,many DEMs and predicted signaling pathways had been demonstrated to be involved in immunoregulation.Furthermore,the network between immunoregulation-related pathways and relevant DEMs was constructed.Collectively,our research on the mi RNA repertoires of γMSC-MVs not only provides new perspectives into the mechanisms underlying the enhanced immunosuppressive property of γMSCs,but also paves the way to clinical application of these potent organelles in the future.