The eukaryotic initiation factor-4A (eIF4A) family consists of 3 closely related proteins EIF4A1, EIF4A2, and EIF4A3. These factors are required for the binding of mRNA to 40S ribosomal subunits. Eukaryotic initiation factor (eIF) complex 2 forms a ternary complex with GTP and the initiator Met-tRNA – this process is regulated by guanine nucleotide exchange and phosphorylation and serves as the main regulatory element of the bottleneck of protein expression.