Fig. 5. Structural analysis of extracellular virions.

a–c Slices of tomograms showing extracellular virions released from A549-ACE2, VeroE6, and Calu3 cells, respectively. d–f magnified views of (a–c), for better visualization, 10 slices were averaged. Exemplarily, S glycoproteins in a pre-fusion (arrow) or post-fusion conformation (arrowhead) are marked, vRNP complexes are encircled with dashed lines. g Plot profile through the viral envelope (VE, magenta) of virions released from VeroE6 cells and adjacent plasma membrane (PM, green) to determine monolayer separation (n = 129 and 49, respectively, SD indicated). h Number of vRNP complexes per virion (n = 28) released from VeroE6 cells. Data are represented as a histogram with a bin size of 3 and Gaussian fit (R² = 0.8645). i, j Subtomogram average of vRNP complexes from 1570 individual vRNPs found in 15 tomograms. Central XZ-slice (i) and XY-slice (j) are shown. k, l Isosurface representation of the subtomogram average (Movie S5) shown from the top (k) and side view (l). Scale bars: a–c 100 nm; d–f 50 nm; i–l 5 nm.