P1003 MiRNAs expression profiling of myostatin transgenic and wild-type littermate mice by Solexa deep sequencing

miRNAs are a class of short, non-coding RNA molecules that reportedly play a central role in regulating post-transcriptional gene expression during embryonic stem cell development, myogenesis, adipogenesis, fat metabolism, and glucose homeostasis. For assessment of the effect of loss of myostatin signaling on gene expression in skeletal muscle, RNA from post-developmental myostatin transgenic and wild-type littermate mice were analyzed with Solexa deep sequencing. Sequencing data were analyzed using miRDeep software V. 2.1.2. Four hundred sixty-one mature known miRNAs were identified, out of which 57 miRNAs were found to be differentially expressed. Expression pattern demonstrated that Mmu-miR-22 was most abundant; miRNA, mmu-miR-133a, and mmu-miR-378a were abundant and significantly differentially expressed miRNAs. Sixty-nine novel miRNAs were also identified, out of which 3 NMu-1, NMu-14, and NMu-36 accounted higher read count. For these 3 novel miRNAs and 5 known miRNAs, the expression profiling was done for using Q-PCR analysis. Out of 57 differentially expressed miRNAs, the 20 most abundant miRNAs were selected for target prediction and pathway analysis. Four thousand five hundred eighty-three targets were identified, out of which FST, SMAD3, TGFBR1, ACVR1a, and MEF2c genes, which plays vital role in MSTN signaling, were found to be targeted by miR-101, miR-425, miR-199a, and miR-582 in TGFb-signaling pathway, which activates MSTN signaling. Hence, these miRNAs could prove crucial candidate miRNAs in skeletal muscle development. In conclusion, the present study proffers an initial miRNA transcriptome profile in skeletal muscle development of transgenic and control mice. Findings aided identification of miRNA and their targets, which can possibly contribute to skeletal muscle development. Information generated in this study can be further used to investigate the role of identified miRNAs and their targets in regulation of skeletal muscle development.