Fig. 5

IRES-dependent and cap-independent translation initiation. a CVB3 RNA employs an IRES to recruit the 40S subunit to start translation. The host protein DAP5, some eIFs and ITAFs are required for IRES-driven translational initiation. Subsequently, the translated 2A protein cleaves eIF4GI into two parts. The N-terminus of eIF4GI recruited to the IRES effectively promotes viral replication [87]. b SINV contains a 5′ cap structure. The DSH structure on its sgRNA can initiate non-AUG codon translation to enhance viral protein synthesis [88, 89]