MicroRNA‐3061 downregulates the expression of PAX7/Wnt/Ca2+ signalling axis genes to induce premature ovarian failure in mice

Abstract The in‐depth mechanisms of microRNA regulation of premature ovarian failure (POF) remain unclear. Crispr‐cas9 technology was used to construct transgenic mice. The qPCR and Western blot was used to detect the expression level of genes. H&E staining were used to detect ovarian pathological phenotypes. We found that the expression levels of microRNA‐3061 were significantly higher in ovarian granulosa cells (OGCs) of POF mouse models than in controls. The miR‐3061 +/− /AMH‐Cre +/− transgenic mice manifested symptoms of POF. RNA‐Seq and luciferase reporter assay confirmed that the PAX7 was one of the target genes negatively regulated by microRNA‐3061 (miR‐3061–5p). Moreover, PAX7 mediated the expression of non‐canonical Wnt/Ca 2+ signalling pathway by binding to the motifs of promoters to stimulate the transcriptional activation of Wnt5a and CamK2a. In contrast, specific knock‐in of microRNA‐3061 in OGCs significantly downregulated the expression levels of PAX7 and inhibited the expression of downstream Wnt/Ca 2+ signalling pathway. We also discerned a correlation between the expression levels of mRNAs of the Wnt/Ca2+ signalling pathway and the levels of E2 and FSH in POF patients by examining gene expression in the follicular fluid‐derived exosomes of women. We confirmed that overexpression of microRNA‐3061 induced proliferative inhibition of OGCs and ultimately induced POF in mice by suppressing the transcription factor PAX7 and downregulating expression levels of its downstream Wnt/Ca 2+ signalling pathway genes.