Fig. 2: Cryo-ET structures of VZV gB[H527P] resident on the membranes of EVs.

a and b A representative slice view of a tomogram (a; see Supplementary Table 1) and an EMAN2 cryo-EM map generated by subtomogram averaging (STA) (b) from EVs purified from BHK-21 cells transiently transfected with gB[H527P]. The white box in the upper panel of (a) highlights the area shown in the lower panel. Arrowheads point to gB[H527P] on the membrane of EVs. c A 10 Å resolution cryo-EM map derived from a local refinement of a tight mask and the associated Fourier Shell Correlation (FSC) curve. The coloring represents resolution from 9.8 Å (blue) to 12.4 Å (red). d STA maps and FSC curves for two classes (I – blue; II – red) of gB[H527P] identified on the surface of EVs using EMAN2. e STA maps of Class I and Class II gB[H527P] molecules (inset) with each panel showing MDFF of the homology model of the VZV gB²⁰ based on HSV-1 gB[H516P]³¹ into the cryo-EM maps. Snapshots from Supplementary Movie 1 are shown, the VZV gB domains are colored as for Fig. 1; DI (cyan), DII (green), DIII (yellow), DIV (orange), DV (red) and linker regions (hot pink). f Molecular models from the MDFF of the VZV gB homology model with boxed areas (i and ii) highlighting regions of structural differences between the two models. Arrows (blue to red gradient) represent the proposed movement between the class I and class II maps.