title: Specialized yeast ribosomes: a customized tool for selective mRNA translation.
abstract: Evidence is now accumulating that sub-populations of ribosomes - so-called specialized ribosomes - can favour the translation of subsets of mRNAs. Here we use a large collection of diploid yeast strains, each deficient in one or other copy of the set of ribosomal protein (RP) genes, to generate eukaryotic cells carrying distinct populations of altered 'specialized' ribosomes. We show by comparative protein synthesis assays that different heterologous mRNA reporters based on luciferase are preferentially translated by distinct populations of specialized ribosomes. These mRNAs include reporters carrying premature termination codons (PTC) thus allowing us to identify specialized ribosomes that alter the efficiency of translation termination leading to enhanced synthesis of the wild-type protein. This finding suggests that these strains can be used to identify novel therapeutic targets in the ribosome. To explore this further we examined the translation of the mRNA encoding the extracellular matrix protein laminin β3 (LAMB3) since a LAMB3-PTC mutant is implicated in the blistering skin disease Epidermolysis bullosa (EB). This screen identified specialized ribosomes with reduced levels of RP L35B as showing enhanced synthesis of full-length LAMB3 in cells expressing the LAMB3-PTC mutant. Importantly, the RP L35B sub-population of specialized ribosomes leave both translation of a reporter luciferase carrying a different PTC and bulk mRNA translation largely unaltered.
authors.affiliation: Department of Cell Biology, University of Salzburg, Salzburg, Austria.
authors.forename: Johann W
authors.initials: JW
authors.lastname: Bauer
authors.forename: Clemens
authors.initials: C
authors.lastname: Brandl
authors.forename: Olaf
authors.initials: O
authors.lastname: Haubenreisser
authors.forename: Bjoern
authors.initials: B
authors.lastname: Wimmer
authors.forename: Manuela
authors.initials: M
authors.lastname: Weber
authors.forename: Thomas
authors.initials: T
authors.lastname: Karl
authors.forename: Alfred
authors.initials: A
authors.lastname: Klausegger
authors.forename: Michael
authors.initials: M
authors.lastname: Breitenbach
authors.forename: Helmut
authors.initials: H
authors.lastname: Hintner
authors.forename: Tobias
authors.initials: T
authors.lastname: von der Haar
authors.forename: Mick F
authors.initials: MF
authors.lastname: Tuite
authors.forename: Lore
authors.initials: L
authors.lastname: Breitenbach-Koller
mesh_terms: D017930:Genes, Reporter; D008156:Luciferases / Q000378:metabolism; D008958:Models, Molecular; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012269:Ribosomal Proteins / Q000378:metabolism; D054683:Ribosome Subunits, Large, Eukaryotic / Q000378:metabolism; D054682:Ribosome Subunits, Small, Eukaryotic / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D014170:Transformation, Genetic
chemical_list: D012333:RNA, Messenger; D012269:Ribosomal Proteins; D008156:Luciferases