lncRNA promotes apoptosis of granulosa cells by targeting the miR-543-3p/DCN/TGF-β signaling pathway in Hu sheep.

Long non-coding RNAs (lncRNAs) regulate the development of follicles and reproductive diseases, but the mechanisms by which lncRNAs regulate ovarian functions and fertility remain elusive. We profiled the expression of lncRNAs in ovarian tissues of Hu sheep with different prolificacy and identified 21,327 lncRNAs. Many of the lncRNAs were differentially expressed in different groups. We further characterized an lncRNA that was predominantly expressed in the ovaries of the low prolificacy Fec (LPB+) group and mainly present in granulosa cells (GCs), and the expression of this lncRNA decreased during follicular development, which we named follicular development-associated lncRNA (). Next, we found that directly binds miR-543-3p, and decorin () was identified as a target of miR-543-3p. overexpression promoted GC apoptosis through increased expression of , which could be attenuated by miR-543-3p. Furthermore, miR-543-3p increased and reduced the expression of transforming growth factor-β (TGF-β) pathway-related genes, including and inhibin beta A (), which were upregulated upon silencing. Our results demonstrated that sponges miR-543-3p in GCs and prevents miR-543-3p from binding to the 3' UTR, resulting in transactivation and TGF-β pathway inhibition and promotion of GC apoptosis in Hu sheep. These findings provide insights into the mechanisms underlying prolificacy in sheep.