Transcriptional regulator. Critical factor essential for ovary differentiation and maintenance, and repression of the genetic program for somatic testis determination. Prevents trans-differentiation of ovary to testis through transcriptional repression of the Sertoli cell-promoting gene SOX9. Has apoptotic activity in ovarian cells. Suppresses ESR1-mediated transcription of PTGS2/COX2 stimulated by tamoxifen. Activates SIRT1 transcription under cellular stress conditions. Activates transcription of OSR2. Is a regulator of CYP19 expression. Is a transcriptional repressor of STAR. Participates in SMAD3-dependent transcription of FST via the intronic SMAD-binding element. Interacts with ESR1. Interacts with UBE2I/UBC9 (By similarity). Interacts with SMAD3. Interacts with DDX20. Expressed in the mesenchyme of developing eyelids. Expressed in ovaries throughout development and adulthood, localized to the undifferentiated granulosa cells in small and medium follicles as well as cumulus cells of preovulatory follicles. Expressed in the pituitary. Sumoylated with SUMO1; sumoylation is required for transcriptional repression activity.