title: Spindle-independent condensation-mediated segregation of yeast ribosomal DNA in late anaphase.
abstract: Mitotic cell division involves the equal segregation of all chromosomes during anaphase. The presence of ribosomal DNA (rDNA) repeats on the right arm of chromosome XII makes it the longest in the budding yeast genome. Previously, we identified a stage during yeast anaphase when rDNA is stretched across the mother and daughter cells. Here, we show that resolution of sister rDNAs is achieved by unzipping of the locus from its centromere-proximal to centromere-distal regions. We then demonstrate that during this stretched stage sister rDNA arrays are neither compacted nor segregated despite being largely resolved from each other. Surprisingly, we find that rDNA segregation after this period no longer requires spindles but instead involves Cdc14-dependent rDNA axial compaction. These results demonstrate that chromosome resolution is not simply a consequence of compacting chromosome arms and that overall rDNA compaction is necessary to mediate the segregation of the long arm of chromosome XII.
authors.affiliation: Cell Cycle Group, Clinical Sciences Centre, Medical Research Council, Imperial College London, London W12 0NN, England, UK.
authors.forename: Félix
authors.initials: F
authors.lastname: Machín
authors.forename: Jordi
authors.initials: J
authors.lastname: Torres-Rosell
authors.forename: Adam
authors.initials: A
authors.lastname: Jarmuz
authors.forename: Luis
authors.initials: L
authors.lastname: Aragón
mesh_terms: D000705:Anaphase / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002453:Cell Cycle / Q000187:drug effects; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D020090:Chromosome Segregation / Q000502:physiology*; D004275:DNA, Ribosomal / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007700:Kinetics; D008164:Luminescent Proteins / Q000235:genetics; D000072235:Mating Factor; D008677:Metaphase / Q000502:physiology; D008856:Microscopy, Fluorescence; D009154:Mutation; D015739:Nocodazole / Q000494:pharmacology; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D010455:Peptides / Q000494:pharmacology; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D008941:Spindle Apparatus / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D013194:Staining and Labeling
chemical_list: D001426:Bacterial Proteins; C074860:CDC14 protein, S cerevisiae; D002352:Carrier Proteins; D018797:Cell Cycle Proteins; D004275:DNA, Ribosomal; D004268:DNA-Binding Proteins; C105579:FOB1 protein, S cerevisiae; D008164:Luminescent Proteins; C119300:Net1 protein, S cerevisiae; D009687:Nuclear Proteins; D010455:Peptides; D029701:Saccharomyces cerevisiae Proteins; C083139:Tet O resistance protein, Bacteria; C054562:yellow fluorescent protein, Bacteria; D049452:Green Fluorescent Proteins; D000072235:Mating Factor; D017027:Protein Tyrosine Phosphatases; D015739:Nocodazole