The eukaryotic translation initiation factor 4B (eIF4B) plays a critical role in recruiting the 40S ribosomal subunit to the mRNA.It functions in close association with eIF4F and eIF4A. It binds near the 5'-terminal cap of mRNA in the presence of eIF4F and ATP. It promotes the ATPase activity and the ATP-dependent RNA unwinding activity of both eIF4A and eIF4FSynonyms: Eukaryotic translation initiation factor 4B, eIF-4B