RESUMEN
MicroRNAs (miRNAs) are widely expressed in different mammalian tissues and exert their biological effects through corresponding target genes. miRNA target genes can be rapidly and efficiently identified and screened by combining bioinformatics prediction and experimental validation. To investigate the possible molecular regulatory mechanisms involving miRNAs during uterine involution in postpartum ewes, we used Illumina HiSeq sequencing technology to screen for the number and characteristics of miRNAs in faster uterine involution and normal uterine involution group. A total of 118 differentially expressed miRNAs, including 33 known miRNAs and 85 new miRNAs, were identified in the hypothalamic library, whereas 54 miRNAs, including 5 known miRNAs and 49 new miRNAs, were identified in the uterine library. Screening with four types of gene prediction software revealed 73 target genes associated with uterine involution, and subsequently, GO annotation and KEGG pathway analysis were performed. The results showed that, in the hypothalamic-uterine axis, uterine involution in postpartum ewes might primarily involve two miRNA-target gene pairs, namely, miRNA-200a-PTEN and miRNA-133-FGFR1, which can participate in GnRH signal transduction in the upstream hypothalamus and in the remodeling process at the downstream uterus, through the PI3K-AKT signaling pathway to influence the recovery of the morphology and functions of the uterus during the postpartum period in sheep. Therefore, identification of differentially expressed miRNAs in this study fills a gap in the research related to miRNAs in uterine involution in postpartum ewes and provides an important reference point for a comprehensive understanding of the molecular mechanisms underlying the regulation of postpartum uterine involution in female livestock.
RESUMEN
To examine the possible miRNA molecular regulatory mechanisms during maternal uterine involution after delivery, we selected ovary and uterus tissues that are structurally connected as experimental materials. We employed Illumina HiSeq sequencing to screen and analyze the quantity and characteristics of miRNA in postpartum ewes in the methylergometrine-treated group and physiological saline control group. Results showed that 16 miRNAs were identified in the ovary libraries, including 4 known miRNAs and 12 novel miRNAs. In the uterus libraries, 54 miRNAs were identified, which included 5 known miRNAs and 49 novel miRNAs. At the same time, target gene prediction, GO annotation, and KEGG signaling pathway enrichment analysis were employed. We found that maternal uterine involution after delivery may involve two miRNA-target gene pairs, i.e., miRNA-200a-ZEB1 and YAP1. The YAP1/Hippo signaling pathway is used to construct an ovary-uterine axial regulatory mechanism to regulate the restoration of postpartum maternal uterine morphology and function. In view of this, the identification of miRNAs with significant differences in this study fills a gap in research on miRNAs associated with regulation of postpartum uterine recovery in ewes and provided an important reference for comprehensive understanding and in-depth research on the regulatory molecular network mechanism for postpartum uterine involution in small ruminants.