Download MendeleytRNA-mRNA mimicry drives translation initiation from a viral IRES.
Costantino, D.A., Pfingsten, J.S., Rambo, R.P., Kieft, J.S.(2008) Nat Struct Mol Biol 15: 57-64
- PubMed: 18157151
- DOI: https://doi.org/10.1038/nsmb1351
- Primary Citation of Related Structures:
3B31 - PubMed Abstract:
Internal ribosome entry site (IRES) RNAs initiate protein synthesis in eukaryotic cells by a noncanonical cap-independent mechanism. IRESes are critical for many pathogenic viruses, but efforts to understand their function are complicated by the diversity of IRES sequences as well as by limited high-resolution structural information. The intergenic region (IGR) IRESes of the Dicistroviridae viruses are powerful model systems to begin to understand IRES function. Here we present the crystal structure of a Dicistroviridae IGR IRES domain that interacts with the ribosome's decoding groove. We find that this RNA domain precisely mimics the transfer RNA anticodon-messenger RNA codon interaction, and its modeled orientation on the ribosome helps explain translocation without peptide bond formation. When combined with a previous structure, this work completes the first high-resolution description of an IRES RNA and provides insight into how RNAs can manipulate complex biological machines.
Organizational Affiliation:
Department of Biochemistry and Molecular Genetics, University of Colorado at Denver and Health Sciences Center, Mail Stop 8101, PO Box 6511, Aurora, Colorado 80045, USA.
