Fig. 4: E proteins rearrangement on the original spherical particles to form catSP and clubSP.
From: High flavivirus structural plasticity demonstrated by a non-spherical morphological variant
a The Fab C10:ZIKV catSP structure shows when the E protein raft is locked by the Fabs as observed previously by the near-atomic resolution cryoEM structure of Fab C10:ZIKV spherical structure13, the rafts of the original spherical ZIKV particle (left) at elevated temperatures have to rotate relative to each other (curved arrows in left panel) to generate catSP helical structure (middle and right panels). Two rafts are shown in red and blue. b The Fab C10:DENV3 clubSP structure shows that Fab C10 does not lock the E dimers within the raft in DENV3, as the dimers have moved relative to each other. This suggests that, when incubating the spherical particles at elevated temperatures, structural rearrangement may include rotation of the rafts relative to each other (as observed in ZIKV catSP, curved arrow in left panel) and also the lateral motions (indicated by vertical arrows in left panel) of the E protein dimers, achieving the final helical structure (middle and right panels). These suggest that the inter-dimer interactions between the E proteins are also weak in addition to their inter-raft interactions. Two rafts each with three dimers are colored as different shades of red or blue and displayed as surface representations.
