The hepatitis C virus (HCV) internal ribosome entry site (IRES) RNA drives internal initiation of viral protein synthesis during host cell infection. In the tertiary structure of the IRES RNA, two helical junctions create recognition sites for direct binding of the 40S ribosomal subunit and eukaryotic initiation factor 3 (eIF3). The 2.8 A resolution structure of the IIIabc four-way junction, which is critical for binding eIF3, reveals how junction nucleotides interact with an adjacent helix to position regions directly involved in eIF3 recognition. Two of the emergent helices stack to form a nearly continuous A-form duplex, while stacking of the other two helices is interrupted by the insertion of junction residues into the helix minor groove. This distorted stack probably serves as an important recognition surface for the translational machinery.
Crystal structure of an RNA tertiary domain essential to HCV IRES-mediated translation initiation.,Kieft JS, Zhou K, Grech A, Jubin R, Doudna JA Nat Struct Biol. 2002 May;9(5):370-4. PMID:11927953[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Kieft JS, Zhou K, Grech A, Jubin R, Doudna JA. Crystal structure of an RNA tertiary domain essential to HCV IRES-mediated translation initiation. Nat Struct Biol. 2002 May;9(5):370-4. PMID:11927953 doi:10.1038/nsb781
