The largest of the mammalian translation initiation factors, eIF3, consists of at least eight subunits ranging in mass from 35 to 170 kDa. eIF3 binds to the 40 S ribosome in an early step of translation initiation and promotes the binding of methionyl-tRNAi and mRNA [1].

1: Conservation and diversity of eukaryotic translation initiation factor eIF3. Asano K, Kinzy TG, Merrick WC, Hershey JW; J Biol Chem 1997;272:1101-1109. PMID:8995409

2: Direct eIF2-eIF3 contact in the multifactor complex is important for translation initiation in vivo. Valasek L, Nielsen KH, Hinnebusch AG; EMBO J 2002;21:5886-5898. PMID:12411506