Structural Insights into the Role of Eukaryotic Translation Initiation Factor 3 (eIF3) in Translation Mediated by the Hepatitis C Virus IRES

Cross-linking mass spectrometry was conducted to determine the positions of the non-core subunits (eIF3b, eIF3d, eIF3g, eIF3i, and eIF3j) of eIF3, that were not observed in cryo-EM densities, during elongation. For this analysis, the HCV IRES-initiated uORF2-stalled 80S ribosome was prepared from the in vitro translation system coupled with transcription, identical to the preparation used for the cryo-EM sample.