Fig. 1: Organization of RSV structural proteins.

a Single z-slice from a representative cryo-tomogram of RSV virions (n = 27). Protein density is black. b A reoriented Z-projection (5 nm thick) from a tomogram of an RSV virion (n = 33 virions, n = 27 tomograms). In this orientation, the viral membrane and several structural proteins are localized within columns in the image as indicated by the colored bars in the bottom left. Red, Green, Cyan, Purple, and Pink correspond to the positions of RSV F, membrane, RSV M, RSV M2-1, and nucleocapsid respectively as indicated to the under panel c. c An average linear density profile across the left-side of the virion in (b) showing the peaks corresponding with each column of proteins or membrane. Colored boxes correspond to the legend and positions indicated in b. Source data are provided as a Source Data file. d Y-projection (9 nm thick) of X, Z slices of the virion in b, Z-position of slices in (e–g) are indicated by the red, cyan, and purple bars respectively (n = 33). e Single slice from the virion in (b) showing RSV F on the top of the virion in the X, Y plane (red bar in (d) indicates position of slice in Z direction). Select examples of pairs of density are highlighted by red boxes (n = 33). f Single slice from the M protein layer from the virion in b (cyan bar in d) (n = 33). g FFT of the M layer from the same filament and z-slice shown in (f) from a weighted-back projection tomogram (no denoising) (n = 33). h The frequency (nm⁻¹) of select peaks in the amplitude spectrum, determined by local maxima, is displayed in positions corresponding to the peaks in g. i Single slice from the virion in (b) showing the M2-1 layer (purple bar in d). Arrows point to ring like densities (n = 33). All slices from a binned by 4 tomogram (6.772 Å/px) denoised with cryoCARE. 500 nm scale bar for a, 50 nm scale bar for b, d, e, f, and i.