Identification and Сharacteristics of Conserved miRNA in Testis Tissue from Chinese Giant Salamander (Andrias davidianus) by Deep Sequencing

Resumo

MicroRNAs (miRNAs) are a family of ∼22-nucleotide, non-coding, single-stranded RNA molecules, which are considered as key regulators of gene expression and regulate various biological processes including gonad development, differentiation and dimorphism. Although most miRNAs studied have been identified in animals, relatively limited knowledge also exist on amphibian species. Identification of the full repertoire of miRNAs in testes of Andrias davidianus would significantly increase our knowledge on miRNA physiological functions of miRNA in gonads. In this study, a small RNA library was constructed from adult A. davidianus testis tissue and sequenced using the deep sequencing. As a result, 26 401 474 clean reads was obtained, and 1340 known conserved miRNAs were identified. Additionally, expression of 12 randomly selected miRNAs was confirmed by stem-loop qRT-PCR from 5 different tissues of A. davidianus. Of them, aca-miR-99b-5p, xtr-miR-10c, and cfa-miR-363 were highly expressed in testes. Although the physiological functions of these expressed miRNAs were still not revealed, their expression patterns indicate that they are likely to play a role in growth and development of A. davidianus testes, which is needed to be further study for confirmation. The results of this study will help in gaining understanding of the role of miRNAs in the regulation of A. davidianus reproductive system.