title: Dom34 rescues ribosomes in 3' untranslated regions.
abstract: Ribosomes that stall before completing peptide synthesis must be recycled and returned to the cytoplasmic pool. The protein Dom34 and cofactors Hbs1 and Rli1 can dissociate stalled ribosomes in vitro, but the identity of targets in the cell is unknown. Here, we extend ribosome profiling methodology to reveal a high-resolution molecular characterization of Dom34 function in vivo. Dom34 removes stalled ribosomes from truncated mRNAs, but, in contrast, does not generally dissociate ribosomes on coding sequences known to trigger stalling, such as polyproline. We also show that Dom34 targets arrested ribosomes near the ends of 3' UTRs. These ribosomes appear to gain access to the 3' UTR via a mechanism that does not require decoding of the mRNA. These results suggest that ribosomes frequently enter downstream noncoding regions and that Dom34 carries out the important task of rescuing them.
authors.affiliation: Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
authors.forename: Nicholas R
authors.initials: NR
authors.lastname: Guydosh
authors.affiliation: Howard Hughes Medical Institute, Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA. Electronic address: ragreen@jhmi.edu.
authors.forename: Rachel
authors.initials: R
authors.lastname: Green
mesh_terms: D020413:3' Untranslated Regions; D018797:Cell Cycle Proteins / Q000378:metabolism*; D003958:Diamide / Q000494:pharmacology; D004722:Endoribonucleases / Q000378:metabolism*; D023282:Nuclease Protection Assays; D014176:Protein Biosynthesis; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D020413:3' Untranslated Regions; D018797:Cell Cycle Proteins; D029701:Saccharomyces cerevisiae Proteins; D003958:Diamide; C112808:Dom34 protein, S cerevisiae; D004722:Endoribonucleases