Extended Data Figure 1: Comparison of HCV and CSFV IRES-bound ribosomal complexes.
From: Hepatitis-C-virus-like internal ribosome entry sites displace eIF3 to gain access to the 40S subunit
a, Secondary structures of (left) the HCV IRES and (right) the CSFV IRES. Domain II of each IRES is indicated by a red dashed oval; elements of the pseudoknot and subdomains IIIa–IIIe are colour-coded as in Extended Data Fig. 6. b, Cryo-electron microscopy reconstructions of the HCV IRES bound to the rabbit 40S subunit at 20 Å resolution8 (left), the HCV IRES bound to the 40S subunit of cycloheximide-stalled human 80S ribosomes at 15 Å resolution23 (middle) (accession code EMD-1138) and the CSFV ΔII-IRES bound to the rabbit 40S subunits at 8.5 Å resolution (right) (this study). In all panels, the IRES-40S subunit is viewed from the solvent side; the 40S subunit is displayed in yellow and the IRES in cyan. The red dashed circles in left and middle panels show a discontinuity in the density of domain II in the HCV IRES bound to the 40S subunit compared to the HCV IRES bound to 80S ribosomes. The dashed circle in the right hand panel highlights CSFV IRES subdomain IIId2, which has no counterpart in the HCV IRES.
