{"type":"root","children":[{"type":"paragraph","children":[{"type":"text","value":"The progesterone receptor (PR) also known as NR3C3 (nuclear receptor subfamily 3, group C, member 3), is an intracellular steroid receptor that specifically binds progesterone. PR is encoded by a single gene PGR residing on chromosome 11q22; it has two main forms, A and B, which differ in their molecular weight. Like all steroid receptors, the progesterone receptor has an amino and a carboxyl terminal, and between them the regulatory domain, a DNA binding domain, the hinge section, and the hormone binding domain."}]}]}