Figure 1.

(A) Architecture of full-length NRs. VDR has an extended helix in the hinge domain that positions the LBD, and may limit inter-domain flexibility. (B) A model for regulation of the LBD by DNA binding. Changes in the positioning of the hinge could modulate the LBD dimer interface, and in turn change the conformation of helix 12, which forms part of the coactivator binding site. (C) For the steroid receptors AR, GR, MR and PR, interaction with DNA (or other proteins) could stabilize different low affinity dimer interfaces in the LBD.