Figure 5.
Proposed mechanism of redox-controlled DNA site-recognition by AP-1 Fos/Jun. (A) an overview of the FosB (ribbon) structural transition is shown using JunD (tube) as a positional point of reference. The Cg-1 residue of FosB (shown as a yellow sphere) undergoes a ∼20 Å movement. FJoxi type I and FJ-DNA type I were used to construct the illustration. Arrows indicate the conformational rearrangement that FosB must undergo in order to bind DNA. Dashed line represents interatomic distances. (B–D) Kd0 attack, kink-helix transition and site-recognition as described in the text. (E) Simplified representation shows the redox switch of AP-1 controlling the coupled DNA-binding and structure transition. Color scheme is as indicated in Figure 3. Nucleic acid bases colored as T: brown, G: green, and C: cyan.