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Updated: May 10, 2026

Lung microRNA Profiling Across the Estrous Cycle in Ozone-exposed Mice
Published on: January 7, 2019
MicroRNA-133b stimulates ovarian estradiol synthesis by targeting Foxl2
Anyi Dai1, Haixiang Sun, Ting Fang
1Reproductive Medicine Center, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, PR China.
Abstract:
Forkhead L2 (Foxl2) is expressed in ovarian granulosa cells and participates in steroidogenesis by transcriptionally regulating target genes such as steroidogenic acute regulatory protein (StAR) and CYP19A1. In this study, a direct link between microRNA-133b (miR-133b) and Foxl2-mediated estradiol release in granulosa cells was established. miR-133b was involved in follicle-stimulating hormone (FSH)-induced estrogen production. Luciferase assays confirmed that miR-133b was bound to the 3' untranslated region (3'UTR) of Foxl2 mRNA. Consistent with this finding, miR-133b overexpression reduced the Foxl2 levels. Furthermore, miR-133b inhibited Foxl2 binding to the StAR and CYP19A1 promoter sequences. These results demonstrate that miR-133b down-regulates Foxl2 expression in granulosa cells by directly targeting the 3'UTR, thus inhibiting the Foxl2-mediated transcriptional repression of StAR and CYP19A1to promote estradiol production.
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