title: RNA interference is essential for cellular quiescence.
abstract: Quiescent cells play a predominant role in most organisms. Here we identify RNA interference (RNAi) as a major requirement for quiescence (G0phase of the cell cycle) in Schizosaccharomyces pombe RNAi mutants lose viability at G0entry and are unable to maintain long-term quiescence. We identified suppressors of G0defects in cells lacking Dicer (dcr1Δ), which mapped to genes involved in chromosome segregation, RNA polymerase-associated factors, and heterochromatin formation. We propose a model in which RNAi promotes the release of RNA polymerase in cycling and quiescent cells: (i) RNA polymerase II release mediates heterochromatin formation at centromeres, allowing proper chromosome segregation during mitotic growth and G0entry, and (ii) RNA polymerase I release prevents heterochromatin formation at ribosomal DNA during quiescence maintenance. Our model may account for the codependency of RNAi and histone H3 lysine 9 methylation throughout eukaryotic evolution.
authors.affiliation: Howard Hughes Medical Institute-Gordon and Betty Moore Foundation, Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
authors.forename: B
authors.initials: B
authors.lastname: Roche
authors.affiliation: Dynamics of the Genome Unit, Department of Genomes and Genetics, Institut Pasteur, UMR3525, 25-28 rue du Docteur Roux, Paris 75015, France.
authors.forename: B
authors.initials: B
authors.lastname: Arcangioli
authors.affiliation: Howard Hughes Medical Institute-Gordon and Betty Moore Foundation, Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA. martiens@cshl.edu.
authors.forename: R A
authors.initials: RA
authors.lastname: Martienssen
mesh_terms: D002503:Centromere / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D020090:Chromosome Segregation / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics / Q000378:metabolism; D006570:Heterochromatin / Q000378:metabolism; D009154:Mutation; D034622:RNA Interference; D012318:RNA Polymerase I / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism; D016192:Resting Phase, Cell Cycle / Q000235:genetics*; D043244:Ribonuclease III / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics* / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004275:DNA, Ribosomal; D006570:Heterochromatin; C489651:Rik1 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; D012319:RNA Polymerase II; D012318:RNA Polymerase I; D043244:Ribonuclease III