lncRNA-FMR6 directly binds SAV1 to increase apoptosis of granulosa cells in premature ovarian failure

BACKGROUND: A regulatory mechanism of lncRNA binding to protein has been detected in premature ovarian failure (POF). Therefore, this study was expected to illustrate the mechanism of lncRNA-FMR6 and SAV1 regulating POF. METHODS: Follicular fluid and ovarian granulosa cells (OGCs) from POF patients and healthy volunteers were collected. Using RT-qPCR and western blotting, lncRNA-FMR6 and SAV1 expression were detected. KGN cells were cultured, and the subcellular localization analysis of lncRNA-FMR6 was carried out. In addition, KGN cells were treated with lncRNA-FMR6 knockdown/overexpression or SAV1 knockdown. Then, cell optical density (proliferation), apoptosis rate, Bax and Bcl-2 mRNA expression were explored by CCK-8, caspase-3 activity, flow cytometry and RT-qPCR analysis. By performing RIP and RNA pull-down experiments, the interactions among lncRNA-FMR6 and SAV1 was investigated. RESULTS: Up-regulation of lncRNA-FMR6 was shown in follicular fluid and OGCs of POF patients, and ectopic overexpression of lncRNA-FMR6 promoted KGN cells apoptosis and inhibited proliferation. lncRNA-FMR6 was localized in the cytoplasm of KGN cells. SAV1 bounding to lncRNA-FMR6 was negatively regulated by lncRNA-FMR6, and was down-regulated in POF. SAV1 knockdown promoted KGN cells proliferation and inhibited apoptosis, and partially eliminated the effect of lncRNA-FMR6 low expression on KGN cells. CONCLUSION: Overall, lncRNA-FMR6 accelerates POF progression by binding to SAV1.