这个基因编码类固醇受体超家族的一个成员。编码蛋白介导孕酮的生理效应，孕酮在与妊娠的建立和维持有关的生殖事件中起着核心作用。这个基因使用第一外显子中两个不同的启动子和翻译起始位点来产生几个转录变体，包括蛋白质编码和非蛋白质编码。两种亚型（A和B）是相同的，除了在B亚型的N端发现的另外165个氨基酸外，它们在很少重叠的情况下调节自己的反应基因和生理效应。
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.