SNAP output for PDB entry 5a2q [SNAP web server]

PDB-id

5a2q; SNAP-derived features in text and JSON formats; DNAproDB

Class

ribosome

Method

cryo-EM (3.9 Å)

Summary

Structure of the hcv ires bound to the human ribosome

Reference

Quade N, Boehringer D, Leibundgut M, Van Den Heuvel J, Ban N (2015): "Cryo-Em Structure of Hepatitis C Virus Ires Bound to the Human Ribosome at 3.9 Angstrom Resolution." Nat.Commun., 6, 7646. doi: 10.1038/NCOMMS8646.

Abstract

Hepatitis C virus (HCV), a widespread human pathogen, is dependent on a highly structured 5'-untranslated region of its mRNA, referred to as internal ribosome entry site (IRES), for the translation of all of its proteins. The HCV IRES initiates translation by directly binding to the small ribosomal subunit (40S), circumventing the need for many eukaryotic translation initiation factors required for mRNA scanning. Here we present the cryo-EM structure of the human 40S ribosomal subunit in complex with the HCV IRES at 3.9 Å resolution, determined by focused refinement of an 80S ribosome-HCV IRES complex. The structure reveals the molecular details of the interactions between the IRES and the 40S, showing that expansion segment 7 (ES7) of the 18S rRNA acts as a central anchor point for the HCV IRES. The structural data rationalizes previous biochemical and genetic evidence regarding the initiation mechanism of the HCV and other related IRESs.