這個基因編碼類固醇受體超家族的一個成員。編碼蛋白介導孕酮的生理效應，孕酮在與妊娠的建立和維持有關的生殖事件中起著核心作用。這個基因使用第一外顯子中兩個不同的啟動子和翻譯起始位點來產生幾個轉錄變體，包括蛋白質編碼和非蛋白質編碼。兩種亞型（A和B）是相同的，除了在B亞型的N端發現的另外165個氨基酸外，它們在很少重疊的情況下調節自己的反應基因和生理效應。
This gene encodes a member of the steroid receptor superfamily. The encoded protein mediates the physiological effects of progesterone, which plays a central role in reproductive events associated with the establishment and maintenance of pregnancy. This gene uses two distinct promotors and translation start sites in the first exon to produce several transcript variants, both protein coding and non-protein coding. Two of the isoforms (A and B) are identical except for an additional 165 amino acids found in the N-terminus of isoform B and mediate their own response genes and physiologic effects with little overlap.