MicroRNAs expression in hypothalamic-pituitary-gonadal axis in goat

Reproduction is an event that requires the coordination of peripheral organs with the central nervous system, each event is accompanied by positive and negative hormonal regulation along the Hypothalamic\Pituitary\Gonadal (HPG) axis. MicroRNAs (miRNAs), a class of small non\coding RNA molecules, play important roles in gene expressions by targeting messenger RNAs for post\transcriptional cleavage or translational inhibition, affecting physiology in mammals. In order to better understand molecular pathways involved in HPG axis regulation, we evaluate the transcriptomic and miRNA profile changes in hypothalamus, pituitary and ovary from 3 Saanen goats using Illumina high\throughput technology. Reads were mapped on the Capra hircus reference genome and expression levels of both coding and non coding RNAs were assessed. We found 818 miRNAs belonging to known (436) and novel (382) classes, ti7 of which are differen tially expressed in the three tissues. Transcriptomic profiling revealed 2,223, genes that were differentially expressed between hypothalamus and pituitary, 2,117 between pituitary and ovary and 3,823 between hypothalamus and ovary. This study reveals for the first time a complete large and small RNA profile of the HPG axis in goat. The characterization of these RNAs could contribute to a better understanding of the molecular mechanisms of reproductive physiology and development in this species.