Genome -wide transcriptome profiling in ovaries of small-tail Han sheep during the follicular and luteal phases of the oestrous cycle.

Ovarian function, the control of which is predominantly integrated by the hypothalamic-pituitary-ovarian axis, is pivotal for maintaining reproductive efficiency in sheep. To understand the regulatory mechanism of the follicular-luteal phase transition in prolific sheep, the genome-wide expression patterns of microRNAs and genes in ovarian tissue of Small Tail Han sheep were examined during the follicular and luteal phases of the oestrous cycle. Differentially expressed genes (n = 450) were identified and a total of 139 known and 72 novel miRNAs were identified in the two libraries. It is suggested that differential abundance of miR-200a, 200b and 200c may have an important role in the follicular-luteal transition. A miRNA-regulated gene expression network was created for exploring the regulation of the follicular-luteal transition and quantitative real-time PCR verified the reliability of the RNA-seq data.