Identification of conservative microRNAs in Saanen dairy goat testis through deep sequencing

MicroRNA (miRNA) is a kind of small non-coding RNA molecules that function as important gene expression regulators by targeting messenger RNAs for post-transcriptional endonucleolytic cleavage or translational inhibition. In this study, small RNA libraries were constructed based on adult dairy goat testicular tissues and sequenced using the Illumina high-throughput sequencing technology. Blasted to miRNAs of cow and sheep in miRBase 19.0, 373 conserved miRNAs were identified in dairy goat testis and 91 novel paired-miRNAs were found. Expression of miRNAs in the dairy goat testis (miR-10b, miR-126-3p, miR-126-5p, miR-34c, miR-449b and miR-1468) was confirmed by qRT-PCR. In addition, the 128 conserved miRNAs were found by comparing the miRNA expression profiles in dairy goat testis with those in cow and mouse, which all might be involved in dairy goat testis development and meiosis. This study reveals the first miRNA profile related to the biology of testis in the dairy goat. The characterization of these miRNAs could contribute to a better understanding of the molecular mechanisms of reproductive physiology and development in the dairy goat.