Human phospho-Progesterone R/NR3C3 (S294) Antibody

Progesterone Receptor B (PR-B) is a 118 kDa member of the NR3 subfamily within the nuclear hormone receptor family of proteins. It is expressed in female reproductive tissues as well as neurons throughout the CNS. PR-B is particularly important in the mammary gland where it mediates proliferative responses to progesterone. Human PR‑B is 933 amino acids (aa) in length. It contains an N-terminal regulatory region (aa 1‑566), a DNA binding domain (aa 567‑639), and a steroid‑binding region (aa 681‑933). Ligand binding induces a key phosphorylation event at Ser294 catalyzed by ERK1/2, regulating cell growth, cell adhesion, and gene transcription. An alternate start site at Met165 generates 90 kDa PR-A, an isoform particularly important in the ovary and uterus that insures fertility.