title: Partial methylation at Am100 in 18S rRNA of baker's yeast reveals ribosome heterogeneity on the level of eukaryotic rRNA modification.
abstract: Ribosome heterogeneity is of increasing biological significance and several examples have been described for multicellular and single cells organisms. In here we show for the first time a variation in ribose methylation within the 18S rRNA of Saccharomyces cerevisiae. Using RNA-cleaving DNAzymes, we could specifically demonstrate that a significant amount of S. cerevisiae ribosomes are not methylated at 2'-O-ribose of A100 residue in the 18S rRNA. Furthermore, using LC-UV-MS/MS of a respective 18S rRNA fragment, we could not only corroborate the partial methylation at A100, but could also quantify the methylated versus non-methylated A100 residue. Here, we exhibit that only 68% of A100 in the 18S rRNA of S.cerevisiae are methylated at 2'-O ribose sugar. Polysomes also contain a similar heterogeneity for methylated Am100, which shows that 40S ribosome subunits with and without Am100 participate in translation. Introduction of a multicopy plasmid containing the corresponding methylation guide snoRNA gene SNR51 led to an increased A100 methylation, suggesting the cellular snR51 level to limit the extent of this modification. Partial rRNA modification demonstrates a new level of ribosome heterogeneity in eukaryotic cells that might have substantial impact on regulation and fine-tuning of the translation process.
authors.affiliation: DECHEMA Research Institute, Biochemical Engineering, Frankfurt am Main, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Buchhaupt
authors.affiliation: Institute for Molecular Biosciences, Johann-Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Sunny
authors.initials: S
authors.lastname: Sharma
authors.affiliation: Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Mainz, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Kellner
authors.affiliation: Institute for Molecular Biosciences, Johann-Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Oswald
authors.affiliation: DECHEMA Research Institute, Biochemical Engineering, Frankfurt am Main, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Paetzold
authors.affiliation: Institute for Molecular Biosciences, Johann-Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Peifer
authors.affiliation: Institute for Molecular Biosciences, Johann-Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Watzinger
authors.affiliation: DECHEMA Research Institute, Biochemical Engineering, Frankfurt am Main, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Schrader
authors.affiliation: Institute of Pharmacy and Biochemistry, Johannes Gutenberg University, Mainz, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: Helm
authors.affiliation: Institute for Molecular Biosciences, Johann-Wolfgang Goethe University, Frankfurt am Main, Germany.
authors.forename: Karl-Dieter
authors.initials: KD
authors.lastname: Entian
mesh_terms: D008745:Methylation; D012335:RNA, Ribosomal / Q000235:genetics*; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D012335:RNA, Ribosomal