title: Rrp5p, Noc1p and Noc2p form a protein module which is part of early large ribosomal subunit precursors in S. cerevisiae.
abstract: Eukaryotic ribosome biogenesis requires more than 150 auxiliary proteins, which transiently interact with pre-ribosomal particles. Previous studies suggest that several of these biogenesis factors function together as modules. Using a heterologous expression system, we show that the large ribosomal subunit (LSU) biogenesis factor Noc1p of Saccharomyces cerevisiae can simultaneously interact with the LSU biogenesis factor Noc2p and Rrp5p, a factor required for biogenesis of the large and the small ribosomal subunit. Proteome analysis of RNA polymerase-I-associated chromatin and chromatin immunopurification experiments indicated that all members of this protein module and a specific set of LSU biogenesis factors are co-transcriptionally recruited to nascent ribosomal RNA (rRNA) precursors in yeast cells. Further ex vivo analyses showed that all module members predominantly interact with early pre-LSU particles after the initial pre-rRNA processing events have occurred. In yeast strains depleted of Noc1p, Noc2p or Rrp5p, levels of the major LSU pre-rRNAs decreased and the respective other module members were associated with accumulating aberrant rRNA fragments. Therefore, we conclude that the module exhibits several binding interfaces with pre-ribosomes. Taken together, our results suggest a co- and post-transcriptional role of the yeast Rrp5p-Noc1p-Noc2p module in the structural organization of early LSU precursors protecting them from non-productive RNase activity.
authors.affiliation: Universität Regensburg, Biochemie-Zentrum Regensburg (BZR), Lehrstuhl Biochemie III, 93053 Regensburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hierlmeier
authors.forename: Juliane
authors.initials: J
authors.lastname: Merl
authors.forename: Martina
authors.initials: M
authors.lastname: Sauert
authors.forename: Jorge
authors.initials: J
authors.lastname: Perez-Fernandez
authors.forename: Patrick
authors.initials: P
authors.lastname: Schultz
authors.forename: Astrid
authors.initials: A
authors.lastname: Bruckmann
authors.forename: Stephan
authors.initials: S
authors.lastname: Hamperl
authors.forename: Uli
authors.initials: U
authors.lastname: Ohmayer
authors.forename: Reinhard
authors.initials: R
authors.lastname: Rachel
authors.forename: Anja
authors.initials: A
authors.lastname: Jacob
authors.forename: Kristin
authors.initials: K
authors.lastname: Hergert
authors.forename: Rainer
authors.initials: R
authors.lastname: Deutzmann
authors.forename: Joachim
authors.initials: J
authors.lastname: Griesenbeck
authors.forename: Ed
authors.initials: E
authors.lastname: Hurt
authors.forename: Philipp
authors.initials: P
authors.lastname: Milkereit
authors.forename: Jochen
authors.initials: J
authors.lastname: Baßler
authors.forename: Herbert
authors.initials: H
authors.lastname: Tschochner
mesh_terms: D000818:Animals; D001665:Binding Sites; D002352:Carrier Proteins / Q000378:metabolism*; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism*; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D054683:Ribosome Subunits, Large, Eukaryotic / Q000378:metabolism*; D054682:Ribosome Subunits, Small, Eukaryotic / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D002352:Carrier Proteins; D004268:DNA-Binding Proteins; C115485:MAK21 protein, S cerevisiae; C429647:NOC2 protein, S cerevisiae; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; C102025:RRP5 protein, S cerevisiae; D011994:Recombinant Proteins; D029701:Saccharomyces cerevisiae Proteins