Comparative microRNA Transcriptome in Domestic Goats Reveals Adaptation to High Altitude

High-altitude adaptation is a representative example of vertebrates getting adapted to harsh and extreme environments. To investigate the miRNA expression alterations of goats that were induced by high altitude stress, we performed comparative miRNA transcriptome analysis on six hypoxia-sensitive tissues (heart, kidney, liver, lung, skeletal muscle and spleen) in two indigenous goat populations from distinct altitudes (600 m and 3000 m). We obtained the expression of 1391 mature miRNAs and identified 138 differentially expressed miRNAs between altitudes. Combined with tissue specificity analysis, we illustrated alterations of expression levels between altitudes and among tissues, which suggested the coexisting tissue-specific and tissue-conserved mechanism for hypoxia adaptation. Notably, the interplay between DE miRNA and DE target genes strongly indicated post-transcriptional regulation in HIF-1 signaling pathway, insulin signaling pathway and p53 signaling pathway, which might play a significant role in high altitude adaptation in domestic goats. These results provide insights into the complicated miRNA expression pattern and regulatory mechanism of high altitude adaptation in domestic goats. Overall design: Six organs (heart,liver,spleen,lung,kidney and muscle) miRNA profiles of high- and their low-altitude goat were generated by deep sequencing,in triplicate using Illumina Hiseq2500 .