. These results suggest that eIF3 binds to the solvent side of the 40S subunit in a way that provides access to the interface side for the two eIF3 segments (NIP1-NTD and TIF32-CTD) that interact with eIF1, eIF5, and the eIF2/GTP/Met-tRNA i Met ternary complex.[Keywords: Eukaryotic translation initiation factor (eIF); multifactor complex (MFC); translational control; protein synthesis; 40S ribosome binding; TIF32/NIP1] Supplemental material is available at http://www.genesdev.org.