Fig. 4: Difference electron density reflecting early stages of AUC–TUC1 transition.
From: Synchronous RNA conformational changes trigger ordered phase transitions in crystals

Fo − Fo difference electron density maps, displayed for apo1 (a) and apo2 (b), generated using the ligand-free model (PDB: 5E54) and the observed structure factor differences between data sets. Left: AUC-10 s—AUC free; right: AUC-25 s–AUC-10 s. Positive and negative density are shown in green and red, respectively, contoured at 3 sigma.