Figure 4. SLIV interactions with S5 and S28. (A) Contacts between ribosomal protein S5p (S7) (purple) β-hairpin and mRNA at the exit site⁶¹ (PDB ID: 2WDM). (B) Interactions between mRNA and 40S ribosomal proteins S5 (purple) and S28 (cyan) highlighted in the crystal structure of Oryctolagus ribosome⁶³ (PDB ID: 4KZZ). (C) Comparison of human ribosomal S28 model (cyan) with 30S ribosomal protein S12 (PDB ID: 3OHY, purple).⁶⁴The interface residues observed in 30S protein S12 are also highlighted. (D) The docked model of domain II-S5-S25 complex relative to S28 and domain IV model. (E) S5 protein was UV cross -linked with α- ³²P UTP labeled HCV IRES in the absence (Lane 2) or presence of 50 fold and 100 fold molar excess of unlabeled HCV IRES (18–383), SLIV (domain IV), SLIII (domain III) and SLII (domain II) in vitro transcribed RNAs (Lanes 3–10). NP indicates no protein control (Lane 1).