Novel Mechanisms of Progesterone Antagonists and Progesterone Receptor

  title={Novel Mechanisms of Progesterone Antagonists and Progesterone Receptor},
  author={Dean P. Edwards and Susan A. Leonhardt and Elizabeth K. Gass-Handel},
  journal={Journal of the Society for Gynecologic Investigation},
  pages={S22 - S24}
The progesterone receptor (PR), as a member of the nuclear receptor superfamily of ligand-dependent transcription factors, activates gene transcription through binding to specific palindromic progesterone response elements (PRE) in the promoter region of progestin-responsive genes. The progesterone antagonists ZK98299 (Onapristone) and RU 486 (Mifepristone) inhibit the transcriptional activity of PR by complex mechanisms at concentrations much lower than the progestins. Altered conformation is… 

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