Structural basis for the binding of IRES RNAs to the head of the ribosomal 40S subunit

Nucleic Acids Res. 2011 Jul;39(12):5264-75. doi: 10.1093/nar/gkr114. Epub 2011 Mar 4.


Some viruses exploit internal initiation for their propagation in the host cell. This type of initiation is facilitated by structured elements (internal ribosome entry site, IRES) upstream of the initiator AUG and requires only a reduced number of canonical initiation factors. An important example are IRES of the virus family Dicistroviridae that bind to the inter-subunit side of the small ribosomal 40S subunit and lead to the formation of elongation-competent 80S ribosomes without the help of any initiation factor. Here, we present a comprehensive functional and structural analysis of eukaryotic-specific ribosomal protein rpS25 in the context of this type of initiation and propose a structural model explaining the essential involvement of rpS25 for hijacking the ribosome.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 5' Untranslated Regions*
  • Base Sequence
  • Dicistroviridae / genetics*
  • Models, Molecular
  • Molecular Sequence Data
  • Peptide Chain Initiation, Translational
  • RNA, Viral / chemistry*
  • Ribosomal Proteins / chemistry*
  • Ribosomal Proteins / metabolism
  • Ribosome Subunits, Small, Eukaryotic / chemistry*
  • Saccharomyces cerevisiae / genetics
  • Saccharomyces cerevisiae Proteins / chemistry*
  • Saccharomyces cerevisiae Proteins / metabolism


  • 5' Untranslated Regions
  • RNA, Viral
  • RPS21A protein, S cerevisiae
  • Ribosomal Proteins
  • Saccharomyces cerevisiae Proteins