(A) Generic primary structure schematic. Functional domains are as indicated: DBD, DNA binding domain; HBD, hormone binding domain. An activation function is located within both the N-terminal region and the HBD (AF-1 and AF-2, respectively) (B) HRE2 promoter assembly model. Macromolecular species and interactions are as indicated: circles, hormone-bound receptor monomers; squares, receptor dimers. Dimerization (kdim) is coupled to response element binding (kint); complete occupancy is coupled to an inter-site cooperative interaction (kc). Arrow refers to the direction of transcriptional start site. (C) Chimeric GR/ER; N-terminal region and DBD of GR is fused to the HBD of ER-α. Amino acid number is indicated above each receptor. Functional regions are as indicated for Panel A.