1
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Anbalagan GK, Agarwal P, Ghosh SK. Evidence of 14-3-3 proteins contributing to kinetochore integrity and chromosome congression during mitosis. J Cell Sci 2024; 137:jcs261928. [PMID: 38988319 DOI: 10.1242/jcs.261928] [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: 12/24/2023] [Accepted: 07/05/2024] [Indexed: 07/12/2024] Open
Abstract
The 14-3-3 family of proteins are conserved across eukaryotes and serve myriad important regulatory functions in the cell. Homo- and hetero-dimers of these proteins mainly recognize their ligands via conserved motifs to modulate the localization and functions of those effector ligands. In most of the genetic backgrounds of Saccharomyces cerevisiae, disruption of both 14-3-3 homologs (Bmh1 and Bmh2) are either lethal or cells survive with severe growth defects, including gross chromosomal missegregation and prolonged cell cycle arrest. To elucidate their contributions to chromosome segregation, in this work, we investigated their centromere- and kinetochore-related functions of Bmh1 and Bmh2. Analysis of appropriate deletion mutants shows that Bmh isoforms have cumulative and non-shared isoform-specific contributions in maintaining the proper integrity of the kinetochore ensemble. Consequently, Bmh mutant cells exhibited perturbations in kinetochore-microtubule (KT-MT) dynamics, characterized by kinetochore declustering, mis-localization of kinetochore proteins and Mad2-mediated transient G2/M arrest. These defects also caused an asynchronous chromosome congression in bmh mutants during metaphase. In summary, this report advances the knowledge on contributions of budding yeast 14-3-3 proteins in chromosome segregation by demonstrating their roles in kinetochore integrity and chromosome congression.
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Affiliation(s)
| | - Prakhar Agarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, 400 076, India
| | - Santanu Kumar Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, 400 076, India
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2
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Andrade Ruiz L, Kops GJPL, Sacristan C. Vertebrate centromere architecture: from chromatin threads to functional structures. Chromosoma 2024; 133:169-181. [PMID: 38856923 PMCID: PMC11266386 DOI: 10.1007/s00412-024-00823-z] [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] [Received: 01/06/2024] [Revised: 05/21/2024] [Accepted: 05/27/2024] [Indexed: 06/11/2024]
Abstract
Centromeres are chromatin structures specialized in sister chromatid cohesion, kinetochore assembly, and microtubule attachment during chromosome segregation. The regional centromere of vertebrates consists of long regions of highly repetitive sequences occupied by the Histone H3 variant CENP-A, and which are flanked by pericentromeres. The three-dimensional organization of centromeric chromatin is paramount for its functionality and its ability to withstand spindle forces. Alongside CENP-A, key contributors to the folding of this structure include components of the Constitutive Centromere-Associated Network (CCAN), the protein CENP-B, and condensin and cohesin complexes. Despite its importance, the intricate architecture of the regional centromere of vertebrates remains largely unknown. Recent advancements in long-read sequencing, super-resolution and cryo-electron microscopy, and chromosome conformation capture techniques have significantly improved our understanding of this structure at various levels, from the linear arrangement of centromeric sequences and their epigenetic landscape to their higher-order compaction. In this review, we discuss the latest insights on centromere organization and place them in the context of recent findings describing a bipartite higher-order organization of the centromere.
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Affiliation(s)
- Lorena Andrade Ruiz
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands
- University Medical Center Utrecht, Utrecht, Netherlands
- Oncode Institute, Utrecht, Netherlands
| | - Geert J P L Kops
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands
- University Medical Center Utrecht, Utrecht, Netherlands
- Oncode Institute, Utrecht, Netherlands
| | - Carlos Sacristan
- Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences, Utrecht, Netherlands.
- University Medical Center Utrecht, Utrecht, Netherlands.
- Oncode Institute, Utrecht, Netherlands.
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3
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Zahm JA, Harrison SC. A communication hub for phosphoregulation of kinetochore-microtubule attachment. Curr Biol 2024; 34:2308-2318.e6. [PMID: 38776904 DOI: 10.1016/j.cub.2024.04.067] [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] [Received: 11/22/2023] [Revised: 04/06/2024] [Accepted: 04/29/2024] [Indexed: 05/25/2024]
Abstract
The Mps1 and Aurora B kinases regulate and monitor kinetochore attachment to spindle microtubules during cell division, ultimately ensuring accurate chromosome segregation. In yeast, the critical spindle attachment components are the Ndc80 and Dam1 complexes (Ndc80c and DASH/Dam1c, respectively). Ndc80c is a 600-Å-long heterotetramer that binds microtubules through a globular "head" at one end and centromere-proximal kinetochore components through a globular knob at the other end. Dam1c is a heterodecamer that forms a ring of 16-17 protomers around the shaft of the single kinetochore microtubule in point-centromere yeast. The ring coordinates the approximately eight Ndc80c rods per kinetochore. In published work, we showed that a site on the globular "head" of Ndc80c, including residues from both Ndc80 and Nuf2, binds a bipartite segment in the long C-terminal extension of Dam1. Results reported here show, both by in vitro binding experiments and by crystal structure determination, that the same site binds a conserved segment in the long N-terminal extension of Mps1. It also binds, less tightly, a conserved segment in the N-terminal extension of Ipl1 (yeast Aurora B). Together with results from experiments in yeast cells and from biochemical assays reported in two accompanying papers, the structures and graded affinities identify a communication hub for ensuring uniform bipolar attachment and for signaling anaphase onset.
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Affiliation(s)
- Jacob A Zahm
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
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4
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Richeldi M, Pobegalov G, Higashi TL, Gmurczyk K, Uhlmann F, Molodtsov MI. Mechanical disengagement of the cohesin ring. Nat Struct Mol Biol 2024; 31:23-31. [PMID: 37872232 DOI: 10.1038/s41594-023-01122-4] [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: 11/11/2022] [Accepted: 09/11/2023] [Indexed: 10/25/2023]
Abstract
Cohesin forms a proteinaceous ring that is thought to link sister chromatids by entrapping DNA and counteracting the forces generated by the mitotic spindle. Whether individual cohesins encircle both sister DNAs and how cohesin opposes spindle-generated forces remains unknown. Here we perform force measurements on individual yeast cohesin complexes either bound to DNA or holding together two DNAs. By covalently closing the hinge and Smc3Psm3-kleisin interfaces we find that the mechanical stability of the cohesin ring entrapping DNA is determined by the hinge domain. Forces of ~20 pN disengage cohesin at the hinge and release DNA, indicating that ~40 cohesin molecules are sufficient to counteract known spindle forces. Our findings provide a mechanical framework for understanding how cohesin interacts with sister chromatids and opposes the spindle-generated tension during mitosis, with implications for other force-generating chromosomal processes including transcription and DNA replication.
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Affiliation(s)
- Martina Richeldi
- Biophysics and Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Georgii Pobegalov
- Biophysics and Mechanobiology Laboratory, The Francis Crick Institute, London, UK
- Department of Physics and Astronomy, University College London, London, UK
| | - Torahiko L Higashi
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
- Kamakura Research Laboratories, Chugai Pharmaceutical Co., Kamakura City, Japan
| | - Karolina Gmurczyk
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK.
| | - Maxim I Molodtsov
- Biophysics and Mechanobiology Laboratory, The Francis Crick Institute, London, UK.
- Department of Physics and Astronomy, University College London, London, UK.
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5
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Parmar S, Gonzalez SJ, Heckel JM, Mukherjee S, McClellan M, Clarke DJ, Johansson M, Tank D, Geisness A, Wood DK, Gardner MK. Robust microtubule dynamics facilitate low-tension kinetochore detachment in metaphase. J Cell Biol 2023; 222:e202202085. [PMID: 37166419 PMCID: PMC10182774 DOI: 10.1083/jcb.202202085] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 02/07/2023] [Accepted: 04/24/2023] [Indexed: 05/12/2023] Open
Abstract
During mitosis, sister chromatids are stretched apart at their centromeres via their attachment to oppositely oriented kinetochore microtubules. This stretching generates inwardly directed tension across the separated sister centromeres. The cell leverages this tension signal to detect and then correct potential errors in chromosome segregation, via a mechanical tension signaling pathway that detaches improperly attached kinetochores from their microtubules. However, the sequence of events leading up to these detachment events remains unknown. In this study, we used microfluidics to sustain and observe low-tension budding yeast metaphase spindles over multiple hours, allowing us to elucidate the tension history prior to a detachment event. We found that, under conditions in which kinetochore phosphorylation weakens low-tension kinetochore-microtubule connections, the mechanical forces produced via the dynamic growth and shortening of microtubules is required to efficiently facilitate detachment events. Our findings underscore the critical role of robust kinetochore microtubule dynamics in ensuring the fidelity of chromosome segregation during mitosis.
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Affiliation(s)
- Sneha Parmar
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Samuel J. Gonzalez
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Julia M. Heckel
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Soumya Mukherjee
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Mark McClellan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Duncan J. Clarke
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Marnie Johansson
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Damien Tank
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
| | - Athena Geisness
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - David K. Wood
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Melissa K. Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN, USA
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6
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Choudhary K, Kupiec M. The cohesin complex of yeasts: sister chromatid cohesion and beyond. FEMS Microbiol Rev 2023; 47:6825453. [PMID: 36370456 DOI: 10.1093/femsre/fuac045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/13/2022] Open
Abstract
Each time a cell divides, it needs to duplicate the genome and then separate the two copies. In eukaryotes, which usually have more than one linear chromosome, this entails tethering the two newly replicated DNA molecules, a phenomenon known as sister chromatid cohesion (SCC). Cohesion ensures proper chromosome segregation to separate poles during mitosis. SCC is achieved by the presence of the cohesin complex. Besides its canonical function, cohesin is essential for chromosome organization and DNA damage repair. Surprisingly, yeast cohesin is loaded in G1 before DNA replication starts but only acquires its binding activity during DNA replication. Work in microorganisms, such as Saccharomyces cerevisiae and Schizosaccharomyces pombe has greatly contributed to the understanding of cohesin composition and functions. In the last few years, much progress has been made in elucidating the role of cohesin in chromosome organization and compaction. Here, we discuss the different functions of cohesin to ensure faithful chromosome segregation and genome stability during the mitotic cell division in yeast. We describe what is known about its composition and how DNA replication is coupled with SCC establishment. We also discuss current models for the role of cohesin in chromatin loop extrusion and delineate unanswered questions about the activity of this important, conserved complex.
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Affiliation(s)
- Karan Choudhary
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Martin Kupiec
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Ramat Aviv 69978, Israel
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7
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Matityahu A, Onn I. It's all in the numbers: Cohesin stoichiometry. Front Mol Biosci 2022; 9:1010894. [PMID: 36330215 PMCID: PMC9623059 DOI: 10.3389/fmolb.2022.1010894] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 10/05/2022] [Indexed: 01/09/2024] Open
Abstract
Cohesin, a structural maintenance of chromosome (SMC) complex, organizes chromatin into three-dimensional structures by threading chromatin into loops and stabilizing long-range chromatin interactions. Four subunits in a 1:1:1:1 ratio compose the cohesin core, which is regulated by auxiliary factors that interact with or modify the core subunits. An ongoing debate about cohesin's mechanism of action regards its stoichiometry. Namely, is cohesin activity mediated by a single complex or cooperation between several complexes that organize into dimers or oligomers? Several investigations that used various experimental approaches have tried to resolve this dispute. Some have convincingly demonstrated that the cohesin monomer is the active unit. However, others have revealed the formation of cohesin dimers and higher-order clusters on and off chromosomes. Elucidating the biological function of cohesin clusters and determining what regulates their formation are just two of the many new questions raised by these findings. We briefly review the history of the argument about cohesin stoichiometry and the central evidence for cohesin activity as a monomer vs. an oligomer. Finally, we discuss the possible biological significance of cohesin oligomerization and present open questions that remain to be answered.
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Affiliation(s)
| | - Itay Onn
- The Azrieli Faculty of Medicine, Bar-Ilan University, Ramat Gan, Safed, Israel
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8
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Sen S, Dodamani A, Nambiar M. Emerging mechanisms and roles of meiotic crossover repression at centromeres. Curr Top Dev Biol 2022; 151:155-190. [PMID: 36681469 DOI: 10.1016/bs.ctdb.2022.06.003] [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: 01/25/2023]
Abstract
Crossover events during recombination in meiosis are essential for generating genetic diversity as well as crucial to allow accurate chromosomal segregation between homologous chromosomes. Spatial control for the distribution of crossover events along the chromosomes is largely a tightly regulated process and involves many facets such as interference, repression as well as assurance, to make sure that not too many or too few crossovers are generated. Repression of crossover events at the centromeres is a highly conserved process across all species tested. Failure to inhibit such recombination events can result in chromosomal mis-segregation during meiosis resulting in aneuploid gametes that are responsible for infertility or developmental disorders such as Down's syndrome and other trisomies in humans. In the past few decades, studies to understand the molecular mechanisms behind this repression have shown the involvement of a multitude of factors ranging from the centromere-specific proteins such as the kinetochore to the flanking pericentric heterochromatin as well as DNA double-strand break repair pathways. In this chapter, we review the different mechanisms of pericentric repression mechanisms known till date as well as highlight the importance of understanding this regulation in the context of chromosomal segregation defects. We also discuss the clinical implications of dysregulation of this process, especially in human reproductive health and genetic diseases.
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Affiliation(s)
- Sucharita Sen
- Department of Biology, Indian Institute of Science Education and Research, Pune, India
| | - Ananya Dodamani
- Department of Biology, Indian Institute of Science Education and Research, Pune, India
| | - Mridula Nambiar
- Department of Biology, Indian Institute of Science Education and Research, Pune, India.
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9
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CCAR2 controls mitotic progression through spatiotemporal regulation of Aurora B. Cell Death Dis 2022; 13:534. [PMID: 35672287 PMCID: PMC9174277 DOI: 10.1038/s41419-022-04990-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 05/27/2022] [Accepted: 05/30/2022] [Indexed: 01/21/2023]
Abstract
CCAR2 (cell cycle and apoptosis regulator 2) is a multifaceted protein involved in cell survival and death following cytotoxic stress. However, little is known about the physiological functions of CCAR2 in regulating cell proliferation in the absence of external stimuli. The present study shows that CCAR2-deficient cells possess multilobulated nuclei, suggesting a defect in cell division. In particular, the duration of mitotic phase was perturbed. This disturbance of mitotic progression resulted from premature loss of cohesion with the centromere, and inactivation of the spindle assembly checkpoint during prometaphase and metaphase. It resulted in the formation of lagging chromosomes during anaphase, leading ultimately to the activation of the abscission checkpoint to halt cytokinesis. The CCAR2-dependent mitotic progression was related to spatiotemporal regulation of active Aurora B. In conclusion, the results suggest that CCAR2 governs mitotic events, including proper chromosome segregation and cytokinetic division, to maintain chromosomal stability.
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10
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Schedel A, Friedrich UA, Morcos MNF, Wagener R, Mehtonen J, Watrin T, Saitta C, Brozou T, Michler P, Walter C, Försti A, Baksi A, Menzel M, Horak P, Paramasivam N, Fazio G, Autry RJ, Fröhling S, Suttorp M, Gertzen C, Gohlke H, Bhatia S, Wadt K, Schmiegelow K, Dugas M, Richter D, Glimm H, Heinäniemi M, Jessberger R, Cazzaniga G, Borkhardt A, Hauer J, Auer F. Recurrent Germline Variant in RAD21 Predisposes Children to Lymphoblastic Leukemia or Lymphoma. Int J Mol Sci 2022; 23:ijms23095174. [PMID: 35563565 PMCID: PMC9106003 DOI: 10.3390/ijms23095174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 05/02/2022] [Indexed: 12/04/2022] Open
Abstract
Somatic loss of function mutations in cohesin genes are frequently associated with various cancer types, while cohesin disruption in the germline causes cohesinopathies such as Cornelia-de-Lange syndrome (CdLS). Here, we present the discovery of a recurrent heterozygous RAD21 germline aberration at amino acid position 298 (p.P298S/A) identified in three children with lymphoblastic leukemia or lymphoma in a total dataset of 482 pediatric cancer patients. While RAD21 p.P298S/A did not disrupt the formation of the cohesin complex, it altered RAD21 gene expression, DNA damage response and primary patient fibroblasts showed increased G2/M arrest after irradiation and Mitomycin-C treatment. Subsequent single-cell RNA-sequencing analysis of healthy human bone marrow confirmed the upregulation of distinct cohesin gene patterns during hematopoiesis, highlighting the importance of RAD21 expression within proliferating B- and T-cells. Our clinical and functional data therefore suggest that RAD21 germline variants can predispose to childhood lymphoblastic leukemia or lymphoma without displaying a CdLS phenotype.
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Affiliation(s)
- Anne Schedel
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.S.); (U.A.F.); (P.M.); (M.M.); (M.S.)
| | - Ulrike Anne Friedrich
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.S.); (U.A.F.); (P.M.); (M.M.); (M.S.)
| | - Mina N. F. Morcos
- Department of Pediatrics, School of Medicine, Technical University of Munich; 80804 Munich, Germany; (M.N.F.M.); (F.A.)
| | - Rabea Wagener
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich-Heine University Duesseldorf, Medical Faculty, 40225 Duesseldorf, Germany; (R.W.); (T.W.); (T.B.); (S.B.); (A.B.)
| | - Juha Mehtonen
- Institute of Biomedicine, School of Medicine, University of Eastern Finland, Yliopistonranta 1, FI-70211 Kuopio, Finland; (J.M.); (M.H.)
| | - Titus Watrin
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich-Heine University Duesseldorf, Medical Faculty, 40225 Duesseldorf, Germany; (R.W.); (T.W.); (T.B.); (S.B.); (A.B.)
| | - Claudia Saitta
- Tettamanti Research Center, Pediatrics, University of Milan Bicocca, Fondazione MBBM/San Gerardo Hospital, 20900 Monza, Italy; (C.S.); (G.F.); (G.C.)
| | - Triantafyllia Brozou
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich-Heine University Duesseldorf, Medical Faculty, 40225 Duesseldorf, Germany; (R.W.); (T.W.); (T.B.); (S.B.); (A.B.)
| | - Pia Michler
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.S.); (U.A.F.); (P.M.); (M.M.); (M.S.)
| | - Carolin Walter
- Institute of Medical Informatics, University of Muenster, 48149 Muenster, Germany; (C.W.); (M.D.)
| | - Asta Försti
- Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), German Cancer Consortium (DKTK), 69120 Heidelberg, Germany; (A.F.); (R.J.A.)
- Hopp Children’s Cancer Center Heidelberg (KiTZ), 69120 Heidelberg, Germany
| | - Arka Baksi
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.B.); (R.J.)
| | - Maria Menzel
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.S.); (U.A.F.); (P.M.); (M.M.); (M.S.)
| | - Peter Horak
- Division of Translational Medical Oncology, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; (P.H.); (S.F.)
| | - Nagarajan Paramasivam
- Computational Oncology, Molecular Diagnostics Program, National Center for Tumor Diseases (NCT), 69120 Heidelberg, Germany;
| | - Grazia Fazio
- Tettamanti Research Center, Pediatrics, University of Milan Bicocca, Fondazione MBBM/San Gerardo Hospital, 20900 Monza, Italy; (C.S.); (G.F.); (G.C.)
| | - Robert J Autry
- Division of Pediatric Neurooncology, German Cancer Research Center (DKFZ), German Cancer Consortium (DKTK), 69120 Heidelberg, Germany; (A.F.); (R.J.A.)
- Hopp Children’s Cancer Center Heidelberg (KiTZ), 69120 Heidelberg, Germany
| | - Stefan Fröhling
- Division of Translational Medical Oncology, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany; (P.H.); (S.F.)
| | - Meinolf Suttorp
- Pediatric Hematology and Oncology, Department of Pediatrics, University Hospital Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.S.); (U.A.F.); (P.M.); (M.M.); (M.S.)
| | - Christoph Gertzen
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Duesseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (C.G.); (H.G.)
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Duesseldorf, Universitätsstraße 1, 40225 Duesseldorf, Germany; (C.G.); (H.G.)
- John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Sanil Bhatia
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich-Heine University Duesseldorf, Medical Faculty, 40225 Duesseldorf, Germany; (R.W.); (T.W.); (T.B.); (S.B.); (A.B.)
| | - Karin Wadt
- Department of Clinical Genetics, University Hospital of Copenhagen, Faculty of health and Medical Sciences, University of Copenhagen, 2100 Copenhagen, Denmark;
| | - Kjeld Schmiegelow
- Department of Paediatrics and Adolescent Medicine, Copenhagen University Hospital Rigshospitalet, 2100 Copenhagen, Denmark;
| | - Martin Dugas
- Institute of Medical Informatics, University of Muenster, 48149 Muenster, Germany; (C.W.); (M.D.)
- Institute of Medical Informatics, Heidelberg University Hospital, 69120 Heidelberg, Germany
| | - Daniela Richter
- Department of Translational Medical Oncology, National Center for Tumor Diseases (NCT) Dresden, 01307 Dresden, Germany; (D.R.); (H.G.)
- German Cancer Consortium (DKTK), 01307 Dresden, Germany
| | - Hanno Glimm
- Department of Translational Medical Oncology, National Center for Tumor Diseases (NCT) Dresden, 01307 Dresden, Germany; (D.R.); (H.G.)
- German Cancer Consortium (DKTK), 01307 Dresden, Germany
- Translational Functional Cancer Genomics, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Merja Heinäniemi
- Institute of Biomedicine, School of Medicine, University of Eastern Finland, Yliopistonranta 1, FI-70211 Kuopio, Finland; (J.M.); (M.H.)
| | - Rolf Jessberger
- Institute of Physiological Chemistry, Medical Faculty Carl Gustav Carus, TU Dresden, 01307 Dresden, Germany; (A.B.); (R.J.)
| | - Gianni Cazzaniga
- Tettamanti Research Center, Pediatrics, University of Milan Bicocca, Fondazione MBBM/San Gerardo Hospital, 20900 Monza, Italy; (C.S.); (G.F.); (G.C.)
- Medical Genetics, Department of Medicine and Surgery, University of Milan Bicocca, 20900 Monza, Italy
| | - Arndt Borkhardt
- Department of Pediatric Oncology, Hematology and Clinical Immunology, Heinrich-Heine University Duesseldorf, Medical Faculty, 40225 Duesseldorf, Germany; (R.W.); (T.W.); (T.B.); (S.B.); (A.B.)
| | - Julia Hauer
- Department of Pediatrics, School of Medicine, Technical University of Munich; 80804 Munich, Germany; (M.N.F.M.); (F.A.)
- German Cancer Consortium (DKTK), 81675 Munich, Germany
- Correspondence: ; Tel.: +49-(89)-3068-3940
| | - Franziska Auer
- Department of Pediatrics, School of Medicine, Technical University of Munich; 80804 Munich, Germany; (M.N.F.M.); (F.A.)
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11
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SWAP, SWITCH, and STABILIZE: Mechanisms of Kinetochore–Microtubule Error Correction. Cells 2022; 11:cells11091462. [PMID: 35563768 PMCID: PMC9104000 DOI: 10.3390/cells11091462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/20/2022] [Accepted: 04/21/2022] [Indexed: 11/17/2022] Open
Abstract
For correct chromosome segregation in mitosis, eukaryotic cells must establish chromosome biorientation where sister kinetochores attach to microtubules extending from opposite spindle poles. To establish biorientation, any aberrant kinetochore–microtubule interactions must be resolved in the process called error correction. For resolution of the aberrant interactions in error correction, kinetochore–microtubule interactions must be exchanged until biorientation is formed (the SWAP process). At initiation of biorientation, the state of weak kinetochore–microtubule interactions should be converted to the state of stable interactions (the SWITCH process)—the conundrum of this conversion is called the initiation problem of biorientation. Once biorientation is established, tension is applied on kinetochore–microtubule interactions, which stabilizes the interactions (the STABILIZE process). Aurora B kinase plays central roles in promoting error correction, and Mps1 kinase and Stu2 microtubule polymerase also play important roles. In this article, we review mechanisms of error correction by considering the SWAP, SWITCH, and STABILIZE processes. We mainly focus on mechanisms found in budding yeast, where only one microtubule attaches to a single kinetochore at biorientation, making the error correction mechanisms relatively simpler.
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12
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Xu X, Kanai R, Wang L, Yanagida M. Single amino acid substitutions in hydrophobic cores at a head-coiled coil junction region of cohesin facilitate its release of DNA during anaphase. Open Biol 2022; 12:210275. [PMID: 35472286 PMCID: PMC9042573 DOI: 10.1098/rsob.210275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 03/14/2022] [Indexed: 01/07/2023] Open
Abstract
Cohesin holds sister chromatids together and is cleaved by separase/Cut1 to release DNA during the transition from mitotic metaphase to anaphase. The cohesin complex consists of heterodimeric structural maintenance of chromosomes (SMC) subunits (Psm1 and Psm3), which possess a head and a hinge, separated by long coiled coils. Non-SMC subunits (Rad21, Psc3 and Mis4) bind to the SMC heads. Kleisin/Rad21's N-terminal domain (Rad21-NTD) interacts with Psm3's head-coiled coil junction (Psm3-HCJ). Spontaneous mutations that rescued the cleavage defects in temperature-sensitive (ts) separase mutants were identified in the interaction interface, but the underlying mechanism is yet to be understood. Here, we performed site-directed random mutagenesis to introduce single amino acid substitutions in Psm3-HCJ and Rad21-NTD, and then identified 300 mutations that rescued the cohesin-releasing defects in a separase ts mutant. Mutational analysis indicated that the amino acids involved in hydrophobic cores (which may be in close contact) in Psm3-HCJ and Rad21-NTD are hotspots, since 80 mutations (approx. 27%) were mapped in these locations. Properties of these substitutions indicate that they destabilize the interaction between the Psm3 head and Rad21-NTD. Thus, they may facilitate sister chromatid separation in a cleavage-independent way through cohesin structural re-arrangement.
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Affiliation(s)
- Xingya Xu
- G0 Cell Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0495, Japan
| | - Ryuta Kanai
- Institute of Quantitative Biosciences, The University of Tokyo, 113-0032 Tokyo, Japan
| | - Li Wang
- G0 Cell Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0495, Japan
| | - Mitsuhiro Yanagida
- G0 Cell Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0495, Japan
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13
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Abstract
The centromere serves as the binding site for the kinetochore and is essential for the faithful segregation of chromosomes throughout cell division. The point centromere in yeast is encoded by a ∼115 bp specific DNA sequence, whereas regional centromeres range from 6-10 kbp in fission yeast to 5-10 Mbp in humans. Understanding the physical structure of centromere chromatin (pericentromere in yeast), defined as the chromatin between sister kinetochores, will provide fundamental insights into how centromere DNA is woven into a stiff spring that is able to resist microtubule pulling forces during mitosis. One hallmark of the pericentromere is the enrichment of the structural maintenance of chromosome (SMC) proteins cohesin and condensin. Based on studies from population approaches (ChIP-seq and Hi-C) and experimentally obtained images of fluorescent probes of pericentromeric structure, as well as quantitative comparisons between simulations and experimental results, we suggest a mechanism for building tension between sister kinetochores. We propose that the centromere is a chromatin bottlebrush that is organized by the loop-extruding proteins condensin and cohesin. The bottlebrush arrangement provides a biophysical means to transform pericentromeric chromatin into a spring due to the steric repulsion between radial loops. We argue that the bottlebrush is an organizing principle for chromosome organization that has emerged from multiple approaches in the field.
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14
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Barton RE, Massari LF, Robertson D, Marston AL. Eco1-dependent cohesin acetylation anchors chromatin loops and cohesion to define functional meiotic chromosome domains. eLife 2022; 11:e74447. [PMID: 35103590 PMCID: PMC8856730 DOI: 10.7554/elife.74447] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Abstract
Cohesin organizes the genome by forming intra-chromosomal loops and inter-sister chromatid linkages. During gamete formation by meiosis, chromosomes are reshaped to support crossover recombination and two consecutive rounds of chromosome segregation. Here we show that meiotic chromosomes are organised into functional domains by Eco1 acetyltransferase-dependent positioning of both chromatin loops and sister chromatid cohesion in budding yeast. Eco1 acetylates the Smc3 cohesin subunit in meiotic S phase to establish chromatin boundaries, independently of DNA replication. Boundary formation by Eco1 is critical for prophase exit and for the maintenance of cohesion until meiosis II, but is independent of the ability of Eco1 to antagonize the cohesin-release factor, Wpl1. Conversely, prevention of cohesin release by Wpl1 is essential for centromeric cohesion, kinetochore monoorientation and co-segregation of sister chromatids in meiosis I. Our findings establish Eco1 as a key determinant of chromatin boundaries and cohesion positioning, revealing how local chromosome structuring directs genome transmission into gametes.
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Affiliation(s)
- Rachael E Barton
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, Michael Swann Building, Max Born CrescentEdinburghUnited Kingdom
| | - Lucia F Massari
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, Michael Swann Building, Max Born CrescentEdinburghUnited Kingdom
| | - Daniel Robertson
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, Michael Swann Building, Max Born CrescentEdinburghUnited Kingdom
| | - Adèle L Marston
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, Michael Swann Building, Max Born CrescentEdinburghUnited Kingdom
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15
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Sarangapani KK, Koch LB, Nelson CR, Asbury CL, Biggins S. Kinetochore-bound Mps1 regulates kinetochore-microtubule attachments via Ndc80 phosphorylation. J Cell Biol 2021; 220:e202106130. [PMID: 34647959 PMCID: PMC8641409 DOI: 10.1083/jcb.202106130] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 08/03/2021] [Accepted: 09/09/2021] [Indexed: 12/22/2022] Open
Abstract
Dividing cells detect and correct erroneous kinetochore-microtubule attachments during mitosis, thereby avoiding chromosome missegregation. The Aurora B kinase phosphorylates microtubule-binding elements specifically at incorrectly attached kinetochores, promoting their release and providing another chance for proper attachments to form. However, growing evidence suggests that the Mps1 kinase is also required for error correction. Here we directly examine how Mps1 activity affects kinetochore-microtubule attachments using a reconstitution-based approach that allows us to separate its effects from Aurora B activity. When endogenous Mps1 that copurifies with kinetochores is activated in vitro, it weakens their attachments to microtubules via phosphorylation of Ndc80, a major microtubule-binding protein. This phosphorylation contributes to error correction because phospho-deficient Ndc80 mutants exhibit genetic interactions and segregation defects when combined with mutants in other error correction pathways. In addition, Mps1 phosphorylation of Ndc80 is stimulated on kinetochores lacking tension. These data suggest that Mps1 provides an additional mechanism for correcting erroneous kinetochore-microtubule attachments, complementing the well-known activity of Aurora B.
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Affiliation(s)
| | - Lori B. Koch
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
- Molecular and Cellular Biology Program, University of Washington, Seattle, WA
| | - Christian R. Nelson
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Charles L. Asbury
- Department of Physiology & Biophysics, University of Washington, Seattle, WA
| | - Sue Biggins
- Howard Hughes Medical Institute, Chevy Chase, MD
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
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16
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Hassell DS, Steingesser MG, Denney AS, Johnson CR, McMurray MA. Chemical rescue of mutant proteins in living Saccharomyces cerevisiae cells by naturally occurring small molecules. G3-GENES GENOMES GENETICS 2021; 11:6323229. [PMID: 34544143 PMCID: PMC8496222 DOI: 10.1093/g3journal/jkab252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 06/29/2021] [Indexed: 11/14/2022]
Abstract
Intracellular proteins function in a complex milieu wherein small molecules influence protein folding and act as essential cofactors for enzymatic reactions. Thus protein function depends not only on amino acid sequence but also on the concentrations of such molecules, which are subject to wide variation between organisms, metabolic states, and environmental conditions. We previously found evidence that exogenous guanidine reverses the phenotypes of specific budding yeast septin mutants by binding to a WT septin at the former site of an Arg side chain that was lost during fungal evolution. Here, we used a combination of targeted and unbiased approaches to look for other cases of "chemical rescue" by naturally occurring small molecules. We report in vivo rescue of hundreds of Saccharomyces cerevisiae mutants representing a variety of genes, including likely examples of Arg or Lys side chain replacement by the guanidinium ion. Failed rescue of targeted mutants highlight features required for rescue, as well as key differences between the in vitro and in vivo environments. Some non-Arg mutants rescued by guanidine likely result from "off-target" effects on specific cellular processes in WT cells. Molecules isosteric to guanidine and known to influence protein folding had a range of effects, from essentially none for urea, to rescue of a few mutants by DMSO. Strikingly, the osmolyte trimethylamine-N-oxide rescued ∼20% of the mutants we tested, likely reflecting combinations of direct and indirect effects on mutant protein function. Our findings illustrate the potential of natural small molecules as therapeutic interventions and drivers of evolution.
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Affiliation(s)
- Daniel S Hassell
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Marc G Steingesser
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Ashley S Denney
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Courtney R Johnson
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Michael A McMurray
- Department of Cell and Developmental Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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17
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Aurora B Tension Sensing Mechanisms in the Kinetochore Ensure Accurate Chromosome Segregation. Int J Mol Sci 2021; 22:ijms22168818. [PMID: 34445523 PMCID: PMC8396173 DOI: 10.3390/ijms22168818] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 08/11/2021] [Accepted: 08/13/2021] [Indexed: 11/29/2022] Open
Abstract
The accurate segregation of chromosomes is essential for the survival of organisms and cells. Mistakes can lead to aneuploidy, tumorigenesis and congenital birth defects. The spindle assembly checkpoint ensures that chromosomes properly align on the spindle, with sister chromatids attached to microtubules from opposite poles. Here, we review how tension is used to identify and selectively destabilize incorrect attachments, and thus serves as a trigger of the spindle assembly checkpoint to ensure fidelity in chromosome segregation. Tension is generated on properly attached chromosomes as sister chromatids are pulled in opposing directions but resisted by centromeric cohesin. We discuss the role of the Aurora B kinase in tension-sensing and explore the current models for translating mechanical force into Aurora B-mediated biochemical signals that regulate correction of chromosome attachments to the spindle.
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18
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Proudfoot KG, Anderson SJ, Dave S, Bunning AR, Sinha Roy P, Bera A, Gupta ML. Checkpoint Proteins Bub1 and Bub3 Delay Anaphase Onset in Response to Low Tension Independent of Microtubule-Kinetochore Detachment. Cell Rep 2020; 27:416-428.e4. [PMID: 30970246 PMCID: PMC6485967 DOI: 10.1016/j.celrep.2019.03.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 05/18/2018] [Accepted: 03/08/2019] [Indexed: 11/23/2022] Open
Abstract
The spindle assembly checkpoint (SAC) delays anaphase onset until sister chromosomes are bound to microtubules from opposite spindle poles. Only then can dynamic microtubules produce tension across sister kinetochores. The interdependence of kinetochore attachment and tension has proved challenging to understanding SAC mechanisms. Whether the SAC responds simply to kinetochore attachment or to tension status remains obscure. Unlike higher eukaryotes, budding yeast kinetochores bind only one microtubule, simplifying the relation between attachment and tension. We developed a Taxol-sensitive yeast model to reduce tension in fully assembled spindles. Our results show that low tension on bipolar-attached kinetochores delays anaphase onset, independent of detachment. The delay is transient relative to that imposed by unattached kinetochores. Furthermore, it is mediated by Bub1 and Bub3, but not Mad1, Mad2, and Mad3 (BubR1). Our results demonstrate that reduced tension delays anaphase onset via a signal that is temporally and mechanistically distinct from that produced by unattached kinetochores. Kinetochore attachment and tension are critical for proper chromosome segregation, but isolating the contribution of either stimulus has been challenging. Using a Taxol-sensitive yeast model, Proudfoot et al. show that reducing tension specifically produces a delay in mitotic progression that is temporally and mechanistically distinct from that produced by unattached kinetochores.
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Affiliation(s)
- Kathleen G Proudfoot
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA; Molecular Genetics and Cell Biology, University of Chicago, Chicago, IL 60637, USA
| | - Samuel J Anderson
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Sandeep Dave
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Angela R Bunning
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Pallavi Sinha Roy
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Abesh Bera
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA
| | - Mohan L Gupta
- Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA.
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19
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Paldi F, Alver B, Robertson D, Schalbetter SA, Kerr A, Kelly DA, Baxter J, Neale MJ, Marston AL. Convergent genes shape budding yeast pericentromeres. Nature 2020; 582:119-123. [PMID: 32494069 PMCID: PMC7279958 DOI: 10.1038/s41586-020-2244-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Accepted: 02/25/2020] [Indexed: 11/08/2022]
Abstract
The three-dimensional architecture of the genome governs its maintenance, expression and transmission. The cohesin protein complex organizes the genome by topologically linking distant loci, and is highly enriched in specialized chromosomal domains surrounding centromeres, called pericentromeres1-6. Here we report the three-dimensional structure of pericentromeres in budding yeast (Saccharomyces cerevisiae) and establish the relationship between genome organization and function. We find that convergent genes mark pericentromere borders and, together with core centromeres, define their structure and function by positioning cohesin. Centromeres load cohesin, and convergent genes at pericentromere borders trap it. Each side of the pericentromere is organized into a looped conformation, with border convergent genes at the base. Microtubule attachment extends a single pericentromere loop, size-limited by convergent genes at its borders. Reorienting genes at borders into a tandem configuration repositions cohesin, enlarges the pericentromere and impairs chromosome biorientation during mitosis. Thus, the linear arrangement of transcriptional units together with targeted cohesin loading shapes pericentromeres into a structure that is competent for chromosome segregation. Our results reveal the architecture of the chromosomal region within which kinetochores are embedded, as well as the restructuring caused by microtubule attachment. Furthermore, we establish a direct, causal relationship between the three-dimensional genome organization of a specific chromosomal domain and cellular function.
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Affiliation(s)
- Flora Paldi
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Bonnie Alver
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Daniel Robertson
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | | | - Alastair Kerr
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - David A Kelly
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK
| | - Jonathan Baxter
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Matthew J Neale
- Genome Damage and Stability Centre, University of Sussex, Brighton, UK
| | - Adele L Marston
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, UK.
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20
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Wang H, Xu W, Sun Y, Lian Q, Wang C, Yu C, He C, Wang J, Ma H, Copenhaver GP, Wang Y. The cohesin loader SCC2 contains a PHD finger that is required for meiosis in land plants. PLoS Genet 2020; 16:e1008849. [PMID: 32516352 PMCID: PMC7304647 DOI: 10.1371/journal.pgen.1008849] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/19/2020] [Accepted: 05/11/2020] [Indexed: 12/13/2022] Open
Abstract
Cohesin, a multisubunit protein complex, is required for holding sister chromatids together during mitosis and meiosis. The recruitment of cohesin by the sister chromatid cohesion 2/4 (SCC2/4) complex has been extensively studied in Saccharomyces cerevisiae mitosis, but its role in mitosis and meiosis remains poorly understood in multicellular organisms, because complete loss-of-function of either gene causes embryonic lethality. Here, we identified a weak allele of Atscc2 (Atscc2-5) that has only minor defects in vegetative development but exhibits a significant reduction in fertility. Cytological analyses of Atscc2-5 reveal multiple meiotic phenotypes including defects in chromosomal axis formation, meiosis-specific cohesin loading, homolog pairing and synapsis, and AtSPO11-1-dependent double strand break repair. Surprisingly, even though AtSCC2 interacts with AtSCC4 in vitro and in vivo, meiosis-specific knockdown of AtSCC4 expression does not cause any meiotic defect, suggesting that the SCC2-SCC4 complex has divergent roles in mitosis and meiosis. SCC2 homologs from land plants have a unique plant homeodomain (PHD) motif not found in other species. We show that the AtSCC2 PHD domain can bind to the N terminus of histones and is required for meiosis but not mitosis. Taken together, our results provide evidence that unlike SCC2 in other organisms, SCC2 requires a functional PHD domain during meiosis in land plants.
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Affiliation(s)
- Hongkuan Wang
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
- Center for Epigenetics, Van Andel Institute, Grand Rapids, Michigan, United States of America
| | - Wanyue Xu
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Yujin Sun
- Department of Biology and the Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Qichao Lian
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Cong Wang
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Chaoyi Yu
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Chengpeng He
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Jun Wang
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
| | - Hong Ma
- Department of Biology, the Huck Institutes of the Life Sciences, the Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Gregory P. Copenhaver
- Department of Biology and the Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Yingxiang Wang
- State Key Laboratory of Genetic Engineering and Ministry of Education Key Laboratory of Biodiversity Sciences and Ecological Engineering, Institute of Plant Biology, School of Life Sciences, Fudan University, Shanghai, China
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21
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Ming Sun S, Batté A, Elmer M, van der Horst SC, van Welsem T, Bean G, Ideker T, van Leeuwen F, van Attikum H. A genetic interaction map centered on cohesin reveals auxiliary factors involved in sister chromatid cohesion in S. cerevisiae. J Cell Sci 2020; 133:jcs237628. [PMID: 32299836 PMCID: PMC7325435 DOI: 10.1242/jcs.237628] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Accepted: 03/26/2020] [Indexed: 12/15/2022] Open
Abstract
Eukaryotic chromosomes are replicated in interphase and the two newly duplicated sister chromatids are held together by the cohesin complex and several cohesin auxiliary factors. Sister chromatid cohesion is essential for accurate chromosome segregation during mitosis, yet has also been implicated in other processes, including DNA damage repair, transcription and DNA replication. To assess how cohesin and associated factors functionally interconnect and coordinate with other cellular processes, we systematically mapped the genetic interactions of 17 cohesin genes centered on quantitative growth measurements of >52,000 gene pairs in the budding yeast Saccharomyces cerevisiae Integration of synthetic genetic interactions unveiled a cohesin functional map that constitutes 373 genetic interactions, revealing novel functional connections with post-replication repair, microtubule organization and protein folding. Accordingly, we show that the microtubule-associated protein Irc15 and the prefoldin complex members Gim3, Gim4 and Yke2 are new factors involved in sister chromatid cohesion. Our genetic interaction map thus provides a unique resource for further identification and functional interrogation of cohesin proteins. Since mutations in cohesin proteins have been associated with cohesinopathies and cancer, it may also help in identifying cohesin interactions relevant in disease etiology.
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Affiliation(s)
- Su Ming Sun
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, Netherlands
| | - Amandine Batté
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, Netherlands
| | - Mireille Elmer
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, Netherlands
- Electrical Engineering, Mathematics and Computer Science, Delft University of Technology, 2600 AA, Delft, Netherlands
| | - Sophie C van der Horst
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, Netherlands
| | - Tibor van Welsem
- Division of Gene Regulation, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
| | - Gordon Bean
- Bioinformatics and Systems Biology Program, University of California, San Diego; La Jolla, CA, 92093, USA
| | - Trey Ideker
- Bioinformatics and Systems Biology Program, University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Medicine, Division of Genetics, University of California, San Diego; La Jolla, CA, 92093, USA
- Department of Bioengineering, University of California, San Diego; La Jolla, CA, 92093, USA
- Cancer Cell Map Initiative (CCMI), Moores UCSD Cancer Center, La Jolla, CA, 92093, USA
| | - Fred van Leeuwen
- Division of Gene Regulation, Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, Netherlands
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, Netherlands
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22
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Minchell NE, Keszthelyi A, Baxter J. Cohesin Causes Replicative DNA Damage by Trapping DNA Topological Stress. Mol Cell 2020; 78:739-751.e8. [PMID: 32259483 PMCID: PMC7242899 DOI: 10.1016/j.molcel.2020.03.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 02/12/2020] [Accepted: 03/09/2020] [Indexed: 12/25/2022]
Abstract
DNA topological stress inhibits DNA replication fork (RF) progression and contributes to DNA replication stress. In Saccharomyces cerevisiae, we demonstrate that centromeric DNA and the rDNA array are especially vulnerable to DNA topological stress during replication. The activity of the SMC complexes cohesin and condensin are linked to both the generation and repair of DNA topological-stress-linked damage in these regions. At cohesin-enriched centromeres, cohesin activity causes the accumulation of DNA damage, RF rotation, and pre-catenation, confirming that cohesin-dependent DNA topological stress impacts on normal replication progression. In contrast, at the rDNA, cohesin and condensin activity inhibit the repair of damage caused by DNA topological stress. We propose that, as well as generally acting to ensure faithful genetic inheritance, SMCs can disrupt genome stability by trapping DNA topological stress.
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Affiliation(s)
- Nicola Elizabeth Minchell
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK
| | - Andrea Keszthelyi
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK
| | - Jonathan Baxter
- Genome Damage and Stability Centre, School of Life Sciences, Science Park Road, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, UK.
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23
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Benzi G, Camasses A, Atsunori Y, Katou Y, Shirahige K, Piatti S. A common molecular mechanism underlies the role of Mps1 in chromosome biorientation and the spindle assembly checkpoint. EMBO Rep 2020; 21:e50257. [PMID: 32307893 DOI: 10.15252/embr.202050257] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 03/02/2020] [Accepted: 03/17/2020] [Indexed: 01/27/2023] Open
Abstract
The Mps1 kinase corrects improper kinetochore-microtubule attachments, thereby ensuring chromosome biorientation. Yet, its critical phosphorylation targets in this process remain largely elusive. Mps1 also controls the spindle assembly checkpoint (SAC), which halts chromosome segregation until biorientation is attained. Its role in SAC activation is antagonised by the PP1 phosphatase and involves phosphorylation of the kinetochore scaffold Knl1/Spc105, which in turn recruits the Bub1 kinase to promote assembly of SAC effector complexes. A crucial question is whether error correction and SAC activation are part of a single or separable pathways. Here, we isolate and characterise a new yeast mutant, mps1-3, that is severely defective in chromosome biorientation and SAC signalling. Through an unbiased screen for extragenic suppressors, we found that mutations lowering PP1 levels at Spc105 or forced association of Bub1 with Spc105 reinstate both chromosome biorientation and SAC signalling in mps1-3 cells. Our data argue that a common mechanism based on Knl1/Spc105 phosphorylation is critical for Mps1 function in error correction and SAC signalling, thus supporting the idea that a single sensory apparatus simultaneously elicits both pathways.
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Affiliation(s)
- Giorgia Benzi
- CRBM, University of Montpellier, CNRS, Montpellier, France
| | - Alain Camasses
- IGMM, University of Montpellier, CNRS, Montpellier, France
| | - Yoshimura Atsunori
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan
| | - Yuki Katou
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan
| | - Katsuhiko Shirahige
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo, Japan
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24
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Mittal P, Ghule K, Trakroo D, Prajapati HK, Ghosh SK. Meiosis-Specific Functions of Kinesin Motors in Cohesin Removal and Maintenance of Chromosome Integrity in Budding Yeast. Mol Cell Biol 2020; 40:e00386-19. [PMID: 31964755 PMCID: PMC7108822 DOI: 10.1128/mcb.00386-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/20/2019] [Accepted: 12/26/2019] [Indexed: 12/31/2022] Open
Abstract
Kinesin motors provide the molecular forces at the kinetochore-microtubule interface and along the spindle to control chromosome segregation. During meiosis with two rounds of microtubule assembly-disassembly, the roles of motor proteins remain unexplored. We observed that in contrast to mitosis, Cin8 and Kip3 together are indispensable for meiosis. While examining meiosis in cin8Δ kip3Δ cells, we detected chromosome breakage in the meiosis II cells. The double mutant exhibits a delay in cohesin removal during anaphase I. Consequently, some cells fail to undergo meiosis II and form dyads, while some, as they progress through meiosis II, cause a defect in chromosome integrity. We believe that in the latter cells, an imbalance of spindle-mediated force and the simultaneous persistence of cohesin on chromosomes cause their breakage. We provide evidence that tension generated by Cin8 and Kip3 through microtubule cross-linking is essential for signaling efficient cohesin removal and the maintenance of chromosome integrity during meiosis.
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Affiliation(s)
- Priyanka Mittal
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Komal Ghule
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
| | - Deepika Trakroo
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
| | - Hemant Kumar Prajapati
- National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, USA
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai, India
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25
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Ugidos N, Mena J, Baquero S, Alloza I, Azkargorta M, Elortza F, Vandenbroeck K. Interactome of the Autoimmune Risk Protein ANKRD55. Front Immunol 2019; 10:2067. [PMID: 31620119 PMCID: PMC6759997 DOI: 10.3389/fimmu.2019.02067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 08/15/2019] [Indexed: 01/03/2023] Open
Abstract
The ankyrin repeat domain-55 (ANKRD55) gene contains intronic single nucleotide polymorphisms (SNPs) associated with risk to contract multiple sclerosis, rheumatoid arthritis or other autoimmune disorders. Risk alleles of these SNPs are associated with higher levels of ANKRD55 in CD4+ T cells. The biological function of ANKRD55 is unknown, but given that ankyrin repeat domains constitute one of the most common protein-protein interaction platforms in nature, it is likely to function in complex with other proteins. Thus, identification of its protein interactomes may provide clues. We identified ANKRD55 interactomes via recombinant overexpression in HEK293 or HeLa cells and mass spectrometry. One hundred forty-eight specifically interacting proteins were found in total protein extracts and 22 in extracts of sucrose gradient-purified nuclei. Bioinformatic analysis suggested that the ANKRD55-protein partners from total protein extracts were related to nucleotide and ATP binding, enriched in nuclear transport terms and associated with cell cycle and RNA, lipid and amino acid metabolism. The enrichment analysis of the ANKRD55-protein partners from nuclear extracts is related to sumoylation, RNA binding, processes associated with cell cycle, RNA transport, nucleotide and ATP binding. The interaction between overexpressed ANKRD55 isoform 001 and endogenous RPS3, the cohesins SMC1A and SMC3, CLTC, PRKDC, VIM, β-tubulin isoforms, and 14-3-3 isoforms were validated by western blot, reverse immunoprecipitaton and/or confocal microscopy. We also identified three phosphorylation sites in ANKRD55, with S436 exhibiting the highest score as likely 14-3-3 binding phosphosite. Our study suggests that ANKRD55 may exert function(s) in the formation or architecture of multiple protein complexes, and is regulated by (de)phosphorylation reactions. Based on interactome and subcellular localization analysis, ANKRD55 is likely transported into the nucleus by the classical nuclear import pathway and is involved in mitosis, probably via effects associated with mitotic spindle dynamics.
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Affiliation(s)
- Nerea Ugidos
- Neurogenomiks Group, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Jorge Mena
- Neurogenomiks Group, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Sara Baquero
- Neurogenomiks Group, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Iraide Alloza
- Neurogenomiks Group, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain
| | - Mikel Azkargorta
- Proteomics Platform, CIC bioGUNE, CIBERehd, ProteoRed-ISCIII, Derio, Spain
| | - Felix Elortza
- Proteomics Platform, CIC bioGUNE, CIBERehd, ProteoRed-ISCIII, Derio, Spain
| | - Koen Vandenbroeck
- Neurogenomiks Group, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Spain.,Achucarro Basque Center for Neuroscience, Leioa, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
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26
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Galander S, Barton RE, Kelly DA, Marston AL. Spo13 prevents premature cohesin cleavage during meiosis. Wellcome Open Res 2019; 4:29. [PMID: 30906881 PMCID: PMC6426077 DOI: 10.12688/wellcomeopenres.15066.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2019] [Indexed: 01/21/2024] Open
Abstract
Background: Meiosis produces gametes through two successive nuclear divisions, meiosis I and meiosis II. In contrast to mitosis and meiosis II, where sister chromatids are segregated, during meiosis I, homologous chromosomes are segregated. This requires the monopolar attachment of sister kinetochores and the loss of cohesion from chromosome arms, but not centromeres, during meiosis I. The establishment of both sister kinetochore mono-orientation and cohesion protection rely on the budding yeast meiosis I-specific Spo13 protein, the functional homolog of fission yeast Moa1 and mouse MEIKIN. Methods: Here we investigate the effects of loss of SPO13 on cohesion during meiosis I using a live-cell imaging approach. Results: Unlike wild type, cells lacking SPO13 fail to maintain the meiosis-specific cohesin subunit, Rec8, at centromeres and segregate sister chromatids to opposite poles during anaphase I. We show that the cohesin-destabilizing factor, Wpl1, is not primarily responsible for the loss of cohesion during meiosis I. Instead, premature loss of centromeric cohesin during anaphase I in spo13 Δ cells relies on separase-dependent cohesin cleavage. Further, cohesin loss in spo13 Δ anaphase I cells is blocked by forcibly tethering the regulatory subunit of protein phosphatase 2A, Rts1, to Rec8. Conclusions: Our findings indicate that separase-dependent cleavage of phosphorylated Rec8 causes premature cohesin loss in spo13 Δ cells.
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Affiliation(s)
- Stefan Galander
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Rachael E. Barton
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - David A. Kelly
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Adèle L. Marston
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
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27
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Galander S, Barton RE, Kelly DA, Marston AL. Spo13 prevents premature cohesin cleavage during meiosis. Wellcome Open Res 2019; 4:29. [PMID: 30906881 PMCID: PMC6426077 DOI: 10.12688/wellcomeopenres.15066.2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/06/2019] [Indexed: 01/11/2023] Open
Abstract
Background: Meiosis produces gametes through two successive nuclear divisions, meiosis I and meiosis II. In contrast to mitosis and meiosis II, where sister chromatids are segregated, during meiosis I, homologous chromosomes are segregated. This requires the monopolar attachment of sister kinetochores and the loss of cohesion from chromosome arms, but not centromeres, during meiosis I. The establishment of both sister kinetochore mono-orientation and cohesion protection rely on the budding yeast meiosis I-specific Spo13 protein, the functional homolog of fission yeast Moa1 and mouse MEIKIN. Methods: Here we investigate the effects of loss of
SPO13 on cohesion during meiosis I using a live-cell imaging approach. Results: Unlike wild type, cells lacking
SPO13 fail to maintain the meiosis-specific cohesin subunit, Rec8, at centromeres and segregate sister chromatids to opposite poles during anaphase I. We show that the cohesin-destabilizing factor, Wpl1, is not primarily responsible for the loss of cohesion during meiosis I. Instead, premature loss of centromeric cohesin during anaphase I in
spo13Δ cells relies on separase-dependent cohesin cleavage. Further, cohesin loss in
spo13Δ anaphase I cells is blocked by forcibly tethering the regulatory subunit of protein phosphatase 2A, Rts1, to Rec8. Conclusions: Our findings indicate that separase-dependent cleavage of phosphorylated Rec8 causes premature cohesin loss in
spo13Δ cells.
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Affiliation(s)
- Stefan Galander
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Rachael E Barton
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - David A Kelly
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Adèle L Marston
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3BF, UK
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28
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Mirkovic M, Oliveira RA. Centromeric Cohesin: Molecular Glue and Much More. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2019; 56:485-513. [PMID: 28840250 DOI: 10.1007/978-3-319-58592-5_20] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sister chromatid cohesion, mediated by the cohesin complex, is a prerequisite for faithful chromosome segregation during mitosis. Premature release of sister chromatid cohesion leads to random segregation of the genetic material and consequent aneuploidy. Multiple regulatory mechanisms ensure proper timing for cohesion establishment, concomitant with DNA replication, and cohesion release during the subsequent mitosis. Here we summarize the most important phases of the cohesin cycle and the coordination of cohesion release with the progression through mitosis. We further discuss recent evidence that has revealed additional functions for centromeric localization of cohesin in the fidelity of mitosis in metazoans. Beyond its well-established role as "molecular glue", centromeric cohesin complexes are now emerging as a scaffold for multiple fundamental processes during mitosis, including the formation of correct chromosome and kinetochore architecture, force balance with the mitotic spindle, and the association with key molecules that regulate mitotic fidelity, particularly at the chromosomal inner centromere. Centromeric chromatin may be thus seen as a dynamic place where cohesin ensures mitotic fidelity by multiple means.
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Affiliation(s)
- Mihailo Mirkovic
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 2780-156, Oeiras, Portugal
| | - Raquel A Oliveira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 2780-156, Oeiras, Portugal.
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29
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Estrem C, Moore JK. Astral microtubule forces alter nuclear organization and inhibit DNA repair in budding yeast. Mol Biol Cell 2019; 30:2000-2013. [PMID: 31067146 PMCID: PMC6727761 DOI: 10.1091/mbc.e18-12-0808] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Dividing cells must balance the maintenance of genome integrity with the generation of cytoskeletal forces that control chromosome position. In this study, we investigate how forces on astral microtubules impact the genome during cell division by using live-cell imaging of the cytoskeleton, chromatin, and DNA damage repair in budding yeast. Our results demonstrate that dynein-dependent forces on astral microtubules are propagated through the spindle during nuclear migration and when in excess can increase the frequency of double-stranded breaks (DSBs). Under these conditions, we find that homology-directed repair of DSBs is delayed, indicating antagonism between nuclear migration and the mechanism of homology-directed repair. These effects are partially rescued by mutants that weaken pericentric cohesion or mutants that decrease constriction on the nucleus as it moves through the bud neck. We propose that minimizing nuclear movement aids in finding a donor strand for homologous recombination.
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Affiliation(s)
- Cassi Estrem
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Jeffrey K Moore
- Department of Cell and Developmental Biology, University of Colorado School of Medicine, Aurora, CO 80045
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30
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García-Rodríguez LJ, Kasciukovic T, Denninger V, Tanaka TU. Aurora B-INCENP Localization at Centromeres/Inner Kinetochores Is Required for Chromosome Bi-orientation in Budding Yeast. Curr Biol 2019; 29:1536-1544.e4. [PMID: 31006569 PMCID: PMC6509284 DOI: 10.1016/j.cub.2019.03.051] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Revised: 03/06/2019] [Accepted: 03/22/2019] [Indexed: 12/24/2022]
Abstract
For proper chromosome segregation in mitosis, sister kinetochores must interact with microtubules from opposite spindle poles (chromosome bi-orientation) [1, 2]. To promote bi-orientation, Aurora B kinase disrupts aberrant kinetochore-microtubule interactions [3, 4, 5, 6]. It has long been debated how Aurora B halts this action when bi-orientation is established and tension is applied across sister kinetochores. A popular explanation for it is that, upon bi-orientation, sister kinetochores are pulled in opposite directions, stretching the outer kinetochores [7, 8] and moving Aurora B substrates away from Aurora-B-localizing sites at centromeres (spatial separation model) [3, 5, 9]. This model predicts that Aurora B localization at centromeres is required for bi-orientation. However, this notion was challenged by the observation that Bir1 (yeast survivin), which recruits Ipl1-Sli15 (yeast Aurora B-INCENP) to centromeres, can become dispensable for bi-orientation [10]. This raised the possibility that Aurora B localization at centromeres is dispensable for bi-orientation. Alternatively, there might be a Bir1-independent mechanism for recruiting Ipl1-Sli15 to centromeres or inner kinetochores [5, 9]. Here, we show that the COMA inner kinetochore sub-complex physically interacts with Sli15, recruits Ipl1-Sli15 to the inner kinetochore, and promotes chromosome bi-orientation, independently of Bir1, in budding yeast. Moreover, using an engineered recruitment of Ipl1-Sli15 to the inner kinetochore when both Bir1 and COMA are defective, we show that localization of Ipl1-Sli15 at centromeres or inner kinetochores is required for bi-orientation. Our results give important insight into how Aurora B disrupts kinetochore-microtubule interaction in a tension-dependent manner to promote chromosome bi-orientation. The COMA inner kinetochore sub-complex facilitates chromosome bi-orientation COMA physically interacts with Sli15 and recruits Ipl1-Sli15 to the inner kinetochore This function of COMA is independent of Bir1 and its role supporting robust cohesion Localizing Ipl1-Sli15 at centromeres/inner kinetochores is crucial for bi-orientation
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Affiliation(s)
- Luis J García-Rodríguez
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Taciana Kasciukovic
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Viola Denninger
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK.
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31
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Moura M, Conde C. Phosphatases in Mitosis: Roles and Regulation. Biomolecules 2019; 9:E55. [PMID: 30736436 PMCID: PMC6406801 DOI: 10.3390/biom9020055] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 02/07/2023] Open
Abstract
Mitosis requires extensive rearrangement of cellular architecture and of subcellular structures so that replicated chromosomes can bind correctly to spindle microtubules and segregate towards opposite poles. This process originates two new daughter nuclei with equal genetic content and relies on highly-dynamic and tightly regulated phosphorylation of numerous cell cycle proteins. A burst in protein phosphorylation orchestrated by several conserved kinases occurs as cells go into and progress through mitosis. The opposing dephosphorylation events are catalyzed by a small set of protein phosphatases, whose importance for the accuracy of mitosis is becoming increasingly appreciated. This review will focus on the established and emerging roles of mitotic phosphatases, describe their structural and biochemical properties, and discuss recent advances in understanding the regulation of phosphatase activity and function.
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Affiliation(s)
- Margarida Moura
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
- Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, 4050-313 Porto, Portugal.
| | - Carlos Conde
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal.
- i3S-Instituto de Investigação e Inovação em Saúde da Universidade do Porto, 4200-135, Porto, Portugal.
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32
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Lee HS, Lin Z, Chae S, Yoo YS, Kim BG, Lee Y, Johnson JL, Kim YS, Cantley LC, Lee CW, Yu H, Cho H. The chromatin remodeler RSF1 controls centromeric histone modifications to coordinate chromosome segregation. Nat Commun 2018; 9:3848. [PMID: 30242288 PMCID: PMC6155007 DOI: 10.1038/s41467-018-06377-w] [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] [Received: 03/06/2018] [Accepted: 08/20/2018] [Indexed: 01/20/2023] Open
Abstract
Chromatin remodelers regulate the nucleosome barrier during transcription, DNA replication, and DNA repair. The chromatin remodeler RSF1 is enriched at mitotic centromeres, but the functional consequences of this enrichment are not completely understood. Shugoshin (Sgo1) protects centromeric cohesion during mitosis and requires BuB1-dependent histone H2A phosphorylation (H2A-pT120) for localization. Loss of Sgo1 at centromeres causes chromosome missegregation. Here, we show that RSF1 regulates Sgo1 localization to centromeres through coordinating a crosstalk between histone acetylation and phosphorylation. RSF1 interacts with and recruits HDAC1 to centromeres, where it counteracts TIP60-mediated acetylation of H2A at K118. This deacetylation is required for the accumulation of H2A-pT120 and Sgo1 deposition, as H2A-K118 acetylation suppresses H2A-T120 phosphorylation by Bub1. Centromeric tethering of HDAC1 prevents premature chromatid separation in RSF1 knockout cells. Our results indicate that RSF1 regulates the dynamics of H2A histone modifications at mitotic centromeres and contributes to the maintenance of chromosome stability. The chromatin remodeler RSF1 is enriched at mitotic centromeres but its function there is poorly understood. Here, the authors show that RSF1 regulates H2A phosphorylation and acetylation at mitotic centromeres and contributes to chromosome stability.
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Affiliation(s)
- Ho-Soo Lee
- Department of Biochemistry, Ajou University School of Medicine, Suwon, 16499, Korea.,Genomic Instability Research Center, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Zhonghui Lin
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX, 75930, USA.,College of Chemistry, Fuzhou University, 350116, Fujian, China
| | - Sunyoung Chae
- Institute of Medical Science, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Young-Suk Yoo
- Department of Biochemistry, Ajou University School of Medicine, Suwon, 16499, Korea.,Genomic Instability Research Center, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Byung-Gyu Kim
- Center for Genomic Integrity, Institute for Basic Science, UNIST, Ulsan, 44919, Korea
| | - Youngsoo Lee
- Genomic Instability Research Center, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Jared L Johnson
- Meyer Cancer Center, Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - You-Sun Kim
- Department of Biochemistry, Ajou University School of Medicine, Suwon, 16499, Korea
| | - Lewis C Cantley
- Meyer Cancer Center, Department of Medicine, Weill Cornell Medical College, New York, NY, 10065, USA
| | - Chang-Woo Lee
- Department of Molecular Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Korea
| | - Hongtao Yu
- Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX, 75930, USA.
| | - Hyeseong Cho
- Department of Biochemistry, Ajou University School of Medicine, Suwon, 16499, Korea. .,Genomic Instability Research Center, Ajou University School of Medicine, Suwon, 16499, Korea.
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33
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Silva RD, Mirkovic M, Guilgur LG, Rathore OS, Martinho RG, Oliveira RA. Absence of the Spindle Assembly Checkpoint Restores Mitotic Fidelity upon Loss of Sister Chromatid Cohesion. Curr Biol 2018; 28:2837-2844.e3. [PMID: 30122528 PMCID: PMC6191932 DOI: 10.1016/j.cub.2018.06.062] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 05/30/2018] [Accepted: 06/22/2018] [Indexed: 12/28/2022]
Abstract
The fidelity of mitosis depends on cohesive forces that keep sister chromatids together. This is mediated by cohesin that embraces sister chromatid fibers from the time of their replication until the subsequent mitosis [1, 2, 3]. Cleavage of cohesin marks anaphase onset, where single chromatids are dragged to the poles by the mitotic spindle [4, 5, 6]. Cohesin cleavage should only occur when all chromosomes are properly bio-oriented to ensure equal genome distribution and prevent random chromosome segregation. Unscheduled loss of sister chromatid cohesion is prevented by a safeguard mechanism known as the spindle assembly checkpoint (SAC) [7, 8]. To identify specific conditions capable of restoring defects associated with cohesion loss, we screened for genes whose depletion modulates Drosophila wing development when sister chromatid cohesion is impaired. Cohesion deficiency was induced by knockdown of the acetyltransferase separation anxiety (San)/Naa50, a cohesin complex stabilizer [9, 10, 11, 12]. Several genes whose function impacts wing development upon cohesion loss were identified. Surprisingly, knockdown of key SAC proteins, Mad2 and Mps1, suppressed developmental defects associated with San depletion. SAC impairment upon cohesin removal, triggered by San depletion or artificial removal of the cohesin complex, prevented extensive genome shuffling, reduced segregation defects, and restored cell survival. This counterintuitive phenotypic suppression was caused by an intrinsic bias for efficient chromosome biorientation at mitotic entry, coupled with slow engagement of error-correction reactions. Thus, in contrast to SAC’s role as a safeguard mechanism for mitotic fidelity, removal of this checkpoint alleviates mitotic errors when sister chromatid cohesion is compromised. A Drosophila screen identifies SAC genes as suppressors of cohesion-related defects SAC removal enhances mitotic fidelity upon premature cohesion loss SAC inactivation enhances cell survival and tissue homeostasis upon cohesion loss
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Affiliation(s)
- Rui D Silva
- Departamento de Ciências Biomédicas e Medicina and Center for Biomedical Research, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Mihailo Mirkovic
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Leonardo G Guilgur
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal
| | - Om S Rathore
- Departamento de Ciências Biomédicas e Medicina and Center for Biomedical Research, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal
| | - Rui Gonçalo Martinho
- Departamento de Ciências Biomédicas e Medicina and Center for Biomedical Research, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro, Portugal; Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, 1649-028 Lisboa, Portugal; Institute of Biomedicine-iBiMED and Department of Medical Sciences, University of Aveiro, Campus Universitario de Santiago, Agra do Crasto-Ed. 30, 3810-193 Aveiro, Portugal.
| | - Raquel A Oliveira
- Instituto Gulbenkian de Ciência, Rua da Quinta Grande, 6, 2780-156 Oeiras, Portugal.
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34
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Carvalhal S, Tavares A, Santos MB, Mirkovic M, Oliveira RA. A quantitative analysis of cohesin decay in mitotic fidelity. J Cell Biol 2018; 217:3343-3353. [PMID: 30002073 PMCID: PMC6168270 DOI: 10.1083/jcb.201801111] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 06/05/2018] [Accepted: 06/28/2018] [Indexed: 12/29/2022] Open
Abstract
Sister chromatid cohesion mediated by cohesin is essential for mitotic fidelity. It counteracts spindle forces to prevent premature chromatid individualization and random genome segregation. However, it is unclear what effects a partial decline of cohesin may have on chromosome organization. In this study, we provide a quantitative analysis of cohesin decay by inducing acute removal of defined amounts of cohesin from metaphase-arrested chromosomes. We demonstrate that sister chromatid cohesion is very resistant to cohesin loss as chromatid disjunction is only observed when chromosomes lose >80% of bound cohesin. Removal close to this threshold leads to chromosomes that are still cohered but display compromised chromosome alignment and unstable spindle attachments. Partial cohesin decay leads to increased duration of mitosis and susceptibility to errors in chromosome segregation. We propose that high cohesin density ensures centromeric chromatin rigidity necessary to maintain a force balance with the mitotic spindle. Partial cohesin loss may lead to chromosome segregation errors even when sister chromatid cohesion is fulfilled.
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Bourmoum M, Charles R, Claing A. ARF6 protects sister chromatid cohesion to ensure the formation of stable kinetochore-microtubule attachments. J Cell Sci 2018; 131:jcs216598. [PMID: 29724911 DOI: 10.1242/jcs.216598] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 04/25/2018] [Indexed: 01/02/2023] Open
Abstract
Sister chromatid cohesion, facilitated by the cohesin protein complex, is crucial for the establishment of stable bipolar attachments of chromosomes to the spindle microtubules and their faithful segregation. Here, we demonstrate that the GTPase ARF6 prevents the premature loss of sister chromatid cohesion. During mitosis, ARF6-depleted cells normally completed chromosome congression. However, at the metaphase plate, chromosomes failed to establish stable kinetochore-microtubule attachments because of the impaired cohesion at centromeres. As a result, the spindle assembly checkpoint (SAC) was active and cyclin B ubiquitylation and degradation were blocked. Chromosomes and/or chromatids in these cells scattered gradually from the metaphase plate to the two poles of the cell or remained blocked at the metaphase plate for hours. Our study demonstrates that the small GTP-binding protein ARF6 is essential for maintaining centromeric cohesion between sister chromatids, which is necessary for the establishment of stable k-fibres, SAC satisfaction and the onset of anaphase.
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Affiliation(s)
- Mohamed Bourmoum
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, C.P. 6128 Succursale Centre-ville, Montreal, Quebec, Canada, H3T 1J4
| | - Ricardo Charles
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, C.P. 6128 Succursale Centre-ville, Montreal, Quebec, Canada, H3T 1J4
| | - Audrey Claing
- Department of Pharmacology and Physiology, Faculty of Medicine, Université de Montréal, C.P. 6128 Succursale Centre-ville, Montreal, Quebec, Canada, H3T 1J4
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Augustine B, Chin CF, Yeong FM. Role of Kip2 during early mitosis - impact on spindle pole body separation and chromosome capture. J Cell Sci 2018; 131:jcs.211425. [PMID: 29739877 DOI: 10.1242/jcs.211425] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 04/30/2018] [Indexed: 11/20/2022] Open
Abstract
Mitotic spindle dynamics are regulated during the cell cycle by microtubule motor proteins. In Saccharomyces cerevisiae, one such protein is Kip2p, a plus-end motor that regulates the polymerization and stability of cytoplasmic microtubules (cMTs). Kip2p levels are regulated during the cell cycle, and its overexpression leads to the formation of hyper-elongated cMTs. To investigate the significance of varying Kip2p levels during the cell cycle and the hyper-elongated cMTs, we overexpressed KIP2 in the G1 phase and examined the effects on the separation of spindle pole bodies (SPBs) and chromosome segregation. Our results show that failure to regulate the cMT lengths during G1-S phase prevents the separation of SPBs. This, in turn, affects chromosome capture and leads to the activation of spindle assembly checkpoint (SAC) and causes mitotic arrest. These defects could be rescued by either the inactivation of checkpoint components or by co-overexpression of CIN8, which encodes a motor protein that elongates inter-polar microtubules (ipMTs). Hence, we propose that the maintenance of Kip2p level and cMT lengths during early cell division is important to ensure coordination between SPB separation and chromosome capture by kinetochore microtubules (kMTs).
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Affiliation(s)
- Beryl Augustine
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, MD4, 5 Science Drive 2, Singapore 117545
| | - Cheen Fei Chin
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, MD4, 5 Science Drive 2, Singapore 117545
| | - Foong May Yeong
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, MD4, 5 Science Drive 2, Singapore 117545
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Xu T, Ma M, Dai J, Yu S, Wu X, Tang H, Yu J, Yan J, Yu H, Chi Z, Si L, Sheng X, Cui C, Kong Y, Guo J. Gene expression screening identifies CDCA5 as a potential therapeutic target in acral melanoma. Hum Pathol 2018; 75:137-145. [DOI: 10.1016/j.humpath.2018.02.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 02/01/2018] [Accepted: 02/02/2018] [Indexed: 02/05/2023]
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Lianga N, Doré C, Kennedy EK, Yeh E, Williams EC, Fortinez CM, Wang A, Bloom KS, Rudner AD. Cdk1 phosphorylation of Esp1/Separase functions with PP2A and Slk19 to regulate pericentric Cohesin and anaphase onset. PLoS Genet 2018; 14:e1007029. [PMID: 29561844 PMCID: PMC5880407 DOI: 10.1371/journal.pgen.1007029] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 04/02/2018] [Accepted: 09/17/2017] [Indexed: 12/27/2022] Open
Abstract
Anaphase onset is an irreversible cell cycle transition that is triggered by the activation of the protease Separase. Separase cleaves the Mcd1 (also known as Scc1) subunit of Cohesin, a complex of proteins that physically links sister chromatids, triggering sister chromatid separation. Separase is regulated by the degradation of the anaphase inhibitor Securin which liberates Separase from inhibitory Securin/Separase complexes. In many organisms, Securin is not essential suggesting that Separase is regulated by additional mechanisms. In this work, we show that in budding yeast Cdk1 activates Separase (Esp1 in yeast) through phosphorylation to trigger anaphase onset. Esp1 activation is opposed by protein phosphatase 2A associated with its regulatory subunit Cdc55 (PP2ACdc55) and the spindle protein Slk19. Premature anaphase spindle elongation occurs when Securin (Pds1 in yeast) is inducibly degraded in cells that also contain phospho-mimetic mutations in ESP1, or deletion of CDC55 or SLK19. This striking phenotype is accompanied by advanced degradation of Mcd1, disruption of pericentric Cohesin organization and chromosome mis-segregation. Our findings suggest that PP2ACdc55 and Slk19 function redundantly with Pds1 to inhibit Esp1 within pericentric chromatin, and both Pds1 degradation and Cdk1-dependent phosphorylation of Esp1 act together to trigger anaphase onset.
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Affiliation(s)
- Noel Lianga
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Carole Doré
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Erin K. Kennedy
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Elaine Yeh
- University of North Carolina, Chapel Hill, Department of Biology, Chapel Hill, NC, United States of America
| | - Elizabeth C. Williams
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Camille Marie Fortinez
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Alick Wang
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Kerry S. Bloom
- University of North Carolina, Chapel Hill, Department of Biology, Chapel Hill, NC, United States of America
| | - Adam D. Rudner
- Ottawa Institute of Systems Biology and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
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Differential abundance and transcription of 14-3-3 proteins during vegetative growth and sexual reproduction in budding yeast. Sci Rep 2018; 8:2145. [PMID: 29391437 PMCID: PMC5794856 DOI: 10.1038/s41598-018-20284-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/16/2018] [Indexed: 12/02/2022] Open
Abstract
14-3-3 is a family of relatively low molecular weight, acidic, dimeric proteins, conserved from yeast to metazoans including humans. Apart from their role in diverse cellular processes, these proteins are also known for their role in several clinical implications. Present proteomic and biochemical comparison showed increased abundance and differential phosphorylation of these proteins in meiotic cells. Double deletion of bmh1−/−bmh2−/− leads to complete absence of sporulation with cells arrested at G1/S phase while further incubation of cells in sporulating media leads to cell death. In silico analysis showed the presence of 14-3-3 interacting motifs in bonafide members of kinetochore complex (KC) and spindle pole body (SPB), while present cell biological data pointed towards the possible role of yeast Bmh1/2 in regulating the behaviour of KC and SPB. We further showed the involvement of 14-3-3 in segregation of genetic material and expression of human 14-3-3β/α was able to complement the function of endogenous 14-3-3 protein even in the complex cellular process like meiosis. Our present data also established haplosufficient nature of BMH1/2. We further showed that proteins synthesized during mitotic growth enter meiotic cells without de novo synthesis except for meiotic-specific proteins required for induction and meiotic progression in Saccharomyces cerevisiae.
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Eeftens J, Dekker C. Catching DNA with hoops—biophysical approaches to clarify the mechanism of SMC proteins. Nat Struct Mol Biol 2017; 24:1012-1020. [DOI: 10.1038/nsmb.3507] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/18/2017] [Indexed: 12/11/2022]
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Hinshaw SM, Makrantoni V, Harrison SC, Marston AL. The Kinetochore Receptor for the Cohesin Loading Complex. Cell 2017; 171:72-84.e13. [PMID: 28938124 PMCID: PMC5610175 DOI: 10.1016/j.cell.2017.08.017] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2017] [Revised: 05/03/2017] [Accepted: 08/09/2017] [Indexed: 12/29/2022]
Abstract
The ring-shaped cohesin complex brings together distant DNA domains to maintain, express, and segregate the genome. Establishing specific chromosomal linkages depends on cohesin recruitment to defined loci. One such locus is the budding yeast centromere, which is a paradigm for targeted cohesin loading. The kinetochore, a multiprotein complex that connects centromeres to microtubules, drives the recruitment of high levels of cohesin to link sister chromatids together. We have exploited this system to determine the mechanism of specific cohesin recruitment. We show that phosphorylation of the Ctf19 kinetochore protein by a conserved kinase, DDK, provides a binding site for the Scc2/4 cohesin loading complex, thereby directing cohesin loading to centromeres. A similar mechanism targets cohesin to chromosomes in vertebrates. These findings represent a complete molecular description of targeted cohesin loading, a phenomenon with wide-ranging importance in chromosome segregation and, in multicellular organisms, transcription regulation.
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Affiliation(s)
- Stephen M Hinshaw
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Vasso Makrantoni
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| | - Adèle L Marston
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK.
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Daniloski Z, Smith S. Loss of Tumor Suppressor STAG2 Promotes Telomere Recombination and Extends the Replicative Lifespan of Normal Human Cells. Cancer Res 2017; 77:5530-5542. [PMID: 28819029 DOI: 10.1158/0008-5472.can-17-1260] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 07/11/2017] [Accepted: 08/08/2017] [Indexed: 01/19/2023]
Abstract
Sister chromatids are held together by cohesin, a tripartite ring with a peripheral SA1/2 subunit, where SA1 is required for telomere cohesion and SA2 for centromere cohesion. The STAG2 gene encoding SA2 is often inactivated in human cancer, but not in in a manner associated with aneuploidy. Thus, how these tumors maintain chromosomal cohesion and how STAG2 loss contributes to tumorigenesis remain open questions. Here we show that, despite a loss in centromere cohesion, sister chromatids in STAG2 mutant tumor cells maintain cohesion in mitosis at chromosome arms and telomeres. Telomere maintenance in STAG2 mutant tumor cells occurred by either telomere recombination or telomerase activation mechanisms. Notably, these cells were refractory to telomerase inhibitors, indicating recombination can provide an alternative means of telomere maintenance. STAG2 silencing in normal human cells that lack telomerase led to increased recombination at telomeres, delayed telomere shortening, and postponed senescence onset. Insofar as telomere shortening and replicative senescence prevent genomic instability and cancer by limiting the number of cell divisions, our findings suggest that extending the lifespan of normal human cells due to inactivation of STAG2 could promote tumorigenesis by extending the period during which tumor-driving mutations occur. Cancer Res; 77(20); 5530-42. ©2017 AACR.
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Affiliation(s)
- Zharko Daniloski
- Department of Pathology, Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, New York
| | - Susan Smith
- Department of Pathology, Kimmel Center for Biology and Medicine at the Skirball Institute, New York University School of Medicine, New York, New York.
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43
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Schalch T, Steiner FA. Structure of centromere chromatin: from nucleosome to chromosomal architecture. Chromosoma 2017; 126:443-455. [PMID: 27858158 PMCID: PMC5509776 DOI: 10.1007/s00412-016-0620-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 12/14/2022]
Abstract
The centromere is essential for the segregation of chromosomes, as it serves as attachment site for microtubules to mediate chromosome segregation during mitosis and meiosis. In most organisms, the centromere is restricted to one chromosomal region that appears as primary constriction on the condensed chromosome and is partitioned into two chromatin domains: The centromere core is characterized by the centromere-specific histone H3 variant CENP-A (also called cenH3) and is required for specifying the centromere and for building the kinetochore complex during mitosis. This core region is generally flanked by pericentric heterochromatin, characterized by nucleosomes containing H3 methylated on lysine 9 (H3K9me) that are bound by heterochromatin proteins. During mitosis, these two domains together form a three-dimensional structure that exposes CENP-A-containing chromatin to the surface for interaction with the kinetochore and microtubules. At the same time, this structure supports the tension generated during the segregation of sister chromatids to opposite poles. In this review, we discuss recent insight into the characteristics of the centromere, from the specialized chromatin structures at the centromere core and the pericentromere to the three-dimensional organization of these regions that make up the functional centromere.
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Affiliation(s)
- Thomas Schalch
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
| | - Florian A Steiner
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
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44
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Yue Z, Komoto S, Gierlinski M, Pasquali D, Kitamura E, Tanaka TU. Mechanisms mitigating problems associated with multiple kinetochores on one microtubule in early mitosis. J Cell Sci 2017; 130:2266-2276. [PMID: 28546446 PMCID: PMC5536920 DOI: 10.1242/jcs.203000] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 05/22/2017] [Indexed: 12/02/2022] Open
Abstract
Proper chromosome segregation in mitosis relies on correct kinetochore interaction with spindle microtubules. In early mitosis, each kinetochore usually interacts with the lateral side of each microtubule and is subsequently tethered at the microtubule end. However, since eukaryotic cells carry multiple chromosomes, multiple kinetochores could occasionally interact with a single microtubule. The consequence of this is unknown. Here, we find that, although two kinetochores (two pairs of sister kinetochores) can interact with the lateral side of one microtubule, only one kinetochore can form a sustained attachment to the microtubule end in budding yeast (Saccharomyces cerevisiae). This leads to detachment of the other kinetochore from the microtubule end (or a location in its proximity). Intriguingly, in this context, kinetochore sliding along a microtubule towards a spindle pole delays and diminishes discernible kinetochore detachment. This effect expedites collection of the entire set of kinetochores to a spindle pole. We propose that cells are equipped with the kinetochore-sliding mechanism to mitigate problems associated with multiple kinetochores on one microtubule in early mitosis. Summary: Given that eukaryotic cells carry multiple chromosomes, multiple kinetochores could occasionally interact with a single microtubule. We identify problems associated with this situation and find mechanisms mitigating these problems.
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Affiliation(s)
- Zuojun Yue
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Shinya Komoto
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Marek Gierlinski
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.,Data Analysis Group, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Debora Pasquali
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Etsushi Kitamura
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, UK
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Vasileva V, Gierlinski M, Yue Z, O'Reilly N, Kitamura E, Tanaka TU. Molecular mechanisms facilitating the initial kinetochore encounter with spindle microtubules. J Cell Biol 2017; 216:1609-1622. [PMID: 28446512 PMCID: PMC5461016 DOI: 10.1083/jcb.201608122] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 02/15/2017] [Accepted: 04/03/2017] [Indexed: 12/11/2022] Open
Abstract
The initial kinetochore (KT) encounter with a spindle microtubule (MT) is one of the rate-limiting steps in establishing proper KT–MT interaction during mitosis. This study reveals how multiple factors cooperate to facilitate the KT encounter with a spindle MT. In particular, it highlights the important roles of KT-derived MTs in this process. The initial kinetochore (KT) encounter with a spindle microtubule (MT; KT capture) is one of the rate-limiting steps in establishing proper KT–MT interaction during mitosis. KT capture is facilitated by multiple factors, such as MT extension in various directions, KT diffusion, and MT pivoting. In addition, KTs generate short MTs, which subsequently interact with a spindle MT. KT-derived MTs may facilitate KT capture, but their contribution is elusive. In this study, we find that Stu1 recruits Stu2 to budding yeast KTs, which promotes MT generation there. By removing Stu2 specifically from KTs, we show that KT-derived MTs shorten the half-life of noncaptured KTs from 48–49 s to 28–34 s. Using computational simulation, we found that multiple factors facilitate KT capture redundantly or synergistically. In particular, KT-derived MTs play important roles both by making a significant contribution on their own and by synergistically enhancing the effects of KT diffusion and MT pivoting. Our study reveals fundamental mechanisms facilitating the initial KT encounter with spindle MTs.
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Affiliation(s)
- Vanya Vasileva
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Marek Gierlinski
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK.,Data Analysis Group, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Zuojun Yue
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Nicola O'Reilly
- Lincoln's Inn Fields Laboratory, The Francis Crick Institute, London WC2A 3LY, England, UK
| | - Etsushi Kitamura
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Tomoyuki U Tanaka
- Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
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Gligoris T, Löwe J. Structural Insights into Ring Formation of Cohesin and Related Smc Complexes. Trends Cell Biol 2016; 26:680-693. [PMID: 27134029 PMCID: PMC4989898 DOI: 10.1016/j.tcb.2016.04.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 03/30/2016] [Accepted: 04/05/2016] [Indexed: 12/14/2022]
Abstract
Cohesin facilitates sister chromatid cohesion through the formation of a large ring structure that encircles DNA. Its function relies on two structural maintenance of chromosomes (Smc) proteins, which are found in almost all organisms tested, from bacteria to humans. In accordance with their ubiquity, Smc complexes, such as cohesin, condensin, Smc5-6, and the dosage compensation complex, affect almost all processes of DNA homeostasis. Although their precise molecular mechanism remains enigmatic, here we provide an overview of the architecture of eukaryotic Smc complexes with a particular focus on cohesin, which has seen the most progress recently. Given the evident conservation of many structural features between Smc complexes, it is expected that architecture and topology will have a significant role when deciphering their precise molecular mechanisms.
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Affiliation(s)
- Thomas Gligoris
- Department of Biochemistry, University of Oxford, Oxford, OX1 3QU, UK.
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
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Agircan FG, Hata S, Nussbaum-Krammer C, Atorino E, Schiebel E. Proximity mapping of human separase by the BioID approach. Biochem Biophys Res Commun 2016; 478:656-62. [PMID: 27495871 DOI: 10.1016/j.bbrc.2016.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 07/26/2016] [Accepted: 08/01/2016] [Indexed: 01/26/2023]
Abstract
Separase is a caspase-like cysteine protease that is best known for its essential role during the metaphase-to-anaphase transition when it cleaves the cohesin ring complex that keeps the sister chromatids together. Another important function of separase is to regulate the process of centriole separation, known as centriole disengagement, at the end of mitosis. We used proximity-dependent biotin identification (BioID) to expand our knowledge on the identity of separase's proximity interactors. We show that separase BioID labeled two domains at the mother centriole: an area underneath the centriolar appendages and another at the proximal end of the mother centriole. BioID analysis identified more than 200 proximity interactors of separase, one being the Alström Syndrome Protein 1 (ALMS1) at the base of centrioles. Other proximity interactors are the histone chaperons NAP1L1 and NAP1L4, which localize to the spindle poles during mitosis and the spindle assembly checkpoint proteins BUBR1, SKA1 and SKA3 that reside at kinetochores in early mitosis. Finally, we show that depletion of BUBR1 homolog from Caenorhabditis elegans delayed the recruitment of separase to mitotic chromosomes, and eventually anaphase onset.
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Affiliation(s)
- Fikret Gurkan Agircan
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Shoji Hata
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Carmen Nussbaum-Krammer
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Enrico Atorino
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany
| | - Elmar Schiebel
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH Allianz, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
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48
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Takeda S, Hoa NN, Sasanuma H. The role of the Mre11-Rad50-Nbs1 complex in double-strand break repair-facts and myths. JOURNAL OF RADIATION RESEARCH 2016; 57 Suppl 1:i25-i32. [PMID: 27311583 PMCID: PMC4990115 DOI: 10.1093/jrr/rrw034] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 02/16/2016] [Accepted: 02/23/2016] [Indexed: 06/06/2023]
Abstract
Homologous recombination (HR) initiates double-strand break (DSB) repair by digesting 5'-termini at DSBs, the biochemical reaction called DSB resection, during which DSBs are processed by nucleases to generate 3' single-strand DNA. Rad51 recombinase polymerizes along resected DNA, and the resulting Rad51-DNA complex undergoes homology search. Although DSB resection by the Mre11 nuclease plays a critical role in HR in Saccharomyces cerevisiae, it remains elusive whether DSB resection by Mre11 significantly contributes to HR-dependent DSB repair in mammalian cells. Depletion of Mre11 decreases the efficiency of DSB resection only by 2- to 3-fold in mammalian cells. We show that although Mre11 is required for efficient HR-dependent repair of ionizing-radiation-induced DSBs, Mre11 is largely dispensable for DSB resection in both chicken DT40 and human TK6 B cell lines. Moreover, a 2- to 3-fold decrease in DSB resection has virtually no impact on the efficiency of HR. Thus, although a large number of researchers have reported the vital role of Mre11-mediated DSB resection in HR, the role may not explain the very severe defect in HR in Mre11-deficient cells, including their lethality. We here show experimental evidence for the additional roles of Mre11 in (i) elimination of chemical adducts from DSB ends for subsequent DSB repair, and (ii) maintaining HR intermediates for their proper resolution.
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Affiliation(s)
- Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Nguyen Ngoc Hoa
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroyuki Sasanuma
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida Konoe, Sakyo-ku, Kyoto 606-8501, Japan
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Abstract
SMC (structural maintenance of chromosomes) complexes - which include condensin, cohesin and the SMC5-SMC6 complex - are major components of chromosomes in all living organisms, from bacteria to humans. These ring-shaped protein machines, which are powered by ATP hydrolysis, topologically encircle DNA. With their ability to hold more than one strand of DNA together, SMC complexes control a plethora of chromosomal activities. Notable among these are chromosome condensation and sister chromatid cohesion. Moreover, SMC complexes have an important role in DNA repair. Recent mechanistic insight into the function and regulation of these universal chromosomal machines enables us to propose molecular models of chromosome structure, dynamics and function, illuminating one of the fundamental entities in biology.
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50
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Cairo L, Wozniak R. The Nuclear Transport Factor Kap121 Is Required for Stability of the Dam1 Complex and Mitotic Kinetochore Bi-orientation. Cell Rep 2016; 14:2440-50. [DOI: 10.1016/j.celrep.2016.02.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Revised: 11/04/2015] [Accepted: 02/04/2016] [Indexed: 12/30/2022] Open
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