title: Structural insights into ribosomal rescue by Dom34 and Hbs1 at near-atomic resolution.
abstract: The surveillance of mRNA translation is imperative for homeostasis. Monitoring the integrity of the message is essential, as the translation of aberrant mRNAs leads to stalling of the translational machinery. During ribosomal rescue, arrested ribosomes are specifically recognized by the conserved eukaryotic proteins Dom34 and Hbs1, to initiate their recycling. Here we solve the structure of Dom34 and Hbs1 bound to a yeast ribosome programmed with a nonstop mRNA at 3.3 Å resolution using cryo-electron microscopy. The structure shows that Domain N of Dom34 is inserted into the upstream mRNA-binding groove via direct stacking interactions with conserved nucleotides of 18S rRNA. It senses the absence of mRNA at the A-site and part of the mRNA entry channel by direct competition. Thus, our analysis establishes the structural foundation for the recognition of aberrantly stalled 80S ribosomes by the Dom34·Hbs1·GTP complex during Dom34-mediated mRNA surveillance pathways.
authors.affiliation: Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
authors.forename: Tarek
authors.initials: T
authors.lastname: Hilal
authors.affiliation: Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamamoto
authors.affiliation: Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
authors.forename: Justus
authors.initials: J
authors.lastname: Loerke
authors.affiliation: Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.|Max-Planck Institut für Molekulare Genetik, Ihnestrasse 63-73, 14195 Berlin, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Bürger
authors.affiliation: Max-Planck Institut für Molekulare Genetik, Ihnestrasse 63-73, 14195 Berlin, Germany.
authors.forename: Thorsten
authors.identifier: 0000-0001-9275-3146
authors.initials: T
authors.lastname: Mielke
authors.affiliation: Institut für Medizinische Physik und Biophysik, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
authors.forename: Christian M T
authors.initials: CM
authors.lastname: Spahn
mesh_terms: D018797:Cell Cycle Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D020285:Cryoelectron Microscopy; D004722:Endoribonucleases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006165:Guanylyl Imidodiphosphate / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D010445:Peptide Elongation Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000072417:Protein Domains; D054730:Protein Interaction Domains and Motifs; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D055672:Static Electricity
chemical_list: D018797:Cell Cycle Proteins; C077247:HBS1 protein, S cerevisiae; D018840:HSP70 Heat-Shock Proteins; D010445:Peptide Elongation Factors; D012331:RNA, Fungal; D012333:RNA, Messenger; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins; D006165:Guanylyl Imidodiphosphate; C112808:Dom34 protein, S cerevisiae; D004722:Endoribonucleases; D019204:GTP-Binding Proteins