1
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Houston J, Vissotsky C, Deep A, Hakozaki H, Crews E, Oegema K, Corbett KD, Lara-Gonzalez P, Kim T, Desai A. Phospho-KNL-1 recognition by a TPR domain targets the BUB-1-BUB-3 complex to C. elegans kinetochores. J Cell Biol 2024; 223:e202402036. [PMID: 38578284 PMCID: PMC10996584 DOI: 10.1083/jcb.202402036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/21/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024] Open
Abstract
During mitosis, the Bub1-Bub3 complex concentrates at kinetochores, the microtubule-coupling interfaces on chromosomes, where it contributes to spindle checkpoint activation, kinetochore-spindle microtubule interactions, and protection of centromeric cohesion. Bub1 has a conserved N-terminal tetratricopeptide repeat (TPR) domain followed by a binding motif for its conserved interactor Bub3. The current model for Bub1-Bub3 localization to kinetochores is that Bub3, along with its bound motif from Bub1, recognizes phosphorylated "MELT" motifs in the kinetochore scaffold protein Knl1. Motivated by the greater phenotypic severity of BUB-1 versus BUB-3 loss in C. elegans, we show that the BUB-1 TPR domain directly recognizes a distinct class of phosphorylated motifs in KNL-1 and that this interaction is essential for BUB-1-BUB-3 localization and function. BUB-3 recognition of phospho-MELT motifs additively contributes to drive super-stoichiometric accumulation of BUB-1-BUB-3 on its KNL-1 scaffold during mitotic entry. Bub1's TPR domain interacts with Knl1 in other species, suggesting that collaboration of TPR-dependent and Bub3-dependent interfaces in Bub1-Bub3 localization and functions may be conserved.
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Affiliation(s)
- Jack Houston
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
| | | | - Amar Deep
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Hiroyuki Hakozaki
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
| | - Enice Crews
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Karen Oegema
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Kevin D. Corbett
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
- Department of Molecular Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Pablo Lara-Gonzalez
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA, USA
| | - Taekyung Kim
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
- Department of Biology Education, Pusan National University, Busan, Republic of Korea
| | - Arshad Desai
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA, USA
- Department of Cell and Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, CA, USA
- Ludwig Institute for Cancer Research, La Jolla, CA, USA
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
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2
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Ballmer D, Carter W, van Hooff JJE, Tromer EC, Ishii M, Ludzia P, Akiyoshi B. Kinetoplastid kinetochore proteins KKT14-KKT15 are divergent Bub1/BubR1-Bub3 proteins. Open Biol 2024; 14:240025. [PMID: 38862021 DOI: 10.1098/rsob.240025] [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: 01/31/2024] [Accepted: 03/12/2024] [Indexed: 06/13/2024] Open
Abstract
Faithful transmission of genetic material is crucial for the survival of all organisms. In many eukaryotes, a feedback control mechanism called the spindle checkpoint ensures chromosome segregation fidelity by delaying cell cycle progression until all chromosomes achieve proper attachment to the mitotic spindle. Kinetochores are the macromolecular complexes that act as the interface between chromosomes and spindle microtubules. While most eukaryotes have canonical kinetochore proteins that are widely conserved, kinetoplastids such as Trypanosoma brucei have a seemingly unique set of kinetochore proteins including KKT1-25. It remains poorly understood how kinetoplastids regulate cell cycle progression or ensure chromosome segregation fidelity. Here, we report a crystal structure of the C-terminal domain of KKT14 from Apiculatamorpha spiralis and uncover that it is a pseudokinase. Its structure is most similar to the kinase domain of a spindle checkpoint protein Bub1. In addition, KKT14 has a putative ABBA motif that is present in Bub1 and its paralogue BubR1. We also find that the N-terminal part of KKT14 interacts with KKT15, whose WD40 repeat beta-propeller is phylogenetically closely related to a direct interactor of Bub1/BubR1 called Bub3. Our findings indicate that KKT14-KKT15 are divergent orthologues of Bub1/BubR1-Bub3, which promote accurate chromosome segregation in trypanosomes.
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Affiliation(s)
- Daniel Ballmer
- Department of Biochemistry, University of Oxford , Oxford OX1 3QU, UK
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh , Edinburgh EH9 3BF, UK
| | - William Carter
- Department of Biochemistry, University of Oxford , Oxford OX1 3QU, UK
| | - Jolien J E van Hooff
- Laboratory of Microbiology, Department of Agrotechnology and Food Sciences, Wageningen University and Research , 6708 HB Wageningen, The Netherlands
| | - Eelco C Tromer
- Cell Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, Faculty of Science and Engineering, University of Groningen , 9747 AG Groningen, The Netherlands
| | - Midori Ishii
- Department of Biochemistry, University of Oxford , Oxford OX1 3QU, UK
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh , Edinburgh EH9 3BF, UK
| | - Patryk Ludzia
- Department of Biochemistry, University of Oxford , Oxford OX1 3QU, UK
| | - Bungo Akiyoshi
- Department of Biochemistry, University of Oxford , Oxford OX1 3QU, UK
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh , Edinburgh EH9 3BF, UK
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3
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Corno A, Cordeiro MH, Allan LA, Lim Q, Harrington E, Smith RJ, Saurin AT. A bifunctional kinase-phosphatase module balances mitotic checkpoint strength and kinetochore-microtubule attachment stability. EMBO J 2023; 42:e112630. [PMID: 37712330 PMCID: PMC10577578 DOI: 10.15252/embj.2022112630] [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: 09/16/2022] [Revised: 08/23/2023] [Accepted: 08/28/2023] [Indexed: 09/16/2023] Open
Abstract
Two major mechanisms safeguard genome stability during mitosis: the mitotic checkpoint delays mitosis until all chromosomes have attached to microtubules, and the kinetochore-microtubule error-correction pathway keeps this attachment process free from errors. We demonstrate here that the optimal strength and dynamics of these processes are set by a kinase-phosphatase pair (PLK1-PP2A) that engage in negative feedback from adjacent phospho-binding motifs on the BUB complex. Uncoupling this feedback to skew the balance towards PLK1 produces a strong checkpoint, hypostable microtubule attachments and mitotic delays. Conversely, skewing the balance towards PP2A causes a weak checkpoint, hyperstable microtubule attachments and chromosome segregation errors. These phenotypes are associated with altered BUB complex recruitment to KNL1-MELT motifs, implicating PLK1-PP2A in controlling auto-amplification of MELT phosphorylation. In support, KNL1-BUB disassembly becomes contingent on PLK1 inhibition when KNL1 is engineered to contain excess MELT motifs. This elevates BUB-PLK1/PP2A complex levels on metaphase kinetochores, stabilises kinetochore-microtubule attachments, induces chromosome segregation defects and prevents KNL1-BUB disassembly at anaphase. Together, these data demonstrate how a bifunctional PLK1/PP2A module has evolved together with the MELT motifs to optimise BUB complex dynamics and ensure accurate chromosome segregation.
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Affiliation(s)
- Andrea Corno
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Marilia H Cordeiro
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Lindsey A Allan
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Qian‐Wei Lim
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Elena Harrington
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Richard J Smith
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
| | - Adrian T Saurin
- Cellular and Systems Medicine, School of MedicineUniversity of DundeeDundeeUK
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4
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McAinsh AD, Kops GJPL. Principles and dynamics of spindle assembly checkpoint signalling. Nat Rev Mol Cell Biol 2023:10.1038/s41580-023-00593-z. [PMID: 36964313 DOI: 10.1038/s41580-023-00593-z] [Citation(s) in RCA: 45] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/22/2023] [Indexed: 03/26/2023]
Abstract
The transmission of a complete set of chromosomes to daughter cells during cell division is vital for development and tissue homeostasis. The spindle assembly checkpoint (SAC) ensures correct segregation by informing the cell cycle machinery of potential errors in the interactions of chromosomes with spindle microtubules prior to anaphase. To do so, the SAC monitors microtubule engagement by specialized structures known as kinetochores and integrates local mechanical and chemical cues such that it can signal in a sensitive, responsive and robust manner. In this Review, we discuss how SAC proteins interact to allow production of the mitotic checkpoint complex (MCC) that halts anaphase progression by inhibiting the anaphase-promoting complex/cyclosome (APC/C). We highlight recent advances aimed at understanding the dynamic signalling properties of the SAC and how it interprets various naturally occurring intermediate attachment states. Further, we discuss SAC signalling in the context of the mammalian multisite kinetochore and address the impact of the fibrous corona. We also identify current challenges in understanding how the SAC ensures high-fidelity chromosome segregation.
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Affiliation(s)
- Andrew D McAinsh
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK.
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
| | - Geert J P L Kops
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Centre Utrecht, Utrecht, The Netherlands.
- Oncode Institute, Utrecht, The Netherlands.
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5
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Vosseberg J, Stolker D, von der Dunk SHA, Snel B. Integrating Phylogenetics With Intron Positions Illuminates the Origin of the Complex Spliceosome. Mol Biol Evol 2023; 40:6985000. [PMID: 36631250 PMCID: PMC9887622 DOI: 10.1093/molbev/msad011] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 12/09/2022] [Accepted: 12/29/2022] [Indexed: 01/13/2023] Open
Abstract
Eukaryotic genes are characterized by the presence of introns that are removed from pre-mRNA by a spliceosome. This ribonucleoprotein complex is comprised of multiple RNA molecules and over a hundred proteins, which makes it one of the most complex molecular machines that originated during the prokaryote-to-eukaryote transition. Previous works have established that these introns and the spliceosomal core originated from self-splicing introns in prokaryotes. Yet, how the spliceosomal core expanded by recruiting many additional proteins remains largely elusive. In this study, we use phylogenetic analyses to infer the evolutionary history of 145 proteins that we could trace back to the spliceosome in the last eukaryotic common ancestor. We found that an overabundance of proteins derived from ribosome-related processes was added to the prokaryote-derived core. Extensive duplications of these proteins substantially increased the complexity of the emerging spliceosome. By comparing the intron positions between spliceosomal paralogs, we infer that most spliceosomal complexity postdates the spread of introns through the proto-eukaryotic genome. The reconstruction of early spliceosomal evolution provides insight into the driving forces behind the emergence of complexes with many proteins during eukaryogenesis.
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Affiliation(s)
- Julian Vosseberg
- Theoretical Biology and Bioinformatics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, the Netherlands,Laboratory of Microbiology, Wageningen University & Research, 6700 EH Wageningen, the Netherlands
| | - Daan Stolker
- Theoretical Biology and Bioinformatics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, the Netherlands
| | - Samuel H A von der Dunk
- Theoretical Biology and Bioinformatics, Department of Biology, Faculty of Science, Utrecht University, 3584 CH Utrecht, the Netherlands
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6
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Fischer ES. Kinetochore‐catalyzed MCC
formation: A structural perspective. IUBMB Life 2022; 75:289-310. [PMID: 36518060 DOI: 10.1002/iub.2697] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 11/08/2022] [Indexed: 12/23/2022]
Abstract
The spindle assembly checkpoint (SAC) is a cellular surveillance mechanism that functions to ensure accurate chromosome segregation during mitosis. Macromolecular complexes known as kinetochores, act as the interface of sister chromatid attachment to spindle microtubules. In response to unattached kinetochores, the SAC activates its effector, the mitotic checkpoint complex (MCC), which delays mitotic exit until all sister chromatid pairs have achieved successful attachment to the bipolar mitotic spindle. Formation of the MCC (composed of Mad2, BubR1, Bub3 and Cdc20) is regulated by an Mps1 kinase-dependent phosphorylation signaling cascade which assembles and repositions components of the MCC onto a catalytic scaffold. This scaffold functions to catalyze the conversion of the HORMA-domain protein Mad2 from an "inactive" open-state (O-Mad2) into an "active" closed-Mad2 (C-Mad2), and simultaneous Cdc20 binding. Here, our current understanding of the molecular mechanisms underlying the kinetic barrier to C-Mad2:Cdc20 formation will be reviewed. Recent progress in elucidating the precise molecular choreography orchestrated by the catalytic scaffold to rapidly assemble the MCC will be examined, and unresolved questions will be highlighted. Ultimately, understanding how the SAC rapidly activates the checkpoint not only provides insights into how cells maintain genomic integrity during mitosis, but also provides a paradigm for how cells can utilize molecular switches, including other HORMA domain-containing proteins, to make rapid changes to a cell's physiological state.
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Affiliation(s)
- Elyse S. Fischer
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus Cambridge UK
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7
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Banerjee A, Chen C, Humphrey L, Tyson JJ, Joglekar AP. BubR1 recruitment to the kinetochore via Bub1 enhances spindle assembly checkpoint signaling. Mol Biol Cell 2022; 33:br16. [PMID: 35767360 PMCID: PMC9582629 DOI: 10.1091/mbc.e22-03-0085] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 06/15/2022] [Accepted: 06/21/2022] [Indexed: 11/11/2022] Open
Abstract
During mitosis, unattached kinetochores in a dividing cell activate the spindle assembly checkpoint (SAC) and delay anaphase onset by generating the anaphase-inhibitory mitotic checkpoint complex (MCC). These kinetochores generate the MCC by recruiting its constituent proteins, including BubR1. In principle, BubR1 recruitment to signaling kinetochores should increase its local concentration and promote MCC formation. However, in human cells BubR1 is mainly thought to sensitize the SAC to silencing. Whether BubR1 localization to signaling kinetochores by itself enhances SAC signaling remains unknown. Therefore, we used ectopic SAC activation (eSAC) systems to isolate two molecules that recruit BubR1 to the kinetochore, the checkpoint protein Bub1 and the KI and MELT motifs in the kinetochore protein KNL1, and observed their contribution to eSAC signaling. Our quantitative analyses and mathematical modeling show that Bub1-mediated BubR1 recruitment to the human kinetochore promotes SAC signaling and highlight BubR1's dual role of strengthening the SAC directly and silencing it indirectly.
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Affiliation(s)
- Anand Banerjee
- Academy of Integrated Science, Virginia Polytechnic Institute & State University, Blacksburg, VA 24601
| | - Chu Chen
- Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Lauren Humphrey
- Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - John J. Tyson
- Department of Biological Sciences, Virginia Polytechnic Institute & State University, Blacksburg, VA 24601
| | - Ajit P. Joglekar
- Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109
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8
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Elowe S, Bolanos-Garcia VM. The spindle checkpoint proteins BUB1 and BUBR1: (SLiM)ming down to the basics. Trends Biochem Sci 2022; 47:352-366. [DOI: 10.1016/j.tibs.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 01/19/2022] [Accepted: 01/20/2022] [Indexed: 12/16/2022]
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9
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Roy B, Han SJY, Fontan AN, Jema S, Joglekar AP. Aurora B phosphorylates Bub1 to promote spindle assembly checkpoint signaling. Curr Biol 2022; 32:237-247.e6. [PMID: 34861183 PMCID: PMC8752509 DOI: 10.1016/j.cub.2021.10.049] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 08/24/2021] [Accepted: 10/22/2021] [Indexed: 01/12/2023]
Abstract
Accurate chromosome segregation during cell division requires amphitelic chromosome attachment to the spindle apparatus. It is ensured by the combined activity of the spindle assembly checkpoint (SAC),1 a signaling mechanism that delays anaphase onset in response to unattached chromosomes, and an error correction mechanism that eliminates syntelic attachments.2 The SAC becomes active when Mps1 kinase sequentially phosphorylates the kinetochore protein Spc105/KNL1 and the signaling proteins that Spc105/KNL1 recruits to facilitate the production of the mitotic checkpoint complex (MCC).3-8 The error correction mechanism is regulated by the Aurora B kinase, but Aurora B also promotes SAC signaling via indirect mechanisms.9-12 Here we present evidence that Aurora B kinase activity directly promotes MCC production by working downstream of Mps1 in budding yeast and human cells. Using the ectopic SAC activation (eSAC) system, we find that the conditional dimerization of Aurora B in budding yeast and an Aurora B recruitment domain in HeLa cells with either Bub1 or Mad1, but not the phosphodomain of Spc105/KNL1, leads to ectopic MCC production and mitotic arrest.13-16 Importantly, Bub1 must recruit both Mad1 and Cdc20 for this ectopic signaling activity. These and other data show that Aurora B cooperates with Bub1 to promote MCC production, but only after Mps1 licenses Bub1 recruitment to the kinetochore. This direct involvement of Aurora B in SAC signaling may maintain SAC signaling even after Mps1 activity in the kinetochore is lowered.
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Affiliation(s)
- Babhrubahan Roy
- Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Pl., Ann Arbor, MI-48109, USA
| | - Simon J. Y. Han
- Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Pl., Ann Arbor, MI-48109, USA,present address: Medical Scientist Training Program, University of Cincinnati College of Medicine, 3230 Eden Ave, Cincinnati, OH 45267, USA
| | - Adrienne N. Fontan
- Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Pl., Ann Arbor, MI-48109, USA,present address: Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, 455 Main St, Cambridge, MA 02142
| | - Soubhagyalaxmi Jema
- Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Pl., Ann Arbor, MI-48109, USA
| | - Ajit P. Joglekar
- Cell & Developmental Biology, University of Michigan Medical School, 109 Zina Pitcher Pl., Ann Arbor, MI-48109, USA,corresponding author, lead contact: , Twitter handle: @AjitJoglekar1
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10
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Bolanos-Garcia VM. On the Regulation of Mitosis by the Kinetochore, a Macromolecular Complex and Organising Hub of Eukaryotic Organisms. Subcell Biochem 2022; 99:235-267. [PMID: 36151378 DOI: 10.1007/978-3-031-00793-4_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
The kinetochore is the multiprotein complex of eukaryotic organisms that is assembled on mitotic or meiotic centromeres to connect centromeric DNA with microtubules. Its function involves the coordinated action of more than 100 different proteins. The kinetochore acts as an organiser hub that establishes physical connections with microtubules and centromere-associated proteins and recruits central protein components of the spindle assembly checkpoint (SAC), an evolutionarily conserved surveillance mechanism of eukaryotic organisms that detects unattached kinetochores and destabilises incorrect kinetochore-microtubule attachments. The molecular communication between the kinetochore and the SAC is highly dynamic and tightly regulated to ensure that cells can progress towards anaphase until each chromosome is properly bi-oriented on the mitotic spindle. This is achieved through an interplay of highly cooperative interactions and concerted phosphorylation/dephosphorylation events that are organised in time and space.This contribution discusses our current understanding of the function, structure and regulation of the kinetochore, in particular, how its communication with the SAC results in the amplification of specific signals to exquisitely control the eukaryotic cell cycle. This contribution also addresses recent advances in machine learning approaches, cell imaging and proteomics techniques that have enhanced our understanding of the molecular mechanisms that ensure the high fidelity and timely segregation of the genetic material every time a cell divides as well as the current challenges in the study of this fascinating molecular machine.
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Affiliation(s)
- Victor M Bolanos-Garcia
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK.
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11
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Salas-Leiva DE, Tromer EC, Curtis BA, Jerlström-Hultqvist J, Kolisko M, Yi Z, Salas-Leiva JS, Gallot-Lavallée L, Williams SK, Kops GJPL, Archibald JM, Simpson AGB, Roger AJ. Genomic analysis finds no evidence of canonical eukaryotic DNA processing complexes in a free-living protist. Nat Commun 2021; 12:6003. [PMID: 34650064 PMCID: PMC8516963 DOI: 10.1038/s41467-021-26077-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 09/14/2021] [Indexed: 12/14/2022] Open
Abstract
Cells replicate and segregate their DNA with precision. Previous studies showed that these regulated cell-cycle processes were present in the last eukaryotic common ancestor and that their core molecular parts are conserved across eukaryotes. However, some metamonad parasites have secondarily lost components of the DNA processing and segregation apparatuses. To clarify the evolutionary history of these systems in these unusual eukaryotes, we generated a genome assembly for the free-living metamonad Carpediemonas membranifera and carried out a comparative genomics analysis. Here, we show that parasitic and free-living metamonads harbor an incomplete set of proteins for processing and segregating DNA. Unexpectedly, Carpediemonas species are further streamlined, lacking the origin recognition complex, Cdc6 and most structural kinetochore subunits. Carpediemonas species are thus the first known eukaryotes that appear to lack this suite of conserved complexes, suggesting that they likely rely on yet-to-be-discovered or alternative mechanisms to carry out these fundamental processes.
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Affiliation(s)
- Dayana E. Salas-Leiva
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada ,grid.5335.00000000121885934Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Eelco C. Tromer
- grid.5335.00000000121885934Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom ,grid.4830.f0000 0004 0407 1981Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Groningen, Netherlands
| | - Bruce A. Curtis
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Jon Jerlström-Hultqvist
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Martin Kolisko
- grid.418095.10000 0001 1015 3316Institute of Parasitology, Biology Centre, Czech Acad. Sci, České Budějovice, Czech Republic
| | - Zhenzhen Yi
- grid.263785.d0000 0004 0368 7397Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Science, South China Normal University, Guangzhou, 510631 China
| | - Joan S. Salas-Leiva
- grid.466575.30000 0001 1835 194XCONACyT-Centro de Investigación en Materiales Avanzados, Departamento de medio ambiente y energía, Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31136 Chihuahua, Chih. México
| | - Lucie Gallot-Lavallée
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Shelby K. Williams
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Geert J. P. L. Kops
- grid.7692.a0000000090126352Oncode Institute, Hubrecht Institute – KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Centre Utrecht, Utrecht, The Netherlands
| | - John M. Archibald
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Alastair G. B. Simpson
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
| | - Andrew J. Roger
- grid.55602.340000 0004 1936 8200Institute for Comparative Genomics (ICG), Department of Biochemistry and Molecular Biology, Dalhousie University, Halifax, NS B3H 4R2 Canada
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12
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Kops GJPL, Snel B, Tromer EC. Evolutionary Dynamics of the Spindle Assembly Checkpoint in Eukaryotes. Curr Biol 2021; 30:R589-R602. [PMID: 32428500 DOI: 10.1016/j.cub.2020.02.021] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The tremendous diversity in eukaryotic life forms can ultimately be traced back to evolutionary modifications at the level of molecular networks. Deep understanding of these modifications will not only explain cellular diversity, but will also uncover different ways to execute similar processes and expose the evolutionary 'rules' that shape the molecular networks. Here, we review the evolutionary dynamics of the spindle assembly checkpoint (SAC), a signaling network that guards fidelity of chromosome segregation. We illustrate how the interpretation of divergent SAC systems in eukaryotic species is facilitated by combining detailed molecular knowledge of the SAC and extensive comparative genome analyses. Ultimately, expanding this to other core cellular systems and experimentally interrogating such systems in organisms from all major lineages may start outlining the routes to and eventual manifestation of the cellular diversity of eukaryotic life.
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Affiliation(s)
- Geert J P L Kops
- Oncode Institute, Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Centre Utrecht, Utrecht, The Netherlands.
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Department of Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands.
| | - Eelco C Tromer
- Department of Biochemistry, University of Cambridge, Cambridge, UK.
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13
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Elowe S. Adventures of the undead at kinetochores. Mol Cell Oncol 2021; 8:1876511. [PMID: 33860079 DOI: 10.1080/23723556.2021.1876511] [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: 10/22/2022]
Abstract
At the metaphase-to-anaphase transition, phosphatase activity feeds back to reverse early mitotic phosphorylation events. Our recent work indicates that the pseudokinase domain of the spindle checkpoint protein BUB1 (Budding Uninhibited by Benzimidazoles 1) mitotic checkpoint serine/threonine kinase B (BUB1B, BUBR1) maintains kinase-phosphatase balance at the outer kinetochore during mitotic exit.
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Affiliation(s)
- Sabine Elowe
- Axe de reproduction, santé de la mère et de l'enfant, Centre de recherche du Centre Hospitalier Universitaire (CHU) de Québec-Université Laval, Québec, QC, Canada.,PROTEO-regroupement québécois de recherche sur la fonction, l'ingénierie et les applications des protéines, Québec, QC, Canada.,Département de Pédiatrie, Faculté de Médicine, Université Laval et le Centre de recherche sur le cancer de l'Université Laval, Québec, QC, Canada
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14
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Cordeiro MH, Smith RJ, Saurin AT. Kinetochore phosphatases suppress autonomous Polo-like kinase 1 activity to control the mitotic checkpoint. J Cell Biol 2020; 219:e202002020. [PMID: 33125045 PMCID: PMC7608062 DOI: 10.1083/jcb.202002020] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 08/20/2020] [Accepted: 10/12/2020] [Indexed: 01/04/2023] Open
Abstract
Local phosphatase regulation is needed at kinetochores to silence the mitotic checkpoint (a.k.a. spindle assembly checkpoint [SAC]). A key event in this regard is the dephosphorylation of MELT repeats on KNL1, which removes SAC proteins from the kinetochore, including the BUB complex. We show here that PP1 and PP2A-B56 phosphatases are primarily required to remove Polo-like kinase 1 (PLK1) from the BUB complex, which can otherwise maintain MELT phosphorylation in an autocatalytic manner. This appears to be their principal role in the SAC because both phosphatases become redundant if PLK1 is inhibited or BUB-PLK1 interaction is prevented. Surprisingly, MELT dephosphorylation can occur normally under these conditions even when the levels or activities of PP1 and PP2A are strongly inhibited at kinetochores. Therefore, these data imply that kinetochore phosphatase regulation is critical for the SAC, but primarily to restrain and extinguish autonomous PLK1 activity. This is likely a conserved feature of the metazoan SAC, since the relevant PLK1 and PP2A-B56 binding motifs have coevolved in the same region on MADBUB homologues.
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Affiliation(s)
| | | | - Adrian T. Saurin
- Division of Cellular Medicine, School of Medicine, University of Dundee, Dundee, UK
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15
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BUBR1 Pseudokinase Domain Promotes Kinetochore PP2A-B56 Recruitment, Spindle Checkpoint Silencing, and Chromosome Alignment. Cell Rep 2020; 33:108397. [PMID: 33207204 DOI: 10.1016/j.celrep.2020.108397] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 10/13/2020] [Accepted: 10/26/2020] [Indexed: 12/13/2022] Open
Abstract
The balance of phospho-signaling at the outer kinetochore is critical for forming accurate attachments between kinetochores and the mitotic spindle and timely exit from mitosis. A major player in determining this balance is the PP2A-B56 phosphatase, which is recruited to the kinase attachment regulatory domain (KARD) of budding uninhibited by benzimidazole 1-related 1 (BUBR1) in a phospho-dependent manner. This unleashes a rapid, switch-like phosphatase relay that reverses mitotic phosphorylation at the kinetochore, extinguishing the checkpoint and promoting anaphase. Here, we demonstrate that the C-terminal pseudokinase domain of human BUBR1 is required to promote KARD phosphorylation. Mutation or removal of the pseudokinase domain results in decreased PP2A-B56 recruitment to the outer kinetochore attenuated checkpoint silencing and errors in chromosome alignment as a result of imbalance in Aurora B activity. Our data, therefore, elucidate a function for the BUBR1 pseudokinase domain in ensuring accurate and timely exit from mitosis.
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16
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Recurrent sequence evolution after independent gene duplication. BMC Evol Biol 2020; 20:98. [PMID: 32770961 PMCID: PMC7414715 DOI: 10.1186/s12862-020-01660-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 07/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background Convergent and parallel evolution provide unique insights into the mechanisms of natural selection. Some of the most striking convergent and parallel (collectively recurrent) amino acid substitutions in proteins are adaptive, but there are also many that are selectively neutral. Accordingly, genome-wide assessment has shown that recurrent sequence evolution in orthologs is chiefly explained by nearly neutral evolution. For paralogs, more frequent functional change is expected because additional copies are generally not retained if they do not acquire their own niche. Yet, it is unknown to what extent recurrent sequence differentiation is discernible after independent gene duplications in different eukaryotic taxa. Results We develop a framework that detects patterns of recurrent sequence evolution in duplicated genes. This is used to analyze the genomes of 90 diverse eukaryotes. We find a remarkable number of families with a potentially predictable functional differentiation following gene duplication. In some protein families, more than ten independent duplications show a similar sequence-level differentiation between paralogs. Based on further analysis, the sequence divergence is found to be generally asymmetric. Moreover, about 6% of the recurrent sequence evolution between paralog pairs can be attributed to recurrent differentiation of subcellular localization. Finally, we reveal the specific recurrent patterns for the gene families Hint1/Hint2, Sco1/Sco2 and vma11/vma3. Conclusions The presented methodology provides a means to study the biochemical underpinning of functional differentiation between paralogs. For instance, two abundantly repeated substitutions are identified between independently derived Sco1 and Sco2 paralogs. Such identified substitutions allow direct experimental testing of the biological role of these residues for the repeated functional differentiation. We also uncover a diverse set of families with recurrent sequence evolution and reveal trends in the functional and evolutionary trajectories of this hitherto understudied phenomenon.
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17
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Tang R, Jiang Z, Chen F, Yu W, Fan K, Tan J, Zhang Z, Liu X, Li P, Yuan K. The Kinase Activity of Drosophila BubR1 Is Required for Insulin Signaling-Dependent Stem Cell Maintenance. Cell Rep 2020; 31:107794. [PMID: 32579921 DOI: 10.1016/j.celrep.2020.107794] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 04/29/2020] [Accepted: 05/31/2020] [Indexed: 02/06/2023] Open
Abstract
As a core component of the mitotic checkpoint complex, BubR1 has a modular organization of molecular functions, with KEN box and other motifs at the N terminus inhibiting the anaphase-promoting complex/cyclosome, and a kinase domain at the C terminus, whose function remains unsettled, especially at organismal levels. We generate knock-in BubR1 mutations in the Drosophila genome to separately disrupt the KEN box and the kinase domain. All of the mutants are homozygously viable and fertile and show no defects in mitotic progression. The mutants without kinase activity have an increased lifespan and phenotypic changes associated with attenuated insulin signaling, including reduced InR on the cell membrane, weakened PI3K and AKT activity, and elevated expression of dFoxO targets. The BubR1 kinase-dead mutants have a reduced cap cell number in female germaria, which can be rescued by expressing a constitutively active InR. We conclude that one major physiological role of BubR1 kinase in Drosophila is to modulate insulin signaling.
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Affiliation(s)
- Ruijun Tang
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Zhenghui Jiang
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Fang Chen
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Weiyu Yu
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Kaijing Fan
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Jieqiong Tan
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Zhuohua Zhang
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China
| | - Xing Liu
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, University of Science and Technology of China, Hefei 230027, China.
| | - Pishun Li
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - Kai Yuan
- Hunan Key Laboratory of Molecular Precision Medicine, Department of Neurosurgery, Xiangya Hospital, and Hunan Key Laboratory of Medical Genetics, School of Life Sciences, Central South University, Changsha, Hunan 410008, China; Center for Clinical Biorepositories and Biospecimens, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China; National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China.
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18
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Alfieri C, Tischer T, Barford D. A unique binding mode of Nek2A to the APC/C allows its ubiquitination during prometaphase. EMBO Rep 2020; 21:e49831. [PMID: 32307883 PMCID: PMC7271329 DOI: 10.15252/embr.201949831] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Revised: 03/11/2020] [Accepted: 03/17/2020] [Indexed: 11/09/2022] Open
Abstract
The anaphase-promoting complex (APC/C) is the key E3 ubiquitin ligase which directs mitotic progression and exit by catalysing the sequential ubiquitination of specific substrates. The activity of the APC/C in mitosis is restrained by the spindle assembly checkpoint (SAC), which coordinates chromosome segregation with the assembly of the mitotic spindle. The SAC effector is the mitotic checkpoint complex (MCC), which binds and inhibits the APC/C. It is incompletely understood how the APC/C switches substrate specificity in a cell cycle-specific manner. For instance, it is unclear how in prometaphase, when APC/C activity towards cyclin B and securin is repressed by the MCC, the kinase Nek2A is ubiquitinated. Here, we combine biochemical and structural analysis with functional studies in cells to show that Nek2A is a conformational-specific binder of the APC/C-MCC complex (APC/CMCC ) and that, in contrast to cyclin A, Nek2A can be ubiquitinated efficiently by the APC/C in conjunction with both the E2 enzymes UbcH10 and UbcH5. We propose that these special features of Nek2A allow its prometaphase-specific ubiquitination.
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Affiliation(s)
- Claudio Alfieri
- MRC Laboratory of Molecular BiologyCambridgeUK
- Present address:
Institute of Cancer ResearchLondonUK
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19
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Kops GJPL, Gassmann R. Crowning the Kinetochore: The Fibrous Corona in Chromosome Segregation. Trends Cell Biol 2020; 30:653-667. [PMID: 32386879 DOI: 10.1016/j.tcb.2020.04.006] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/08/2020] [Accepted: 04/08/2020] [Indexed: 01/30/2023]
Abstract
The kinetochore is at the heart of chromosome segregation in mitosis and meiosis. Rather than a static linker complex for chromatin and spindle microtubules, it is highly dynamic in composition, size, and shape. While known for decades that it can expand and grow a fibrous meshwork known as the corona, it was until recently unclear what constitutes this 'crown' and what its relevance is for kinetochore function. Here, we highlight recent discoveries in fibrous corona biology, and place them in the context of the processes that orchestrate high-fidelity chromosome segregation.
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Affiliation(s)
- Geert J P L Kops
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Centre Utrecht, Utrecht, 3584, CT, The Netherlands.
| | - Reto Gassmann
- Instituto de Biologia Molecular e Celular (IBMC), Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, 4200-135 Porto, Portugal.
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20
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van Hooff JJE, Tromer E, van Dam TJP, Kops GJPL, Snel B. Inferring the Evolutionary History of Your Favorite Protein: A Guide for Molecular Biologists. Bioessays 2020; 41:e1900006. [PMID: 31026339 DOI: 10.1002/bies.201900006] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/17/2019] [Indexed: 01/01/2023]
Abstract
Comparative genomics has proven a fruitful approach to acquire many functional and evolutionary insights into core cellular processes. Here it is argued that in order to perform accurate and interesting comparative genomics, one first and foremost has to be able to recognize, postulate, and revise different evolutionary scenarios. After all, these studies lack a simple protocol, due to different proteins having different evolutionary dynamics and demanding different approaches. The authors here discuss this challenge from a practical (what are the observations?) and conceptual (how do these indicate a specific evolutionary scenario?) viewpoint, with the aim to guide investigators who want to analyze the evolution of their protein(s) of interest. By sharing how the authors draft, test, and update such a scenario and how it directs their investigations, the authors hope to illuminate how to execute molecular evolution studies and how to interpret them. Also see the video abstract here https://youtu.be/VCt3l2pbdbQ.
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Affiliation(s)
- Jolien J E van Hooff
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.,Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands
| | - Eelco Tromer
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.,Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands.,Department of Biochemistry, University of Cambridge, Hopkins Building, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Teunis J P van Dam
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Geert J P L Kops
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Uppsalalaan 8, 3584 CT, Utrecht, The Netherlands.,Molecular Cancer Research, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX, Utrecht, The Netherlands
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
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21
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Leontiou I, London N, May KM, Ma Y, Grzesiak L, Medina-Pritchard B, Amin P, Jeyaprakash AA, Biggins S, Hardwick KG. The Bub1-TPR Domain Interacts Directly with Mad3 to Generate Robust Spindle Checkpoint Arrest. Curr Biol 2019; 29:2407-2414.e7. [PMID: 31257143 PMCID: PMC6657678 DOI: 10.1016/j.cub.2019.06.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 01/30/2019] [Accepted: 06/04/2019] [Indexed: 12/14/2022]
Abstract
The spindle checkpoint monitors kinetochore-microtubule interactions and generates a “wait anaphase” delay when any defects are apparent [1, 2, 3]. This provides time for cells to correct chromosome attachment errors and ensure high-fidelity chromosome segregation. Checkpoint signals are generated at unattached chromosomes during mitosis. To activate the checkpoint, Mps1Mph1 kinase phosphorylates the kinetochore component KNL1Spc105/Spc7 on conserved MELT motifs to recruit Bub3-Bub1 complexes [4, 5, 6] via a direct Bub3 interaction with phospho-MELT motifs [7, 8]. Mps1Mph1 then phosphorylates Bub1, which strengthens its interaction with Mad1-Mad2 complexes to produce a signaling platform [9, 10]. The Bub1-Mad1 platform is thought to recruit Mad3, Cdc20, and Mad2 to produce the mitotic checkpoint complex (MCC), which is the diffusible wait anaphase signal [9, 11, 12]. The MCC binds and inhibits the mitotic E3 ubiquitin ligase, known as Cdc20-anaphase promoting complex/cyclosome (APC/C), and stabilizes securin and cyclin to delay anaphase onset [13, 14, 15, 16, 17]. Here we demonstrate, in both budding and fission yeast, that kinetochores and KNL1Spc105/Spc7 can be bypassed; simply inducing heterodimers of Mps1Mph1 kinase and Bub1 is sufficient to trigger metaphase arrest that is dependent on Mad1, Mad2, and Mad3. We use this to dissect the domains of Bub1 necessary for arrest, highlighting the need for Bub1-CD1, which binds Mad1 [9], and Bub1’s highly conserved N-terminal tetratricopeptide repeat (TPR) domain [18, 19]. We demonstrate that the Bub1 TPR domain is both necessary and sufficient to bind and recruit Mad3. We propose that this brings Mad3 into close proximity to Mad1-Mad2 and Mps1Mph1 kinase, enabling efficient generation of MCC complexes. Heterodimers of Mps1 and Bub1 generate robust spindle checkpoint arrest in yeasts This arrest is independent of kinetochores but requires Bub1-CD1 and the Bub1-TPR The Bub1-TPR is both necessary and sufficient for Mad3 interaction and recruitment Recombinant fission yeast Bub1-TPR and Mad3 form a stable complex
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Affiliation(s)
- Ioanna Leontiou
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Nitobe London
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Karen M May
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Yingrui Ma
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Lucile Grzesiak
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Bethan Medina-Pritchard
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Priya Amin
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - A Arockia Jeyaprakash
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Kevin G Hardwick
- Institute of Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK.
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22
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Plowman R, Singh N, Tromer EC, Payan A, Duro E, Spanos C, Rappsilber J, Snel B, Kops GJPL, Corbett KD, Marston AL. The molecular basis of monopolin recruitment to the kinetochore. Chromosoma 2019; 128:331-354. [PMID: 31037469 PMCID: PMC6823300 DOI: 10.1007/s00412-019-00700-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 03/08/2019] [Accepted: 03/19/2019] [Indexed: 11/29/2022]
Abstract
The monopolin complex is a multifunctional molecular crosslinker, which in S. pombe binds and organises mitotic kinetochores to prevent aberrant kinetochore-microtubule interactions. In the budding yeast S. cerevisiae, whose kinetochores bind a single microtubule, the monopolin complex crosslinks and mono-orients sister kinetochores in meiosis I, enabling the biorientation and segregation of homologs. Here, we show that both the monopolin complex subunit Csm1 and its binding site on the kinetochore protein Dsn1 are broadly distributed throughout eukaryotes, suggesting a conserved role in kinetochore organisation and function. We find that budding yeast Csm1 binds two conserved motifs in Dsn1, one (termed Box 1) representing the ancestral, widely conserved monopolin binding motif and a second (termed Box 2-3) with a likely role in enforcing specificity of sister kinetochore crosslinking. We find that Box 1 and Box 2-3 bind the same conserved hydrophobic cavity on Csm1, suggesting competition or handoff between these motifs. Using structure-based mutants, we also find that both Box 1 and Box 2-3 are critical for monopolin function in meiosis. We identify two conserved serine residues in Box 2-3 that are phosphorylated in meiosis and whose mutation to aspartate stabilises Csm1-Dsn1 binding, suggesting that regulated phosphorylation of these residues may play a role in sister kinetochore crosslinking specificity. Overall, our results reveal the monopolin complex as a broadly conserved kinetochore organiser in eukaryotes, which budding yeast have co-opted to mediate sister kinetochore crosslinking through the addition of a second, regulatable monopolin binding interface.
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Affiliation(s)
- Rebecca Plowman
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Namit Singh
- Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, CA, 92093, USA.,Synthorx Inc., 11099 North Torrey Pines Road, Suite 290, La Jolla, CA, 92037, USA
| | - Eelco C Tromer
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands.,Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,University Medical Centre Utrecht, Utrecht, The Netherlands.,Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Angel Payan
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, 92093, USA.,Department of Chemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Eris Duro
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Christos Spanos
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK.,Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands
| | - Geert J P L Kops
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Kevin D Corbett
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, 92093, USA. .,Department of Chemistry, University of California, San Diego, La Jolla, CA, 92093, USA.
| | - Adele L Marston
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK.
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23
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Gross F, Bonaiuti P, Hauf S, Ciliberto A. Implications of alternative routes to APC/C inhibition by the mitotic checkpoint complex. PLoS Comput Biol 2018; 14:e1006449. [PMID: 30199529 PMCID: PMC6157902 DOI: 10.1371/journal.pcbi.1006449] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 09/26/2018] [Accepted: 08/20/2018] [Indexed: 01/19/2023] Open
Abstract
The mitotic checkpoint (also called spindle assembly checkpoint) is a signaling pathway that ensures faithful chromosome segregation. Mitotic checkpoint proteins inhibit the anaphase-promoting complex (APC/C) and its activator Cdc20 to prevent precocious anaphase. Checkpoint signaling leads to a complex of APC/C, Cdc20, and checkpoint proteins, in which the APC/C is inactive. In principle, this final product of the mitotic checkpoint can be obtained via different pathways, whose relevance still needs to be fully ascertained experimentally. Here, we use mathematical models to compare the implications on checkpoint response of the possible pathways leading to APC/C inhibition. We identify a previously unrecognized funneling effect for Cdc20, which favors Cdc20 incorporation into the inhibitory complex and therefore promotes checkpoint activity. Furthermore, we find that the presence or absence of one specific assembly reaction determines whether the checkpoint remains functional at elevated levels of Cdc20, which can occur in cancer cells. Our results reveal the inhibitory logics behind checkpoint activity, predict checkpoint efficiency in perturbed situations, and could inform molecular strategies to treat malignancies that exhibit Cdc20 overexpression. Cell division is a fundamental event in the life of cells. It requires that a mother cell gives rise to two daughters which carry the same genetic material of their mother. Thus, during each cell cycle the genetic material needs to be replicated, compacted into chromosomes and redistributed to the two daughter cells. Any mistake in chromosome segregation would attribute the wrong number of chromosomes to the progeny. Hence, the process of chromosome segregation is closely watched by a surveillance mechanism known as the mitotic checkpoint. The molecular players of the checkpoint pathway are well known: we know both the input (ie, the species to be inhibited and their inhibitors), and the output (ie, the inhibited species). However, we do not exactly know the path that leads from the former to the latter. In this manuscript, we use a mathematical approach to explore the properties of plausible mitotic checkpoint networks. We find that seemingly similar circuits show very different behaviors for high levels of the protein targeted by the mitotic checkpoint, Cdc20. Interestingly, this protein is often overexpressed in cancer cells. For physiological levels of Cdc20, instead, all the models we have analyzed are capable to mount an efficient response. We find that this is due to a series of consecutive protein-protein binding reactions that funnel Cdc20 towards its inhibited state. We call this the funneling effect. Our analysis helps understanding the inhibitory logics underlying the checkpoint, and proposes new concepts that could be applied to other inhibitory pathways.
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Affiliation(s)
- Fridolin Gross
- Istituto Firc di Oncologia Molecolare, IFOM, Milano, Italy
| | - Paolo Bonaiuti
- Istituto Firc di Oncologia Molecolare, IFOM, Milano, Italy
| | - Silke Hauf
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States of America
- Biocomplexity Institute, Virginia Tech, Blacksburg, VA, United States of America
- Center for Soft Matter and Biological Physics, Virginia Tech, Blacksburg, VA, United States of America
- * E-mail: (SH); (AC)
| | - Andrea Ciliberto
- Istituto Firc di Oncologia Molecolare, IFOM, Milano, Italy
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Pavia, Italy
- * E-mail: (SH); (AC)
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Oliferenko S. Understanding eukaryotic chromosome segregation from a comparative biology perspective. J Cell Sci 2018; 131:131/14/jcs203653. [PMID: 30030298 DOI: 10.1242/jcs.203653] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A long-appreciated variation in fundamental cell biological processes between different species is becoming increasingly tractable due to recent breakthroughs in whole-genome analyses and genome editing techniques. However, the bulk of our mechanistic understanding in cell biology continues to come from just a few well-established models. In this Review, I use the highly diverse strategies of chromosome segregation in eukaryotes as an instrument for a more general discussion on phenotypic variation, possible rules underlying its emergence and its utility in understanding conserved functional relationships underlying this process. Such a comparative approach, supported by modern molecular biology tools, might provide a wider, holistic view of biology that is difficult to achieve when concentrating on a single experimental system.
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Affiliation(s)
- Snezhana Oliferenko
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK .,Randall Centre for Cell and Molecular Biophysics, New Hunt's House, Guy's Campus, King's College London, London, SE1 1UL, UK
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25
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Sacristan C, Ahmad MUD, Keller J, Fermie J, Groenewold V, Tromer E, Fish A, Melero R, Carazo JM, Klumperman J, Musacchio A, Perrakis A, Kops GJ. Dynamic kinetochore size regulation promotes microtubule capture and chromosome biorientation in mitosis. Nat Cell Biol 2018; 20:800-810. [PMID: 29915359 PMCID: PMC6485389 DOI: 10.1038/s41556-018-0130-3] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/22/2018] [Indexed: 01/28/2023]
Abstract
Faithful chromosome segregation depends on the ability of sister kinetochores to attach to spindle microtubules. The outer layer of kinetochores transiently expands in early mitosis to form a fibrous corona, and compacts following microtubule capture. Here we show that the dynein adaptor Spindly and the RZZ (ROD-Zwilch-ZW10) complex drive kinetochore expansion in a dynein-independent manner. C-terminal farnesylation and MPS1 kinase activity cause conformational changes of Spindly that promote oligomerization of RZZ-Spindly complexes into a filamentous meshwork in cells and in vitro. Concurrent with kinetochore expansion, Spindly potentiates kinetochore compaction by recruiting dynein via three conserved short linear motifs. Expanded kinetochores unable to compact engage in extensive, long-lived lateral microtubule interactions that persist to metaphase, and result in merotelic attachments and chromosome segregation errors in anaphase. Thus, dynamic kinetochore size regulation in mitosis is coordinated by a single, Spindly-based mechanism that promotes initial microtubule capture and subsequent correct maturation of attachments.
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Affiliation(s)
- Carlos Sacristan
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Misbha Ud Din Ahmad
- Department of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Jenny Keller
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Job Fermie
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Vincent Groenewold
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Eelco Tromer
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Alexander Fish
- Department of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Roberto Melero
- Biocomputing Unit, National Center for Biotechnology (CSIC), Darwin 3, Campus Universidad Autónoma, Madrid, Spain
| | - José María Carazo
- Biocomputing Unit, National Center for Biotechnology (CSIC), Darwin 3, Campus Universidad Autónoma, Madrid, Spain
| | - Judith Klumperman
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
- Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstraße, Essen, Germany
| | - Anastassis Perrakis
- Department of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Geert Jpl Kops
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands.
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26
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Alfieri C, Zhang S, Barford D. Visualizing the complex functions and mechanisms of the anaphase promoting complex/cyclosome (APC/C). Open Biol 2017; 7:170204. [PMID: 29167309 PMCID: PMC5717348 DOI: 10.1098/rsob.170204] [Citation(s) in RCA: 106] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 10/10/2017] [Indexed: 12/17/2022] Open
Abstract
The anaphase promoting complex or cyclosome (APC/C) is a large multi-subunit E3 ubiquitin ligase that orchestrates cell cycle progression by mediating the degradation of important cell cycle regulators. During the two decades since its discovery, much has been learnt concerning its role in recognizing and ubiquitinating specific proteins in a cell-cycle-dependent manner, the mechanisms governing substrate specificity, the catalytic process of assembling polyubiquitin chains on its target proteins, and its regulation by phosphorylation and the spindle assembly checkpoint. The past few years have witnessed significant progress in understanding the quantitative mechanisms underlying these varied APC/C functions. This review integrates the overall functions and properties of the APC/C with mechanistic insights gained from recent cryo-electron microscopy (cryo-EM) studies of reconstituted human APC/C complexes.
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Affiliation(s)
- Claudio Alfieri
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Suyang Zhang
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - David Barford
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
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27
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Komaki S, Schnittger A. The Spindle Assembly Checkpoint in Arabidopsis Is Rapidly Shut Off during Severe Stress. Dev Cell 2017; 43:172-185.e5. [PMID: 29065308 DOI: 10.1016/j.devcel.2017.09.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Revised: 07/18/2017] [Accepted: 09/21/2017] [Indexed: 12/24/2022]
Abstract
The spindle assembly checkpoint (SAC) in animals and yeast assures equal segregation of chromosomes during cell division. The prevalent occurrence of polyploidy in flowering plants together with the observation that many plants can be readily forced to double their genomes by application of microtubule drugs raises the question of whether plants have a proper SAC. Here, we provide a functional framework of the core SAC proteins in Arabidopsis. We reveal that Arabidopsis will delay mitosis in a SAC-dependent manner if the spindle is perturbed. However, we also show that the molecular architecture of the SAC is unique in plants. Moreover, the SAC is short-lived and cannot stay active for more than 2 hr, after which the cell cycle is reset. This resetting opens the possibility for genome duplications and raises the hypothesis that a rapid termination of a SAC-induced mitotic arrest provides an adaptive advantage for plants impacting plant genome evolution.
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Affiliation(s)
- Shinichiro Komaki
- University of Hamburg, Biozentrum Klein Flottbek, Department of Developmental Biology, Ohnhorststrasse 18, D-22609 Hamburg, Germany
| | - Arp Schnittger
- University of Hamburg, Biozentrum Klein Flottbek, Department of Developmental Biology, Ohnhorststrasse 18, D-22609 Hamburg, Germany.
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28
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Overlack K, Bange T, Weissmann F, Faesen AC, Maffini S, Primorac I, Müller F, Peters JM, Musacchio A. BubR1 Promotes Bub3-Dependent APC/C Inhibition during Spindle Assembly Checkpoint Signaling. Curr Biol 2017; 27:2915-2927.e7. [PMID: 28943088 PMCID: PMC5640511 DOI: 10.1016/j.cub.2017.08.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 07/16/2017] [Accepted: 08/15/2017] [Indexed: 12/25/2022]
Abstract
The spindle assembly checkpoint (SAC) prevents premature sister chromatid separation during mitosis. Phosphorylation of unattached kinetochores by the Mps1 kinase promotes recruitment of SAC machinery that catalyzes assembly of the SAC effector mitotic checkpoint complex (MCC). The SAC protein Bub3 is a phospho-amino acid adaptor that forms structurally related stable complexes with functionally distinct paralogs named Bub1 and BubR1. A short motif (“loop”) of Bub1, but not the equivalent loop of BubR1, enhances binding of Bub3 to kinetochore phospho-targets. Here, we asked whether the BubR1 loop directs Bub3 to different phospho-targets. The BubR1 loop is essential for SAC function and cannot be removed or replaced with the Bub1 loop. BubR1 loop mutants bind Bub3 and are normally incorporated in MCC in vitro but have reduced ability to inhibit the MCC target anaphase-promoting complex (APC/C), suggesting that BubR1:Bub3 recognition and inhibition of APC/C requires phosphorylation. Thus, small sequence differences in Bub1 and BubR1 direct Bub3 to different phosphorylated targets in the SAC signaling cascade. The molecular basis of kinetochore recruitment of Bub1 and BubR1 is dissected Bub1 and BubR1 modulate the ability of Bub3 to recognize phosphorylated targets A newly identified BubR1 motif targets Bub3 to the anaphase-promoting complex The newly identified motif of BubR1 is required for checkpoint signaling
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Affiliation(s)
- Katharina Overlack
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Tanja Bange
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Florian Weissmann
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Alex C Faesen
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Stefano Maffini
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Ivana Primorac
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Franziska Müller
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - 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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29
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van Hooff JJ, Tromer E, van Wijk LM, Snel B, Kops GJ. Evolutionary dynamics of the kinetochore network in eukaryotes as revealed by comparative genomics. EMBO Rep 2017. [PMID: 28642229 PMCID: PMC5579357 DOI: 10.15252/embr.201744102] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
During eukaryotic cell division, the sister chromatids of duplicated chromosomes are pulled apart by microtubules, which connect via kinetochores. The kinetochore is a multiprotein structure that links centromeres to microtubules, and that emits molecular signals in order to safeguard the equal distribution of duplicated chromosomes over daughter cells. Although microtubule‐mediated chromosome segregation is evolutionary conserved, kinetochore compositions seem to have diverged. To systematically inventory kinetochore diversity and to reconstruct its evolution, we determined orthologs of 70 kinetochore proteins in 90 phylogenetically diverse eukaryotes. The resulting ortholog sets imply that the last eukaryotic common ancestor (LECA) possessed a complex kinetochore and highlight that current‐day kinetochores differ substantially. These kinetochores diverged through gene loss, duplication, and, less frequently, invention and displacement. Various kinetochore components co‐evolved with one another, albeit in different manners. These co‐evolutionary patterns improve our understanding of kinetochore function and evolution, which we illustrated with the RZZ complex, TRIP13, the MCC, and some nuclear pore proteins. The extensive diversity of kinetochore compositions in eukaryotes poses numerous questions regarding evolutionary flexibility of essential cellular functions.
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Affiliation(s)
- Jolien Je van Hooff
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,Theoretical Biology and Bioinformatics, Department of Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands.,Molecular Cancer Research, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Eelco Tromer
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,Theoretical Biology and Bioinformatics, Department of Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands
| | - Leny M van Wijk
- Theoretical Biology and Bioinformatics, Department of Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Department of Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands
| | - Geert Jpl Kops
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands .,Molecular Cancer Research, University Medical Center Utrecht, Utrecht, The Netherlands.,Cancer Genomics Netherlands, University Medical Center Utrecht, Utrecht, The Netherlands
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30
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May KM, Paldi F, Hardwick KG. Fission Yeast Apc15 Stabilizes MCC-Cdc20-APC/C Complexes, Ensuring Efficient Cdc20 Ubiquitination and Checkpoint Arrest. Curr Biol 2017; 27:1221-1228. [PMID: 28366744 PMCID: PMC5405113 DOI: 10.1016/j.cub.2017.03.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/03/2017] [Accepted: 03/08/2017] [Indexed: 12/16/2022]
Abstract
During mitosis, cells must segregate the replicated copies of their genome to their daughter cells with extremely high fidelity. Segregation errors lead to an abnormal chromosome number (aneuploidy), which typically results in disease or cell death [1]. Chromosome segregation and anaphase onset are initiated through the action of the multi-subunit E3 ubiquitin ligase known as the anaphase-promoting complex or cyclosome (APC/C [2]). The APC/C is inhibited by the spindle checkpoint in the presence of kinetochore attachment defects [3, 4]. Here we demonstrate that two non-essential APC/C subunits (Apc14 and Apc15) regulate association of spindle checkpoint proteins, in the form of the mitotic checkpoint complex (MCC), with the APC/C. apc14Δ mutants display increased MCC association with the APC/C and are unable to silence the checkpoint efficiently. Conversely, apc15Δ mutants display reduced association between the MCC and APC/C, are defective in poly-ubiquitination of Cdc20, and are checkpoint defective. In vitro reconstitution studies have shown that human MCC-APC/C can contain two molecules of Cdc20 [5-7]. Using a yeast strain expressing two Cdc20 genes with different epitope tags, we show by co-immunoprecipitation that this is true in vivo. MCC binding to the second molecule of Cdc20 is mediated via the C-terminal KEN box in Mad3. Somewhat surprisingly, complexes containing both molecules of Cdc20 accumulate in apc15Δ cells, and the implications of this observation are discussed.
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Affiliation(s)
- Karen M May
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Flora Paldi
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Kevin G Hardwick
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK.
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31
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Different Functionality of Cdc20 Binding Sites within the Mitotic Checkpoint Complex. Curr Biol 2017; 27:1213-1220. [PMID: 28366743 DOI: 10.1016/j.cub.2017.03.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/28/2017] [Accepted: 03/03/2017] [Indexed: 11/21/2022]
Abstract
The mitotic checkpoint is a cellular safeguard that prevents chromosome missegregation in eukaryotic cells [1, 2]. Suboptimal functioning may foster chromosome missegregation in cancer cells [3]. Checkpoint signaling produces the "mitotic checkpoint complex" (MCC), which prevents anaphase by targeting Cdc20, the activator of the anaphase-promoting complex/cyclosome (APC/C). Recent biochemical and structural studies revealed that the human MCC binds two Cdc20 molecules, one (Cdc20M) through well-characterized, cooperative binding to Mad2 and Mad3/BubR1 (forming the "core MCC") and the other one (Cdc20A) through additional binding sequences in Mad3/BubR1 [4-6]. Here, we dissect the different functionality of these sites in vivo. We show in fission yeast that, at low Cdc20 concentrations, Cdc20M binding is sufficient for checkpoint activity and Cdc20A binding becomes dispensable. Cdc20A binding is mediated by the conserved Mad3 ABBA-KEN2-ABBA motif [7, 8], which we find additionally required for binding of the MCC to the APC/C and for MCC disassembly. Strikingly, deletion of the APC/C subunit Apc15 mimics mutations in this motif, revealing a shared function. This function of Apc15 may be masked in human cells by independent mediators of MCC-APC/C binding. Our data provide important in vivo support for the recent structure-based models and functionally dissect three elements of Cdc20 inhibition: (1) sequestration of Cdc20 in the core MCC, sufficient at low Cdc20 concentrations; (2) inhibition of a second Cdc20 through the Mad3 C terminus, independent of Mad2 binding to this Cdc20 molecule; and (3) occupancy of the APC/C with full MCC, where Mad3 and Apc15 are involved.
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