Figure 6. Conformational changes within the receptor between the agonist- and antagonist bound complexes.
(A) Overall view and extracellular zoom into the binding pocket of the superimposed models CRF (magenta)-CRF1R (grey) and dFXCRF(12-41) (orange)-CRF1R (light blue) highlighting the inward shift of helices VI and VII in the antagonist-bound model. (B) Schematic presentation of the active CRF (magenta)-CRF1R complex and the inactive dFXCRF(12-41) (orange)-CRF1R complex showing the predicted conformational changes between the ‘wide’ agonist-bound and the ‘compact’ antagonist-bound states of the receptor. Apo CRF1R is expected to have a more flexible conformation of the TMD and sample a range of conformations.