A Triticum mosaic virus cis-regulatory element controls cap-independent translation, likely by directing ribosome targeting through base pairing with 18S rRNA.
Identifies a broad-spectrum mechanism regulating translation initiation for both plant- and animal-hosted picornaviruses involving a YX-AUG motif.
Uncapped viral RNAs often rely on their 5′ leader sequences to initiate translation, and the Triticum mosaic virus (TriMV) devotes an astonishing 7% of its genome to directing ribosomes to the correct AUG. Here we uncover a novel mechanism by which a TriMV cis -regulatory element controls cap-independent translation. The upstream region of the functional AUG contains a 16-nt polypyrimidine tract located 11 nt from the initiation site. Based on functional redundancy with similar motifs derived from human picornaviruses, the motif is likely to operate by directing ribosome targeting through base pairing with 18S rRNA. Our results provide the first report of a broad-spectrum mechanism regulating translation initiation for both plant- and animal-hosted picornaviruses.
Jaramillo-Mesa et al. (Fri,) conducted a other in Triticum mosaic virus translation. A Triticum mosaic virus cis-regulatory element controls cap-independent translation, likely by directing ribosome targeting through base pairing with 18S rRNA.