Integrated analysis of miRNA and mRNA expression profiles in 2-, 6- and 12-month-old Small Tail Han Sheep testes to explore the regulation in testis development. Integrated analysis of miRNA and mRNA expression profiles in 2-, 6- and 12-month-old Small Tail Han Sheep testes to explore the regulation in testis development

The semen of Small Tail Han Sheep has characteristics of high yield, high density, and good motility. To reveal the key miRNAs, mRNAs and miR-Targets regulatory mechanisms in Small Tail Han Sheep testes development, integrated analysis of miRNA and mRNA expression profiles in 2-, 6-, and 12-month-old testes were investigated by RNA-seq technology and bioinformatics methods. As the results shown: 630, 102, and 322 differentially expressed (DE) mRNAs; 5, 1 and 4 DE known miRNAs; 132, 105 and 24 DE novel miRNAs were identified in 2- vs 6-month-old, 6- vs 12-month-old, and 2- vs 12-month-old testes, respectively. GO and pathway analysis showed: in 2- vs 6-month-old testes, DE mRNAs were mainly involved in sexual maturation process and the DE mRNAs were mainly involved in multiple metabolism and biosynthesis pathways; in 6- vs 12-month-old testes, DE mRNAs were mainly involved in metabolism and translation processes, and the most significant pathway that DE mRNAs involved in was ribosome pathway; in 2- vs 12-month-old testes, DE mRNAs were mainly involved in metabolism and physiological processes, and DE mRNAs were mainly involved in multiple metabolism and biosynthesis pathways. Subsequently, 76, 11 and 1 DE miR-Targets were identified in 2- vs 6-month-old, 2- vs 12-month-old, and 6- vs 12-month-old testes, respectively. 3 miR-Target regulatory networks were constructed based on these miR-Targets, which helped to elucidate the regulatory metabolism in Small Tail sheep testes development. Finally, 6 miRNAs and 7 mRNAs were selected to validate the RNA-seq data by RT-PCR. Overall design: Investigation of mRNA and miRNA expression profiles in 2-, 6-, and 12-month-old Small Tail Han Sheep testes.