1
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Parashara P, Medina-Pritchard B, Abad MA, Sotelo-Parrilla P, Thamkachy R, Grundei D, Zou J, Spanos C, Kumar CN, Basquin C, Das V, Yan Z, Al-Murtadha AA, Kelly DA, McHugh T, Imhof A, Rappsilber J, Jeyaprakash AA. PLK1-mediated phosphorylation cascade activates Mis18 complex to ensure centromere inheritance. Science 2024; 385:1098-1104. [PMID: 39236175 DOI: 10.1126/science.ado8270] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 07/30/2024] [Indexed: 09/07/2024]
Abstract
Accurate chromosome segregation requires the attachment of microtubules to centromeres, epigenetically defined by the enrichment of CENP-A nucleosomes. During DNA replication, CENP-A nucleosomes undergo dilution. To preserve centromere identity, correct amounts of CENP-A must be restored in a cell cycle-controlled manner orchestrated by the Mis18 complex (Mis18α-Mis18β-Mis18BP1). We demonstrate here that PLK1 interacts with the Mis18 complex by recognizing self-primed phosphorylations of Mis18α (Ser54) and Mis18BP1 (Thr78 and Ser93) through its Polo-box domain. Disrupting these phosphorylations perturbed both centromere recruitment of the CENP-A chaperone HJURP and new CENP-A loading. Biochemical and functional analyses showed that phosphorylation of Mis18α and PLK1 binding were required to activate Mis18α-Mis18β and promote Mis18 complex-HJURP interaction. Thus, our study reveals key molecular events underpinning the licensing role of PLK1 in ensuring accurate centromere inheritance.
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Affiliation(s)
- Pragya Parashara
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | | | - Maria Alba Abad
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | | | - Reshma Thamkachy
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - David Grundei
- Gene Center Munich, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Juan Zou
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Christos Spanos
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Chandni Natalia Kumar
- Protein Analysis Unit, Biomedical Centre Munich, Faculty of Medicine, Ludwig-Maximilians-University, 82152 Munich, Germany
| | - Claire Basquin
- Department of Structural Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Vimal Das
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Zhaoyue Yan
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | | | - David A Kelly
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Toni McHugh
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Axel Imhof
- Department of Structural Biology, Max Planck Institute of Biochemistry, D-82152 Martinsried, Germany
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
- Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany
| | - A Arockia Jeyaprakash
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
- Gene Center Munich, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
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2
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Conti D, Verza AE, Pesenti ME, Cmentowski V, Vetter IR, Pan D, Musacchio A. Role of protein kinase PLK1 in the epigenetic maintenance of centromeres. Science 2024; 385:1091-1097. [PMID: 39236163 DOI: 10.1126/science.ado5178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 07/30/2024] [Indexed: 09/07/2024]
Abstract
The centromere, a chromosome locus defined by the histone H3-like protein centromeric protein A (CENP-A), promotes assembly of the kinetochore to bind microtubules during cell division. Centromere maintenance requires CENP-A to be actively replenished by dedicated protein machinery in the early G1 phase of the cell cycle to compensate for its dilution after DNA replication. Cyclin-dependent kinases (CDKs) limit CENP-A deposition to once per cell cycle and function as negative regulators outside of early G1. Antithetically, Polo-like kinase 1 (PLK1) promotes CENP-A deposition in early G1, but the molecular details of this process are still unknown. We reveal here a phosphorylation network that recruits PLK1 to the deposition machinery to control a conformational switch required for licensing the CENP-A deposition reaction. Our findings clarify how PLK1 contributes to the epigenetic maintenance of centromeres.
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Affiliation(s)
- Duccio Conti
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Arianna Esposito Verza
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
- Centre for Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, 45141 Essen, Germany
| | - Marion E Pesenti
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Verena Cmentowski
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
- Centre for Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, 45141 Essen, Germany
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Dongqing Pan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
- Centre for Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, 45141 Essen, Germany
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3
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Thamkachy R, Medina-Pritchard B, Park SH, Chiodi CG, Zou J, de la Torre-Barranco M, Shimanaka K, Abad MA, Gallego Páramo C, Feederle R, Ruksenaite E, Heun P, Davies OR, Rappsilber J, Schneidman-Duhovny D, Cho US, Jeyaprakash AA. Structural basis for Mis18 complex assembly and its implications for centromere maintenance. EMBO Rep 2024; 25:3348-3372. [PMID: 38951710 PMCID: PMC11315898 DOI: 10.1038/s44319-024-00183-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Revised: 05/06/2024] [Accepted: 06/06/2024] [Indexed: 07/03/2024] Open
Abstract
The centromere, defined by the enrichment of CENP-A (a Histone H3 variant) containing nucleosomes, is a specialised chromosomal locus that acts as a microtubule attachment site. To preserve centromere identity, CENP-A levels must be maintained through active CENP-A loading during the cell cycle. A central player mediating this process is the Mis18 complex (Mis18α, Mis18β and Mis18BP1), which recruits the CENP-A-specific chaperone HJURP to centromeres for CENP-A deposition. Here, using a multi-pronged approach, we characterise the structure of the Mis18 complex and show that multiple hetero- and homo-oligomeric interfaces facilitate the hetero-octameric Mis18 complex assembly composed of 4 Mis18α, 2 Mis18β and 2 Mis18BP1. Evaluation of structure-guided/separation-of-function mutants reveals structural determinants essential for cell cycle controlled Mis18 complex assembly and centromere maintenance. Our results provide new mechanistic insights on centromere maintenance, highlighting that while Mis18α can associate with centromeres and deposit CENP-A independently of Mis18β, the latter is indispensable for the optimal level of CENP-A loading required for preserving the centromere identity.
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Affiliation(s)
- Reshma Thamkachy
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | | | - Sang Ho Park
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Carla G Chiodi
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Juan Zou
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | | | - Kazuma Shimanaka
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Maria Alba Abad
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | | | - Regina Feederle
- Monoclonal Antibody Core Facility, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), 85764, Neuherberg, Germany
| | - Emilija Ruksenaite
- Institute Novo Nordisk Foundation Centre for Protein Research, Copenhagen, Denmark
| | - Patrick Heun
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Owen R Davies
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK
- Institute of Biotechnology, Technische Universität Berlin, 13355, Berlin, Germany
| | - Dina Schneidman-Duhovny
- School of Computer Science and Engineering, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Uhn-Soo Cho
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - A Arockia Jeyaprakash
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, EH9 3BF, UK.
- Gene Center, Department of Biochemistry, Ludwig Maximilians Universität, Munich, Germany.
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4
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Salinas-Luypaert C, Fachinetti D. Canonical and noncanonical regulators of centromere assembly and maintenance. Curr Opin Cell Biol 2024; 89:102396. [PMID: 38981198 DOI: 10.1016/j.ceb.2024.102396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/10/2024] [Accepted: 06/15/2024] [Indexed: 07/11/2024]
Abstract
Centromeres are specialized chromosomal domains where the kinetochores assemble during cell division to ensure accurate transmission of the genetic information to the two daughter cells. The centromeric function is evolutionary conserved and, in most organisms, centromeres are epigenetically defined by a unique chromatin containing the histone H3 variant CENP-A. The canonical regulators of CENP-A assembly and maintenance are well-known, yet some of the molecular mechanisms regulating this complex process have only recently been unveiled. We review the most recent advances on the topic, including the emergence of new and unexpected factors that favor and regulate CENP-A assembly and/or maintenance.
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Affiliation(s)
- Catalina Salinas-Luypaert
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR 144 & UMR3664, 26 rue d'Ulm, 75005, Paris, France.
| | - Daniele Fachinetti
- Institut Curie, PSL Research University, Sorbonne Université, CNRS, UMR 144 & UMR3664, 26 rue d'Ulm, 75005, Paris, France.
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5
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Balachandra V, Shrestha RL, Hammond CM, Lin S, Hendriks IA, Sethi SC, Chen L, Sevilla S, Caplen NJ, Chari R, Karpova TS, McKinnon K, Todd MA, Koparde V, Cheng KCC, Nielsen ML, Groth A, Basrai MA. DNAJC9 prevents CENP-A mislocalization and chromosomal instability by maintaining the fidelity of histone supply chains. EMBO J 2024; 43:2166-2197. [PMID: 38600242 PMCID: PMC11148058 DOI: 10.1038/s44318-024-00093-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/12/2024] Open
Abstract
The centromeric histone H3 variant CENP-A is overexpressed in many cancers. The mislocalization of CENP-A to noncentromeric regions contributes to chromosomal instability (CIN), a hallmark of cancer. However, pathways that promote or prevent CENP-A mislocalization remain poorly defined. Here, we performed a genome-wide RNAi screen for regulators of CENP-A localization which identified DNAJC9, a J-domain protein implicated in histone H3-H4 protein folding, as a factor restricting CENP-A mislocalization. Cells lacking DNAJC9 exhibit mislocalization of CENP-A throughout the genome, and CIN phenotypes. Global interactome analysis showed that DNAJC9 depletion promotes the interaction of CENP-A with the DNA-replication-associated histone chaperone MCM2. CENP-A mislocalization upon DNAJC9 depletion was dependent on MCM2, defining MCM2 as a driver of CENP-A deposition at ectopic sites when H3-H4 supply chains are disrupted. Cells depleted for histone H3.3, also exhibit CENP-A mislocalization. In summary, we have defined novel factors that prevent mislocalization of CENP-A, and demonstrated that the integrity of H3-H4 supply chains regulated by histone chaperones such as DNAJC9 restrict CENP-A mislocalization and CIN.
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Grants
- 75N91019D00024 NCI NIH HHS
- HHSN261201500003I NCI NIH HHS
- ZIA BC 010822 HHS | NIH | NCI | Center for Cancer Research (CCR)
- ZIA BC 011704 HHS | NIH | NCI | Center for Cancer Research (CCR)
- 75N91019D00024 NCI NIH HHS
- HHSN261201500003I NCI NIH HHS
- 0135-00096B and 8020-00220B,EPIC-XS-823839,R146-A9159-16-S2 Independent Research Fund Denmark, European Union's Horizon 2020 research and innovation program, Danish Cancer Society
- ERC CoG 724436,R198-2015-269 and R313-2019-448,7016-00042B,NNF21OC0067425,NNF14CC0001 European Research Council, Lund-beck Foundation, Independent Research Fund Denmark, Novo Nordisk Foundation
- HHS | NIH | National Cancer Institute (NCI)
- Independent Research Fund Denmark, European Union’s Horizon 2020 research and innovation program, Danish Cancer Society
- NIH Intramural Research Program, Intramural Research Program of the National Center for Advancing Translational Sciences (NCATS)
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Affiliation(s)
- Vinutha Balachandra
- Yeast Genome Stability Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Roshan L Shrestha
- Yeast Genome Stability Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Colin M Hammond
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK.
| | - Shinjen Lin
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Ivo A Hendriks
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Subhash Chandra Sethi
- Yeast Genome Stability Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Lu Chen
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Samantha Sevilla
- Collaborative Bioinformatics Resource, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Natasha J Caplen
- Functional Genetics Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Raj Chari
- Genome Modification Core (GMC), Frederick National Lab for Cancer Research, Frederick, MD, USA
| | - Tatiana S Karpova
- Optical Microscopy Core, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Katherine McKinnon
- Flow Cytometry Core, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Matthew Am Todd
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Vishal Koparde
- Collaborative Bioinformatics Resource, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Advanced Biomedical Computational Science, Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Ken Chih-Chien Cheng
- Functional Genomics Laboratory, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA
| | - Michael L Nielsen
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anja Groth
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Munira A Basrai
- Yeast Genome Stability Section, Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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6
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London N, Medina-Pritchard B, Spanos C, Rappsilber J, Jeyaprakash AA, Allshire RC. Direct recruitment of Mis18 to interphase spindle pole bodies promotes CENP-A chromatin assembly. Curr Biol 2023; 33:4187-4201.e6. [PMID: 37714149 DOI: 10.1016/j.cub.2023.08.063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 08/04/2023] [Accepted: 08/22/2023] [Indexed: 09/17/2023]
Abstract
CENP-A chromatin specifies mammalian centromere identity, and its chaperone HJURP replenishes CENP-A when recruited by the Mis18 complex (Mis18C) via M18BP1/KNL2 to CENP-C at kinetochores during interphase. However, the Mis18C recruitment mechanism remains unresolved in species lacking M18BP1, such as fission yeast. Fission yeast centromeres cluster at G2 spindle pole bodies (SPBs) when CENP-ACnp1 is replenished and where Mis18C also localizes. We show that SPBs play an unexpected role in concentrating Mis18C near centromeres through the recruitment of Mis18 by direct binding to the major SPB linker of nucleoskeleton and cytoskeleton (LINC) component Sad1. Mis18C recruitment by Sad1 is important for CENP-ACnp1 chromatin establishment and acts in parallel with a CENP-C-mediated Mis18C recruitment pathway to maintain centromeric CENP-ACnp1 but operates independently of Sad1-mediated centromere clustering. SPBs therefore provide a non-chromosomal scaffold for both Mis18C recruitment and centromere clustering during G2. This centromere-independent Mis18-SPB recruitment provides a mechanism that governs de novo CENP-ACnp1 chromatin assembly by the proximity of appropriate sequences to SPBs and highlights how nuclear spatial organization influences centromere identity.
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Affiliation(s)
- Nitobe London
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Bethan Medina-Pritchard
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Christos Spanos
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Juri Rappsilber
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK; Institute of Biotechnology, Technische Universität, 13355 Berlin, Germany
| | - A Arockia Jeyaprakash
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK; Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Robin C Allshire
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK.
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7
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Das A, Boese KG, Tachibana K, Baek SH, Lampson MA, Black BE. Centromere-specifying nucleosomes persist in aging mouse oocytes in the absence of nascent assembly. Curr Biol 2023; 33:3759-3765.e3. [PMID: 37582374 PMCID: PMC10528140 DOI: 10.1016/j.cub.2023.07.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 07/17/2023] [Accepted: 07/19/2023] [Indexed: 08/17/2023]
Abstract
Centromeres direct genetic inheritance but are not themselves genetically encoded. Instead, centromeres are defined epigenetically by the presence of a histone H3 variant, CENP-A.1 In cultured somatic cells, an established paradigm of cell-cycle-coupled propagation maintains centromere identity: CENP-A is partitioned between sisters during replication and replenished by new assembly, which is restricted to G1. The mammalian female germ line challenges this model because of the cell-cycle arrest between pre-meiotic S phase and the subsequent G1, which can last for the entire reproductive lifespan (months to decades). New CENP-A chromatin assembly maintains centromeres during prophase I in worm and starfish oocytes,2,3 suggesting that a similar process may be required for centromere inheritance in mammals. To test this hypothesis, we developed an oocyte-specific conditional knockout (cKO) mouse for Mis18α, an essential component of the assembly machinery. We find that embryos derived from Mis18α knockout oocytes fail to assemble CENP-A nucleosomes prior to zygotic genome activation (ZGA), validating the knockout model. We show that deletion of Mis18α in the female germ line at the time of birth has no impact on centromeric CENP-A nucleosome abundance, even after 6-8 months of aging. In addition, there is no detectable detriment to fertility. Thus, centromere chromatin is maintained long-term, independent of new assembly during the extended prophase I arrest in mouse oocytes.
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Affiliation(s)
- Arunika Das
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katelyn G Boese
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kikue Tachibana
- Department of Totipotency, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Sung Hee Baek
- Creative Research Initiatives Center for Epigenetic Code and Diseases, Seoul National University, Seoul 08826, Republic of Korea
| | - Michael A Lampson
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn Center for Genome Integrity, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Ben E Black
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA; Penn Center for Genome Integrity, University of Pennsylvania, Philadelphia, PA 19104, USA.
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8
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Flores Servin JC, Brown RR, Straight AF. Repression of CENP-A assembly in metaphase requires HJURP phosphorylation and inhibition by M18BP1. J Cell Biol 2023; 222:e202110124. [PMID: 37141119 PMCID: PMC10165474 DOI: 10.1083/jcb.202110124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 01/06/2023] [Accepted: 03/01/2023] [Indexed: 05/05/2023] Open
Abstract
Centromeres are the foundation for mitotic kinetochore assembly and thus are essential for chromosome segregation. Centromeres are epigenetically defined by nucleosomes containing the histone H3 variant CENP-A. CENP-A nucleosome assembly is uncoupled from replication and occurs in G1, but how cells control this timing is incompletely understood. The formation of CENP-A nucleosomes in vertebrates requires CENP-C and the Mis18 complex which recruit the CENP-A chaperone HJURP to centromeres. Using a cell-free system for centromere assembly in X. laevis egg extracts, we discover two activities that inhibit CENP-A assembly in metaphase. HJURP phosphorylation prevents the interaction between HJURP and CENP-C in metaphase, blocking the delivery of soluble CENP-A to centromeres. Non-phosphorylatable mutants of HJURP constitutively bind CENP-C in metaphase but are not sufficient for new CENP-A assembly. We find that the M18BP1.S subunit of the Mis18 complex also binds to CENP-C to competitively inhibit HJURP's access to centromeres. Removal of these two inhibitory activities causes CENP-A assembly in metaphase.
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Affiliation(s)
| | - Rachel R. Brown
- Department of Biochemistry, School of Medicine, Stanford University, Stanford, CA, USA
| | - Aaron F. Straight
- Department of Biochemistry, School of Medicine, Stanford University, Stanford, CA, USA
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9
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Das A, Boese KG, Tachibana K, Baek SH, Lampson MA, Black BE. Centromere-specifying nucleosomes persist in aging mouse oocytes in the absence of nascent assembly. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.18.541332. [PMID: 37292821 PMCID: PMC10245701 DOI: 10.1101/2023.05.18.541332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Centromeres direct genetic inheritance but are not themselves genetically encoded. Instead, centromeres are defined epigenetically by the presence of a histone H3 variant, CENP-A 1 . In cultured somatic cells, an established paradigm of cell cycle-coupled propagation maintains centromere identity: CENP-A is partitioned between sisters during replication and replenished by new assembly, which is restricted to G1. The mammalian female germline challenges this model because of the cell cycle arrest between pre-meiotic S-phase and the subsequent G1, which can last for the entire reproductive lifespan (months to decades). New CENP-A chromatin assembly maintains centromeres during prophase I in worm and starfish oocyte 2,3 , suggesting that a similar process may be required for centromere inheritance in mammals. However, we show that centromere chromatin is maintained long-term independent of new assembly during the extended prophase I arrest in mouse oocytes. Conditional knockout of Mis18α, an essential component of the assembly machinery, in the female germline at the time of birth has almost no impact on centromeric CENP-A nucleosome abundance nor any detectable detriment to fertility.
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Affiliation(s)
- Arunika Das
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Katelyn G. Boese
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kikue Tachibana
- Department of Totipotency, Max Planck Institute of Biochemistry, Martinsried 82152, Germany
| | - Sung Hee Baek
- Creative Research Initiatives Center for Epigenetic Code and Diseases, Seoul National University, Seoul 08826
| | - Michael A. Lampson
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Penn Center for Genome Integrity, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ben E. Black
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Epigenetics Institute; University of Pennsylvania, Philadelphia PA 19104, USA
- Penn Center for Genome Integrity, University of Pennsylvania, Philadelphia, PA 19104, USA
- Lead Contact
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10
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Trier I, Black EM, Joo YK, Kabeche L. ATR protects centromere identity by promoting DAXX association with PML nuclear bodies. Cell Rep 2023; 42:112495. [PMID: 37163376 DOI: 10.1016/j.celrep.2023.112495] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 03/10/2023] [Accepted: 04/25/2023] [Indexed: 05/12/2023] Open
Abstract
Centromere protein A (CENP-A) defines centromere identity and nucleates kinetochore formation for mitotic chromosome segregation. Here, we show that ataxia telangiectasia and Rad3-related (ATR) kinase, a master regulator of the DNA damage response, protects CENP-A occupancy at interphase centromeres in a DNA damage-independent manner. In unperturbed cells, ATR localizes to promyelocytic leukemia nuclear bodies (PML NBs), which house the histone H3.3 chaperone DAXX (death domain-associated protein 6). We find that ATR inhibition reduces DAXX association with PML NBs, resulting in the DAXX-dependent loss of CENP-A and an aberrant increase in H3.3 at interphase centromeres. Additionally, we show that ATR-dependent phosphorylation within the C terminus of DAXX regulates CENP-A occupancy at centromeres and DAXX localization. Lastly, we demonstrate that acute ATR inhibition during interphase leads to kinetochore formation defects and an increased rate of lagging chromosomes. These findings highlight a mechanism by which ATR protects centromere identity and genome stability.
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Affiliation(s)
- Isabelle Trier
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Elizabeth M Black
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Yoon Ki Joo
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA
| | - Lilian Kabeche
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA; Yale Cancer Biology Institute, Yale University, West Haven, CT 06516, USA.
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11
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van den Berg SJW, East S, Mitra S, Jansen LET. p97/VCP drives turnover of SUMOylated centromeric CCAN proteins and CENP-A. Mol Biol Cell 2023; 34:br6. [PMID: 36989032 PMCID: PMC10162411 DOI: 10.1091/mbc.e23-01-0035] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023] Open
Abstract
The centromere is a unique chromatin domain that links sister chromatids and forms the attachment site for spindle microtubules in mitosis. Centromere inheritance is largely DNA sequence-independent but strongly reliant on a self-propagating chromatin domain featuring nucleosomes containing the H3 variant CENP-A. Unlike other histones, CENP-A is maintained with unusually high stability in chromatin. Previously, we have shown that mitotic maintenance of CENP-A and other constitutive centromere-associated network (CCAN) proteins is controlled by a dynamic SUMO cycle and that the deSUMOylase SENP6 is necessary for stable maintenance of CENP-A at the centromere. Here, we discover that the removal of SENP6 leads to a rapid loss of the CCAN, followed by a delayed loss of centromeric CENP-A, indicating that the CCAN is the primary SUMO target. We found that the ATP-dependent segregase p97/VCP removes centromeric CENP-A in a SUMO-dependent manner and interacts physically with the CCAN and CENP-A chromatin. Our data suggest a direct role of p97 in removing centromeric CENP-A via SUMOylated CCAN proteins, thereby ensuring centromere homeostasis and potentially preventing ectopic CENP-A accumulation.
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Affiliation(s)
- Sebastiaan J. W. van den Berg
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
- Instituto Gulbenkian de Ciencia, 2780-156 Oeiras, Portugal
| | - Samuel East
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Sreyoshi Mitra
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
| | - Lars E. T. Jansen
- Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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12
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Jiang H, Ariyoshi M, Hori T, Watanabe R, Makino F, Namba K, Fukagawa T. The cryo-EM structure of the CENP-A nucleosome in complex with ggKNL2. EMBO J 2023; 42:e111965. [PMID: 36744604 PMCID: PMC10015371 DOI: 10.15252/embj.2022111965] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 02/07/2023] Open
Abstract
Centromere protein A (CENP-A) nucleosomes containing the centromere-specific histone H3 variant CENP-A represent an epigenetic mark that specifies centromere position. The Mis18 complex is a licensing factor for new CENP-A deposition via the CENP-A chaperone, Holliday junction recognition protein (HJURP), on the centromere chromatin. Chicken KINETOCHORE NULL2 (KNL2) (ggKNL2), a Mis18 complex component, has a CENP-C-like motif, and our previous study suggested that ggKNL2 directly binds to the CENP-A nucleosome to recruit HJURP/CENP-A to the centromere. However, the molecular basis for CENP-A nucleosome recognition by ggKNL2 has remained unclear. Here, we present the cryo-EM structure of the chicken CENP-A nucleosome in complex with a ggKNL2 fragment containing the CENP-C-like motif. Chicken KNL2 distinguishes between CENP-A and histone H3 in the nucleosome using the CENP-C-like motif and its downstream region. Both the C-terminal tail and the RG-loop of CENP-A are simultaneously recognized as CENP-A characteristics. The CENP-A nucleosome-ggKNL2 interaction is thus essential for KNL2 functions. Furthermore, our structural, biochemical, and cell biology data indicate that ggKNL2 changes its binding partner at the centromere during chicken cell cycle progression.
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Affiliation(s)
- Honghui Jiang
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Mariko Ariyoshi
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Tetsuya Hori
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Reito Watanabe
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Fumiaki Makino
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
- JEOL Ltd.AkishimaJapan
| | - Keiichi Namba
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
- RIKEN Center for Biosystems Dynamics Research and SPring‐8 CenterSuitaJapan
- JEOL YOKOGUSHI Research Alliance LaboratoriesOsaka UniversitySuitaJapan
| | - Tatsuo Fukagawa
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
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13
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Mahlke MA, Lumerman L, Ly P, Nechemia-Arbely Y. Epigenetic centromere identity is precisely maintained through DNA replication but is uniquely specified among human cells. Life Sci Alliance 2023; 6:e202201807. [PMID: 36596606 PMCID: PMC9811134 DOI: 10.26508/lsa.202201807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 01/05/2023] Open
Abstract
Centromere identity is defined and maintained epigenetically by the presence of the histone variant CENP-A. How centromeric CENP-A position is specified and precisely maintained through DNA replication is not fully understood. The recently released Telomere-to-Telomere (T2T) genome assembly containing the first complete human centromere sequences provides a new resource for examining CENP-A position. Mapping CENP-A position in clones of the same cell line to the T2T assembly identified highly similar CENP-A position after multiple cell divisions. In contrast, centromeric CENP-A epialleles were evident at several centromeres of different human cell lines, demonstrating the location of CENP-A enrichment and the site of kinetochore recruitment vary among human cells. Across the cell cycle, CENP-A molecules deposited in G1 phase are maintained in their precise position through DNA replication. Thus, despite CENP-A dilution during DNA replication, CENP-A is precisely reloaded onto the same sequences within the daughter centromeres, maintaining unique centromere identity among human cells.
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Affiliation(s)
- Megan A Mahlke
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Lior Lumerman
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peter Ly
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Yael Nechemia-Arbely
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
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14
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Liu X, Zhao X, Yang J, Wang H, Piao Y, Wang L. High expression of AP2M1 correlates with worse prognosis by regulating immune microenvironment and drug resistance to R-CHOP in diffuse large B cell lymphoma. Eur J Haematol 2023; 110:198-208. [PMID: 36335584 DOI: 10.1111/ejh.13895] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/02/2022] [Accepted: 11/03/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND First-line treatment with R-CHOP has cured 50%-60% patients of diffuse large B cell lymphoma (DLBCL), and more than one-third patients will eventually progressed to relapsed/refractory disease with dismal outcomes. Adaptor Related Protein Complex 2 Subunit Mu 1 (AP2M1) is required for the activity of a vacuolar ATPase and may also play an important role in regulating the intracellular trafficking and function of CTLA-4 protein. Herein, using both public databases and our own tumor samples, we aimed to demonstrate the prognostic role of AP2M1 and the potential tumor-promoting mechanisms in DLBCL. METHOD Using public datasets of DLBCL from both GEO and TCGA databases, we analyzed the role of AP2M1 in mediating chemoresistance to R-CHOP and its correlation with various clinical parameters and prognosis. By using various R packages, we evaluated the role of AP2M1 on regulating tumor immune microenvironment. Moreover, tumor samples of DLBCL from Beijing TongRen Hospital were used to validate our findings by immunohistochemistry staining. RESULT Expression of AP2M1 was significantly increased in DLBCL, which was correlated with poor prognosis and a variety of clinical indicators. On the basis of enrichment analysis, it was found that AP2M1 may be related to intracellular receptor signaling pathway. Through immune analysis and drug prediction, we found that the expression of AP2M1 affected the immune environment and drug response of DLBCL, which further revealed the important role of AP2M1 in DLBCL. By analyzing 61 patients treated uniformly with R-CHOP regimen in our center, we validated the above findings that high expression of AP2M1 correlated with inferior survival outcomes and affected sensitivity to R-CHOP treatment. CONCLUSION Expression of AP2M1 may affect the prognosis of DLBCL patients probably by affecting the immune environment and the responses to many drugs in treating DLBCL, indicating AP2M1 as a potential therapy target in DLBCL.
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Affiliation(s)
- Xindi Liu
- Department of Hematology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Xiaoli Zhao
- Department of Pathology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Head and Neck Molecular Diagnostic Pathology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Jing Yang
- Department of Hematology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Henan Wang
- Department of Hematology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Yingshi Piao
- Department of Pathology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Head and Neck Molecular Diagnostic Pathology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
| | - Liang Wang
- Department of Hematology, Beijing TongRen Hospital, Capital Medical University, Beijing, China
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15
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Dong Q, Li F. Cell cycle control of kinetochore assembly. Nucleus 2022; 13:208-220. [PMID: 36037227 PMCID: PMC9427032 DOI: 10.1080/19491034.2022.2115246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
The kinetochore is a large proteinaceous structure assembled on the centromeres of chromosomes. The complex machinery links chromosomes to the mitotic spindle and is essential for accurate chromosome segregation during cell division. The kinetochore is composed of two submodules: the inner and outer kinetochore. The inner kinetochore is assembled on centromeric chromatin and persists with centromeres throughout the cell cycle. The outer kinetochore attaches microtubules to the inner kinetochore, and assembles only during mitosis. The review focuses on recent advances in our understanding of the mechanisms governing the proper assembly of the outer kinetochore during mitosis and highlights open questions for future investigation.
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Affiliation(s)
- Qianhua Dong
- Department of Biology, New York University, New York, NY, USA
| | - Fei Li
- Department of Biology, New York University, New York, NY, USA
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16
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Wang Y, Wu L, Yuen KWY. The roles of transcription, chromatin organisation and chromosomal processes in holocentromere establishment and maintenance. Semin Cell Dev Biol 2022; 127:79-89. [PMID: 35042676 DOI: 10.1016/j.semcdb.2022.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 01/09/2022] [Accepted: 01/09/2022] [Indexed: 12/15/2022]
Abstract
The centromere is a unique functional region on each eukaryotic chromosome where the kinetochore assembles and orchestrates microtubule attachment and chromosome segregation. Unlike monocentromeres that occupy a specific region on the chromosome, holocentromeres are diffused along the length of the chromosome. Despite being less common, holocentromeres have been verified in almost 800 nematode, insect, and plant species. Understanding of the molecular and epigenetic regulation of holocentromeres is lagging that of monocentromeres. Here we review how permissive locations for holocentromeres are determined across the genome, potentially by chromatin organisation, transcription, and non-coding RNAs, specifically in the nematode C. elegans. In addition, we discuss how holocentric CENP-A or CENP-T-containing nucleosomes are recruited and deposited, through the help of histone chaperones, licensing factors, and condensin complexes, both during de novo holocentromere establishment, and in each mitotic cell cycle. The process of resolving sister centromeres after DNA replication in holocentric organisms is also mentioned. Conservation and diversity between holocentric and monocentric organisms are highlighted, and outstanding questions are proposed.
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Affiliation(s)
- Yue Wang
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong
| | - Lillian Wu
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong; Epigenetics and Genome Stability Team, The Institute of Cancer Research, 237 Fulham Road, London SW3 6JB, United Kingdom
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong.
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17
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Sundararajan K, Straight AF. Centromere Identity and the Regulation of Chromosome Segregation. Front Cell Dev Biol 2022; 10:914249. [PMID: 35721504 PMCID: PMC9203049 DOI: 10.3389/fcell.2022.914249] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 05/13/2022] [Indexed: 11/13/2022] Open
Abstract
Eukaryotes segregate their chromosomes during mitosis and meiosis by attaching chromosomes to the microtubules of the spindle so that they can be distributed into daughter cells. The complexity of centromeres ranges from the point centromeres of yeast that attach to a single microtubule to the more complex regional centromeres found in many metazoans or holocentric centromeres of some nematodes, arthropods and plants, that bind to dozens of microtubules per kinetochore. In vertebrates, the centromere is defined by a centromere specific histone variant termed Centromere Protein A (CENP-A) that replaces histone H3 in a subset of centromeric nucleosomes. These CENP-A nucleosomes are distributed on long stretches of highly repetitive DNA and interspersed with histone H3 containing nucleosomes. The mechanisms by which cells control the number and position of CENP-A nucleosomes is unknown but likely important for the organization of centromeric chromatin in mitosis so that the kinetochore is properly oriented for microtubule capture. CENP-A chromatin is epigenetically determined thus cells must correct errors in CENP-A organization to prevent centromere dysfunction and chromosome loss. Recent improvements in sequencing complex centromeres have paved the way for defining the organization of CENP-A nucleosomes in centromeres. Here we discuss the importance and challenges in understanding CENP-A organization and highlight new discoveries and advances enabled by recent improvements in the human genome assembly.
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18
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Renaud-Pageot C, Quivy JP, Lochhead M, Almouzni G. CENP-A Regulation and Cancer. Front Cell Dev Biol 2022; 10:907120. [PMID: 35721491 PMCID: PMC9201071 DOI: 10.3389/fcell.2022.907120] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
In mammals, CENP-A, a histone H3 variant found in the centromeric chromatin, is critical for faithful chromosome segregation and genome integrity maintenance through cell divisions. Specifically, it has dual functions, enabling to define epigenetically the centromere position and providing the foundation for building up the kinetochore. Regulation of its dynamics of synthesis and deposition ensures to propagate proper centromeres on each chromosome across mitosis and meiosis. However, CENP-A overexpression is a feature identified in many cancers. Importantly, high levels of CENP-A lead to its mislocalization outside the centromere. Recent studies in mammals have begun to uncover how CENP-A overexpression can affect genome integrity, reprogram cell fate and impact 3D nuclear organization in cancer. Here, we summarize the mechanisms that orchestrate CENP-A regulation. Then we review how, beyond its centromeric function, CENP-A overexpression is linked to cancer state in mammalian cells, with a focus on the perturbations that ensue at the level of chromatin organization. Finally, we review the clinical interest for CENP-A in cancer treatment.
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19
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The ins and outs of CENP-A: Chromatin dynamics of the centromere-specific histone. Semin Cell Dev Biol 2022; 135:24-34. [PMID: 35422390 DOI: 10.1016/j.semcdb.2022.04.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 04/05/2022] [Accepted: 04/05/2022] [Indexed: 01/08/2023]
Abstract
Centromeres are highly specialised chromosome domains defined by the presence of an epigenetic mark, the specific histone H3 variant called CENP-A (centromere protein A). They constitute the genomic regions on which kinetochores form and when defective cause segregation defects that can lead to aneuploidy and cancer. Here, we discuss how CENP-A is established and maintained to propagate centromere identity while subjected to dynamic chromatin remodelling during essential cellular processes like DNA repair, replication, and transcription. We highlight parallels and identify conserved mechanisms between different model organism with a particular focus on 1) the establishment of CENP-A at centromeres, 2) CENP-A maintenance during transcription and replication, and 3) the mechanisms that help preventing CENP-A localization at non-centromeric sites. We then give examples of how timely loading of new CENP-A to the centromere, maintenance of old CENP-A during S-phase and transcription, and removal of CENP-A at non-centromeric sites are coordinated and controlled by an intricate network of factors whose identity is slowly being unravelled.
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20
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Jeffery D, Lochhead M, Almouzni G. CENP-A: A Histone H3 Variant with Key Roles in Centromere Architecture in Healthy and Diseased States. Results Probl Cell Differ 2022; 70:221-261. [PMID: 36348109 DOI: 10.1007/978-3-031-06573-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Centromeres are key architectural components of chromosomes. Here, we examine their construction, maintenance, and functionality. Focusing on the mammalian centromere- specific histone H3 variant, CENP-A, we highlight its coevolution with both centromeric DNA and its chaperone, HJURP. We then consider CENP-A de novo deposition and the importance of centromeric DNA recently uncovered with the added value from new ultra-long-read sequencing. We next review how to ensure the maintenance of CENP-A at the centromere throughout the cell cycle. Finally, we discuss the impact of disrupting CENP-A regulation on cancer and cell fate.
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Affiliation(s)
- Daniel Jeffery
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France
| | - Marina Lochhead
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France
| | - Geneviève Almouzni
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France.
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21
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Wenda JM, Prosée RF, Gabus C, Steiner FA. Mitotic chromosome condensation requires phosphorylation of the centromeric protein KNL-2 in C. elegans. J Cell Sci 2021; 134:272713. [PMID: 34734636 PMCID: PMC8714079 DOI: 10.1242/jcs.259088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022] Open
Abstract
Centromeres are chromosomal regions that serve as sites for kinetochore formation and microtubule attachment, processes that are essential for chromosome segregation during mitosis. Centromeres are almost universally defined by the histone variant CENP-A. In the holocentric nematode C. elegans, CENP-A deposition depends on the loading factor KNL-2. Depletion of either CENP-A or KNL-2 results in defects in centromere maintenance, chromosome condensation and kinetochore formation, leading to chromosome segregation failure. Here, we show that KNL-2 is phosphorylated by CDK-1 in vitro, and that mutation of three C-terminal phosphorylation sites causes chromosome segregation defects and an increase in embryonic lethality. In strains expressing phosphodeficient KNL-2, CENP-A and kinetochore proteins are properly localised, indicating that the role of KNL-2 in centromere maintenance is not affected. Instead, the mutant embryos exhibit reduced mitotic levels of condensin II on chromosomes and significant chromosome condensation impairment. Our findings separate the functions of KNL-2 in CENP-A loading and chromosome condensation, and demonstrate that KNL-2 phosphorylation regulates the cooperation between centromeric regions and the condensation machinery in C. elegans. This article has an associated First Person interview with the first author of the paper. Summary: Phosphorylation of the essential centromere protein KNL-2 is required for mitotic chromosome condensation, but not for the role of KNL-2 in centromere maintenance and kinetochore formation.
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Affiliation(s)
- Joanna M Wenda
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Reinier F Prosée
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Caroline Gabus
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
| | - Florian A Steiner
- Department of Molecular Biology and Institute for Genetics and Genomics in Geneva, Section of Biology, Faculty of Sciences, University of Geneva, 1211 Geneva, Switzerland
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22
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Salinas-Luypaert C, Allu PK, Logsdon GA, Dawicki-McKenna JM, Gambogi CW, Fachinetti D, Black BE. Gene replacement strategies validate the use of functional tags on centromeric chromatin and invalidate an essential role for CENP-A K124ub. Cell Rep 2021; 37:109924. [PMID: 34731637 PMCID: PMC8643106 DOI: 10.1016/j.celrep.2021.109924] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 08/31/2021] [Accepted: 10/12/2021] [Indexed: 12/17/2022] Open
Abstract
Functional tags are ubiquitous in cell biology, and for studies of one chromosomal locus, the centromere, tags have been remarkably useful. The centromere directs chromosome inheritance at cell division. The location of the centromere is defined by a histone H3 variant, CENP-A. The regulation of the chromatin assembly pathway essential for centromere inheritance and function includes posttranslational modification (PTM) of key components, including CENP-A itself. Others have recently called into question the use of functional tags, with the claim that at least two widely used tags obscured the essentiality of one particular PTM, CENP-AK124 ubiquitination (ub). Here, we employ three independent gene replacement strategies that eliminate large, lysine-containing tags to interrogate these claims. Using these approaches, we find no evidence to support an essential function of CENP-AK124ub. Our general methodology will be useful to validate discoveries permitted by powerful functional tagging schemes at the centromere and other cellular locations. Using three gene replacement strategies, Salinas-Luypaert et al. demonstrate that CENP-AK124ub is not essential for CENP-A function at centromeres. Thus, functional tags do not mask the role of K124 when it is mutated. These strategies can be employed to interrogate posttranslational modifications at the centromere and other cellular locations.
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Affiliation(s)
| | - Praveen Kumar Allu
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Glennis A Logsdon
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Jennine M Dawicki-McKenna
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Craig W Gambogi
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Program in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daniele Fachinetti
- Institut Curie, PSL University, CNRS, UMR 144, 26 rue d'Ulm, 75005, Paris, France.
| | - Ben E Black
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Program in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA.
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23
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Cai G, Yang Q, Sun W. RSF1 in cancer: interactions and functions. Cancer Cell Int 2021; 21:315. [PMID: 34147108 PMCID: PMC8214769 DOI: 10.1186/s12935-021-02012-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/10/2021] [Indexed: 12/25/2022] Open
Abstract
RSF1, remodelling and spacing factor 1, is an important interphase centromere protein and is overexpressed in many types of cancers and correlated with poor overall survival. RSF1 has functions mainly in maintaining chromosome stability, facilitating DNA repair, maintaining the protein homeostasis of RSF1 and suppressing the transcription of some oncogenes when RSF1 protein is expressed at an optimal level; however, RSF1 overexpression facilitates drug resistance and cell cycle checkpoint inhibition to prompt cancer proliferation and survival. The RSF1 expression level and gene background are crucial for RSF1 functions, which may explain why RSF1 has different functions in different cancer types. This review summarizes the functional domains of RSF1, the overexpression status of RSF1 and SNF2H in cancer based on the TCGA and GTEX databases, the cancer-related functions of RSF1 in interacting with H2Aub, HDAC1, CENP-A, PLK1, ATM, CENP-S, SNF2H, HBX, BubR1, cyclin E1, CBP and NF-κB and the potential clinical value of RSF1, which will lay a theoretical foundation for the structural biology study of RSF1 and application of RSF1 inhibitors, truncated RSF1 proteins and SNF2H inhibitors in the treatment of RSF1-overexpressing tumours.
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Affiliation(s)
- Guiyang Cai
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Qing Yang
- Department of Obstetrics and Gynecology, Shengjing Hospital of China Medical University, Shenyang, China.
| | - Wei Sun
- Department of Key Laboratory of Cell Biology, Ministry of Public Health and Key Laboratory of Medical Cell Biology, School of Life Sciences, China Medical University, Shenyang, China.
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24
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Abstract
Cancer is a complex disease characterized by loss of cellular homeostasis through genetic and epigenetic alterations. Emerging evidence highlights a role for histone variants and their dedicated chaperones in cancer initiation and progression. Histone variants are involved in processes as diverse as maintenance of genome integrity, nuclear architecture and cell identity. On a molecular level, histone variants add a layer of complexity to the dynamic regulation of transcription, DNA replication and repair, and mitotic chromosome segregation. Because these functions are critical to ensure normal proliferation and maintenance of cellular fate, cancer cells are defined by their capacity to subvert them. Hijacking histone variants and their chaperones is emerging as a common means to disrupt homeostasis across a wide range of cancers, particularly solid tumours. Here we discuss histone variants and histone chaperones as tumour-promoting or tumour-suppressive players in the pathogenesis of cancer.
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Affiliation(s)
| | - Dan Filipescu
- Icahn School of Medicine at Mount Sinai, New York, NY, USA
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25
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Navarro AP, Cheeseman IM. Kinetochore assembly throughout the cell cycle. Semin Cell Dev Biol 2021; 117:62-74. [PMID: 33753005 DOI: 10.1016/j.semcdb.2021.03.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/29/2022]
Abstract
The kinetochore plays an essential role in facilitating chromosome segregation during cell division. This massive protein complex assembles onto the centromere of chromosomes and enables their attachment to spindle microtubules during mitosis. The kinetochore also functions as a signaling hub to regulate cell cycle progression, and is crucial to ensuring the fidelity of chromosome segregation. Despite the fact that kinetochores are large and robust molecular assemblies, they are also highly dynamic structures that undergo structural and organizational changes throughout the cell cycle. This review will highlight our current understanding of kinetochore structure and function, focusing on the dynamic processes that underlie kinetochore assembly.
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Affiliation(s)
- Alexandra P Navarro
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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26
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Nagpal H, Fierz B. The Elusive Structure of Centro-Chromatin: Molecular Order or Dynamic Heterogenetity? J Mol Biol 2021; 433:166676. [PMID: 33065112 DOI: 10.1016/j.jmb.2020.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 01/09/2023]
Abstract
The centromere is an essential chromatin domain required for kinetochore recruitment and chromosome segregation in eukaryotes. To perform this role, centro-chromatin adopts a unique structure that provides access to kinetochore proteins and maintains stability under tension during mitosis. This is achieved by the presence of nucleosomes containing the H3 variant CENP-A, which also acts as the epigenetic mark defining the centromere. In this review, we discuss the role of CENP-A on the structure and dynamics of centromeric chromatin. We further discuss the impact of the CENP-A binding proteins CENP-C, CENP-N, and CENP-B on modulating centro-chromatin structure. Based on these findings we provide an overview of the higher order structure of the centromere.
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Affiliation(s)
- Harsh Nagpal
- Laboratory of Biophysical Chemistry of Macromolecules, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
| | - Beat Fierz
- Laboratory of Biophysical Chemistry of Macromolecules, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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27
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Centromere assembly and non-random sister chromatid segregation in stem cells. Essays Biochem 2021; 64:223-232. [PMID: 32406510 DOI: 10.1042/ebc20190066] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/21/2020] [Accepted: 04/30/2020] [Indexed: 01/17/2023]
Abstract
Asymmetric cell division (ACD) produces daughter cells with separate distinct cell fates and is critical for the development and regulation of multicellular organisms. Epigenetic mechanisms are key players in cell fate determination. Centromeres, epigenetically specified loci defined by the presence of the histone H3-variant, centromere protein A (CENP-A), are essential for chromosome segregation at cell division. ACDs in stem cells and in oocyte meiosis have been proposed to be reliant on centromere integrity for the regulation of the non-random segregation of chromosomes. It has recently been shown that CENP-A is asymmetrically distributed between the centromeres of sister chromatids in male and female Drosophila germline stem cells (GSCs), with more CENP-A on sister chromatids to be segregated to the GSC. This imbalance in centromere strength correlates with the temporal and asymmetric assembly of the mitotic spindle and potentially orientates the cell to allow for biased sister chromatid retention in stem cells. In this essay, we discuss the recent evidence for asymmetric sister centromeres in stem cells. Thereafter, we discuss mechanistic avenues to establish this sister centromere asymmetry and how it ultimately might influence cell fate.
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28
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Dattoli AA, Carty BL, Kochendoerfer AM, Morgan C, Walshe AE, Dunleavy EM. Asymmetric assembly of centromeres epigenetically regulates stem cell fate. J Cell Biol 2020; 219:133868. [PMID: 32328637 PMCID: PMC7147107 DOI: 10.1083/jcb.201910084] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 12/10/2019] [Accepted: 02/10/2020] [Indexed: 02/07/2023] Open
Abstract
Centromeres are epigenetically defined by CENP-A–containing chromatin and are essential for cell division. Previous studies suggest asymmetric inheritance of centromeric proteins upon stem cell division; however, the mechanism and implications of selective chromosome segregation remain unexplored. We show that Drosophila female germline stem cells (GSCs) and neuroblasts assemble centromeres after replication and before segregation. Specifically, CENP-A deposition is promoted by CYCLIN A, while excessive CENP-A deposition is prevented by CYCLIN B, through the HASPIN kinase. Furthermore, chromosomes inherited by GSCs incorporate more CENP-A, making stronger kinetochores that capture more spindle microtubules and bias segregation. Importantly, symmetric incorporation of CENP-A on sister chromatids via HASPIN knockdown or overexpression of CENP-A, either alone or together with its assembly factor CAL1, drives stem cell self-renewal. Finally, continued CENP-A assembly in differentiated cells is nonessential for egg development. Our work shows that centromere assembly epigenetically drives GSC maintenance and occurs before oocyte meiosis.
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Affiliation(s)
- Anna Ada Dattoli
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
| | - Ben L Carty
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
| | - Antje M Kochendoerfer
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
| | - Conall Morgan
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
| | - Annie E Walshe
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
| | - Elaine M Dunleavy
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland, UK
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29
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Milagre I, Pereira C, Oliveira RA, Jansen LET. Reprogramming of human cells to pluripotency induces CENP-A chromatin depletion. Open Biol 2020; 10:200227. [PMID: 33081635 PMCID: PMC7653353 DOI: 10.1098/rsob.200227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Pluripotent stem cells (PSCs) are central to development as they are the precursors of all cell types in the embryo. Therefore, maintaining a stable karyotype is essential, both for their physiological role as well as for their use in regenerative medicine. Karyotype abnormalities in PSCs in culture are common but the underlying causes remain unknown. To gain insight, we explore the composition of the centromere and kinetochore in human embryonic and induced PSCs. Centromere function depends on CENP-A nucleosome-defined chromatin. We show that while PSCs maintain abundant pools of CENP-A, CENP-C and CENP-T, these essential centromere components are strongly reduced at stem cell centromeres. Outer kinetochore recruitment is also impaired to a lesser extent, indicating an overall weaker kinetochore while the inner centromere protein Aurora B remains unaffected. We further show that, similar to differentiated human cells, CENP-A chromatin assembly in PSCs requires transition into G1 phase. Finally, reprogramming experiments indicate that reduction of centromeric CENP-A levels is an early event during dedifferentiation, coinciding with global chromatin remodelling. Our characterization of centromeres in human stem cells suggests a possible link between impaired centromere function and stem cell aneuploidies.
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Affiliation(s)
- Inês Milagre
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Carolina Pereira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Raquel A Oliveira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Lars E T Jansen
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.,Department of Biochemistry, University of Oxford, OX1, 3QU, UK
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30
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Hoffmann S, Izquierdo HM, Gamba R, Chardon F, Dumont M, Keizer V, Hervé S, McNulty SM, Sullivan BA, Manel N, Fachinetti D. A genetic memory initiates the epigenetic loop necessary to preserve centromere position. EMBO J 2020; 39:e105505. [PMID: 32945564 PMCID: PMC7560200 DOI: 10.15252/embj.2020105505] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 08/10/2020] [Accepted: 08/25/2020] [Indexed: 12/18/2022] Open
Abstract
Centromeres are built on repetitive DNA sequences (CenDNA) and a specific chromatin enriched with the histone H3 variant CENP‐A, the epigenetic mark that identifies centromere position. Here, we interrogate the importance of CenDNA in centromere specification by developing a system to rapidly remove and reactivate CENP‐A (CENP‐AOFF/ON). Using this system, we define the temporal cascade of events necessary to maintain centromere position. We unveil that CENP‐B bound to CenDNA provides memory for maintenance on human centromeres by promoting de novo CENP‐A deposition. Indeed, lack of CENP‐B favors neocentromere formation under selective pressure. Occasionally, CENP‐B triggers centromere re‐activation initiated by CENP‐C, but not CENP‐A, recruitment at both ectopic and native centromeres. This is then sufficient to initiate the CENP‐A‐based epigenetic loop. Finally, we identify a population of CENP‐A‐negative, CENP‐B/C‐positive resting CD4+ T cells capable to re‐express and reassembles CENP‐A upon cell cycle entry, demonstrating the physiological importance of the genetic memory.
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Affiliation(s)
| | | | - Riccardo Gamba
- Institut Curie, CNRS, UMR 144, PSL Research University, Paris, France
| | - Florian Chardon
- Institut Curie, CNRS, UMR 144, PSL Research University, Paris, France
| | - Marie Dumont
- Institut Curie, CNRS, UMR 144, PSL Research University, Paris, France
| | - Veer Keizer
- Institut Curie, CNRS, UMR 144, PSL Research University, Paris, France
| | - Solène Hervé
- Institut Curie, CNRS, UMR 144, PSL Research University, Paris, France
| | - Shannon M McNulty
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Beth A Sullivan
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Nicolas Manel
- Institut Curie, PSL Research University, INSERM U932, Paris, France
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31
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Hinshaw SM, Harrison SC. The Structural Basis for Kinetochore Stabilization by Cnn1/CENP-T. Curr Biol 2020; 30:3425-3431.e3. [PMID: 32679099 PMCID: PMC11816742 DOI: 10.1016/j.cub.2020.06.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/22/2022]
Abstract
Chromosome segregation depends on a regulated connection between spindle microtubules and centromeric DNA. The kinetochore mediates this connection and ensures it persists during anaphase, when sister chromatids must transit into daughter cells uninterrupted. The Ctf19 complex (Ctf19c) forms the centromeric base of the kinetochore in budding yeast. Biochemical experiments show that Ctf19c members associate hierarchically when purified from cell extract [1], an observation that is mostly explained by the structure of the complex [2]. The Ctf3 complex (Ctf3c), which is not required for the assembly of most other Ctf19c factors, disobeys the biochemical assembly hierarchy when observed in dividing cells that lack more basal components [3]. Thus, the biochemical experiments do not completely recapitulate the logic of centromeric Ctf19c assembly. We now present a high-resolution structure of the Ctf3c bound to the Cnn1-Wip1 heterodimer. Associated live-cell imaging experiments provide a mechanism for Ctf3c and Cnn1-Wip1 recruitment to the kinetochore. The mechanism suggests feedback regulation of Ctf19c assembly and unanticipated similarities in kinetochore organization between yeast and vertebrates.
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Affiliation(s)
- Stephen M Hinshaw
- Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, USA.
| | - Stephen C Harrison
- Harvard Medical School, Howard Hughes Medical Institute, Boston, MA, USA
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32
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Wong CYY, Lee BCH, Yuen KWY. Epigenetic regulation of centromere function. Cell Mol Life Sci 2020; 77:2899-2917. [PMID: 32008088 PMCID: PMC11105045 DOI: 10.1007/s00018-020-03460-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 12/23/2019] [Accepted: 01/10/2020] [Indexed: 12/20/2022]
Abstract
The centromere is a specialized region on the chromosome that directs equal chromosome segregation. Centromeres are usually not defined by DNA sequences alone. How centromere formation and function are determined by epigenetics is still not fully understood. Active centromeres are often marked by the presence of centromeric-specific histone H3 variant, centromere protein A (CENP-A). How CENP-A is assembled into the centromeric chromatin during the cell cycle and propagated to the next cell cycle or the next generation to maintain the centromere function has been intensively investigated. In this review, we summarize current understanding of how post-translational modifications of CENP-A and other centromere proteins, centromeric and pericentric histone modifications, non-coding transcription and transcripts contribute to centromere function, and discuss their intricate relationships and potential feedback mechanisms.
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Affiliation(s)
- Charmaine Yan Yu Wong
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong, China
| | - Bernard Chi Hang Lee
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong, China
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong, China.
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33
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Mahlke MA, Nechemia-Arbely Y. Guarding the Genome: CENP-A-Chromatin in Health and Cancer. Genes (Basel) 2020; 11:genes11070810. [PMID: 32708729 PMCID: PMC7397030 DOI: 10.3390/genes11070810] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/10/2020] [Accepted: 07/15/2020] [Indexed: 02/07/2023] Open
Abstract
Faithful chromosome segregation is essential for the maintenance of genomic integrity and requires functional centromeres. Centromeres are epigenetically defined by the histone H3 variant, centromere protein A (CENP-A). Here we highlight current knowledge regarding CENP-A-containing chromatin structure, specification of centromere identity, regulation of CENP-A deposition and possible contribution to cancer formation and/or progression. CENP-A overexpression is common among many cancers and predicts poor prognosis. Overexpression of CENP-A increases rates of CENP-A deposition ectopically at sites of high histone turnover, occluding CCCTC-binding factor (CTCF) binding. Ectopic CENP-A deposition leads to mitotic defects, centromere dysfunction and chromosomal instability (CIN), a hallmark of cancer. CENP-A overexpression is often accompanied by overexpression of its chaperone Holliday Junction Recognition Protein (HJURP), leading to epigenetic addiction in which increased levels of HJURP and CENP-A become necessary to support rapidly dividing p53 deficient cancer cells. Alterations in CENP-A posttranslational modifications are also linked to chromosome segregation errors and CIN. Collectively, CENP-A is pivotal to genomic stability through centromere maintenance, perturbation of which can lead to tumorigenesis.
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Affiliation(s)
- Megan A. Mahlke
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA;
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Yael Nechemia-Arbely
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA;
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Correspondence: ; Tel.: +1-412-623-3228; Fax: +1-412-623-7828
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34
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Das A, Black BE, Lampson MA. Maternal inheritance of centromeres through the germline. Curr Top Dev Biol 2020; 140:35-54. [PMID: 32591081 DOI: 10.1016/bs.ctdb.2020.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
The centromere directs chromosome segregation but is not itself genetically encoded. In most species, centromeres are epigenetically defined by the presence of a histone H3 variant CENP-A, independent of the underlying DNA sequence. Therefore, to maintain centromeres and ensure accurate chromosome segregation, CENP-A nucleosomes must be inherited across generations through the germline. In this chapter we discuss three aspects of maternal centromere inheritance. First, we propose mechanisms for maintaining CENP-A nucleosomes through the prolonged prophase arrest in mammalian oocytes. Second, we review mechanisms by which selfish centromeres bias their transmission through female meiosis. Third, we discuss regulation of centromere size through early embryonic development.
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Affiliation(s)
- Arunika Das
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States; Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ben E Black
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
| | - Michael A Lampson
- Department of Biology, University of Pennsylvania, Philadelphia, PA, United States.
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35
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Medina‐Pritchard B, Lazou V, Zou J, Byron O, Abad MA, Rappsilber J, Heun P, Jeyaprakash AA. Structural basis for centromere maintenance by Drosophila CENP-A chaperone CAL1. EMBO J 2020; 39:e103234. [PMID: 32134144 PMCID: PMC7110144 DOI: 10.15252/embj.2019103234] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 01/25/2020] [Accepted: 02/11/2020] [Indexed: 01/08/2023] Open
Abstract
Centromeres are microtubule attachment sites on chromosomes defined by the enrichment of histone variant CENP-A-containing nucleosomes. To preserve centromere identity, CENP-A must be escorted to centromeres by a CENP-A-specific chaperone for deposition. Despite this essential requirement, many eukaryotes differ in the composition of players involved in centromere maintenance, highlighting the plasticity of this process. In humans, CENP-A recognition and centromere targeting are achieved by HJURP and the Mis18 complex, respectively. Using X-ray crystallography, we here show how Drosophila CAL1, an evolutionarily distinct CENP-A histone chaperone, binds both CENP-A and the centromere receptor CENP-C without the requirement for the Mis18 complex. While an N-terminal CAL1 fragment wraps around CENP-A/H4 through multiple physical contacts, a C-terminal CAL1 fragment directly binds a CENP-C cupin domain dimer. Although divergent at the primary structure level, CAL1 thus binds CENP-A/H4 using evolutionarily conserved and adaptive structural principles. The CAL1 binding site on CENP-C is strategically positioned near the cupin dimerisation interface, restricting binding to just one CAL1 molecule per CENP-C dimer. Overall, by demonstrating how CAL1 binds CENP-A/H4 and CENP-C, we provide key insights into the minimalistic principles underlying centromere maintenance.
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Affiliation(s)
| | - Vasiliki Lazou
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Juan Zou
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Olwyn Byron
- School of Life SciencesUniversity of GlasgowGlasgowUK
| | - Maria A Abad
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
| | - Juri Rappsilber
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK,Institute of BiotechnologyTechnische Universität BerlinBerlinGermany
| | - Patrick Heun
- Wellcome Centre for Cell BiologyUniversity of EdinburghEdinburghUK
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36
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Murillo-Pineda M, Jansen LET. Genetics, epigenetics and back again: Lessons learned from neocentromeres. Exp Cell Res 2020; 389:111909. [PMID: 32068000 DOI: 10.1016/j.yexcr.2020.111909] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/04/2020] [Accepted: 02/10/2020] [Indexed: 12/12/2022]
Abstract
The duplication and segregation of the genome during cell division is crucial to maintain cell identity, development of organisms and tissue maintenance. Centromeres are at the basis of accurate chromosome segregation as they define the site of assembly of the kinetochore, a large complex of proteins that attaches to spindle microtubules driving chromosome movement during cell division. Here we summarize nearly 40 years of research focussed on centromere specification and the role of local cis elements in creating a stable centromere. Initial discoveries in budding yeast in the 1980s opened up the field and revealed essential DNA sequence elements that define centromere position and function. Further work in humans discovered a centromeric DNA sequence-specific binding protein and centromeric α-satellite DNA was found to have the capacity to seed centromeres de novo. Despite the early indication of genetic elements as drivers of centromere specification, the discovery in the nineties of neocentromeres that form on unrelated DNA sequences, shifted the focus to epigenetic mechanisms. While specific sequence elements appeared non-essential, the histone H3 variant CENP-A was identified as a crucial component in centromere specification. Neocentromeres, occurring naturally or induced experimentally, have become an insightful tool to understand the mechanisms for centromere specification and will be the focus of this review. They have helped to define the strong epigenetic chromatin-based component underlying centromere inheritance but also provide new opportunities to understand the enigmatic, yet crucial role that DNA sequence elements play in centromere function and inheritance.
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Affiliation(s)
| | - Lars E T Jansen
- Department of Biochemistry, University of Oxford, OX1 3QU, United Kingdom.
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37
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Hori T, Fukagawa T. Artificial generation of centromeres and kinetochores to understand their structure and function. Exp Cell Res 2020; 389:111898. [PMID: 32035949 DOI: 10.1016/j.yexcr.2020.111898] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/18/2020] [Accepted: 02/05/2020] [Indexed: 01/19/2023]
Abstract
The centromere is an essential genomic region that provides the surface to form the kinetochore, which binds to the spindle microtubes to mediate chromosome segregation during mitosis and meiosis. Centromeres of most organisms possess highly repetitive sequences, making it difficult to study these loci. However, an unusual centromere called a "neocentromere," which does not contain repetitive sequences, was discovered in a patient and can be generated experimentally. Recent advances in genome biology techniques allow us to analyze centromeric chromatin using neocentromeres. In addition to neocentromeres, artificial kinetochores have been generated on non-centromeric loci, using protein tethering systems. These are powerful tools to understand the mechanism of the centromere specification and kinetochore assembly. In this review, we introduce recent studies utilizing the neocentromeres and artificial kinetochores and discuss current problems in centromere biology.
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Affiliation(s)
- Tetsuya Hori
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan.
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan.
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Mitra S, Bodor DL, David AF, Abdul-Zani I, Mata JF, Neumann B, Reither S, Tischer C, Jansen LET. Genetic screening identifies a SUMO protease dynamically maintaining centromeric chromatin. Nat Commun 2020; 11:501. [PMID: 31980633 PMCID: PMC6981222 DOI: 10.1038/s41467-019-14276-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 12/18/2019] [Indexed: 12/27/2022] Open
Abstract
Centromeres are defined by a self-propagating chromatin structure based on stable inheritance of CENP-A containing nucleosomes. Here, we present a genetic screen coupled to pulse-chase labeling that allow us to identify proteins selectively involved in deposition of nascent CENP-A or in long-term transmission of chromatin-bound CENP-A. These include factors with known roles in DNA replication, repair, chromatin modification, and transcription, revealing a broad set of chromatin regulators that impact on CENP-A dynamics. We further identify the SUMO-protease SENP6 as a key factor, not only controlling CENP-A stability but virtually the entire centromere and kinetochore. Loss of SENP6 results in hyper-SUMOylation of CENP-C and CENP-I but not CENP-A itself. SENP6 activity is required throughout the cell cycle, suggesting that a dynamic SUMO cycle underlies a continuous surveillance of the centromere complex that in turn ensures stable transmission of CENP-A chromatin.
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Affiliation(s)
- Sreyoshi Mitra
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
- Instituto Gulbenkian de Ciência, 2780-156, Oeiras, Portugal
| | - Dani L Bodor
- Instituto Gulbenkian de Ciência, 2780-156, Oeiras, Portugal
- MRC-Laboratory for Molecular Cell Biology, UCL, London, WC1E 6BT, UK
| | - Ana F David
- Instituto Gulbenkian de Ciência, 2780-156, Oeiras, Portugal
- Institute of Molecular Biotechnology, Dr. Bohr-Gasse 3, 1030, Vienna, Austria
| | - Izma Abdul-Zani
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - João F Mata
- Instituto Gulbenkian de Ciência, 2780-156, Oeiras, Portugal
| | - Beate Neumann
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, D-69117, Heidelberg, Germany
| | - Sabine Reither
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, D-69117, Heidelberg, Germany
| | - Christian Tischer
- European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, D-69117, Heidelberg, Germany
| | - Lars E T Jansen
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK.
- Instituto Gulbenkian de Ciência, 2780-156, Oeiras, Portugal.
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Huang A, Kremser L, Schuler F, Wilflingseder D, Lindner H, Geley S, Lusser A. Phosphorylation of Drosophila CENP-A on serine 20 regulates protein turn-over and centromere-specific loading. Nucleic Acids Res 2019; 47:10754-10770. [PMID: 31535131 PMCID: PMC6847487 DOI: 10.1093/nar/gkz809] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/06/2019] [Accepted: 09/11/2019] [Indexed: 12/30/2022] Open
Abstract
Centromeres are specialized chromosomal regions epigenetically defined by the presence of the histone H3 variant CENP-A. CENP-A is required for kinetochore formation which is essential for chromosome segregation during mitosis. Spatial restriction of CENP-A to the centromere is tightly controlled. Its overexpression results in ectopic incorporation and the formation of potentially deleterious neocentromeres in yeast, flies and in various human cancers. While the contribution of posttranslational modifications of CENP-A to these processes has been studied in yeast and mammals to some extent, very little is known about Drosophila melanogaster. Here, we show that CENP-A is phosphorylated at serine 20 (S20) by casein kinase II and that in mitotic cells, the phosphorylated form is enriched on chromatin. Importantly, our results reveal that S20 phosphorylation regulates the turn-over of prenucleosomal CENP-A by the SCFPpa-proteasome pathway and that phosphorylation promotes removal of CENP-A from ectopic but not from centromeric sites in chromatin. We provide multiple lines of evidence for a crucial role of S20 phosphorylation in controlling restricted incorporation of CENP-A into centromeric chromatin in flies. Modulation of the phosphorylation state of S20 may provide the cells with a means to fine-tune CENP-A levels in order to prevent deleterious loading to extra-centromeric sites.
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Affiliation(s)
- Anming Huang
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Leopold Kremser
- Institute of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Austria
| | - Fabian Schuler
- Institute of Developmental Immunology, Biocenter, Medical University of Innsbruck, Austria
| | - Doris Wilflingseder
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Austria
| | - Herbert Lindner
- Institute of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Austria
| | - Stephan Geley
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Austria
| | - Alexandra Lusser
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Austria
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Boudichevskaia A, Houben A, Fiebig A, Prochazkova K, Pecinka A, Lermontova I. Depletion of KNL2 Results in Altered Expression of Genes Involved in Regulation of the Cell Cycle, Transcription, and Development in Arabidopsis. Int J Mol Sci 2019; 20:ijms20225726. [PMID: 31731608 PMCID: PMC6888302 DOI: 10.3390/ijms20225726] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/07/2019] [Accepted: 11/11/2019] [Indexed: 11/17/2022] Open
Abstract
Centromeres contain specialized nucleosomes at which histone H3 is partially replaced by the centromeric histone H3 variant cenH3 that is required for the assembly, maintenance, and proper function of kinetochores during mitotic and meiotic divisions. Previously, we identified a KINETOCHORE NULL 2 (KNL2) of Arabidopsis thaliana that is involved in the licensing of centromeres for the cenH3 recruitment. We also demonstrated that a knockout mutant for KNL2 shows mitotic and meiotic defects, slower development, reduced growth rate, and fertility. To analyze an effect of KNL2 mutation on global gene transcription of Arabidopsis, we performed RNA-sequencing experiments using seedling and flower bud tissues of knl2 and wild-type plants. The transcriptome data analysis revealed a high number of differentially expressed genes (DEGs) in knl2 plants. The set was enriched in genes involved in the regulation of the cell cycle, transcription, development, and DNA damage repair. In addition to comprehensive information regarding the effects of KNL2 mutation on the global gene expression, physiological changes in plants are also presented, which provides an integrated understanding of the critical role played by KNL2 in plant growth and development.
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Affiliation(s)
- Anastassia Boudichevskaia
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstrasse 3, D-06466 Seeland, Germany; (A.H.); (A.F.)
- Correspondence: (A.B.); (I.L.); Tel.: +49/39482 5477 (A.B.); +49/39482 5570 (I.L.)
| | - Andreas Houben
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstrasse 3, D-06466 Seeland, Germany; (A.H.); (A.F.)
| | - Anne Fiebig
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstrasse 3, D-06466 Seeland, Germany; (A.H.); (A.F.)
| | - Klara Prochazkova
- Institute of Experimental Botany, Czech Acad Sci, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Šlechtitelů 31, CZ-77900 Olomouc, Czech Republic; (K.P.); (A.P.)
| | - Ales Pecinka
- Institute of Experimental Botany, Czech Acad Sci, Centre of the Region Haná for Biotechnological and Agricultural Research (CRH), Šlechtitelů 31, CZ-77900 Olomouc, Czech Republic; (K.P.); (A.P.)
| | - Inna Lermontova
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, Corrensstrasse 3, D-06466 Seeland, Germany; (A.H.); (A.F.)
- Mendel Centre for Plant Genomics and Proteomics, CEITEC, Masaryk University, Brno CZ-62500, Czech Republic
- Correspondence: (A.B.); (I.L.); Tel.: +49/39482 5477 (A.B.); +49/39482 5570 (I.L.)
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Lera RF, Norman RX, Dumont M, Dennee A, Martin‐Koob J, Fachinetti D, Burkard ME. Plk1 protects kinetochore-centromere architecture against microtubule pulling forces. EMBO Rep 2019; 20:e48711. [PMID: 31468671 PMCID: PMC6776907 DOI: 10.15252/embr.201948711] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/03/2019] [Accepted: 08/09/2019] [Indexed: 12/26/2022] Open
Abstract
During mitosis, sister chromatids attach to microtubules which generate ~ 700 pN pulling force focused on the centromere. We report that chromatin-localized signals generated by Polo-like kinase 1 (Plk1) maintain the integrity of the kinetochore and centromere against this force. Without sufficient Plk1 activity, chromosomes become misaligned after normal condensation and congression. These chromosomes are silent to the mitotic checkpoint, and many lag and mis-segregate in anaphase. Their centromeres and kinetochores lack CENP-A, CENP-C, CENP-T, Hec1, Nuf2, and Knl1; however, CENP-B is retained. CENP-A loss occurs coincident with secondary misalignment and anaphase onset. This disruption occurs asymmetrically prior to anaphase and requires tension generated by microtubules. Mechanistically, centromeres highly recruit PICH DNA helicase and PICH depletion restores kinetochore disruption in pre-anaphase cells. Furthermore, anaphase defects are significantly reduced by tethering Plk1 to chromatin, including H2B, and INCENP, but not to CENP-A. Taken as a whole, this demonstrates that Plk1 signals are crucial for stabilizing centromeric architecture against tension.
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Affiliation(s)
- Robert F Lera
- Division of Hematology/OncologyDepartment of MedicineSchool of Medicine and Public HealthUniversity of WisconsinMadisonWIUSA
- UW Carbone Cancer CenterUniversity of WisconsinMadisonWIUSA
| | - Roshan X Norman
- Division of Hematology/OncologyDepartment of MedicineSchool of Medicine and Public HealthUniversity of WisconsinMadisonWIUSA
- UW Carbone Cancer CenterUniversity of WisconsinMadisonWIUSA
| | - Marie Dumont
- Institut CurieCNRS, UMR 144PSL Research UniversityParisFrance
| | - Alexandra Dennee
- Division of Hematology/OncologyDepartment of MedicineSchool of Medicine and Public HealthUniversity of WisconsinMadisonWIUSA
- UW Carbone Cancer CenterUniversity of WisconsinMadisonWIUSA
| | - Joanne Martin‐Koob
- Division of Hematology/OncologyDepartment of MedicineSchool of Medicine and Public HealthUniversity of WisconsinMadisonWIUSA
- UW Carbone Cancer CenterUniversity of WisconsinMadisonWIUSA
| | | | - Mark E Burkard
- Division of Hematology/OncologyDepartment of MedicineSchool of Medicine and Public HealthUniversity of WisconsinMadisonWIUSA
- UW Carbone Cancer CenterUniversity of WisconsinMadisonWIUSA
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Pan D, Walstein K, Take A, Bier D, Kaiser N, Musacchio A. Mechanism of centromere recruitment of the CENP-A chaperone HJURP and its implications for centromere licensing. Nat Commun 2019; 10:4046. [PMID: 31492860 PMCID: PMC6731319 DOI: 10.1038/s41467-019-12019-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 08/16/2019] [Indexed: 12/20/2022] Open
Abstract
Nucleosomes containing the histone H3 variant CENP-A are the epigenetic mark of centromeres, the kinetochore assembly sites required for chromosome segregation. HJURP is the CENP-A chaperone, which associates with Mis18α, Mis18β, and M18BP1 to target centromeres and deposit new CENP-A. How these proteins interact to promote CENP-A deposition remains poorly understood. Here we show that two repeats in human HJURP proposed to be functionally distinct are in fact interchangeable and bind concomitantly to the 4:2:2 Mis18α:Mis18β:M18BP1 complex without dissociating it. HJURP binds CENP-A:H4 dimers, and therefore assembly of CENP-A:H4 tetramers must be performed by two Mis18αβ:M18BP1:HJURP complexes, or by the same complex in consecutive rounds. The Mis18α N-terminal tails blockade two identical HJURP-repeat binding sites near the Mis18αβ C-terminal helices. These were identified by photo-cross-linking experiments and mutated to separate Mis18 from HJURP centromere recruitment. Our results identify molecular underpinnings of eukaryotic chromosome inheritance and shed light on how centromeres license CENP-A deposition. The CENP-A chaperone HJURP associates with Mis18α, Mis18β, and M18BP1 to target centromeres and deposit new CENP-A. Here the authors provide evidence that two repeats in human HJURP previously proposed to be functionally distinct are interchangeable and bind concomitantly to the 4:2:2 Mis18α:Mis18β:M18BP1 complex without dissociating it.
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Affiliation(s)
- Dongqing Pan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany.
| | - Kai Walstein
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Annika Take
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - David Bier
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Nadine Kaiser
- Department of Chemical Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227, Dortmund, Germany. .,Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstrasse, 45141, Essen, Germany.
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43
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Sharma AB, Dimitrov S, Hamiche A, Van Dyck E. Centromeric and ectopic assembly of CENP-A chromatin in health and cancer: old marks and new tracks. Nucleic Acids Res 2019; 47:1051-1069. [PMID: 30590707 PMCID: PMC6379705 DOI: 10.1093/nar/gky1298] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/13/2018] [Accepted: 12/18/2018] [Indexed: 12/20/2022] Open
Abstract
The histone H3 variant CENP-A confers epigenetic identity to the centromere and plays crucial roles in the assembly and function of the kinetochore, thus ensuring proper segregation of our chromosomes. CENP-A containing nucleosomes exhibit unique structural specificities and lack the complex profile of gene expression-associated histone posttranslational modifications found in canonical histone H3 and the H3.3 variant. CENP-A mislocalization into noncentromeric regions resulting from its overexpression leads to chromosomal segregation aberrations and genome instability. Overexpression of CENP-A is a feature of many cancers and is associated with malignant progression and poor outcome. The recent years have seen impressive progress in our understanding of the mechanisms that orchestrate CENP-A deposition at native centromeres and ectopic loci. They have witnessed the description of novel, heterotypic CENP-A/H3.3 nucleosome particles and the exploration of the phenotypes associated with the deregulation of CENP-A and its chaperones in tumor cells. Here, we review the structural specificities of CENP-A nucleosomes, the epigenetic features that characterize the centrochromatin and the mechanisms and factors that orchestrate CENP-A deposition at centromeres. We then review our knowledge of CENP-A ectopic distribution, highlighting experimental strategies that have enabled key discoveries. Finally, we discuss the implications of deregulated CENP-A in cancer.
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Affiliation(s)
- Abhishek Bharadwaj Sharma
- NORLUX Neuro-Oncology Laboratory, Department of Oncology, Luxembourg Institute of Health (LIH), 84 Val Fleuri, L-1526 Luxembourg, Luxembourg
| | - Stefan Dimitrov
- Université Grenoble Alpes, CNRS UMR 5309, INSERM U1209, Institute for Advanced Biosciences (IAB), Site Santé-Allée des Alpes, 38700 La Tronche, France.,Izmir Biomedicine and Genome Center, İzmir, Turkey
| | - Ali Hamiche
- Département de Génomique Fonctionnelle et Cancer, Institut de Génétique et Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg, CNRS, INSERM, 67404 Illkirch Cedex, France
| | - Eric Van Dyck
- NORLUX Neuro-Oncology Laboratory, Department of Oncology, Luxembourg Institute of Health (LIH), 84 Val Fleuri, L-1526 Luxembourg, Luxembourg
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44
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DNA replication acts as an error correction mechanism to maintain centromere identity by restricting CENP-A to centromeres. Nat Cell Biol 2019; 21:743-754. [PMID: 31160708 DOI: 10.1038/s41556-019-0331-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 04/18/2019] [Indexed: 12/17/2022]
Abstract
Chromatin assembled with the histone H3 variant CENP-A is the heritable epigenetic determinant of human centromere identity. Using genome-wide mapping and reference models for 23 human centromeres, CENP-A binding sites are identified within the megabase-long, repetitive α-satellite DNAs at each centromere. CENP-A is shown in early G1 to be assembled into nucleosomes within each centromere and onto 11,390 transcriptionally active sites on the chromosome arms. DNA replication is demonstrated to remove ectopically loaded, non-centromeric CENP-A. In contrast, tethering of centromeric CENP-A to the sites of DNA replication through the constitutive centromere associated network (CCAN) is shown to enable precise reloading of centromere-bound CENP-A onto the same DNA sequences as in its initial prereplication loading. Thus, DNA replication acts as an error correction mechanism for maintaining centromere identity through its removal of non-centromeric CENP-A coupled with CCAN-mediated retention and precise reloading of centromeric CENP-A.
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45
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The nucleosomes that mark centromere location on chromosomes old and new. Essays Biochem 2019; 63:15-27. [DOI: 10.1042/ebc20180060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/07/2019] [Accepted: 03/13/2019] [Indexed: 01/02/2023]
Abstract
Abstract
Proper segregation of chromosomes is an essential component of cell division. The centromere is the locus at which the kinetochore—the proteinaceous complex that ties chromosomes to microtubules—forms during mitosis and meiosis. Thus, the centromere is critical for equal segregation of chromosomes. The centromere is characterized by both protein and DNA elements: the histone H3 variant CENP-A epigenetically defines the location of the centromere while centromeric DNA sequences are neither necessary nor sufficient for centromere function. Paradoxically, the DNA sequences play a critical role in new centromere formation. In this essay, we discuss the contribution of both epigenetics and genetics at the centromere. Understanding these contributions is vital to efforts to control centromere formation on synthetic/artificial chromosomes and centromere strength on natural ones.
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46
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Remnant L, Booth DG, Vargiu G, Spanos C, Kerr ARW, Earnshaw WC. In vitro BioID: mapping the CENP-A microenvironment with high temporal and spatial resolution. Mol Biol Cell 2019; 30:1314-1325. [PMID: 30892990 PMCID: PMC6724601 DOI: 10.1091/mbc.e18-12-0799] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The centromere is located at the primary constriction of condensed chromosomes where it acts as a platform regulating chromosome segregation. The histone H3 variant CENP-A is the foundation for kinetochore formation. CENP-A directs the formation of a highly dynamic molecular neighborhood whose temporal characterization during mitosis remains a challenge due to limitations in available techniques. BioID is a method that exploits a “promiscuous” biotin ligase (BirA118R or BirA*) to identify proteins within close proximity to a fusion protein of interest. As originally described, cells expressing BirA* fusions were exposed to high biotin concentrations for 24 h during which the ligase transferred activated biotin (BioAmp) to other proteins within the immediate vicinity. The protein neighborhood could then be characterized by streptavidin-based purification and mass spectrometry. Here we describe a further development to this technique, allowing CENP-A interactors to be characterized within only a few minutes, in an in vitro reaction in lysed cells whose physiological progression is “frozen.” This approach, termed in vitro BioID (ivBioID), has the potential to study the molecular neighborhood of any structural protein whose interactions change either during the cell cycle or in response to other changes in cell physiology.
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Affiliation(s)
- Lucy Remnant
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology and
| | - Daniel G Booth
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology and.,Centre for Brain Discovery Sciences, University of Edinburgh, Edinburgh EH16 4SB, UK
| | - Giulia Vargiu
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology and
| | - Christos Spanos
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology and
| | - Alastair R W Kerr
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology and
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Ohzeki J, Larionov V, Earnshaw WC, Masumoto H. De novo formation and epigenetic maintenance of centromere chromatin. Curr Opin Cell Biol 2019; 58:15-25. [PMID: 30654232 DOI: 10.1016/j.ceb.2018.12.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 11/30/2018] [Accepted: 12/07/2018] [Indexed: 12/12/2022]
Abstract
Accurate chromosome segregation is essential for cell proliferation. The centromere is a specialized chromosomal locus, on which the kinetochore structure is formed. The centromere/kinetochore is required for the equal separation of sister chromatids to daughter cells. Here, we review recent findings on centromere-specific chromatin, including its constitutive protein components, its de novo formation and maintenance mechanisms, and our progress in analyses with synthetic human artificial chromosomes (HACs).
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Affiliation(s)
- Junichirou Ohzeki
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu 292-0818, Japan
| | - Vladimir Larionov
- Genome Structure and Function Group, Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Hiroshi Masumoto
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu 292-0818, Japan.
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48
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French BT, Straight AF. CDK phosphorylation of Xenopus laevis M18BP1 promotes its metaphase centromere localization. EMBO J 2019; 38:embj.2018100093. [PMID: 30606714 DOI: 10.15252/embj.2018100093] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 12/07/2018] [Accepted: 12/11/2018] [Indexed: 01/08/2023] Open
Abstract
Chromosome segregation requires the centromere, the site on chromosomes where kinetochores assemble in mitosis to attach chromosomes to the mitotic spindle. Centromere identity is defined epigenetically by the presence of nucleosomes containing the histone H3 variant CENP-A. New CENP-A nucleosome assembly occurs at the centromere every cell cycle during G1, but how CENP-A nucleosome assembly is spatially and temporally restricted remains poorly understood. Centromere recruitment of factors required for CENP-A assembly is mediated in part by the three-protein Mis18 complex (Mis18α, Mis18β, M18BP1). Here, we show that Xenopus M18BP1 localizes to centromeres during metaphase-prior to CENP-A assembly-by binding to CENP-C using a highly conserved SANTA domain. We find that Cdk phosphorylation of M18BP1 is necessary for M18BP1 to bind CENP-C and localize to centromeres in metaphase. Surprisingly, mutations which disrupt the metaphase M18BP1/CENP-C interaction cause defective nuclear localization of M18BP1 in interphase, resulting in defective CENP-A nucleosome assembly. We propose that M18BP1 may identify centromeric sites in metaphase for subsequent CENP-A nucleosome assembly in interphase.
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Affiliation(s)
- Bradley T French
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
| | - Aaron F Straight
- Department of Biochemistry, Stanford University School of Medicine, Stanford, CA, USA
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49
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Smurova K, De Wulf P. Centromere and Pericentromere Transcription: Roles and Regulation … in Sickness and in Health. Front Genet 2018; 9:674. [PMID: 30627137 PMCID: PMC6309819 DOI: 10.3389/fgene.2018.00674] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/04/2018] [Indexed: 12/26/2022] Open
Abstract
The chromosomal loci known as centromeres (CEN) mediate the equal distribution of the duplicated genome between both daughter cells. Specifically, centromeres recruit a protein complex named the kinetochore, that bi-orients the replicated chromosome pairs to the mitotic or meiotic spindle structure. The paired chromosomes are then separated, and the individual chromosomes segregate in opposite direction along the regressing spindle into each daughter cell. Erroneous kinetochore assembly or activity produces aneuploid cells that contain an abnormal number of chromosomes. Aneuploidy may incite cell death, developmental defects (including genetic syndromes), and cancer (>90% of all cancer cells are aneuploid). While kinetochores and their activities have been preserved through evolution, the CEN DNA sequences have not. Hence, to be recognized as sites for kinetochore assembly, CEN display conserved structural themes. In addition, CEN nucleosomes enclose a CEN-exclusive variant of histone H3, named CENP-A, and carry distinct epigenetic labels on CENP-A and the other CEN histone proteins. Through the cell cycle, CEN are transcribed into non-coding RNAs. After subsequent processing, they become key components of the CEN chromatin by marking the CEN locus and by stably anchoring the CEN-binding kinetochore proteins. CEN transcription is tightly regulated, of low intensity, and essential for differentiation and development. Under- or overexpression of CEN transcripts, as documented for myriad cancers, provoke chromosome missegregation and aneuploidy. CEN are genetically stable and fully competent only when they are insulated from the surrounding, pericentromeric chromatin, which must be silenced. We will review CEN transcription and its contribution to faithful kinetochore function. We will further discuss how pericentromeric chromatin is silenced by RNA processing and transcriptionally repressive chromatin marks. We will report on the transcriptional misregulation of (peri)centromeres during stress, natural aging, and disease and reflect on whether their transcripts can serve as future diagnostic tools and anti-cancer targets in the clinic.
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Affiliation(s)
- Ksenia Smurova
- Centre for Integrative Biology, University of Trento, Trento, Italy
| | - Peter De Wulf
- Centre for Integrative Biology, University of Trento, Trento, Italy
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Liu C, Zhu R, Mao Y. Nuclear Actin Polymerized by mDia2 Confines Centromere Movement during CENP-A Loading. iScience 2018; 9:314-327. [PMID: 30448731 PMCID: PMC6240728 DOI: 10.1016/j.isci.2018.10.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 10/04/2018] [Accepted: 10/29/2018] [Indexed: 12/31/2022] Open
Abstract
Centromeres are specialized chromosomal regions epigenetically defined by the histone H3 variant centromere protein A (CENP-A). CENP-A needs to be replenished in every cell cycle, but how new CENP-A is stably incorporated into centromeric chromatin remains unclear. We have discovered that a cytoskeletal protein, diaphanous formin mDia2, is essential for the stable incorporation of new CENP-A proteins into centromeric nucleosomes. Here we report that mDia2-mediated formation of dynamic and short nuclear actin filaments in G1 nucleus is required to maintain CENP-A levels at the centromere. Importantly, mDia2 and nuclear actin are required for constrained centromere movement during CENP-A loading, and depleting nuclear actin or MgcRacGAP, which lies upstream of mDia2, extends centromeric association of the CENP-A loading chaperone Holliday junction recognition protein (HJURP). Our findings thus suggest that nuclear actin polymerized by mDia2 contributes to the physical confinement of G1 centromeres so that HJURP-mediated CENP-A loading reactions can be productive, and centromere's epigenetic identity can be stably maintained.
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Affiliation(s)
- Chenshu Liu
- Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, 630 W 168(th) Street, New York, NY 10032, USA.
| | - Ruijun Zhu
- Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, 630 W 168(th) Street, New York, NY 10032, USA
| | - Yinghui Mao
- Department of Pathology and Cell Biology, Columbia University Vagelos College of Physicians and Surgeons, 630 W 168(th) Street, New York, NY 10032, USA.
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