Extended Data Fig. 5. Single-particle cryo-EM analysis of monomeric and dimeric cRNA-bound human H3N2 FluPol_A heterotrimer in complex with Nb8205.

a, Representative micrograph of cRNA-bound FluPol_A in complex with Nb8205 embedded in vitreous ice. b, Representative 2D class averages. c, FSC curves for the 3D reconstruction using gold-standard refinement in RELION, indicating overall map resolution of 3.79 Å and 4.15 Å for the monomeric and dimeric FluPol_A form, respectively, and the model-to-map FSC. Curves are shown for phase randomisation, unmasked, masked and phase-randomisation-corrected masked maps. d, f, 3D reconstruction locally filtered and coloured according to RELION local resolution for the dimeric (d) and monomeric (f) form. e, g, Angular distribution of particle projections for the dimeric (e) and monomeric (g) form with the cryo-EM map shown in grey. h, Dimer of FluPol_A heterotrimers bound to cRNA promoter and Nb8205 rigid body fitted into the cryo-EM map of dimeric cRNA-bound FluPol_A heterotrimer in complex with Nb8205. i, Cryo-EM map of the dimeric cRNA-bound FluPol_A heterotrimer in complex with Nb8205 revealing an extra density (green) located next to the 3ʹ end of the 5ʹ cRNA, as observed for the cRNA-bound FluPol_A dimer (Extended Data Fig. 3g, h).