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Cai J, Yun Q, Zhang CY, Wang Z, Hinshaw SM, Zhou H, Suhandynata RT. Concatemer Assisted Stoichiometry Analysis (CASA): targeted mass spectrometry for protein quantification. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.26.605382. [PMID: 39091769 PMCID: PMC11291133 DOI: 10.1101/2024.07.26.605382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 08/04/2024]
Abstract
Large multi-protein machines are central to multiple biological processes. However, stoichiometric determination of protein complex subunits in their native states presents a significant challenge. This study addresses the limitations of current tools in accuracy and precision by introducing concatemer-assisted stoichiometry analysis (CASA). CASA leverages stable isotope-labeled concatemers and liquid chromatography parallel reaction monitoring mass spectrometry (LC-PRM-MS) to achieve robust quantification of proteins with sub-femtomole sensitivity. As a proof-of-concept, CASA was applied to study budding yeast kinetochores. Stoichiometries were determined for ex vivo reconstituted kinetochore components, including the canonical H3 nucleosomes, centromeric (Cse4CENP-A) nucleosomes, centromere proximal factors (Cbf1 and CBF3 complex), inner kinetochore proteins (Mif2CENP-C, Ctf19CCAN complex), and outer kinetochore proteins (KMN network). Absolute quantification by CASA revealed Cse4CENP-A as a cell-cycle controlled limiting factor for kinetochore assembly. These findings demonstrate that CASA is applicable for stoichiometry analysis of multi-protein assemblies.
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Affiliation(s)
- Jiaxi Cai
- Department of Cellular and Molecular Medicine, University of California, San Diego, California
- Department of Bioengineering, University of California, San Diego, California
| | - Quan Yun
- Department of Cellular and Molecular Medicine, University of California, San Diego, California
| | - Cindy Yuxuan Zhang
- Department of Cellular and Molecular Medicine, University of California, San Diego, California
| | - Ziyi Wang
- Department of Cellular and Molecular Medicine, University of California, San Diego, California
| | - Stephen M. Hinshaw
- Department of Chemical and Systems Biology, Stanford University, Palo Alto, California
| | - Huilin Zhou
- Department of Cellular and Molecular Medicine, University of California, San Diego, California
- Department of Bioengineering, University of California, San Diego, California
- Moores Cancer Center, University of California, San Diego, California
| | - Raymond T. Suhandynata
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, California
- Department of Pathology, University of California, San Diego, California
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2
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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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3
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Ballmer D, Akiyoshi B. Dynamic localization of the chromosomal passenger complex in trypanosomes is controlled by the orphan kinesins KIN-A and KIN-B. eLife 2024; 13:RP93522. [PMID: 38564240 PMCID: PMC10987093 DOI: 10.7554/elife.93522] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024] Open
Abstract
The chromosomal passenger complex (CPC) is an important regulator of cell division, which shows dynamic subcellular localization throughout mitosis, including kinetochores and the spindle midzone. In traditional model eukaryotes such as yeasts and humans, the CPC consists of the catalytic subunit Aurora B kinase, its activator INCENP, and the localization module proteins Borealin and Survivin. Intriguingly, Aurora B and INCENP as well as their localization pattern are conserved in kinetoplastids, an evolutionarily divergent group of eukaryotes that possess unique kinetochore proteins and lack homologs of Borealin or Survivin. It is not understood how the kinetoplastid CPC assembles nor how it is targeted to its subcellular destinations during the cell cycle. Here, we identify two orphan kinesins, KIN-A and KIN-B, as bona fide CPC proteins in Trypanosoma brucei, the kinetoplastid parasite that causes African sleeping sickness. KIN-A and KIN-B form a scaffold for the assembly of the remaining CPC subunits. We show that the C-terminal unstructured tail of KIN-A interacts with the KKT8 complex at kinetochores, while its N-terminal motor domain promotes CPC translocation to spindle microtubules. Thus, the KIN-A:KIN-B complex constitutes a unique 'two-in-one' CPC localization module, which directs the CPC to kinetochores from S phase until metaphase and to the central spindle in anaphase. Our findings highlight the evolutionary diversity of CPC proteins and raise the possibility that kinesins may have served as the original transport vehicles for Aurora kinases in early eukaryotes.
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Affiliation(s)
- Daniel Ballmer
- Department of Biochemistry, University of OxfordOxfordUnited Kingdom
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological SciencesEdinburghUnited Kingdom
| | - Bungo Akiyoshi
- Department of Biochemistry, University of OxfordOxfordUnited Kingdom
- The Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological SciencesEdinburghUnited Kingdom
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4
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Popchock AR, Larson JD, Dubrulle J, Asbury CL, Biggins S. Direct observation of coordinated assembly of individual native centromeric nucleosomes. EMBO J 2023; 42:e114534. [PMID: 37469281 PMCID: PMC10476280 DOI: 10.15252/embj.2023114534] [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: 05/16/2023] [Revised: 06/27/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
Eukaryotic chromosome segregation requires the kinetochore, a megadalton-sized machine that forms on specialized centromeric chromatin containing CENP-A, a histone H3 variant. CENP-A deposition requires a chaperone protein HJURP that targets it to the centromere, but it has remained unclear whether HJURP has additional functions beyond CENP-A targeting and why high AT DNA content, which disfavors nucleosome assembly, is widely conserved at centromeres. To overcome the difficulties of studying nucleosome formation in vivo, we developed a microscopy assay that enables direct observation of de novo centromeric nucleosome recruitment and maintenance with single molecule resolution. Using this assay, we discover that CENP-A can arrive at centromeres without its dedicated centromere-specific chaperone HJURP, but stable incorporation depends on HJURP and additional DNA-binding proteins of the inner kinetochore. We also show that homopolymer AT runs in the yeast centromeres are essential for efficient CENP-A deposition. Together, our findings reveal requirements for stable nucleosome formation and provide a foundation for further studies of the assembly and dynamics of native kinetochore complexes.
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Affiliation(s)
- Andrew R Popchock
- Basic Sciences Division, Howard Hughes Medical InstituteFred Hutchinson Cancer CenterSeattleWAUSA
| | - Joshua D Larson
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | | | - Charles L Asbury
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | - Sue Biggins
- Basic Sciences Division, Howard Hughes Medical InstituteFred Hutchinson Cancer CenterSeattleWAUSA
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5
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Popchock AR, Larson JD, Dubrulle J, Asbury CL, Biggins S. Direct observation of coordinated assembly of individual native centromeric nucleosomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524981. [PMID: 36711558 PMCID: PMC9882320 DOI: 10.1101/2023.01.20.524981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Eukaryotic chromosome segregation requires the kinetochore, a megadalton-sized machine that forms on specialized centromeric chromatin containing CENP-A, a histone H3 variant. CENP-A deposition requires a chaperone protein HJURP that targets it to the centromere, but it has remained unclear whether HJURP has additional functions beyond CENP-A targeting and why high AT DNA content, which disfavors nucleosome assembly, is widely conserved at centromeres. To overcome the difficulties of studying nucleosome formation in vivo, we developed a microscopy assay that enables direct observation of de novo centromeric nucleosome recruitment and maintenance with single molecule resolution. Using this assay, we discover that CENP-A can arrive at centromeres without its dedicated centromere-specific chaperone HJURP, but stable incorporation depends on HJURP and additional DNA-binding proteins of the inner kinetochore. We also show that homopolymer AT runs in the yeast centromeres are essential for efficient CENP-A deposition. Together, our findings reveal requirements for stable nucleosome formation and provide a foundation for further studies of the assembly and dynamics of native kinetochore complexes.
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Affiliation(s)
- Andrew R. Popchock
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Joshua D. Larson
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA
| | - Julien Dubrulle
- Shared Resources, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Charles L. Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
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6
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Haase MAB, Ólafsson G, Flores RL, Boakye‐Ansah E, Zelter A, Dickinson MS, Lazar‐Stefanita L, Truong DM, Asbury CL, Davis TN, Boeke JD. DASH/Dam1 complex mutants stabilize ploidy in histone-humanized yeast by weakening kinetochore-microtubule attachments. EMBO J 2023; 42:e112600. [PMID: 36651597 PMCID: PMC10106983 DOI: 10.15252/embj.2022112600] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/16/2022] [Accepted: 12/20/2022] [Indexed: 01/19/2023] Open
Abstract
Forcing budding yeast to chromatinize their DNA with human histones manifests an abrupt fitness cost. We previously proposed chromosomal aneuploidy and missense mutations as two potential modes of adaptation to histone humanization. Here, we show that aneuploidy in histone-humanized yeasts is specific to a subset of chromosomes that are defined by their centromeric evolutionary origins but that these aneuploidies are not adaptive. Instead, we find that a set of missense mutations in outer kinetochore proteins drives adaptation to human histones. Furthermore, we characterize the molecular mechanism underlying adaptation in two mutants of the outer kinetochore DASH/Dam1 complex, which reduce aneuploidy by suppression of chromosome instability. Molecular modeling and biochemical experiments show that these two mutants likely disrupt a conserved oligomerization interface thereby weakening microtubule attachments. We propose a model through which weakened microtubule attachments promote increased kinetochore-microtubule turnover and thus suppress chromosome instability. In sum, our data show how a set of point mutations evolved in histone-humanized yeasts to counterbalance human histone-induced chromosomal instability through weakening microtubule interactions, eventually promoting a return to euploidy.
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Affiliation(s)
- Max A B Haase
- Institute for Systems Genetics and Department of Biochemistry and Molecular PharmacologyNYU Langone HealthNew YorkNYUSA
- Vilcek Institute of Graduate Biomedical SciencesNYU School of MedicineNew YorkNYUSA
| | - Guðjón Ólafsson
- Institute for Systems Genetics and Department of Biochemistry and Molecular PharmacologyNYU Langone HealthNew YorkNYUSA
| | - Rachel L Flores
- Department of BiochemistryUniversity of WashingtonSeattleWAUSA
| | | | - Alex Zelter
- Department of BiochemistryUniversity of WashingtonSeattleWAUSA
| | | | - Luciana Lazar‐Stefanita
- Institute for Systems Genetics and Department of Biochemistry and Molecular PharmacologyNYU Langone HealthNew YorkNYUSA
| | - David M Truong
- Department of Biomedical EngineeringNYU Tandon School of EngineeringBrooklynNYUSA
- Department of PathologyNYU Langone HealthNew YorkNYUSA
| | - Charles L Asbury
- Department of BiochemistryUniversity of WashingtonSeattleWAUSA
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | - Trisha N Davis
- Department of BiochemistryUniversity of WashingtonSeattleWAUSA
| | - Jef D Boeke
- Institute for Systems Genetics and Department of Biochemistry and Molecular PharmacologyNYU Langone HealthNew YorkNYUSA
- Department of Biomedical EngineeringNYU Tandon School of EngineeringBrooklynNYUSA
- Department of Biochemistry and Molecular PharmacologyNYU Langone HealthNew YorkNYUSA
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7
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Cairo G, Greiwe C, Jung GI, Blengini C, Schindler K, Lacefield S. Distinct Aurora B pools at the inner centromere and kinetochore have different contributions to meiotic and mitotic chromosome segregation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.05.527197. [PMID: 36778459 PMCID: PMC9915740 DOI: 10.1101/2023.02.05.527197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Proper chromosome segregation depends on establishment of bioriented kinetochore-microtubule attachments, which often requires multiple rounds of release and reattachment. Aurora B and C kinases phosphorylate kinetochore proteins to release tensionless attachments. Multiple pathways recruit Aurora B/C to the centromere and kinetochore. We studied how these pathways contribute to anaphase onset timing and correction of kinetochore-microtubule attachments in budding yeast meiosis and mitosis. We find that the pool localized by the Bub1/Bub3 pathway sets the normal duration of meiosis and mitosis, in differing ways. Our meiosis data suggests that disruption of this pathway leads to PP1 kinetochore localization, which dephosphorylates Cdc20 for premature anaphase onset. For error correction, the Bub1/Bub3 and COMA pathways are individually important in meiosis but compensatory in mitosis. Finally, we find that the haspin and Bub1/3 pathways function together to ensure error correction in mouse oogenesis. Our results suggest that each recruitment pathway localizes spatially distinct kinetochore-localized Aurora B/C pools that function differently between meiosis and mitosis.
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Affiliation(s)
- Gisela Cairo
- Indiana University, Department of Biology, Bloomington, IN USA
- Geisel School of Medicine at Dartmouth, Department of Biochemistry and Cell Biology, Hanover, NH USA
| | - Cora Greiwe
- Indiana University, Department of Biology, Bloomington, IN USA
| | - Gyu Ik Jung
- Rutgers University, Department of Genetics, Piscataway, NJ USA
| | | | - Karen Schindler
- Rutgers University, Department of Genetics, Piscataway, NJ USA
| | - Soni Lacefield
- Indiana University, Department of Biology, Bloomington, IN USA
- Geisel School of Medicine at Dartmouth, Department of Biochemistry and Cell Biology, Hanover, NH USA
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8
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Gordon MR, Zhu J, Sun G, Li R. Suppression of chromosome instability by targeting a DNA helicase in budding yeast. Mol Biol Cell 2023; 34:ar3. [PMID: 36350688 PMCID: PMC9816644 DOI: 10.1091/mbc.e22-09-0395] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Accepted: 11/04/2022] [Indexed: 11/10/2022] Open
Abstract
Chromosome instability (CIN) is an important driver of cancer initiation, progression, drug resistance, and aging. As such, genes whose inhibition suppresses CIN are potential therapeutic targets. We report here that deletion of an accessory DNA helicase, Rrm3, suppresses high CIN caused by a wide range of genetic or pharmacological perturbations in yeast. Although this helicase mutant has altered cell cycle dynamics, suppression of CIN by rrm3∆ is independent of the DNA damage and spindle assembly checkpoints. Instead, the rrm3∆ mutant may have increased kinetochore-microtubule error correction due to an altered localization of Aurora B kinase and associated phosphatase, PP2A-Rts1.
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Affiliation(s)
- Molly R. Gordon
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205
| | - Jin Zhu
- Mechanobiology Institute and
| | - Gordon Sun
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205
- Department of Biomedical Engineering and
| | - Rong Li
- Department of Cell Biology, Center for Cell Dynamics, Johns Hopkins University School of Medicine, Baltimore, MD 21205
- Mechanobiology Institute and
- Department of Biological Sciences, National University of Singapore, 117411
- Department of Chemical and Biomolecular Engineering, Whiting School of Engineering, Johns Hopkins University, Baltimore, MD 21218
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9
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Hedouin S, Logsdon GA, Underwood JG, Biggins S. A transcriptional roadblock protects yeast centromeres. Nucleic Acids Res 2022; 50:7801-7815. [PMID: 35253883 PMCID: PMC9371891 DOI: 10.1093/nar/gkac117] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/02/2022] [Accepted: 02/07/2022] [Indexed: 11/12/2022] Open
Abstract
Centromeres are the chromosomal loci essential for faithful chromosome segregation during cell division. Although centromeres are transcribed and produce non-coding RNAs (cenRNAs) that affect centromere function, we still lack a mechanistic understanding of how centromere transcription is regulated. Here, using a targeted RNA isoform sequencing approach, we identified the transcriptional landscape at and surrounding all centromeres in budding yeast. Overall, cenRNAs are derived from transcription readthrough of pericentromeric regions but rarely span the entire centromere and are a complex mixture of molecules that are heterogeneous in abundance, orientation, and sequence. While most pericentromeres are transcribed throughout the cell cycle, centromere accessibility to the transcription machinery is restricted to S-phase. This temporal restriction is dependent on Cbf1, a centromere-binding transcription factor, that we demonstrate acts locally as a transcriptional roadblock. Cbf1 deletion leads to an accumulation of cenRNAs at all phases of the cell cycle which correlates with increased chromosome mis-segregation that is partially rescued when the roadblock activity is restored. We propose that a Cbf1-mediated transcriptional roadblock protects yeast centromeres from untimely transcription to ensure genomic stability.
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Affiliation(s)
- Sabrine Hedouin
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Glennis A Logsdon
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Jason G Underwood
- Pacific Biosciences (PacBio) of California, Incorporated, Menlo Park, CA 94025, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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10
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Su XB, Wang M, Schaffner C, Nerusheva OO, Clift D, Spanos C, Kelly DA, Tatham M, Wallek A, Wu Y, Rappsilber J, Jeyaprakash AA, Storchova Z, Hay RT, Marston AL. SUMOylation stabilizes sister kinetochore biorientation to allow timely anaphase. J Cell Biol 2021; 220:e202005130. [PMID: 33929514 PMCID: PMC8094117 DOI: 10.1083/jcb.202005130] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 02/18/2021] [Accepted: 03/24/2021] [Indexed: 12/12/2022] Open
Abstract
During mitosis, sister chromatids attach to microtubules from opposite poles, called biorientation. Sister chromatid cohesion resists microtubule forces, generating tension, which provides the signal that biorientation has occurred. How tension silences the surveillance pathways that prevent cell cycle progression and correct erroneous kinetochore-microtubule attachments remains unclear. Here we show that SUMOylation dampens error correction to allow stable sister kinetochore biorientation and timely anaphase onset. The Siz1/Siz2 SUMO ligases modify the pericentromere-localized shugoshin (Sgo1) protein before its tension-dependent release from chromatin. Sgo1 SUMOylation reduces its binding to protein phosphatase 2A (PP2A), and weakening of this interaction is important for stable biorientation. Unstable biorientation in SUMO-deficient cells is associated with persistence of the chromosome passenger complex (CPC) at centromeres, and SUMOylation of CPC subunit Bir1 also contributes to timely anaphase onset. We propose that SUMOylation acts in a combinatorial manner to facilitate dismantling of the error correction machinery within pericentromeres and thereby sharpen the metaphase-anaphase transition.
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Affiliation(s)
- Xue Bessie Su
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Menglu Wang
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Claudia Schaffner
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Olga O. Nerusheva
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Dean Clift
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
- Laboratory of Molecular Biology, Medical Research Council, Cambridge, UK
| | - Christos Spanos
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - David A. Kelly
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Michael Tatham
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Andreas Wallek
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Yehui Wu
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
- Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - A. Arockia Jeyaprakash
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Zuzana Storchova
- Max Planck Institute of Biochemistry, Martinsried, Germany
- Technische Universität Kaiserslautern, Kaiserslautern, Germany
| | - Ronald T. Hay
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Adèle L. Marston
- Wellcome Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, UK
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11
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Structural and dynamic mechanisms of CBF3-guided centromeric nucleosome formation. Nat Commun 2021; 12:1763. [PMID: 33741944 PMCID: PMC7979930 DOI: 10.1038/s41467-021-21985-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 02/22/2021] [Indexed: 11/08/2022] Open
Abstract
Accurate chromosome segregation relies on the specific centromeric nucleosome-kinetochore interface. In budding yeast, the centromere CBF3 complex guides the deposition of CENP-A, an H3 variant, to form the centromeric nucleosome in a DNA sequence-dependent manner. Here, we determine the structures of the centromeric nucleosome containing the native CEN3 DNA and the CBF3core bound to the canonical nucleosome containing an engineered CEN3 DNA. The centromeric nucleosome core structure contains 115 base pair DNA including a CCG motif. The CBF3core specifically recognizes the nucleosomal CCG motif through the Gal4 domain while allosterically altering the DNA conformation. Cryo-EM, modeling, and mutational studies reveal that the CBF3core forms dynamic interactions with core histones H2B and CENP-A in the CEN3 nucleosome. Our results provide insights into the structure of the budding yeast centromeric nucleosome and the mechanism of its assembly, which have implications for analogous processes of human centromeric nucleosome formation.
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12
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Cairo G, MacKenzie AM, Lacefield S. Differential requirement for Bub1 and Bub3 in regulation of meiotic versus mitotic chromosome segregation. J Cell Biol 2020; 219:133770. [PMID: 32328625 PMCID: PMC7147105 DOI: 10.1083/jcb.201909136] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 01/02/2020] [Accepted: 01/15/2020] [Indexed: 01/21/2023] Open
Abstract
Accurate chromosome segregation depends on the proper attachment of kinetochores to spindle microtubules before anaphase onset. The Ipl1/Aurora B kinase corrects improper attachments by phosphorylating kinetochore components and so releasing aberrant kinetochore–microtubule interactions. The localization of Ipl1 to kinetochores in budding yeast depends upon multiple pathways, including the Bub1–Bub3 pathway. We show here that in meiosis, Bub3 is crucial for correction of attachment errors. Depletion of Bub3 results in reduced levels of kinetochore-localized Ipl1 and concomitant massive chromosome missegregation caused by incorrect chromosome–spindle attachments. Depletion of Bub3 also results in shorter metaphase I and metaphase II due to premature localization of protein phosphatase 1 (PP1) to kinetochores, which antagonizes Ipl1-mediated phosphorylation. We propose a new role for the Bub1–Bub3 pathway in maintaining the balance between kinetochore localization of Ipl1 and PP1, a balance that is essential for accurate meiotic chromosome segregation and timely anaphase onset.
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Affiliation(s)
- Gisela Cairo
- Department of Biology, Indiana University, Bloomington, IN
| | | | - Soni Lacefield
- Department of Biology, Indiana University, Bloomington, IN
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13
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Establishing correct kinetochore-microtubule attachments in mitosis and meiosis. Essays Biochem 2020; 64:277-287. [PMID: 32406497 DOI: 10.1042/ebc20190072] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/20/2020] [Accepted: 04/24/2020] [Indexed: 01/01/2023]
Abstract
Faithful chromosome segregation in mitosis and meiosis requires that chromosomes properly attach to spindle microtubules. Initial kinetochore-microtubule attachments are often incorrect and rely on error correction mechanisms to release improper attachments, allowing the formation of new attachments. Aurora B kinase and, in mammalian germ cells, Aurora C kinase function as the enzymatic component of the Chromosomal Passenger Complex (CPC), which localizes to the inner centromere/kinetochore and phosphorylates kinetochore proteins for microtubule release during error correction. In this review, we discuss recent findings of the molecular pathways that regulate the chromosomal localization of Aurora B and C kinases in human cell lines, mice, fission yeast, and budding yeast. We also discuss differences in the importance of localization pathways between mitosis and meiosis.
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14
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Migl D, Kschonsak M, Arthur CP, Khin Y, Harrison SC, Ciferri C, Dimitrova YN. Cryoelectron Microscopy Structure of a Yeast Centromeric Nucleosome at 2.7 Å Resolution. Structure 2020; 28:363-370.e3. [PMID: 32004465 PMCID: PMC7166091 DOI: 10.1016/j.str.2019.12.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 10/17/2019] [Accepted: 12/02/2019] [Indexed: 12/21/2022]
Abstract
Kinetochores mediate chromosome segregation during cell division. They assemble on centromeric nucleosomes and capture spindle microtubules. In budding yeast, a kinetochore links a single nucleosome, containing the histone variant Cse4CENP-A instead of H3, with a single microtubule. Conservation of most kinetochore components from yeast to metazoans suggests that the yeast kinetochore represents a module of the more complex metazoan arrangements. We describe here a streamlined protocol for reconstituting a yeast centromeric nucleosome and a systematic exploration of cryo-grid preparation. These developments allowed us to obtain a high-resolution cryoelectron microscopy reconstruction. As suggested by previous work, fewer base pairs are in tight association with the histone octamer than there are in canonical nucleosomes. Weak binding of the end DNA sequences may contribute to specific recognition by other inner kinetochore components. The centromeric nucleosome structure and the strategies we describe will facilitate studies of many other aspects of kinetochore assembly and chromatin biochemistry.
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Affiliation(s)
- David Migl
- Harvard Medical School, Boston, MA 02115, USA; Biophysics Program, Harvard University, Boston, MA 02115, USA
| | - Marc Kschonsak
- Structural Biology, Genentech, South San Francisco, CA, USA
| | | | - Yadana Khin
- Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Harrison
- Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
| | - Claudio Ciferri
- Structural Biology, Genentech, South San Francisco, CA, USA.
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15
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Lee PD, Wei H, Tan D, Harrison SC. Structure of the Centromere Binding Factor 3 Complex from Kluyveromyces lactis. J Mol Biol 2019; 431:4444-4454. [PMID: 31425683 PMCID: PMC7004469 DOI: 10.1016/j.jmb.2019.08.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 07/28/2019] [Accepted: 08/05/2019] [Indexed: 01/21/2023]
Abstract
Kinetochores are the multiprotein complexes that link chromosomal centromeres to mitotic-spindle microtubules. Budding yeast centromeres comprise three sequential "centromere-determining elements", CDEI, II, and III. CDEI (8 bp) and CDEIII (∼25 bp) are conserved between Kluyveromyces lactis and Saccharomyces cerevisiae, but CDEII in the former is twice as long (160 bp) as CDEII in the latter (80 bp). The CBF3 complex recognizes CDEIII and is required for assembly of a centromeric nucleosome, which in turn recruits other kinetochore components. To understand differences in centromeric nucleosome assembly between K. lactis and S. cerevisiae, we determined the structure of a K. lactis CBF3 complex by electron cryomicroscopy at ∼4 Å resolution and compared it with published structures of S. cerevisiae CBF3. We show differences in the pose of Ndc10 and discuss potential models of the K. lactis centromeric nucleosome that account for the extended CDEII length.
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Affiliation(s)
- Phong D. Lee
- Department of Biological Chemistry and Molecular Pharmacology Harvard Medical School Boston MA 02115 USA,Graduate Program in Virology Harvard Medical School Boston MA 02115 USA
| | - Hui Wei
- The National Resource for Automated Molecular Microscopy Simons Electron Microscopy Center New York Structural Biology Center New York NY 10027 USA
| | - Dongyan Tan
- Department of Pharmacological Sciences Stony Brook University School of Medicine Stony Brook NY 11794 USA
| | - Stephen C. Harrison
- Department of Biological Chemistry and Molecular Pharmacology Harvard Medical School Boston MA 02115 USA,Howard Hughes Medical Institute Harvard Medical School Boston MA 02115 USA
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16
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Bhattacharya A, Shukla VK, Hosur RV, Kumar A. Backbone and side-chain resonance assignments of centromeric protein Scm3 from Saccharomyces cerevisiae. BIOMOLECULAR NMR ASSIGNMENTS 2019; 13:267-273. [PMID: 30937734 DOI: 10.1007/s12104-019-09889-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 03/08/2019] [Indexed: 06/09/2023]
Abstract
The centromeric chromatin plays an essential role in regulating the attachment of microtubules and controlling the segregation of sister chromatids during mitosis. In budding yeast, the evolutionary conserved histone variant, Cse4 is a vital component of the multiprotein kinetochore complex and is recruited to the centromere through its chaperone, Suppressor of chromosome mis-segregation (Scm3). Scm3 is an inner kinetochore protein crucial for the formation of a functional inner kinetochore. Scm3 has been known to play an active role in the assembly of the centromeric nucleosome and its deletion has been found to have deleterious effects on the cells leading to chromosome segregation defects. However, structural details of monomeric full length Scm3 have remained elusive so far. Here, we report the backbone and side-chain resonance assignments of centromeric protein, Scm3. 1H, 13C and 15N chemical shifts of Scm3 have been obtained by various 2D and 3D heteronuclear NMR experiments at pH 7.4 and 283 K.
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Affiliation(s)
- Anusri Bhattacharya
- UM-DAE-Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Mumbai, 400098, India
| | - Vaibhav Kumar Shukla
- UM-DAE-Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Mumbai, 400098, India
| | - Ramakrishna V Hosur
- UM-DAE-Centre for Excellence in Basic Sciences, University of Mumbai, Kalina Campus, Mumbai, 400098, India.
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, 400076, India.
| | - Ashutosh Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, 400076, India.
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17
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Guo W, Kumar S, Görlitz F, Garcia E, Alexandrov Y, Munro I, Kelly DJ, Warren S, Thorpe P, Dunsby C, French P. Automated Fluorescence Lifetime Imaging High-Content Analysis of Förster Resonance Energy Transfer between Endogenously Labeled Kinetochore Proteins in Live Budding Yeast Cells. SLAS Technol 2019; 24:308-320. [PMID: 30629461 PMCID: PMC6537140 DOI: 10.1177/2472630318819240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/16/2018] [Accepted: 11/23/2018] [Indexed: 11/23/2022]
Abstract
We describe an open-source automated multiwell plate fluorescence lifetime imaging (FLIM) methodology to read out Förster resonance energy transfer (FRET) between fluorescent proteins (FPs) labeling endogenous kinetochore proteins (KPs) in live budding yeast cells. The low copy number of many KPs and their small spatial extent present significant challenges for the quantification of donor fluorescence lifetime in the presence of significant cellular autofluorescence and photobleaching. Automated FLIM data acquisition was controlled by µManager and incorporated wide-field time-gated imaging with optical sectioning to reduce background fluorescence. For data analysis, we used custom MATLAB-based software tools to perform kinetochore foci segmentation and local cellular background subtraction and fitted the fluorescence lifetime data using the open-source FLIMfit software. We validated the methodology using endogenous KPs labeled with mTurquoise2 FP and/or yellow FP and measured the donor fluorescence lifetimes for foci comprising 32 kinetochores with KP copy numbers as low as ~2 per kinetochore under an average labeling efficiency of 50%. We observed changes of median donor lifetime ≥250 ps for KPs known to form dimers. Thus, this FLIM high-content analysis platform enables the screening of relatively low-copy-number endogenous protein-protein interactions at spatially confined macromolecular complexes.
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Affiliation(s)
- Wenjun Guo
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Sunil Kumar
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Frederik Görlitz
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Edwin Garcia
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Yuriy Alexandrov
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Ian Munro
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Douglas J. Kelly
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- RIKEN Center for Biodynamic Systems
Research, Kobe, Japan
| | - Sean Warren
- Garvan Institute of Medical Research,
University of New South Wales, Sydney, New South Wales, Australia
| | - Peter Thorpe
- Francis Crick Institute, London,
UK
- Queen Mary University of London, London,
UK
| | - Christopher Dunsby
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
- Centre for Pathology, Imperial College
London, London, UK
| | - Paul French
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
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18
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Fischböck-Halwachs J, Singh S, Potocnjak M, Hagemann G, Solis-Mezarino V, Woike S, Ghodgaonkar-Steger M, Weissmann F, Gallego LD, Rojas J, Andreani J, Köhler A, Herzog F. The COMA complex interacts with Cse4 and positions Sli15/Ipl1 at the budding yeast inner kinetochore. eLife 2019; 8:42879. [PMID: 31112132 PMCID: PMC6546395 DOI: 10.7554/elife.42879] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 05/20/2019] [Indexed: 01/14/2023] Open
Abstract
Kinetochores are macromolecular protein complexes at centromeres that ensure accurate chromosome segregation by attaching chromosomes to spindle microtubules and integrating safeguard mechanisms. The inner kinetochore is assembled on CENP-A nucleosomes and has been implicated in establishing a kinetochore-associated pool of Aurora B kinase, a chromosomal passenger complex (CPC) subunit, which is essential for chromosome biorientation. By performing crosslink-guided in vitro reconstitution of budding yeast kinetochore complexes we showed that the Ame1/Okp1CENP-U/Q heterodimer, which forms the COMA complex with Ctf19/Mcm21CENP-P/O, selectively bound Cse4CENP-A nucleosomes through the Cse4 N-terminus. The Sli15/Ipl1INCENP/Aurora-B core-CPC interacted with COMA in vitro through the Ctf19 C-terminus whose deletion affected chromosome segregation fidelity in Sli15 wild-type cells. Tethering Sli15 to Ame1/Okp1 rescued synthetic lethality upon Ctf19 depletion in a Sli15 centromere-targeting deficient mutant. This study shows molecular characteristics of the point-centromere kinetochore architecture and suggests a role for the Ctf19 C-terminus in mediating CPC-binding and accurate chromosome segregation.
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Affiliation(s)
- Josef Fischböck-Halwachs
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Sylvia Singh
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Mia Potocnjak
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Götz Hagemann
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Victor Solis-Mezarino
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Stephan Woike
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Medini Ghodgaonkar-Steger
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Florian Weissmann
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Laura D Gallego
- Max F Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | - Julie Rojas
- Laboratory of Chromosome Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Jessica Andreani
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France
| | - Alwin Köhler
- Max F Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | - Franz Herzog
- Gene Center Munich, Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany.,Department of Biochemistry, Ludwig-Maximilians-Universität München, Munich, Germany
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19
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Hinshaw SM, Harrison SC. The structure of the Ctf19c/CCAN from budding yeast. eLife 2019; 8:44239. [PMID: 30762520 PMCID: PMC6407923 DOI: 10.7554/elife.44239] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 02/13/2019] [Indexed: 12/29/2022] Open
Abstract
Eukaryotic kinetochores connect spindlemicrotubules to chromosomal centromeres. A group of proteins called the Ctf19 complex (Ctf19c) in yeast and the constitutive centromere associated network (CCAN) in other organisms creates the foundation of a kinetochore. The Ctf19c/CCAN influences the timing of kinetochore assembly, sets its location by associating with a specialized nucleosome containing the histone H3 variant Cse4/CENP-A, and determines the organization of the microtubule attachment apparatus. We present here the structure of a reconstituted 13-subunit Ctf19c determined by cryo-electron microscopy at ~4 Å resolution. The structure accounts for known and inferred contacts with the Cse4 nucleosome and for an observed assembly hierarchy. We describe its implications for establishment of kinetochores and for their regulation by kinases throughout the cell cycle.
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Affiliation(s)
- Stephen M Hinshaw
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Howard Hughes Medical Institute, Boston, United States
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Howard Hughes Medical Institute, Boston, United States
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20
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Yan K, Zhang Z, Yang J, McLaughlin SH, Barford D. Architecture of the CBF3-centromere complex of the budding yeast kinetochore. Nat Struct Mol Biol 2018; 25:1103-1110. [PMID: 30478265 PMCID: PMC6292502 DOI: 10.1038/s41594-018-0154-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/10/2018] [Indexed: 01/01/2023]
Abstract
Kinetochores are multicomponent complexes responsible for coordinating the attachment of centromeric DNA to mitotic-spindle microtubules. The point centromeres of budding yeast are organized into three centromeric determining elements (CDEs), and are associated with the centromere-specific nucleosome Cse4. Deposition of Cse4 at CEN loci is dependent on the CBF3 complex that engages CDEIII to direct Cse4 nucleosomes to CDEII. To understand how CBF3 recognizes CDEIII and positions Cse4, we determined a cryo-EM structure of a CBF3-CEN complex. CBF3 interacts with CEN DNA as a head-to-head dimer that includes the whole of CDEIII and immediate 3' regions. Specific CEN-binding of CBF3 is mediated by a Cep3 subunit of one of the CBF3 protomers that forms major groove interactions with the conserved and essential CCG and TGT motifs of CDEIII. We propose a model for a CBF3-Cse4-CEN complex with implications for understanding CBF3-directed deposition of the Cse4 nucleosome at CEN loci.
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Affiliation(s)
- Kaige Yan
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Ziguo Zhang
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Jing Yang
- MRC Laboratory of Molecular Biology, Cambridge, UK
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21
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Zhang W, Lukoyanova N, Miah S, Lucas J, Vaughan CK. Insights into Centromere DNA Bending Revealed by the Cryo-EM Structure of the Core Centromere Binding Factor 3 with Ndc10. Cell Rep 2018; 24:744-754. [PMID: 30021170 PMCID: PMC6077249 DOI: 10.1016/j.celrep.2018.06.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 05/06/2018] [Accepted: 06/15/2018] [Indexed: 12/21/2022] Open
Abstract
The centromere binding factor 3 (CBF3) complex binds the third centromere DNA element in organisms with point centromeres, such as S. cerevisiae. It is an essential complex for assembly of the kinetochore in these organisms, as it facilitates genetic centromere specification and allows association of all other kinetochore components. We determined high-resolution structures of the core complex of CBF3 alone and in association with a monomeric construct of Ndc10, using cryoelectron microscopy (cryo-EM). We identify the DNA-binding site of the complex and present a model in which CBF3 induces a tight bend in centromeric DNA, thus facilitating assembly of the centromeric nucleosome. Cryo-EM studies of CBF3 reveal the core complex has a deep asymmetric channel The size, conservation, and charge of the channel suggest that it binds centromere DNA Unique insertions in the Ctf13 F box provide the binding site for one Ndc10 monomer The Ndc10 DNA-binding site is in plane with and perpendicular to the CBF3 channel
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Affiliation(s)
- Wenjuan Zhang
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK; Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Natalya Lukoyanova
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Shomon Miah
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK
| | - Jonathan Lucas
- Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Cara K Vaughan
- Institute of Structural and Molecular Biology, Birkbeck College, Malet Street, London WC1E 7HX, UK; Institute of Structural and Molecular Biology, University College London, Gower Street, London WC1E 6BT, UK.
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22
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Leber V, Nans A, Singleton MR. Structural basis for assembly of the CBF3 kinetochore complex. EMBO J 2018; 37:269-281. [PMID: 29212814 PMCID: PMC5771398 DOI: 10.15252/embj.201798134] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 10/30/2017] [Accepted: 11/20/2017] [Indexed: 11/09/2022] Open
Abstract
Eukaryotic chromosomes contain a specialised region known as the centromere, which forms the platform for kinetochore assembly and microtubule attachment. The centromere is distinguished by the presence of nucleosomes containing the histone H3 variant, CENP-A. In budding yeast, centromere establishment begins with the recognition of a specific DNA sequence by the CBF3 complex. This in turn facilitates CENP-ACse4 nucleosome deposition and kinetochore assembly. Here, we describe a 3.6 Å single-particle cryo-EM reconstruction of the core CBF3 complex, incorporating the sequence-specific DNA-binding protein Cep3 together with regulatory subunits Ctf13 and Skp1. This provides the first structural data on Ctf13, defining it as an F-box protein of the leucine-rich-repeat family, and demonstrates how a novel F-box-mediated interaction between Ctf13 and Skp1 is responsible for initial assembly of the CBF3 complex.
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Affiliation(s)
- Vera Leber
- Structural Biology of Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Andrea Nans
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, UK
| | - Martin R Singleton
- Structural Biology of Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
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23
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Kinetochore Function from the Bottom Up. Trends Cell Biol 2017; 28:22-33. [PMID: 28985987 DOI: 10.1016/j.tcb.2017.09.002] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 02/06/2023]
Abstract
During a single human lifetime, nearly one quintillion chromosomes separate from their sisters and transit to their destinations in daughter cells. Unlike DNA replication, chromosome segregation has no template, and, unlike transcription, errors frequently lead to a total loss of cell viability. Rapid progress in recent years has shown how kinetochores enable faithful execution of this process by connecting chromosomal DNA to microtubules. These findings have transformed our idea of kinetochores from cytological features to immense molecular machines and now allow molecular interpretation of many long-appreciated kinetochore functions. In this review we trace kinetochore protein connectivity from chromosomal DNA to microtubules, relating new findings to important points of regulation and function.
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24
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Makrantoni V, Ciesiolka A, Lawless C, Fernius J, Marston A, Lydall D, Stark MJR. A Functional Link Between Bir1 and the Saccharomyces cerevisiae Ctf19 Kinetochore Complex Revealed Through Quantitative Fitness Analysis. G3 (BETHESDA, MD.) 2017; 7:3203-3215. [PMID: 28754723 PMCID: PMC5592945 DOI: 10.1534/g3.117.300089] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2017] [Accepted: 07/25/2017] [Indexed: 11/18/2022]
Abstract
The chromosomal passenger complex (CPC) is a key regulator of eukaryotic cell division, consisting of the protein kinase Aurora B/Ipl1 in association with its activator (INCENP/Sli15) and two additional proteins (Survivin/Bir1 and Borealin/Nbl1). Here, we report a genome-wide genetic interaction screen in Saccharomyces cerevisiae using the bir1-17 mutant, identifying through quantitative fitness analysis deletion mutations that act as enhancers and suppressors. Gene knockouts affecting the Ctf19 kinetochore complex were identified as the strongest enhancers of bir1-17, while mutations affecting the large ribosomal subunit or the mRNA nonsense-mediated decay pathway caused strong phenotypic suppression. Thus, cells lacking a functional Ctf19 complex become highly dependent on Bir1 function and vice versa. The negative genetic interaction profiles of bir1-17 and the cohesin mutant mcd1-1 showed considerable overlap, underlining the strong functional connection between sister chromatid cohesion and chromosome biorientation. Loss of some Ctf19 components, such as Iml3 or Chl4, impacted differentially on bir1-17 compared with mutations affecting other CPC components: despite the synthetic lethality shown by either iml3∆ or chl4∆ in combination with bir1-17, neither gene knockout showed any genetic interaction with either ipl1-321 or sli15-3 Our data therefore imply a specific functional connection between the Ctf19 complex and Bir1 that is not shared with Ipl1.
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Affiliation(s)
- Vasso Makrantoni
- Centre for Gene Regulation and Expression, University of Dundee, DD1 5EH, UK
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - Adam Ciesiolka
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Conor Lawless
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Josefin Fernius
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - Adele Marston
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3BF, UK
| | - David Lydall
- Institute for Cell and Molecular Biosciences, Newcastle University, NE2 4HH, UK
| | - Michael J R Stark
- Centre for Gene Regulation and Expression, University of Dundee, DD1 5EH, UK
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25
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The unconventional kinetoplastid kinetochore: from discovery toward functional understanding. Biochem Soc Trans 2017; 44:1201-1217. [PMID: 27911702 PMCID: PMC5095916 DOI: 10.1042/bst20160112] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 06/15/2016] [Accepted: 06/21/2016] [Indexed: 11/17/2022]
Abstract
The kinetochore is the macromolecular protein complex that drives chromosome segregation in eukaryotes. Its most fundamental function is to connect centromeric DNA to dynamic spindle microtubules. Studies in popular model eukaryotes have shown that centromere protein (CENP)-A is critical for DNA-binding, whereas the Ndc80 complex is essential for microtubule-binding. Given their conservation in diverse eukaryotes, it was widely believed that all eukaryotes would utilize these components to make up a core of the kinetochore. However, a recent study identified an unconventional type of kinetochore in evolutionarily distant kinetoplastid species, showing that chromosome segregation can be achieved using a distinct set of proteins. Here, I review the discovery of the two kinetochore systems and discuss how their studies contribute to a better understanding of the eukaryotic chromosome segregation machinery.
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26
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Fink S, Turnbull K, Desai A, Campbell CS. An engineered minimal chromosomal passenger complex reveals a role for INCENP/Sli15 spindle association in chromosome biorientation. J Cell Biol 2017; 216:911-923. [PMID: 28314741 PMCID: PMC5379952 DOI: 10.1083/jcb.201609123] [Citation(s) in RCA: 21] [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: 09/28/2016] [Revised: 01/13/2017] [Accepted: 02/01/2017] [Indexed: 11/22/2022] Open
Abstract
The four-subunit chromosomal passenger complex (CPC), whose enzymatic subunit is Aurora B kinase, promotes chromosome biorientation by detaching incorrect kinetochore-microtubule attachments. In this study, we use a combination of truncations and artificial dimerization in budding yeast to define the minimal CPC elements essential for its biorientation function. We engineered a minimal CPC comprised of the dimerized last third of the kinase-activating Sli15/INCENP scaffold and the catalytic subunit Ipl1/Aurora B. Although native Sli15 is not oligomeric, artificial dimerization suppressed the biorientation defect and lethality associated with deletion of a majority of its microtubule-binding domain. Dimerization did not act through a physical clustering-based kinase activation mechanism but instead promoted spindle association, likely via a putative helical domain in Sli15 that is essential even when dimerized and is required to target kinetochore substrates. Based on the engineering and characterization of a minimal CPC, we suggest that spindle association is important for active Ipl1/Aurora B complexes to preferentially destabilize misattached kinetochores.
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Affiliation(s)
- Sarah Fink
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
| | - Kira Turnbull
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Arshad Desai
- Ludwig Institute for Cancer Research, University of California, San Diego, La Jolla, CA 92093
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Christopher S Campbell
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, 1030 Vienna, Austria
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Musacchio A, Desai A. A Molecular View of Kinetochore Assembly and Function. BIOLOGY 2017; 6:E5. [PMID: 28125021 PMCID: PMC5371998 DOI: 10.3390/biology6010005] [Citation(s) in RCA: 310] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 12/15/2022]
Abstract
Kinetochores are large protein assemblies that connect chromosomes to microtubules of the mitotic and meiotic spindles in order to distribute the replicated genome from a mother cell to its daughters. Kinetochores also control feedback mechanisms responsible for the correction of incorrect microtubule attachments, and for the coordination of chromosome attachment with cell cycle progression. Finally, kinetochores contribute to their own preservation, across generations, at the specific chromosomal loci devoted to host them, the centromeres. They achieve this in most species by exploiting an epigenetic, DNA-sequence-independent mechanism; notable exceptions are budding yeasts where a specific sequence is associated with centromere function. In the last 15 years, extensive progress in the elucidation of the composition of the kinetochore and the identification of various physical and functional modules within its substructure has led to a much deeper molecular understanding of kinetochore organization and the origins of its functional output. Here, we provide a broad summary of this progress, focusing primarily on kinetochores of humans and budding yeast, while highlighting work from other models, and present important unresolved questions for future studies.
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Affiliation(s)
- Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn Straße 11, Dortmund 44227, Germany.
- Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Essen 45117, Germany.
| | - Arshad Desai
- Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA.
- Department of Cellular & Molecular Medicine, 9500 Gilman Dr., La Jolla, CA 92093, USA.
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Bloom K, Costanzo V. Centromere Structure and Function. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2017; 56:515-539. [PMID: 28840251 DOI: 10.1007/978-3-319-58592-5_21] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The centromere is the genetic locus that specifies the site of kinetochore assembly, where the chromosome will attach to the kinetochore microtubule. The pericentromere is the physical region responsible for the geometry of bi-oriented sister kinetochores in metaphase. In budding yeast the 125 bp point centromere is sufficient to specify kinetochore assembly. The flanking region is enriched (3X) in cohesin and condensin relative to the remaining chromosome arms. The enrichment spans about 30-50 kb around each centromere. We refer to the flanking chromatin as the pericentromere in yeast. In mammals, a 5-10 Mb region dictates where the kinetochore is built. The kinetochore interacts with a very small fraction of DNA on the surface of the centromeric region. The remainder of the centromere lies between the sister kinetochores. This is typically called centromere chromatin. The chromatin sites that directly interface to microtubules cannot be identified due to the repeated sequence within the mammalian centromere. However in both yeast and mammals, the total amount of DNA between the sites of microtubule attachment in metaphase is highly conserved. In yeast the 16 chromosomes are clustered into a 250 nm diameter region, and 800 kb (16 × 50 kb) or ~1 Mb of DNA lies between sister kinetochores. In mammals, 5-10 Mb lies between sister kinetochores. In both organisms the sister kinetochores are separated by about 1 μm. Thus, centromeres of different organisms differ in how they specify kinetochore assembly, but there may be important centromere chromatin functions that are conserved throughout phylogeny. Recently, centromeric chromatin has been reconstituted in vitro using alpha satellite DNA revealing unexpected features of centromeric DNA organization, replication, and response to stress. We will focus on the conserved features of centromere in this review.
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Affiliation(s)
- Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, 623 Fordham Hall CB#3280, Chapel Hill, NC, 27599-3280, USA.
| | - Vincenzo Costanzo
- DNA Metabolism Laboratory, IFOM, The FIRC Institute of Molecular Oncology, Vai Adamello 16, 21139, Milan, Italy
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29
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Whole Genome Analysis of 132 Clinical Saccharomyces cerevisiae Strains Reveals Extensive Ploidy Variation. G3-GENES GENOMES GENETICS 2016; 6:2421-34. [PMID: 27317778 PMCID: PMC4978896 DOI: 10.1534/g3.116.029397] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Budding yeast has undergone several independent transitions from commercial to clinical lifestyles. The frequency of such transitions suggests that clinical yeast strains are derived from environmentally available yeast populations, including commercial sources. However, despite their important role in adaptive evolution, the prevalence of polyploidy and aneuploidy has not been extensively analyzed in clinical strains. In this study, we have looked for patterns governing the transition to clinical invasion in the largest screen of clinical yeast isolates to date. In particular, we have focused on the hypothesis that ploidy changes have influenced adaptive processes. We sequenced 144 yeast strains, 132 of which are clinical isolates. We found pervasive large-scale genomic variation in both overall ploidy (34% of strains identified as 3n/4n) and individual chromosomal copy numbers (36% of strains identified as aneuploid). We also found evidence for the highly dynamic nature of yeast genomes, with 35 strains showing partial chromosomal copy number changes and eight strains showing multiple independent chromosomal events. Intriguingly, a lineage identified to be baker's/commercial derived with a unique damaging mutation in NDC80 was particularly prone to polyploidy, with 83% of its members being triploid or tetraploid. Polyploidy was in turn associated with a >2× increase in aneuploidy rates as compared to other lineages. This dataset provides a rich source of information on the genomics of clinical yeast strains and highlights the potential importance of large-scale genomic copy variation in yeast adaptation.
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Thu YM, Van Riper SK, Higgins L, Zhang T, Becker JR, Markowski TW, Nguyen HD, Griffin TJ, Bielinsky AK. Slx5/Slx8 Promotes Replication Stress Tolerance by Facilitating Mitotic Progression. Cell Rep 2016; 15:1254-65. [PMID: 27134171 DOI: 10.1016/j.celrep.2016.04.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 01/30/2016] [Accepted: 03/31/2016] [Indexed: 11/30/2022] Open
Abstract
Loss of minichromosome maintenance protein 10 (Mcm10) causes replication stress. We uncovered that S. cerevisiae mcm10-1 mutants rely on the E3 SUMO ligase Mms21 and the SUMO-targeted ubiquitin ligase complex Slx5/8 for survival. Using quantitative mass spectrometry, we identified changes in the SUMO proteome of mcm10-1 mutants and revealed candidates regulated by Slx5/8. Such candidates included subunits of the chromosome passenger complex (CPC), Bir1 and Sli15, known to facilitate spindle assembly checkpoint (SAC) activation. We show here that Slx5 counteracts SAC activation in mcm10-1 mutants under conditions of moderate replication stress. This coincides with the proteasomal degradation of sumoylated Bir1. Importantly, Slx5-dependent mitotic relief was triggered not only by Mcm10 deficiency but also by treatment with low doses of the alkylating drug methyl methanesulfonate. Based on these findings, we propose a model in which Slx5/8 allows for passage through mitosis when replication stress is tolerable.
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Affiliation(s)
- Yee Mon Thu
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Susan Kaye Van Riper
- University of Minnesota Informatics Institute, University of Minnesota, Minneapolis, MN 55455, USA
| | - LeeAnn Higgins
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tianji Zhang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jordan Robert Becker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Todd William Markowski
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Hai Dang Nguyen
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Timothy Jon Griffin
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Anja Katrin Bielinsky
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
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Díaz-Ingelmo O, Martínez-García B, Segura J, Valdés A, Roca J. DNA Topology and Global Architecture of Point Centromeres. Cell Rep 2015; 13:667-677. [PMID: 26489472 DOI: 10.1016/j.celrep.2015.09.039] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 08/08/2015] [Accepted: 09/14/2015] [Indexed: 12/21/2022] Open
Abstract
DNA is wrapped in a left-handed fashion around histone octasomes containing the centromeric histone H3 variant CENP-A. However, DNA topology studies have suggested that DNA is wrapped in a right-handed manner around the CENP-A nucleosome that occupies the yeast point centromere. Here, we determine the DNA linking number difference (ΔLk) stabilized by the yeast centromere and the contribution of the centromere determining elements (CDEI, CDEII, and CDEIII). We show that the intrinsic architecture of the yeast centromere stabilizes +0.6 units of ΔLk. This topology depends on the integrity of CDEII and CDEIII, but it is independent of cbf1 binding to CDEI and of the variable length of CDEII. These findings suggest that the interaction of the CBF3 complex with CDEIII and a distal CDEII segment configures a right-handed DNA loop that excludes CDEI. This loop is then occupied by a CENP-A histone complex, which does not have to be inherently right-handed.
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Affiliation(s)
- Ofelia Díaz-Ingelmo
- Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain
| | - Belén Martínez-García
- Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain
| | - Joana Segura
- Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain
| | - Antonio Valdés
- Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain
| | - Joaquim Roca
- Molecular Biology Institute of Barcelona (IBMB), Spanish National Research Council (CSIC), Barcelona 08028, Spain.
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32
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Krenn V, Musacchio A. The Aurora B Kinase in Chromosome Bi-Orientation and Spindle Checkpoint Signaling. Front Oncol 2015; 5:225. [PMID: 26528436 PMCID: PMC4607871 DOI: 10.3389/fonc.2015.00225] [Citation(s) in RCA: 189] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/30/2015] [Indexed: 11/13/2022] Open
Abstract
Aurora B, a member of the Aurora family of serine/threonine protein kinases, is a key player in chromosome segregation. As part of a macromolecular complex known as the chromosome passenger complex, Aurora B concentrates early during mitosis in the proximity of centromeres and kinetochores, the sites of attachment of chromosomes to spindle microtubules. There, it contributes to a number of processes that impart fidelity to cell division, including kinetochore stabilization, kinetochore–microtubule attachment, and the regulation of a surveillance mechanism named the spindle assembly checkpoint. In the regulation of these processes, Aurora B is the fulcrum of a remarkably complex network of interactions that feed back on its localization and activation state. In this review, we discuss the multiple roles of Aurora B during mitosis, focusing in particular on its role at centromeres and kinetochores. Many details of the network of interactions at these locations remain poorly understood, and we focus here on several crucial outstanding questions.
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Affiliation(s)
- Veronica Krenn
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology , Dortmund , Germany ; Faculty of Biology, Centre for Medical Biotechnology, University Duisburg-Essen , Essen , Germany
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33
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Peplowska K, Wallek AU, Storchova Z. Sgo1 regulates both condensin and Ipl1/Aurora B to promote chromosome biorientation. PLoS Genet 2014; 10:e1004411. [PMID: 24945276 PMCID: PMC4063673 DOI: 10.1371/journal.pgen.1004411] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 04/16/2014] [Indexed: 12/23/2022] Open
Abstract
Correct chromosome segregation is essential in order to prevent aneuploidy. To segregate sister chromatids equally to daughter cells, the sisters must attach to microtubules emanating from opposite spindle poles. This so-called biorientation manifests itself by increased tension and conformational changes across kinetochores and pericentric chromatin. Tensionless attachments are dissolved by the activity of the conserved mitotic kinase Aurora B/Ipl1, thereby promoting the formation of correctly attached chromosomes. Recruitment of the conserved centromeric protein shugoshin is essential for biorientation, but its exact role has been enigmatic. Here, we identify a novel function of shugoshin (Sgo1 in budding yeast) that together with the protein phosphatase PP2A-Rts1 ensures localization of condensin to the centromeric chromatin in yeast Saccharomyces cerevisiae. Failure to recruit condensin results in an abnormal conformation of the pericentric region and impairs the correction of tensionless chromosome attachments. Moreover, we found that shugoshin is required for maintaining Aurora B/Ipl1 localization on kinetochores during metaphase. Thus, shugoshin has a dual function in promoting biorientation in budding yeast: first, by its ability to facilitate condensin recruitment it modulates the conformation of the pericentric chromatin. Second, shugoshin contributes to the maintenance of Aurora B/Ipl1 at the kinetochore during gradual establishment of bipolarity in budding yeast mitosis. Our findings identify shugoshin as a versatile molecular adaptor that governs chromosome biorientation. Accurate chromosome segregation is required for the equal distribution of genetic information to progeny. Failure to equally segregate chromosomes leads to aneuploidy, cell death or cancer. Proteins of the conserved shugoshin family contribute to accurate chromosome segregation in both meiosis and mitosis. The role of shugoshin in protection of centromeric cohesion during meiosis is well understood, but only little is known about shugoshin's function during mitosis. We show that Sgo1 mediates localization of the heterotrimeric phosphatase PP2A-Rts1 to the centromere and that this is in turn important for the efficient recruitment of condensin to the centromere. The failure to load centromeric condensin results in a defect during correction of improper microtubule-kinetochore attachments. Moreover, Sgo1 facilitates the maintenance of a centromeric pool of Aurora B/Ipl1, a conserved mitotic kinase essential for the correction of faulty microtubule-kinetochore attachments. Our results show that Sgo1 operates as a multifunctional hub that coordinates two centromeric functions essential for correct chromosome segregation.
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Affiliation(s)
- Karolina Peplowska
- Group Maintenance of Genome Stability, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Andreas U. Wallek
- Group Maintenance of Genome Stability, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Zuzana Storchova
- Group Maintenance of Genome Stability, Max Planck Institute of Biochemistry, Martinsried, Germany
- * E-mail:
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34
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Yamagishi Y, Sakuno T, Goto Y, Watanabe Y. Kinetochore composition and its function: lessons from yeasts. FEMS Microbiol Rev 2014; 38:185-200. [PMID: 24666101 DOI: 10.1111/1574-6976.12049] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 10/15/2013] [Accepted: 10/18/2013] [Indexed: 12/16/2022] Open
Abstract
Proper chromosome segregation during cell division is essential for proliferation, and this is facilitated by kinetochores, large protein complexes assembled on the centromeric region of the chromosomes. Although the sequences of centromeric DNA differ totally among organisms, many components of the kinetochores assembled on centromeres are very well conserved among eukaryotes. To define the identity of centromeres, centromere protein A (CENP-A), which is homologous to canonical histone H3, acts as a landmark for kinetochore assembly. Kinetochores mediate spindle–microtubule attachment and control the movement of chromosomes during mitosis and meiosis. To conduct faithful chromosome segregation, kinetochore assembly and microtubule attachment are elaborately regulated. Here we review the current understanding of the composition, assembly, functions and regulation of kinetochores revealed mainly through studies on fission and budding yeasts. Moreover, because recent cumulative evidence suggests the importance of the regulation of the orientation of kinetochore–microtubule attachment, which differs distinctly between mitosis and meiosis, we focus especially on the molecular mechanisms underlying this regulation.
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35
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Wisniewski J, Hajj B, Chen J, Mizuguchi G, Xiao H, Wei D, Dahan M, Wu C. Imaging the fate of histone Cse4 reveals de novo replacement in S phase and subsequent stable residence at centromeres. eLife 2014; 3:e02203. [PMID: 24844245 PMCID: PMC4067749 DOI: 10.7554/elife.02203] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The budding yeast centromere contains Cse4, a specialized histone H3 variant. Fluorescence pulse-chase analysis of an internally tagged Cse4 reveals that it is replaced with newly synthesized molecules in S phase, remaining stably associated with centromeres thereafter. In contrast, C-terminally-tagged Cse4 is functionally impaired, showing slow cell growth, cell lethality at elevated temperatures, and extra-centromeric nuclear accumulation. Recent studies using such strains gave conflicting findings regarding the centromeric abundance and cell cycle dynamics of Cse4. Our findings indicate that internally tagged Cse4 is a better reporter of the biology of this histone variant. Furthermore, the size of centromeric Cse4 clusters was precisely mapped with a new 3D-PALM method, revealing substantial compaction during anaphase. Cse4-specific chaperone Scm3 displays steady-state, stoichiometric co-localization with Cse4 at centromeres throughout the cell cycle, while undergoing exchange with a nuclear pool. These findings suggest that a stable Cse4 nucleosome is maintained by dynamic chaperone-in-residence Scm3.DOI: http://dx.doi.org/10.7554/eLife.02203.001.
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Affiliation(s)
- Jan Wisniewski
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, United States
| | - Bassam Hajj
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Jiji Chen
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Gaku Mizuguchi
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, United States
| | - Hua Xiao
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, United States
| | - Debbie Wei
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, United States
| | - Maxime Dahan
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Carl Wu
- Janelia Farm Research Campus, Howard Hughes Medical Institute, Ashburn, United States Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, United States
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36
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Abstract
The propagation of all organisms depends on the accurate and orderly segregation of chromosomes in mitosis and meiosis. Budding yeast has long served as an outstanding model organism to identify the components and underlying mechanisms that regulate chromosome segregation. This review focuses on the kinetochore, the macromolecular protein complex that assembles on centromeric chromatin and maintains persistent load-bearing attachments to the dynamic tips of spindle microtubules. The kinetochore also serves as a regulatory hub for the spindle checkpoint, ensuring that cell cycle progression is coupled to the achievement of proper microtubule-kinetochore attachments. Progress in understanding the composition and overall architecture of the kinetochore, as well as its properties in making and regulating microtubule attachments and the spindle checkpoint, is discussed.
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37
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Phosphorylation of Sli15 by Ipl1 is important for proper CPC localization and chromosome stability in Saccharomyces cerevisiae. PLoS One 2014; 9:e89399. [PMID: 24558497 PMCID: PMC3928436 DOI: 10.1371/journal.pone.0089399] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/19/2014] [Indexed: 12/29/2022] Open
Abstract
The chromosomal passenger complex (CPC) is a key regulator of eukaryotic cell division, consisting of the protein kinase Aurora B/Ipl1 in association with its activator (INCENP/Sli15) and two additional proteins (Survivin/Bir1 and Borealin/Nbl1). Here we have identified multiple sites of CPC autophosphorylation on yeast Sli15 that are located within its central microtubule-binding domain and examined the functional significance of their phosphorylation by Ipl1 through mutation of these sites, either to non-phosphorylatable alanine (sli15-20A) or to acidic residues to mimic constitutive phosphorylation (sli15-20D). Both mutant sli15 alleles confer chromosome instability, but this is mediated neither by changes in the capacity of Sli15 to activate Ipl1 kinase nor by decreased efficiency of chromosome biorientation, a key process in cell division that requires CPC function. Instead, we find that mimicking constitutive phosphorylation of Sli15 on the Ipl1 phosphorylation sites causes delocalization of the CPC in metaphase, whereas blocking phosphorylation of Sli15 on the Ipl1 sites drives excessive localization of Sli15 to the mitotic spindle in pre-anaphase cells. Consistent with these results, direct interaction of Sli15 with microtubules in vitro is greatly reduced either following phosphorylation by Ipl1 or when constitutive phosphorylation at the Ipl1-dependent phosphorylation sites is mimicked by aspartate or glutamate substitutions. Furthermore, we find that mimicking Ipl1 phosphorylation of Sli15 interferes with the ‘tension checkpoint’ – the CPC-dependent mechanism through which cells activate the spindle assembly checkpoint to delay anaphase in the absence of tension on kinetochore-microtubule attachments. Ipl1-dependent phosphorylation of Sli15 therefore inhibits its association with microtubules both in vivo and in vitro and may negatively regulate the tension checkpoint mechanism.
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Verzijlbergen KF, Nerusheva OO, Kelly D, Kerr A, Clift D, de Lima Alves F, Rappsilber J, Marston AL. Shugoshin biases chromosomes for biorientation through condensin recruitment to the pericentromere. eLife 2014; 3:e01374. [PMID: 24497542 PMCID: PMC3910079 DOI: 10.7554/elife.01374] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
To protect against aneuploidy, chromosomes must attach to microtubules from opposite poles (‘biorientation’) prior to their segregation during mitosis. Biorientation relies on the correction of erroneous attachments by the aurora B kinase, which destabilizes kinetochore-microtubule attachments that lack tension. Incorrect attachments are also avoided because sister kinetochores are intrinsically biased towards capture by microtubules from opposite poles. Here, we show that shugoshin acts as a pericentromeric adaptor that plays dual roles in biorientation in budding yeast. Shugoshin maintains the aurora B kinase at kinetochores that lack tension, thereby engaging the error correction machinery. Shugoshin also recruits the chromosome-organizing complex, condensin, to the pericentromere. Pericentromeric condensin biases sister kinetochores towards capture by microtubules from opposite poles. Our findings uncover the molecular basis of the bias to sister kinetochore capture and expose shugoshin as a pericentromeric hub controlling chromosome biorientation. DOI:http://dx.doi.org/10.7554/eLife.01374.001 When a cell divides to create two new daughter cells, it must produce a copy of each of its chromosomes. It is important that each daughter cell gets just one copy of each chromosome. If an error occurs and one cell gets two copies of a single chromosome, it can lead to cancer or birth defects. Fortunately, there are multiple checks to ensure that this does not happen. During cell division the chromosomes line up in a way that increases the likelihood that each daughter cell will have one copy of each chromosome. After this process—which is called biorientation—is completed, microtubules pull the chromosomes to opposite ends of the cell, which then divides. Proteins called shugoshin proteins are known to be involved in biorientation in many organisms. These proteins are found in a region called the pericentromere, which surrounds the area on the chromosomes that the microtubules attach to, but the details of their involvement in biorientation are not fully understood. Now Verzijlbergen et al. have exploited sophisticated genetic techniques in yeast to explore how shugoshin proteins work. These experiments showed that the shugoshin protein helps to recruit condensin—a protein that keeps the DNA organized within the chromosome—to the pericentromere to assist with biorientation. It also keeps aurora B kinase—one of the enzymes that helps to correct errors during cell division—in the pericentromere when a microtubule attaches to the wrong chromosome. These results help us understand how a ‘hub’ in the pericentromere ensures biorientation. The next challenge will be to understand how this hub is disassembled after biorientation to allow error-free cell division to proceed. As shugoshins have been found to be damaged in some cancers, understanding the workings of this hub could also shed new light on how they contribute to disease. DOI:http://dx.doi.org/10.7554/eLife.01374.002
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Affiliation(s)
- Kitty F Verzijlbergen
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
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39
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Marston AL. Chromosome segregation in budding yeast: sister chromatid cohesion and related mechanisms. Genetics 2014; 196:31-63. [PMID: 24395824 PMCID: PMC3872193 DOI: 10.1534/genetics.112.145144] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 09/18/2013] [Indexed: 12/28/2022] Open
Abstract
Studies on budding yeast have exposed the highly conserved mechanisms by which duplicated chromosomes are evenly distributed to daughter cells at the metaphase-anaphase transition. The establishment of proteinaceous bridges between sister chromatids, a function provided by a ring-shaped complex known as cohesin, is central to accurate segregation. It is the destruction of this cohesin that triggers the segregation of chromosomes following their proper attachment to microtubules. Since it is irreversible, this process must be tightly controlled and driven to completion. Furthermore, during meiosis, modifications must be put in place to allow the segregation of maternal and paternal chromosomes in the first division for gamete formation. Here, I review the pioneering work from budding yeast that has led to a molecular understanding of the establishment and destruction of cohesion.
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Affiliation(s)
- Adele L Marston
- The Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JR, United Kingdom
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40
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Kinetochore function and chromosome segregation rely on critical residues in histones H3 and H4 in budding yeast. Genetics 2013; 195:795-807. [PMID: 24037263 DOI: 10.1534/genetics.113.152082] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Accurate chromosome segregation requires that sister kinetochores biorient and attach to microtubules from opposite poles. Kinetochore biorientation relies on the underlying centromeric chromatin, which provides a platform to assemble the kinetochore and to recruit the regulatory factors that ensure the high fidelity of this process. To identify the centromeric chromatin determinants that contribute to chromosome segregation, we performed two complementary unbiased genetic screens using a library of budding yeast mutants in every residue of histone H3 and H4. In one screen, we identified mutants that lead to increased loss of a nonessential chromosome. In the second screen, we isolated mutants whose viability depends on a key regulator of biorientation, the Aurora B protein kinase. Nine mutants were common to both screens and exhibited kinetochore biorientation defects. Four of the mutants map near the unstructured nucleosome entry site, and their genetic interaction with reduced IPL1 can be suppressed by increasing the dosage of SGO1, a key regulator of biorientation. In addition, the composition of purified kinetochores was altered in six of the mutants. Together, this work identifies previously unknown histone residues involved in chromosome segregation and lays the foundation for future studies on the role of the underlying chromatin structure in chromosome segregation.
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Westermann S, Schleiffer A. Family matters: structural and functional conservation of centromere-associated proteins from yeast to humans. Trends Cell Biol 2013; 23:260-9. [DOI: 10.1016/j.tcb.2013.01.010] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/22/2013] [Accepted: 01/31/2013] [Indexed: 01/19/2023]
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Furuyama T, Codomo CA, Henikoff S. Reconstitution of hemisomes on budding yeast centromeric DNA. Nucleic Acids Res 2013; 41:5769-83. [PMID: 23620291 PMCID: PMC3675498 DOI: 10.1093/nar/gkt314] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The structure of nucleosomes that contain the cenH3 histone variant has been controversial. In budding yeast, a single right-handed cenH3/H4/H2A/H2B tetramer wraps the ∼80-bp Centromere DNA Element II (CDE II) sequence of each centromere into a ‘hemisome’. However, attempts to reconstitute cenH3 particles in vitro have yielded exclusively ‘octasomes’, which are observed in vivo on chromosome arms only when Cse4 (yeast cenH3) is overproduced. Here, we show that Cse4 octamers remain intact under conditions of low salt and urea that dissociate H3 octamers. However, particles consisting of two DNA duplexes wrapped around a Cse4 octamer and separated by a gap efficiently split into hemisomes. Hemisome dimensions were confirmed using a calibrated gel-shift assay and atomic force microscopy, and their identity as tightly wrapped particles was demonstrated by gelFRET. Surprisingly, Cse4 hemisomes were stable in 4 M urea. Stable Cse4 hemisomes could be reconstituted using either full-length or tailless histones and with a 78-bp CDEII segment, which is predicted to be exceptionally stiff. We propose that CDEII DNA stiffness evolved to favor Cse4 hemisome over octasome formation. The precise correspondence between Cse4 hemisomes resident on CDEII in vivo and reconstituted on CDEII in vitro without any other factors implies that CDEII is sufficient for hemisome assembly.
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Affiliation(s)
- Takehito Furuyama
- Howard Hughes Medical Institute and Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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Tension sensing by Aurora B kinase is independent of survivin-based centromere localization. Nature 2013; 497:118-21. [PMID: 23604256 PMCID: PMC3644022 DOI: 10.1038/nature12057] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 03/05/2013] [Indexed: 12/18/2022]
Abstract
Accurate segregation of the replicated genome requires chromosome biorientation on the spindle. Biorientation is ensured by Aurora B kinase, a member of the 4-subunit chromosomal passenger complex (CPC)1,2. Localization of the CPC to the inner centromere is central to the current model for how tension ensures chromosome biorientation—kinetochore-spindle attachments not under tension remain close to the inner centromere and are destabilized by Aurora B phosphorylation, whereas kinetochores under tension are pulled away from the influence of Aurora B, stabilizing their microtubule attachments3–5. Here we show that an engineered truncation of the INCENP/Sli15 subunit of budding yeast CPC that eliminates association with the inner centromere nevertheless supports proper chromosome segregation during both mitosis and meiosis. Truncated INCENP/Sli15 suppresses the deletion phenotypes of the inner centromere-targeting proteins Survivin/Bir1, Borealin/Nbl1, Bub1 and Sgo16. Unlike wildtype INCENP/Sli15, truncated INCENP/Sli15 localizes to pre-anaphase spindle microtubules. Premature targeting of full-length INCENP/Sli15 to microtubules by preventing Cdk1 phosphorylation also suppresses inviability of Survivin/Bir1 deletion. These results suggest that activation of Aurora B/Ipl1 by clustering either on chromatin or on microtubules is sufficient for chromosome biorientation.
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Quénet D, Dalal Y. The CENP-A nucleosome: a dynamic structure and role at the centromere. Chromosome Res 2012; 20:465-79. [PMID: 22825424 DOI: 10.1007/s10577-012-9301-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The centromere is a specialized locus that directs the formation of the kinetochore protein complex for correct chromosome segregation. The specific centromere histone H3 variant CENP-A has been described as the epigenetic mark of this chromatin region. Several laboratories have explored its properties, its partners, and its role in centromere formation. Specifically, two types of CENP-A nucleosomes have been described, suggesting there may be more complexity involved in centromere structure than previously thought. Recent work adds to this paradox by questioning the role of CENP-A as a unique centromeric mark and highlighting the assembly of a functional kinetochore in the absence of CENP-A. In this review, we discuss recent literature on the CENP-A nucleosomes and the debate on its role in kinetochore formation and centromere identity.
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Affiliation(s)
- Delphine Quénet
- Laboratory of Receptor Biology & Gene Expression-NCI-NIH, Building 41, Room B901, 41 Library Drive MSC 5055, Bethesda, MD 20892, USA
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Kao YF, Lou YC, Yeh YH, Hsiao CD, Chen C. Solution structure of the C-terminal NP-repeat domain of Tic40, a co-chaperone during protein import into chloroplasts. J Biochem 2012; 152:443-51. [PMID: 22888115 DOI: 10.1093/jb/mvs086] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Chloroplasts protein precursors translated in the cytosol traverse the membranes to reach their intended destination with the help of translocon complexes called translocon at the outer envelope of chloroplasts and translocon at the inner envelope of chloroplasts (TIC), respectively. Two components of the TIC translocon, Tic110 and Tic40, which combine with Hsp93 (ClpC), are involved in protein translocation across the inner membrane into the stroma. The C-terminal NP-repeat domain of Tic40 (Tic40-NP) is homologous to the DP-repeat domain of co-chaperones Hsp70-interacting and Hsp70/Hsp90-organizing proteins. Interaction of Tic40-NP and Hsp93 stimulates ATP hydrolysis of Hsp93, but the hydrolysis is abolished in both N320A and N329A mutants of Tic40-NP. Here, we determined the nuclear magnetic resonance structure of Tic40-NP, which mainly consists of five α-helices stabilized by two hydrophobic cores. In addition, chemical shift perturbation results suggested that some residues at α1 and α5, as well as residues Asn320 and Asn329, cause conformational change on the two mutants, which may subsequently affect their binding to Hsp93. We provide valuable information for further investigating how Tic40-NP interacts with Hsp93.
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Affiliation(s)
- Yi-Fen Kao
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
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Perriches T, Singleton MR. Structure of yeast kinetochore Ndc10 DNA-binding domain reveals unexpected evolutionary relationship to tyrosine recombinases. J Biol Chem 2012; 287:5173-9. [PMID: 22215672 PMCID: PMC3281669 DOI: 10.1074/jbc.c111.318501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 12/21/2011] [Indexed: 11/06/2022] Open
Abstract
We have solved the x-ray structure of the N-terminal half of the yeast kinetochore protein Ndc10 at 1.9 Å resolution. This essential protein is a key constituent of the budding yeast centromere and is essential for the recruitment of the centromeric nucleosome and establishment of the kinetochore. The fold of the protein shows unexpected similarities to the tyrosine recombinase/λ-integrase family of proteins, most notably Cre, with some variation in the relative position of the subdomains. This finding offers new insights into kinetochore evolution and the adaptation of a well studied protein fold to a novel role. By comparison with tyrosine recombinases and mutagenesis studies, we have been able to define some of the key DNA-binding motifs.
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Affiliation(s)
- Thibaud Perriches
- From the Macromolecular Structure and Function Laboratory, Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, United Kingdom
| | - Martin R. Singleton
- From the Macromolecular Structure and Function Laboratory, Cancer Research UK London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, United Kingdom
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