The comparison of mammalian eIF4G1 and eIF4G2. (A) The schematic structures of mammalian eIF4G1 and eIF4G2. Both eIF4G homologs possess three HEAT domains: MIF4G, MA3, and W2. The resolved structural domains are designated inside the boxes, and binding sites for the initiation factors and MNK1/2 are shown under the diagrams. The arrows denote cleavage sites for the picornaviral proteases and for caspase-3 (casp-3). The M-FAG (eIF4G1493–1136) and p86 fragment (eIF4G21–792) are produced by caspase-3. The picornaviral 2A protease (2A pro) separates a p100 fragment from eIF4G1, while eIF4G2 is cleaved by the picornaviral 3C protease (3C pro). (B) The comparison of eIF4G1 and eIF4G2 domains. The amino acid sequences of corresponding domains were pairwise aligned using the EMBL-EBI needle (EMBOSS) service with standard Needleman–Wunsch algorithm preset settings. The calculated percentages of identical and similar amino acids are indicated. The linker domain refers to the amino acid sequence between the MIF4G and MA3 domains.
