title: Ki-67 is a PP1-interacting protein that organises the mitotic chromosome periphery.
abstract: When the nucleolus disassembles during open mitosis, many nucleolar proteins and RNAs associate with chromosomes, establishing a perichromosomal compartment coating the chromosome periphery. At present nothing is known about the function of this poorly characterised compartment. In this study, we report that the nucleolar protein Ki-67 is required for the assembly of the perichromosomal compartment in human cells. Ki-67 is a cell-cycle regulated protein phosphatase 1-binding protein that is involved in phospho-regulation of the nucleolar protein B23/nucleophosmin. Following siRNA depletion of Ki-67, NIFK, B23, nucleolin, and four novel chromosome periphery proteins all fail to associate with the periphery of human chromosomes. Correlative light and electron microscopy (CLEM) images suggest a near-complete loss of the entire perichromosomal compartment. Mitotic chromosome condensation and intrinsic structure appear normal in the absence of the perichromosomal compartment but significant differences in nucleolar reassembly and nuclear organisation are observed in post-mitotic cells.DOI: http://dx.doi.org/10.7554/eLife.01641.001.
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Booth
authors.affiliation: Cellular Dynamics Laboratory, Riken Advanced Science Institute, Wako Saitama, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Takagi
authors.affiliation: MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Luis
authors.initials: L
authors.lastname: Sanchez-Pulido
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Petfalski
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Giulia
authors.initials: G
authors.lastname: Vargiu
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Samejima
authors.affiliation: Cellular Dynamics Laboratory, Riken Advanced Science Institute, Wako Saitama, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Imamoto
authors.affiliation: MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom.
authors.forename: Chris P
authors.initials: CP
authors.lastname: Ponting
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Tollervey
authors.affiliation: Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom bill.earnshaw@ed.ac.uk.
authors.forename: William C
authors.initials: WC
authors.lastname: Earnshaw
authors.affiliation: Biosciences, Brunel University, London, United Kingdom Paola.Vagnarelli@brunel.ac.uk.
authors.forename: Paola
authors.initials: P
authors.lastname: Vagnarelli
mesh_terms: D002466:Cell Nucleolus / Q000378:metabolism* / Q000648:ultrastructure; D002877:Chromosomes, Human / Q000378:metabolism* / Q000648:ultrastructure; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D019394:Ki-67 Antigen / Q000235:genetics / Q000378:metabolism*; D008854:Microscopy, Electron; D008938:Mitosis; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D000090243:Nucleophosmin; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D054645:Protein Phosphatase 1 / Q000378:metabolism*; D034622:RNA Interference; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D020539:Sequence Analysis, Protein; D015398:Signal Transduction; D014162:Transfection; D000097796:Nucleolin
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D019394:Ki-67 Antigen; D009687:Nuclear Proteins; D000090243:Nucleophosmin; D010750:Phosphoproteins; D054645:Protein Phosphatase 1; D016601:RNA-Binding Proteins; D000097796:Nucleolin; C492406:NIFK protein, human; C000716967:NPM1 protein, human
keywords: chromosomes; mitosis; nucleolus; phosphatases