Expression profiles of MicroRNAs from multiple lumbar spine in sheep.

The formation of the spine is a critical stage of mammalian development. The increase of the number of individual axons affects its performance, especially in meat production. To understand the role of miRNAs in sheep vertebrae development, the purpose of this article is to screen candidate microRNAs (miRNAs) associated with sheep spine development. MicroRNAs (miRNAs) are a rich family of small regulatory RNAs that negatively regulate gene expression at the post-transcriptional level. In this study, we used high-throughput sequencing techniques to analyze the microRNAs (miRNAs) expression profiles of L6 (6 lumbar vertebrae) and L7 (7 lumbar vertebrae) in sheep. A total number of 223 miRNAs were detected in the two libraries, and a total of 150 and 148 conserved miRNAs were obtained in L6 and L7, respectively. A total of 5 miRNAs expression differences in L6 compared to L7 (P < 0.05). Of the five obviously differently expressed miRNAs, four miRNAs were down-regulated in the L6 of sheep, and one was up-regulated. In order to further explore the functions of these miRNAs, we predicted the target genes of these differently expressed miRNAs, and obtained 1298 target genes. At the same time, NDRG2 gene, targeted by novel miR-391, which possible plays an important role in the development of the spine. Linkage-integration analysis method was used to construct the interaction network of spinal-associated miRNA and its hypothesized target. In summary, this study provides valuable resources for the transcriptome of multiple vertebral traits in sheep.