title: Reduced expression of the mouse ribosomal protein Rpl17 alters the diversity of mature ribosomes by enhancing production of shortened 5.8S rRNA.
abstract: Processing of rRNA during ribosome assembly can proceed through alternative pathways but it is unclear whether this could affect the structure of the ribosome. Here, we demonstrate that shortage of a ribosomal protein can change pre-rRNA processing in a way that over time alters ribosome diversity in the cell. Reducing the amount of Rpl17 in mouse cells led to stalled 60S subunit maturation, causing degradation of most of the synthesized precursors. A fraction of pre-60S subunits, however, were able to complete maturation, but with a 5'-truncated 5.8S rRNA, which we named 5.8SC. The 5' exoribonuclease Xrn2 is involved in the generation of both 5.8S(C) and the canonical long form of 5.8S rRNA. Ribosomes containing 5.8S(C) rRNA are present in various mouse and human cells and engage in translation. These findings uncover a previously undescribed form of mammalian 5.8S rRNA and demonstrate that perturbations in ribosome assembly can be a source of heterogeneity in mature ribosomes.
authors.affiliation: Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, New Jersey 08084, USA.
authors.forename: Minshi
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, New Jersey 08084, USA.
authors.forename: Andrey V
authors.initials: AV
authors.lastname: Parshin
authors.affiliation: Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, New Jersey 08084, USA.
authors.forename: Natalia
authors.initials: N
authors.lastname: Shcherbik
authors.affiliation: Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, New Jersey 08084, USA.
authors.forename: Dimitri G
authors.initials: DG
authors.lastname: Pestov
mesh_terms: D000818:Animals; D005095:Exoribonucleases / Q000235:genetics; D055785:Gene Knockdown Techniques; D051379:Mice; D012322:RNA Precursors / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D012340:RNA, Ribosomal, 5.8S / Q000096:biosynthesis*; D012269:Ribosomal Proteins / Q000378:metabolism*; D012270:Ribosomes / Q000378:metabolism*
chemical_list: D012322:RNA Precursors; D012340:RNA, Ribosomal, 5.8S; D012269:Ribosomal Proteins; C032493:ribosomal protein L17; D005095:Exoribonucleases; C092452:Xrn2 protein, mouse
keywords: RNA processing; mammalian cells; ribosomal protein; ribosome; ribosome biogenesis