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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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Hinshaw SM, Quan Y, Cai J, Zhou AL, Zhou H. Multi-site phosphorylation of yeast Mif2/CENP-C promotes inner kinetochore assembly. Curr Biol 2023; 33:688-696.e6. [PMID: 36736323 PMCID: PMC9992315 DOI: 10.1016/j.cub.2023.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/28/2022] [Accepted: 01/09/2023] [Indexed: 02/05/2023]
Abstract
Kinetochores control eukaryotic chromosome segregation by connecting chromosomal centromeres to spindle microtubules. Duplication of centromeric DNA necessitates kinetochore disassembly and subsequent reassembly on nascent sisters. To search for a regulatory mechanism that controls the earliest steps of this process, we studied Mif2/CENP-C, an essential basal component of the kinetochore. We found that phosphorylation of a central region of Mif2 (Mif2-PEST) enhances inner kinetochore assembly. Eliminating Mif2-PEST phosphorylation sites progressively impairs cellular fitness. The most severe Mif2-PEST mutations are lethal in cells lacking otherwise non-essential inner kinetochore factors. These data show that multi-site phosphorylation of Mif2/CENP-C controls inner kinetochore assembly.
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Affiliation(s)
- Stephen M Hinshaw
- Stanford Cancer Institute, Stanford School of Medicine, 1291 Welch Road, Stanford, CA 94305, USA.
| | - Yun Quan
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Jiaxi Cai
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Ann L Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Huilin Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA.
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Sridhar S, Fukagawa T. Kinetochore Architecture Employs Diverse Linker Strategies Across Evolution. Front Cell Dev Biol 2022; 10:862637. [PMID: 35800888 PMCID: PMC9252888 DOI: 10.3389/fcell.2022.862637] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 05/23/2022] [Indexed: 01/09/2023] Open
Abstract
The assembly of a functional kinetochore on centromeric chromatin is necessary to connect chromosomes to the mitotic spindle, ensuring accurate chromosome segregation. This connecting function of the kinetochore presents multiple internal and external structural challenges. A microtubule interacting outer kinetochore and centromeric chromatin interacting inner kinetochore effectively confront forces from the external spindle and centromere, respectively. While internally, special inner kinetochore proteins, defined as “linkers,” simultaneously interact with centromeric chromatin and the outer kinetochore to enable association with the mitotic spindle. With the ability to simultaneously interact with outer kinetochore components and centromeric chromatin, linker proteins such as centromere protein (CENP)-C or CENP-T in vertebrates and, additionally CENP-QOkp1-UAme1 in yeasts, also perform the function of force propagation within the kinetochore. Recent efforts have revealed an array of linker pathways strategies to effectively recruit the largely conserved outer kinetochore. In this review, we examine these linkages used to propagate force and recruit the outer kinetochore across evolution. Further, we look at their known regulatory pathways and implications on kinetochore structural diversity and plasticity.
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Pesenti ME, Raisch T, Conti D, Walstein K, Hoffmann I, Vogt D, Prumbaum D, Vetter IR, Raunser S, Musacchio A. Structure of the human inner kinetochore CCAN complex and its significance for human centromere organization. Mol Cell 2022; 82:2113-2131.e8. [PMID: 35525244 PMCID: PMC9235857 DOI: 10.1016/j.molcel.2022.04.027] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/01/2022] [Accepted: 04/22/2022] [Indexed: 11/24/2022]
Abstract
Centromeres are specialized chromosome loci that seed the kinetochore, a large protein complex that effects chromosome segregation. A 16-subunit complex, the constitutive centromere associated network (CCAN), connects between the specialized centromeric chromatin, marked by the histone H3 variant CENP-A, and the spindle-binding moiety of the kinetochore. Here, we report a cryo-electron microscopy structure of human CCAN. We highlight unique features such as the pseudo GTPase CENP-M and report how a crucial CENP-C motif binds the CENP-LN complex. The CCAN structure has implications for the mechanism of specific recognition of the CENP-A nucleosome. A model consistent with our structure depicts the CENP-C-bound nucleosome as connected to the CCAN through extended, flexible regions of CENP-C. An alternative model identifies both CENP-C and CENP-N as specificity determinants but requires CENP-N to bind CENP-A in a mode distinct from the classical nucleosome octamer.
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Affiliation(s)
- Marion E Pesenti
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Tobias Raisch
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Duccio Conti
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Kai Walstein
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Ingrid Hoffmann
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Dorothee Vogt
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Daniel Prumbaum
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Stefan Raunser
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstrasse, 45141 Essen, Germany.
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Allipra S, Anirudhan K, Shivanandan S, Raghunathan A, Maruthachalam R. The kinetochore protein NNF1 has a moonlighting role in the vegetative development of Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2022; 109:1064-1085. [PMID: 34850467 DOI: 10.1111/tpj.15614] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 11/25/2021] [Indexed: 06/13/2023]
Abstract
The kinetochore is a supramolecular protein complex assembled on the chromosomes, essential for faithful segregation of the genome during cell divisions. More than 100 proteins are known to constitute the eukaryotic kinetochore architecture, primarily identified using non-plant organisms. A majority of them are fast evolving and are under positive selection. Thus, functional characterization of the plant kinetochore proteins is limited as only a few conserved orthologs sharing sequence similarity with their animal counterparts have been examined. Here, we report the functional characterization of the Arabidopsis thaliana homolog of the yeast NNF1/human PMF1 outer kinetochore protein and show that it has both kinetochore and non-kinetochore functions in plant growth and development. Knockout of NNF1 causes embryo lethality implying its essential role in cell division. AtNNF1 interacts with MIS12 in Y2H and co-immunoprecipitation assays, confirming it is one of the constituents of the plant MIS12 complex. GFP-NNF1 localizes to the kinetochore, rescuing the embryo lethal nnf1-1-/- phenotype, but the rescued plants (GFP-NNF1nnf1-/- ) are dwarf, displaying hypomorphic phenotypes with no evidence of mitotic or meiotic segregation defects. GFP-NNF1nnf1-/- dwarf plants have reduced levels of endogenous polyamines, which are partially rescued to wild-type levels upon exogenous application of polyamines. Mutations in the putative leucine zipper-like binding motif of NNF1 gave rise to a dominant-negative tall plant phenotype reminiscent of constitutive gibberellic acid (GA) action. These contrasting hypomorphic dwarf and antimorphic tall phenotypes facilitated us to attribute a moonlighting role to Arabidopsis NNF1 affecting polyamine and GA metabolism apart from its primary role in kinetochores.
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Affiliation(s)
- Sreejith Allipra
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram (IISER TVM), Maruthamala PO, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Krishnapriya Anirudhan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram (IISER TVM), Maruthamala PO, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Siddharth Shivanandan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram (IISER TVM), Maruthamala PO, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Abhishek Raghunathan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram (IISER TVM), Maruthamala PO, Vithura, Thiruvananthapuram, Kerala, 695551, India
| | - Ravi Maruthachalam
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram (IISER TVM), Maruthamala PO, Vithura, Thiruvananthapuram, Kerala, 695551, India
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6
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Mehta G, Sanyal K, Abhishek S, Rajakumara E, Ghosh SK. Minichromosome maintenance proteins in eukaryotic chromosome segregation. Bioessays 2021; 44:e2100218. [PMID: 34841543 DOI: 10.1002/bies.202100218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 11/05/2021] [Accepted: 11/08/2021] [Indexed: 01/02/2023]
Abstract
Minichromosome maintenance (Mcm) proteins are well-known for their functions in DNA replication. However, their roles in chromosome segregation are yet to be reviewed in detail. Following the discovery in 1984, a group of Mcm proteins, known as the ARS-nonspecific group consisting of Mcm13, Mcm16-19, and Mcm21-22, were characterized as bonafide kinetochore proteins and were shown to play significant roles in the kinetochore assembly and high-fidelity chromosome segregation. This review focuses on the structure, function, and evolution of this group of Mcm proteins. Our in silico analysis of the physical interactors of these proteins reveals that they share non-overlapping functions despite being copurified in biochemically stable complexes. We have discussed the contrasting results reported in the literature and experimental strategies to address them. Taken together, this review focuses on the structure-function of the ARS-nonspecific Mcm proteins and their evolutionary flexibility to maintain genome stability in various organisms.
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Affiliation(s)
- Gunjan Mehta
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Kaustuv Sanyal
- Molecular Biology and Genetics Unit, Jawaharlal Nehru Center for Advanced Scientific Research, Bangalore, India
| | - Suman Abhishek
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Eerappa Rajakumara
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Telangana, India
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, India
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7
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Ferreira LT, Maiato H. Prometaphase. Semin Cell Dev Biol 2021; 117:52-61. [PMID: 34127384 DOI: 10.1016/j.semcdb.2021.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 11/28/2022]
Abstract
The establishment of a metaphase plate in which all chromosomes are attached to mitotic spindle microtubules and aligned at the cell equator is required for faithful chromosome segregation in metazoans. The achievement of this configuration relies on the precise coordination between several concurrent mechanisms that start upon nuclear envelope breakdown, mediate chromosome capture at their kinetochores during mitotic spindle assembly and culminate with the congression of all chromosomes to the spindle equator. This period is called 'prometaphase'. Because the nature of chromosome capture by mitotic spindle microtubules is error prone, the cell is provided of error correction mechanisms that sense and correct most erroneous kinetochore-microtubule attachments before committing to separate sister chromatids in anaphase. In this review, aimed for newcomers in the field, more than providing an exhaustive mechanistic coverage of each and every concurrent mechanism taking place during prometaphase, we provide an integrative overview of these processes that ultimately promote the subsequent faithful segregation of chromosomes during mitosis.
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Affiliation(s)
- Luísa T Ferreira
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Helder Maiato
- Chromosome Instability & Dynamics Group, i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal; Cell Division Group, Experimental Biology Unit, Department of Biomedicine, Faculdade de Medicina, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
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8
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Thakur J, Packiaraj J, Henikoff S. Sequence, Chromatin and Evolution of Satellite DNA. Int J Mol Sci 2021; 22:ijms22094309. [PMID: 33919233 PMCID: PMC8122249 DOI: 10.3390/ijms22094309] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/16/2021] [Accepted: 04/17/2021] [Indexed: 12/15/2022] Open
Abstract
Satellite DNA consists of abundant tandem repeats that play important roles in cellular processes, including chromosome segregation, genome organization and chromosome end protection. Most satellite DNA repeat units are either of nucleosomal length or 5–10 bp long and occupy centromeric, pericentromeric or telomeric regions. Due to high repetitiveness, satellite DNA sequences have largely been absent from genome assemblies. Although few conserved satellite-specific sequence motifs have been identified, DNA curvature, dyad symmetries and inverted repeats are features of various satellite DNAs in several organisms. Satellite DNA sequences are either embedded in highly compact gene-poor heterochromatin or specialized chromatin that is distinct from euchromatin. Nevertheless, some satellite DNAs are transcribed into non-coding RNAs that may play important roles in satellite DNA function. Intriguingly, satellite DNAs are among the most rapidly evolving genomic elements, such that a large fraction is species-specific in most organisms. Here we describe the different classes of satellite DNA sequences, their satellite-specific chromatin features, and how these features may contribute to satellite DNA biology and evolution. We also discuss how the evolution of functional satellite DNA classes may contribute to speciation in plants and animals.
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Affiliation(s)
- Jitendra Thakur
- Department of Biology, Emory University, Atlanta, GA 30322, USA;
- Correspondence:
| | - Jenika Packiaraj
- Department of Biology, Emory University, Atlanta, GA 30322, USA;
| | - Steven Henikoff
- Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA;
- Fred Hutchinson Cancer Research Center, Howard Hughes Medical Institute, Seattle, WA 98109, USA
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9
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Navarro AP, Cheeseman IM. Kinetochore assembly throughout the cell cycle. Semin Cell Dev Biol 2021; 117:62-74. [PMID: 33753005 DOI: 10.1016/j.semcdb.2021.03.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/29/2022]
Abstract
The kinetochore plays an essential role in facilitating chromosome segregation during cell division. This massive protein complex assembles onto the centromere of chromosomes and enables their attachment to spindle microtubules during mitosis. The kinetochore also functions as a signaling hub to regulate cell cycle progression, and is crucial to ensuring the fidelity of chromosome segregation. Despite the fact that kinetochores are large and robust molecular assemblies, they are also highly dynamic structures that undergo structural and organizational changes throughout the cell cycle. This review will highlight our current understanding of kinetochore structure and function, focusing on the dynamic processes that underlie kinetochore assembly.
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Affiliation(s)
- Alexandra P Navarro
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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10
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The right place at the right time: Aurora B kinase localization to centromeres and kinetochores. Essays Biochem 2021; 64:299-311. [PMID: 32406506 DOI: 10.1042/ebc20190081] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/21/2020] [Accepted: 04/28/2020] [Indexed: 12/18/2022]
Abstract
The fidelity of chromosome segregation during mitosis is intimately linked to the function of kinetochores, which are large protein complexes assembled at sites of centromeric heterochromatin on mitotic chromosomes. These key "orchestrators" of mitosis physically connect chromosomes to spindle microtubules and transduce forces through these connections to congress chromosomes and silence the spindle assembly checkpoint. Kinetochore-microtubule attachments are highly regulated to ensure that incorrect attachments are not prematurely stabilized, but instead released and corrected. The kinase activity of the centromeric protein Aurora B is required for kinetochore-microtubule destabilization during mitosis, but how the kinase acts on outer kinetochore substrates to selectively destabilize immature and erroneous attachments remains debated. Here, we review recent literature that sheds light on how Aurora B kinase is recruited to both centromeres and kinetochores and discuss possible mechanisms for how kinase interactions with substrates at distinct regions of mitotic chromosomes are regulated.
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11
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Ghodgaonkar-Steger M, Potocnjak M, Zimniak T, Fischböck-Halwachs J, Solis-Mezarino V, Singh S, Speljko T, Hagemann G, Drexler DJ, Witte G, Herzog F. C-Terminal Motifs of the MTW1 Complex Cooperatively Stabilize Outer Kinetochore Assembly in Budding Yeast. Cell Rep 2020; 32:108190. [PMID: 32997987 DOI: 10.1016/j.celrep.2020.108190] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 07/18/2020] [Accepted: 09/01/2020] [Indexed: 12/01/2022] Open
Abstract
Kinetochores are macromolecular protein assemblies at centromeres that mediate accurate chromosome segregation during cell division. The outer kinetochore KNL1SPC105, MIS12MTW1, and NDC80NDC80 complexes assemble the KMN network, which harbors the sites of microtubule binding and spindle assembly checkpoint signaling. The buildup of the KMN network that transmits microtubule pulling forces to budding yeast point centromeres is poorly understood. Here, we identify 225 inter-protein crosslinks by mass spectrometry on KMN complexes isolated from Saccharomyces cerevisiae that delineate the KMN subunit connectivity for outer kinetochore assembly. C-Terminal motifs of Nsl1 and Mtw1 recruit the SPC105 complex through Kre28, and both motifs aid tethering of the NDC80 complex by the previously reported Dsn1 C terminus. We show that a hub of three C-terminal MTW1 subunit motifs mediates the cooperative stabilization of the KMN network, which is augmented by a direct NDC80-SPC105 association.
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Affiliation(s)
- Medini Ghodgaonkar-Steger
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Mia Potocnjak
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Tomasz Zimniak
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Josef Fischböck-Halwachs
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Victor Solis-Mezarino
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Sylvia Singh
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Tea Speljko
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Götz Hagemann
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - David Jan Drexler
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Gregor Witte
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Franz Herzog
- Gene Center Munich and Department of Biochemistry, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany.
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12
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Hinshaw SM, Harrison SC. The Structural Basis for Kinetochore Stabilization by Cnn1/CENP-T. Curr Biol 2020; 30:3425-3431.e3. [DOI: 10.1016/j.cub.2020.06.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/03/2020] [Accepted: 06/05/2020] [Indexed: 12/22/2022]
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13
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Killinger K, Böhm M, Steinbach P, Hagemann G, Blüggel M, Jänen K, Hohoff S, Bayer P, Herzog F, Westermann S. Auto-inhibition of Mif2/CENP-C ensures centromere-dependent kinetochore assembly in budding yeast. EMBO J 2020; 39:e102938. [PMID: 32515113 PMCID: PMC7360964 DOI: 10.15252/embj.2019102938] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 04/27/2020] [Accepted: 05/12/2020] [Indexed: 11/28/2022] Open
Abstract
Kinetochores are chromatin‐bound multi‐protein complexes that allow high‐fidelity chromosome segregation during mitosis and meiosis. Kinetochore assembly is exclusively initiated at chromatin containing Cse4/CENP‐A nucleosomes. The molecular mechanisms ensuring that subcomplexes assemble efficiently into kinetochores only at centromeres, but not anywhere else, are incompletely understood. Here, we combine biochemical and genetic experiments to demonstrate that auto‐inhibition of the conserved kinetochore subunit Mif2/CENP‐C contributes to preventing unscheduled kinetochore assembly in budding yeast cells. We show that wild‐type Mif2 is attenuated in its ability to bind a key downstream component in the assembly pathway, the Mtw1 complex, and that addition of Cse4 nucleosomes overcomes this inhibition. By exchanging the N‐terminus of Mif2 with its functional counterpart from Ame1/CENP‐U, we have created a Mif2 mutant which bypasses the Cse4 requirement for Mtw1 binding in vitro, thereby shortcutting kinetochore assembly. Expression of this Mif2 mutant in cells leads to mis‐localization of the Mtw1 complex and causes pronounced chromosome segregation defects. We propose that auto‐inhibition of Mif2/CENP‐C constitutes a key concept underlying the molecular logic of kinetochore assembly.
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Affiliation(s)
- Kerstin Killinger
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Miriam Böhm
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Philine Steinbach
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Götz Hagemann
- Department of Biochemistry, Gene Center, Ludwig-Maximilians-Universität München, München, Germany
| | - Mike Blüggel
- Structural and Medicinal Biochemistry, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Karolin Jänen
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Simone Hohoff
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Peter Bayer
- Structural and Medicinal Biochemistry, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
| | - Franz Herzog
- Department of Biochemistry, Gene Center, Ludwig-Maximilians-Universität München, München, Germany
| | - Stefan Westermann
- Department of Molecular Genetics, Faculty of Biology, Center of Medical Biotechnology, University of Duisburg-Essen, Essen, Germany
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14
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Dbf4-Dependent Kinase (DDK)-Mediated Proteolysis of CENP-A Prevents Mislocalization of CENP-A in Saccharomyces cerevisiae. G3-GENES GENOMES GENETICS 2020; 10:2057-2068. [PMID: 32295767 PMCID: PMC7263675 DOI: 10.1534/g3.120.401131] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The evolutionarily conserved centromeric histone H3 variant (Cse4 in budding yeast, CENP-A in humans) is essential for faithful chromosome segregation. Mislocalization of CENP-A to non-centromeric chromatin contributes to chromosomal instability (CIN) in yeast, fly, and human cells and CENP-A is highly expressed and mislocalized in cancers. Defining mechanisms that prevent mislocalization of CENP-A is an area of active investigation. Ubiquitin-mediated proteolysis of overexpressed Cse4 (GALCSE4) by E3 ubiquitin ligases such as Psh1 prevents mislocalization of Cse4, and psh1 Δ strains display synthetic dosage lethality (SDL) with GALCSE4 We previously performed a genome-wide screen and identified five alleles of CDC7 and DBF4 that encode the Dbf4-dependent kinase (DDK) complex, which regulates DNA replication initiation, among the top twelve hits that displayed SDL with GALCSE4 We determined that cdc7 -7 strains exhibit defects in ubiquitin-mediated proteolysis of Cse4 and show mislocalization of Cse4 Mutation of MCM5 (mcm5 -bob1) bypasses the requirement of Cdc7 for replication initiation and rescues replication defects in a cdc7 -7 strain. We determined that mcm5 -bob1 does not rescue the SDL and defects in proteolysis of GALCSE4 in a cdc7 -7 strain, suggesting a DNA replication-independent role for Cdc7 in Cse4 proteolysis. The SDL phenotype, defects in ubiquitin-mediated proteolysis, and the mislocalization pattern of Cse4 in a cdc7 -7 psh1 Δ strain were similar to that of cdc7 -7 and psh1 Δ strains, suggesting that Cdc7 regulates Cse4 in a pathway that overlaps with Psh1 Our results define a DNA replication initiation-independent role of DDK as a regulator of Psh1-mediated proteolysis of Cse4 to prevent mislocalization of Cse4.
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15
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Talbert PB, Henikoff S. What makes a centromere? Exp Cell Res 2020; 389:111895. [PMID: 32035948 DOI: 10.1016/j.yexcr.2020.111895] [Citation(s) in RCA: 96] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Revised: 01/18/2020] [Accepted: 02/05/2020] [Indexed: 12/26/2022]
Abstract
Centromeres are the eukaryotic chromosomal sites at which the kinetochore forms and attaches to spindle microtubules to orchestrate chromosomal segregation in mitosis and meiosis. Although centromeres are essential for cell division, their sequences are not conserved and evolve rapidly. Centromeres vary dramatically in size and organization. Here we categorize their diversity and explore the evolutionary forces shaping them. Nearly all centromeres favor AT-rich DNA that is gene-free and transcribed at a very low level. Repair of frequent centromere-proximal breaks probably contributes to their rapid sequence evolution. Point centromeres are only ~125 bp and are specified by common protein-binding motifs, whereas short regional centromeres are 1-5 kb, typically have unique sequences, and may have pericentromeric repeats adapted to facilitate centromere clustering. Transposon-rich centromeres are often ~100-300 kb and are favored by RNAi machinery that silences transposons, by suppression of meiotic crossovers at centromeres, and by the ability of some transposons to target centromeres. Megabase-length satellite centromeres arise in plants and animals with asymmetric female meiosis that creates centromere competition, and favors satellite monomers one or two nucleosomes in length that position and stabilize centromeric nucleosomes. Holocentromeres encompass the length of a chromosome and may differ dramatically between mitosis and meiosis. We propose a model in which low level transcription of centromeres facilitates the formation of non-B DNA that specifies centromeres and promotes loading of centromeric nucleosomes.
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Affiliation(s)
- Paul B Talbert
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA, 98109, USA
| | - Steven Henikoff
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave N, Seattle, WA, 98109, USA.
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16
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Zhang Y, Zhao C, Cao B, Ye J, Huang H, Hu L, Tian W, He X. Structural insights into the intramolecular interactions of centromere protein CENP-I. J Mol Recognit 2020; 33:e2837. [PMID: 32017295 DOI: 10.1002/jmr.2837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/05/2020] [Accepted: 01/14/2020] [Indexed: 01/04/2023]
Abstract
In mitosis, the accurate segregation of sister chromosomes relies on kinetochore, a multiple subunits complex assembled on centromere of each sister chromosome. As a core component of inner kinetochore, CENP-I plays important functions to mediate kinetochore assembly and supports the faithful chromosome segregation. The structures of the N-terminus and C-terminus of CENP-I homologs in complex with CENP-H/K have been reported, respectively. Unfortunately, the intramolecular interactions of CENP-I are poorly understood, and how CENP-I interacts with CENP-M remains unknown. Here, we verified a unique helix α11, which forms the intramolecular interactions with N-terminal HEAT repeats in fungal CENP-I. Deletion of the helix α11 exposed the hydrophobic surface and resulted in the in vitro protein aggregation of N-terminal HEAT repeats of fungal CENP-I. The corresponding helix and its intramolecular interaction are highly conserved in human CENP-I. Deletion of the corresponding helix in human CENP-I dramatically reduced the functional activity to interact with CENP-H and CENP-M. Mutations of the conserved residues on the helix in human CENP-I significantly weakened the binding to CENP-M, but not CENP-H, in HeLa cells. Therefore, our findings for the first time unveiled a conserved helix of CENP-I, which is important for the intramolecular interaction and function, and would be helpful for understanding the structure basis of how CENP-I mediates the kinetochore assembly during cell cycle and mitosis.
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Affiliation(s)
- Yu Zhang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Congcong Zhao
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Beibei Cao
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Jingjing Ye
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Hao Huang
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Liqiao Hu
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Tian
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaojing He
- Key Laboratory of Molecular Biophysics of the Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
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17
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Sankaranarayanan SR, Ianiri G, Coelho MA, Reza MH, Thimmappa BC, Ganguly P, Vadnala RN, Sun S, Siddharthan R, Tellgren-Roth C, Dawson TL, Heitman J, Sanyal K. Loss of centromere function drives karyotype evolution in closely related Malassezia species. eLife 2020; 9:e53944. [PMID: 31958060 PMCID: PMC7025860 DOI: 10.7554/elife.53944] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
Genomic rearrangements associated with speciation often result in variation in chromosome number among closely related species. Malassezia species show variable karyotypes ranging between six and nine chromosomes. Here, we experimentally identified all eight centromeres in M. sympodialis as 3-5-kb long kinetochore-bound regions that span an AT-rich core and are depleted of the canonical histone H3. Centromeres of similar sequence features were identified as CENP-A-rich regions in Malassezia furfur, which has seven chromosomes, and histone H3 depleted regions in Malassezia slooffiae and Malassezia globosa with nine chromosomes each. Analysis of synteny conservation across centromeres with newly generated chromosome-level genome assemblies suggests two distinct mechanisms of chromosome number reduction from an inferred nine-chromosome ancestral state: (a) chromosome breakage followed by loss of centromere DNA and (b) centromere inactivation accompanied by changes in DNA sequence following chromosome-chromosome fusion. We propose that AT-rich centromeres drive karyotype diversity in the Malassezia species complex through breakage and inactivation.
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Affiliation(s)
- Sundar Ram Sankaranarayanan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Marco A Coelho
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Md Hashim Reza
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Bhagya C Thimmappa
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Promit Ganguly
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | | | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | | | - Christian Tellgren-Roth
- National Genomics Infrastructure, Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala UniversityUppsalaSweden
| | - Thomas L Dawson
- Skin Research Institute Singapore, Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
- Department of Drug Discovery, Medical University of South Carolina, School of PharmacyCharlestonUnited States
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
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18
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Dhatchinamoorthy K, Unruh JR, Lange JJ, Levy M, Slaughter BD, Gerton JL. The stoichiometry of the outer kinetochore is modulated by microtubule-proximal regulatory factors. J Cell Biol 2019; 218:2124-2135. [PMID: 31118239 PMCID: PMC6605801 DOI: 10.1083/jcb.201810070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 04/11/2019] [Accepted: 05/02/2019] [Indexed: 12/16/2022] Open
Abstract
Dhatchinamoorthy et al. suggest the stoichiometry of outer submodules of the budding yeast kinetochore is strongly influenced by factors at the kinetochore–microtubule interface such as Fin1 and Dam1. Outer kinetochore stoichiometry is remarkably plastic and responsive to microtubule-proximal regulation. The kinetochore is a large molecular machine that attaches chromosomes to microtubules and facilitates chromosome segregation. The kinetochore includes submodules that associate with the centromeric DNA and submodules that attach to microtubules. Additional copies of several submodules of the kinetochore are added during anaphase, including the microtubule binding module Ndc80. While the factors governing plasticity are not known, they could include regulation based on microtubule–kinetochore interactions. We report that Fin1 localizes to the microtubule-proximal edge of the kinetochore cluster during anaphase based on single-particle averaging of super-resolution images. Fin1 is required for the assembly of normal levels of Dam1 and Ndc80 submodules. Levels of Ndc80 further depend on the Dam1 microtubule binding complex. Our results suggest the stoichiometry of outer kinetochore submodules is strongly influenced by factors at the kinetochore–microtubule interface such as Fin1 and Dam1, and phosphorylation by cyclin-dependent kinase. Outer kinetochore stoichiometry is remarkably plastic and responsive to microtubule-proximal regulation.
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Affiliation(s)
- Karthik Dhatchinamoorthy
- Stowers Institute for Medical Research, Kansas City, MO.,Open University, Milton Keynes, England, UK
| | - Jay R Unruh
- Stowers Institute for Medical Research, Kansas City, MO
| | | | | | | | - Jennifer L Gerton
- Stowers Institute for Medical Research, Kansas City, MO .,Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, KS
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19
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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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20
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Mishra PK, Olafsson G, Boeckmann L, Westlake TJ, Jowhar ZM, Dittman LE, Baker RE, D’Amours D, Thorpe PH, Basrai MA. Cell cycle-dependent association of polo kinase Cdc5 with CENP-A contributes to faithful chromosome segregation in budding yeast. Mol Biol Cell 2019; 30:1020-1036. [PMID: 30726152 PMCID: PMC6589903 DOI: 10.1091/mbc.e18-09-0584] [Citation(s) in RCA: 14] [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: 09/18/2018] [Revised: 01/04/2019] [Accepted: 01/30/2019] [Indexed: 12/18/2022] Open
Abstract
Evolutionarily conserved polo-like kinase, Cdc5 (Plk1 in humans), associates with kinetochores during mitosis; however, the role of cell cycle-dependent centromeric ( CEN) association of Cdc5 and its substrates that exclusively localize to the kinetochore have not been characterized. Here we report that evolutionarily conserved CEN histone H3 variant, Cse4 (CENP-A in humans), is a substrate of Cdc5, and that the cell cycle-regulated association of Cse4 with Cdc5 is required for cell growth. Cdc5 contributes to Cse4 phosphorylation in vivo and interacts with Cse4 in mitotic cells. Mass spectrometry analysis of in vitro kinase assays showed that Cdc5 phosphorylates nine serine residues clustered within the N-terminus of Cse4. Strains with cse4-9SA exhibit increased errors in chromosome segregation, reduced levels of CEN-associated Mif2 and Mcd1/Scc1 when combined with a deletion of MCM21. Moreover, the loss of Cdc5 from the CEN chromatin contributes to defects in kinetochore integrity and reduction in CEN-associated Cse4. The cell cycle-regulated association of Cdc5 with Cse4 is essential for cell viability as constitutive association of Cdc5 with Cse4 at the kinetochore leads to growth defects. In summary, our results have defined a role for Cdc5-mediated Cse4 phosphorylation in faithful chromosome segregation.
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Affiliation(s)
- Prashant K. Mishra
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Gudjon Olafsson
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, United Kingdom
| | - Lars Boeckmann
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Timothy J. Westlake
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Ziad M. Jowhar
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Lauren E. Dittman
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Richard E. Baker
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01655
| | - Damien D’Amours
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1N 6N5, Canada
| | - Peter H. Thorpe
- School of Biological and Chemical Sciences, Queen Mary University of London, London E1 4NS, United Kingdom
| | - Munira A. Basrai
- Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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21
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Reconstitution of a 26-Subunit Human Kinetochore Reveals Cooperative Microtubule Binding by CENP-OPQUR and NDC80. Mol Cell 2018; 71:923-939.e10. [PMID: 30174292 PMCID: PMC6162344 DOI: 10.1016/j.molcel.2018.07.038] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/04/2018] [Accepted: 07/25/2018] [Indexed: 12/15/2022]
Abstract
The approximately thirty core subunits of kinetochores assemble on centromeric chromatin containing the histone H3 variant CENP-A and connect chromosomes with spindle microtubules. The chromatin proximal 16-subunit CCAN (constitutive centromere associated network) creates a mechanically stable bridge between CENP-A and the kinetochore’s microtubule-binding machinery, the 10-subunit KMN assembly. Here, we reconstituted a stoichiometric 11-subunit human CCAN core that forms when the CENP-OPQUR complex binds to a joint interface on the CENP-HIKM and CENP-LN complexes. The resulting CCAN particle is globular and connects KMN and CENP-A in a 26-subunit recombinant particle. The disordered, basic N-terminal tail of CENP-Q binds microtubules and promotes accurate chromosome alignment, cooperating with KMN in microtubule binding. The N-terminal basic tail of the NDC80 complex, the microtubule-binding subunit of KMN, can functionally replace the CENP-Q tail. Our work dissects the connectivity and architecture of CCAN and reveals unexpected functional similarities between CENP-OPQUR and the NDC80 complex. The kinetochore CENP-OPQUR complex is reconstituted and functionally dissected A kinetochore particle with 26 subunits and defined stoichiometry is reconstituted EM structure of an 11-subunit inner kinetochore complex reveals globular shape CENP-Q and the Ndc80 complex bind microtubules cooperatively
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22
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Dhatchinamoorthy K, Mattingly M, Gerton JL. Regulation of kinetochore configuration during mitosis. Curr Genet 2018; 64:1197-1203. [DOI: 10.1007/s00294-018-0841-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 04/19/2018] [Accepted: 04/20/2018] [Indexed: 12/15/2022]
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23
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Hoischen C, Yavas S, Wohland T, Diekmann S. CENP-C/H/I/K/M/T/W/N/L and hMis12 but not CENP-S/X participate in complex formation in the nucleoplasm of living human interphase cells outside centromeres. PLoS One 2018; 13:e0192572. [PMID: 29509805 PMCID: PMC5839545 DOI: 10.1371/journal.pone.0192572] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 01/25/2018] [Indexed: 12/25/2022] Open
Abstract
Kinetochore proteins assemble onto centromeric chromatin and regulate DNA segregation during cell division. The inner kinetochore proteins bind centromeres while most outer kinetochore proteins assemble at centromeres during mitosis, connecting the complex to microtubules. Here, we measured the co-migration between protein pairs of the constitutive centromere associated network (CCAN) and hMis12 complexes by fluorescence cross-correlation spectroscopy (FCCS) in the nucleoplasm outside centromeres in living human interphase cells. FCCS is a method that can tell if in living cells two differently fluorescently labelled molecules migrate independently, or co-migrate and thus are part of one and the same soluble complex. We also determined the apparent dissociation constants (Kd) of the hetero-dimers CENP-T/W and CENP-S/X. We measured co-migration between CENP-K and CENP-T as well as between CENP-M and CENP-T but not between CENP-T/W and CENP-S/X. Furthermore, CENP-C co-migrated with CENP-H, and CENP-K with CENP-N as well as with CENP-L. Thus, in the nucleoplasm outside centromeres, a large fraction of the CENP-H/I/K/M proteins interact with CENP-C, CENP-N/L and CENP-T/W but not with CENP-S/X. Our FCCS analysis of the Mis12 complex showed that hMis12, Nsl1, Dsn1 and Nnf1 also form a complex outside centromeres of which at least hMis12 associated with the CENP-C/H/I/K/M/T/W/N/L complex.
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Affiliation(s)
- Christian Hoischen
- Molecular Biology, Leibniz Institute on Aging-Friz-Lipmann-Institute (FLI), Jena, Germany
| | - Sibel Yavas
- Departments of Biological Sciences and Chemistry and Centre of Bioimaging Sciences, Lee Wee Kheng Buildung, National University of Singapore, Singapore, Singapore
| | - Thorsten Wohland
- Departments of Biological Sciences and Chemistry and Centre of Bioimaging Sciences, Lee Wee Kheng Buildung, National University of Singapore, Singapore, Singapore
| | - Stephan Diekmann
- Molecular Biology, Leibniz Institute on Aging-Friz-Lipmann-Institute (FLI), Jena, Germany
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24
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Mishra PK, Thapa KS, Chen P, Wang S, Hazbun TR, Basrai MA. Budding yeast CENP-A Cse4 interacts with the N-terminus of Sgo1 and regulates its association with centromeric chromatin. Cell Cycle 2018; 17:11-23. [PMID: 28980861 DOI: 10.1080/15384101.2017.1380129] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Shugoshin is an evolutionarily conserved protein, which is involved in tension sensing on mitotic chromosomes, kinetochore biorientation, and protection of centromeric (CEN) cohesin for faithful chromosome segregation. Interaction of the C-terminus of Sgo1 with phosphorylated histone H2A regulates its association with CEN and pericentromeric (peri-CEN) chromatin, whereas mutations in histone H3 selectively compromise the association of Sgo1 with peri-CEN but not CEN chromatin. Given that histone H3 is absent from CEN and is replaced by a histone H3 variant CENP-ACse4, we investigated if CENP-ACse4 interacts with Sgo1 and promotes its association with the CEN chromatin. In this study, we found that Sgo1 interacts with CENP-ACse4 in vivo and in vitro. The N-terminus coiled-coil domain of Sgo1 without the C-terminus (sgo1-NT) is sufficient for its interaction with CENP-ACse4, association with CEN but not the peri-CEN, and this CEN association is cell cycle dependent with maximum enrichment in mitosis. In agreement with the role of CENP-ACse4 in CEN maintenance of Sgo1, depletion of CENP-ACse4 results in the loss of Sgo1 and sgo1-NT from the CEN chromatin. The N-terminus of Sgo1 is required for genome stability as a mutant lacking the N-terminus (sgo1-CT) exhibits increased chromosome missegregation when compared to a sgo1-NT mutant. In summary, our results define a novel role for the N-terminus of Sgo1 in CENP-ACse4 mediated recruitment of Sgo1 to CEN chromatin for faithful chromosome segregation.
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Affiliation(s)
- Prashant K Mishra
- a Genetics Branch , National Cancer Institute , National Institutes of Health , Bethesda , MD , USA
| | - Kriti S Thapa
- b Purdue University , Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University Center for Cancer Research (PUCCR) , West Lafayette , IN , USA
| | - Panyue Chen
- b Purdue University , Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University Center for Cancer Research (PUCCR) , West Lafayette , IN , USA
| | - Suyu Wang
- b Purdue University , Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University Center for Cancer Research (PUCCR) , West Lafayette , IN , USA
| | - Tony R Hazbun
- b Purdue University , Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University Center for Cancer Research (PUCCR) , West Lafayette , IN , USA
| | - Munira A Basrai
- a Genetics Branch , National Cancer Institute , National Institutes of Health , Bethesda , MD , USA
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25
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Phosphorylation of CENP-C by Aurora B facilitates kinetochore attachment error correction in mitosis. Proc Natl Acad Sci U S A 2017; 114:E10667-E10676. [PMID: 29180432 PMCID: PMC5740674 DOI: 10.1073/pnas.1710506114] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Kinetochores are large protein networks located on centromeres that mediate chromosome segregation during mitosis and maintain genomic stability. Mis12 complex (Mis12C) functions as a scaffold that targets Ndc80 and Knl1 complexes to the centromere by associating with CENP-C. Here, we provide insights into the molecular mechanism underlying the CENP-C–dependent kinetochore recruitment of Mis12C, which is negatively regulated by Aurora B-dependent CENP-C phosphorylation. Replacement of Schizosaccharomyces pombe Cnp3 with a phosphorylation-mimicking mutant, Cnp3T28E, results in defective chromosome segregation caused by improper kinetochore assembly. These findings indicate that Aurora B-dependent phosphorylation of CENP-C plays a role in interrupting the connection between the inner and outer kinetochore and is thus involved in the error correction/spindle assembly checkpoint pathway to prevent chromosome missegregation during mitosis. Kinetochores are superprotein complexes that orchestrate chromosome segregation via a dynamic interaction with spindle microtubules. A physical connection between CENP-C and the Mis12–Ndc80–Knl1 (KMN) protein network is an important pathway that is used to assemble kinetochores on CENP-A nucleosomes. Multiple outer kinetochore components are phosphorylated by Aurora B kinase to activate the spindle assembly checkpoint (SAC) and to ensure accurate chromosome segregation. However, it is unknown whether Aurora B can phosphorylate inner kinetochore components to facilitate proper mitotic chromosome segregation. Here, we reported the structure of the fission yeast Schizosaccharomyces pombe Mis12–Nnf1 complex and showed that N-terminal residues 26–50 in Cnp3 (the CENP-C homolog of S. pombe) are responsible for interacting with the Mis12 complex. Interestingly, Thr28 of Cnp3 is a substrate of Ark1 (the Aurora B homolog of S. pombe), and phosphorylation impairs the interaction between the Cnp3 and Mis12 complex. The expression of a phosphorylation-mimicking Cnp3 mutant results in defective chromosome segregation due to improper kinetochore assembly. These results establish a previously uncharacterized regulatory mechanism involved in CENP-C–Mis12-facilitated kinetochore attachment error correction to ensure accurate chromosome segregation during mitosis.
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26
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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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Üretmen Kagıalı ZC, Şentürk A, Özkan Küçük NE, Qureshi MH, Özlü N. Proteomics in Cell Division. Proteomics 2017; 17. [PMID: 28548456 DOI: 10.1002/pmic.201600100] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 04/07/2017] [Indexed: 11/08/2022]
Abstract
Cell division requires a coordinated action of the cell cycle machinery, cytoskeletal elements, chromosomes, and membranes. Cell division studies have greatly benefitted from the mass spectrometry (MS)-based proteomic approaches for probing the biochemistry of highly dynamic complexes and their coordination with each other as a cell progresses into division. In this review, the authors first summarize a wide-range of proteomic studies that focus on the identification of sub-cellular components/protein complexes of the cell division machinery including kinetochores, mitotic spindle, midzone, and centrosomes. The authors also highlight MS-based large-scale analyses of the cellular components that are largely understudied during cell division such as the cell surface and lipids. Then, the authors focus on posttranslational modification analyses, especially phosphorylation and the resulting crosstalk with other modifications as a cell undergoes cell division. Combining proteomic approaches that probe the biochemistry of cell division components with functional genomic assays will lead to breakthroughs toward a systems-level understanding of cell division.
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Affiliation(s)
| | - Aydanur Şentürk
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
| | | | - Mohammad Haroon Qureshi
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey.,Biomedical Sciences and Engineering, Koç University, Istanbul, Turkey
| | - Nurhan Özlü
- Department of Molecular Biology and Genetics, Koç University, Istanbul, Turkey
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28
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Wu W, Wu F, Wang Z, Di J, Yang J, Gao P, Jiang B, Su X. CENPH Inhibits Rapamycin Sensitivity by Regulating GOLPH3-dependent mTOR Signaling Pathway in Colorectal Cancer. J Cancer 2017; 8:2163-2172. [PMID: 28819418 PMCID: PMC5560133 DOI: 10.7150/jca.19940] [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: 03/06/2017] [Accepted: 04/25/2017] [Indexed: 12/29/2022] Open
Abstract
Background: Centromere protein H (CENPH) is known as a fundamental component of the active centromere complex, and its overexpression is correlated with poor prognosis in various solid tumors. mTOR inhibitor rapamycin has been shown to possess antitumor activity, as well as prevent intestinal tumorigenesis. However, the prognostic value of CENPH in colorectal cancer (CRC) and the role of CENPH in rapamycin sensitivity remain unknown. Materials and methods: The effect of CENPH on the cell proliferation, clonogenicity, and cell response to rapamycin in CRC were evaluated by MTT and/or colony formation assays. For the underlying mechanisms, the interaction between CENPH and GOLPH3 were detected by co-immunoprecipitation, GST pull-down, and His-tag pull-down assays, as well as the laser scanning confocal microscopy. The status of kinases in mTOR signaling was determined by Western blot. Finally, the clinical significance of CENPH was analyzed using public CRC datasets with CENPH transcripts and clinical information. Results: CENPH inhibited CRC malignant phenotypes, conferred reduced sensitivity to rapamycin, and attenuated both mTORC1 and mTORC2 in mTOR signaling pathway through the interaction with golgi phosphoprotein 3 (GOLPH3), which has been identified as a potential oncogene and modulates the response to rapamycin. Moreover, elevated levels of CENPH were detected in CRC tissues, compared with normal colorectal tissues. High levels of CENPH expression gradually decreased according to CRC tumor stages. Patients with high CENPH expression had favorable survival. Conclusions: Our results suggest that CENPH inhibits rapamycin sensitivity by regulating GOLPH3 dependent mTOR pathway. High CENPH expression is associated with better prognosis in CRC patients. Taken together, CENPH may serve as a potential predictor for rapamycin sensitivity and therapeutic target for CRC patients.
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Affiliation(s)
- Wei Wu
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Fan Wu
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Zaozao Wang
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Jiabo Di
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Jie Yang
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Pin Gao
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Beihai Jiang
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
| | - Xiangqian Su
- Key laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Gastrointestinal Surgery IV, Peking University Cancer Hospital & Institute, Beijing 100142, China
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29
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Abstract
Centromeres are essential for cell division and growth in all eukaryotes, and knowledge of their sequence and structure guides the development of artificial chromosomes for functional cellular biology studies. Centromeric proteins are conserved among eukaryotes; however, centromeric DNA sequences are highly variable. We combined forward and reverse genetic approaches with chromatin immunoprecipitation to identify centromeres of the model diatom Phaeodactylum tricornutum We observed 25 unique centromere sequences typically occurring once per chromosome, a finding that helps to resolve nuclear genome organization and indicates monocentric regional centromeres. Diatom centromere sequences contain low-GC content regions but lack repeats or other conserved sequence features. Native and foreign sequences with similar GC content to P. tricornutum centromeres can maintain episomes and recruit the diatom centromeric histone protein CENH3, suggesting nonnative sequences can also function as diatom centromeres. Thus, simple sequence requirements may enable DNA from foreign sources to persist in the nucleus as extrachromosomal episomes, revealing a potential mechanism for organellar and foreign DNA acquisition.
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30
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Abstract
Kinetochores are complex multiprotein machines that link chromosomes to dynamic microtubules for chromosome segregation. Two studies in Cell reveal the structure of the human MIS12 and budding yeast MIND kinetochore complexes and the regulatory mechanisms that enable them to link chromosomes to microtubules during mitosis.
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Affiliation(s)
- Rene Ladurner
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - Aaron F Straight
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA.
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31
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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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32
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Zasadzińska E, Foltz DR. Orchestrating the Specific Assembly of Centromeric Nucleosomes. PROGRESS IN MOLECULAR AND SUBCELLULAR BIOLOGY 2017; 56:165-192. [PMID: 28840237 DOI: 10.1007/978-3-319-58592-5_7] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Centromeres are chromosomal loci that are defined epigenetically in most eukaryotes by incorporation of a centromere-specific nucleosome in which the canonical histone H3 variant is replaced by Centromere Protein A (CENP-A). Therefore, the assembly and propagation of centromeric nucleosomes are critical for maintaining centromere identify and ensuring genomic stability. Centromeres direct chromosome segregation (during mitosis and meiosis) by recruiting the constitutive centromere-associated network of proteins throughout the cell cycle that in turn recruits the kinetochore during mitosis. Assembly of centromere-specific nucleosomes in humans requires the dedicated CENP-A chaperone HJURP, and the Mis18 complex to couple the deposition of new CENP-A to the site of the pre-existing centromere, which is essential for maintaining centromere identity. Human CENP-A deposition occurs specifically in early G1, into pre-existing chromatin, and several additional chromatin-associated complexes regulate CENP-A nucleosome deposition and stability. Here we review the current knowledge on how new CENP-A nucleosomes are assembled selectively at the existing centromere in different species and how this process is controlled to ensure stable epigenetic inheritance of the centromere.
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Affiliation(s)
- Ewelina Zasadzińska
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA
| | - Daniel R Foltz
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA, 22908, USA. .,Department of Biochemistry and Molecular Genetics, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA. .,Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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33
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Sandmann M, Talbert P, Demidov D, Kuhlmann M, Rutten T, Conrad U, Lermontova I. Targeting of Arabidopsis KNL2 to Centromeres Depends on the Conserved CENPC-k Motif in Its C Terminus. THE PLANT CELL 2017; 29:144-155. [PMID: 28062749 PMCID: PMC5304352 DOI: 10.1105/tpc.16.00720] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 12/14/2016] [Accepted: 01/04/2017] [Indexed: 05/03/2023]
Abstract
KINETOCHORE NULL2 (KNL2) is involved in recognition of centromeres and in centromeric localization of the centromere-specific histone cenH3. Our study revealed a cenH3 nucleosome binding CENPC-k motif at the C terminus of Arabidopsis thaliana KNL2, which is conserved among a wide spectrum of eukaryotes. Centromeric localization of KNL2 is abolished by deletion of the CENPC-k motif and by mutating single conserved amino acids, but can be restored by insertion of the corresponding motif of Arabidopsis CENP-C. We showed by electrophoretic mobility shift assay that the C terminus of KNL2 binds DNA sequence-independently and interacts with the centromeric transcripts in vitro. Chromatin immunoprecipitation with anti-KNL2 antibodies indicated that in vivo KNL2 is preferentially associated with the centromeric repeat pAL1 Complete deletion of the CENPC-k motif did not influence its ability to interact with DNA in vitro. Therefore, we suggest that KNL2 recognizes centromeric nucleosomes, similar to CENP-C, via the CENPC-k motif and binds adjoining DNA.
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Affiliation(s)
- Michael Sandmann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
| | - Paul Talbert
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
| | - Dmitri Demidov
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
| | - Markus Kuhlmann
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
| | - Twan Rutten
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
| | - Udo Conrad
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
| | - Inna Lermontova
- Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) Gatersleben, D-06466 Stadt Seeland, Germany
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CENP-A and H3 Nucleosomes Display a Similar Stability to Force-Mediated Disassembly. PLoS One 2016; 11:e0165078. [PMID: 27820823 PMCID: PMC5098787 DOI: 10.1371/journal.pone.0165078] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 10/05/2016] [Indexed: 12/12/2022] Open
Abstract
Centromere-specific nucleosomes are a central feature of the kinetochore complex during mitosis, in which microtubules exert pulling and pushing forces upon the centromere. CENP-A nucleosomes have been assumed to be structurally unique, thereby providing resilience under tension relative to their H3 canonical counterparts. Here, we directly test this hypothesis by subjecting CENP-A and H3 octameric nucleosomes, assembled on random or on centromeric DNA sequences, to varying amounts of applied force by using single-molecule magnetic tweezers. We monitor individual disassembly events of CENP-A and H3 nucleosomes. Regardless of the DNA sequence, the force-mediated disassembly experiments for CENP-A and H3 nucleosomes demonstrate similar rupture forces, life time residency and disassembly steps. From these experiments, we conclude that CENP-A does not, by itself, contribute unique structural features to the nucleosome that lead to a significant resistance against force-mediated disruption. The data present insights into the mechanistic basis for how CENP-A nucleosomes might contribute to the structural foundation of the centromere in vivo.
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35
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Dimitrova YN, Jenni S, Valverde R, Khin Y, Harrison SC. Structure of the MIND Complex Defines a Regulatory Focus for Yeast Kinetochore Assembly. Cell 2016; 167:1014-1027.e12. [PMID: 27881300 PMCID: PMC5856483 DOI: 10.1016/j.cell.2016.10.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/02/2016] [Accepted: 10/03/2016] [Indexed: 11/25/2022]
Abstract
Kinetochores connect centromeric nucleosomes with mitotic-spindle microtubules through conserved, cross-interacting protein subassemblies. In budding yeast, the heterotetrameric MIND complex (Mtw1, Nnf1, Nsl1, Dsn1), ortholog of the metazoan Mis12 complex, joins the centromere-proximal components, Mif2 and COMA, with the principal microtubule-binding component, the Ndc80 complex (Ndc80C). We report the crystal structure of Kluyveromyces lactis MIND and examine its partner interactions, to understand the connection from a centromeric nucleosome to a much larger microtubule. MIND resembles an elongated, asymmetric Y; two globular heads project from a coiled-coil shaft. An N-terminal extension of Dsn1 from one head regulates interactions of the other head, blocking binding of Mif2 and COMA. Dsn1 phosphorylation by Ipl1/Aurora B relieves this autoinhibition, enabling MIND to join an assembling kinetochore. A C-terminal extension of Dsn1 recruits Ndc80C to the opposite end of the shaft. The structure and properties of MIND show how it integrates phospho-regulatory inputs for kinetochore assembly and disassembly.
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Affiliation(s)
- Yoana N Dimitrova
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Simon Jenni
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Roberto Valverde
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Yadana Khin
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115, USA; Howard Hughes Medical Institute, 250 Longwood Avenue, Boston, MA 02115, USA.
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36
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Petrovic A, Keller J, Liu Y, Overlack K, John J, Dimitrova YN, Jenni S, van Gerwen S, Stege P, Wohlgemuth S, Rombaut P, Herzog F, Harrison SC, Vetter IR, Musacchio A. Structure of the MIS12 Complex and Molecular Basis of Its Interaction with CENP-C at Human Kinetochores. Cell 2016; 167:1028-1040.e15. [PMID: 27881301 PMCID: PMC5101189 DOI: 10.1016/j.cell.2016.10.005] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/16/2016] [Accepted: 10/03/2016] [Indexed: 01/14/2023]
Abstract
Kinetochores, multisubunit protein assemblies, connect chromosomes to spindle microtubules to promote chromosome segregation. The 10-subunit KMN assembly (comprising KNL1, MIS12, and NDC80 complexes, designated KNL1C, MIS12C, and NDC80C) binds microtubules and regulates mitotic checkpoint function through NDC80C and KNL1C, respectively. MIS12C, on the other hand, connects the KMN to the chromosome-proximal domain of the kinetochore through a direct interaction with CENP-C. The structural basis for this crucial bridging function of MIS12C is unknown. Here, we report crystal structures of human MIS12C associated with a fragment of CENP-C and unveil the role of Aurora B kinase in the regulation of this interaction. The structure of MIS12:CENP-C complements previously determined high-resolution structures of functional regions of NDC80C and KNL1C and allows us to build a near-complete structural model of the KMN assembly. Our work illuminates the structural organization of essential chromosome segregation machinery that is conserved in most eukaryotes. We report a crystal structure of human MIS12 complex, a crucial kinetochore component The structure reveals how the MIS12 complex binds its kinetochore receptor CENP-C We dissect how Aurora B kinase promotes the MIS12:CENP-C interaction A combination of diverse structural methods reveals outer kinetochore organization
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Affiliation(s)
- Arsen Petrovic
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Jenny Keller
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Yahui Liu
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Katharina Overlack
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Juliane John
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Yoana N Dimitrova
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115
| | - Simon Jenni
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115
| | - Suzan van Gerwen
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Patricia Stege
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Sabine Wohlgemuth
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Pascaline Rombaut
- Gene Center Munich, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Franz Herzog
- Gene Center Munich, Ludwig-Maximilians-Universität München, Feodor-Lynen-Str. 25, 81377 Munich, Germany
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115; Department of Biological Chemistry and Molecular Pharmacology, Howard Hughes Medical Institute, Harvard Medical School, 250 Longwood Avenue, Boston, MA 02115
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Faculty of Biology, Centre for Medical Biotechnology, University Duisburg-Essen, Universitätsstrasse, 45141 Essen, Germany.
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37
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Drosophila Nnf1 paralogs are partially redundant for somatic and germ line kinetochore function. Chromosoma 2016; 126:145-163. [DOI: 10.1007/s00412-016-0579-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 02/03/2016] [Accepted: 02/08/2016] [Indexed: 10/22/2022]
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38
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Herrero E, Thorpe PH. Synergistic Control of Kinetochore Protein Levels by Psh1 and Ubr2. PLoS Genet 2016; 12:e1005855. [PMID: 26891228 PMCID: PMC4758618 DOI: 10.1371/journal.pgen.1005855] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Accepted: 01/19/2016] [Indexed: 12/02/2022] Open
Abstract
The accurate segregation of chromosomes during cell division is achieved by attachment of chromosomes to the mitotic spindle via the kinetochore, a large multi-protein complex that assembles on centromeres. The budding yeast kinetochore comprises more than 60 different proteins. Although the structure and function of many of these proteins has been investigated, we have little understanding of the steady state regulation of kinetochores. The primary model of kinetochore homeostasis suggests that kinetochores assemble hierarchically from the centromeric DNA via the inclusion of a centromere-specific histone into chromatin. We tested this model by trying to perturb kinetochore protein levels by overexpressing an outer kinetochore gene, MTW1. This increase in protein failed to change protein recruitment, consistent with the hierarchical assembly model. However, we find that deletion of Psh1, a key ubiquitin ligase that is known to restrict inner kinetochore protein loading, does not increase levels of outer kinetochore proteins, thus breaking the normal kinetochore stoichiometry. This perturbation leads to chromosome segregation defects, which can be partially suppressed by mutation of Ubr2, a second ubiquitin ligase that normally restricts protein levels at the outer kinetochore. Together these data show that Psh1 and Ubr2 synergistically control the amount of proteins at the kinetochore.
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Affiliation(s)
- Eva Herrero
- The Francis Crick Institute, Mill Hill Laboratory, London, United Kingdom
| | - Peter H. Thorpe
- The Francis Crick Institute, Mill Hill Laboratory, London, United Kingdom
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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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40
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Krefman NI, Drubin DG, Barnes G. Control of the spindle checkpoint by lateral kinetochore attachment and limited Mad1 recruitment. Mol Biol Cell 2015; 26:2620-39. [PMID: 26023090 PMCID: PMC4501360 DOI: 10.1091/mbc.e15-05-0276] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 05/18/2015] [Indexed: 01/06/2023] Open
Abstract
The spindle checkpoint proteins Mad1 and Bub1 are dynamically recruited after induced de novo kinetochore assembly. Detached kinetochores compete with alternate binding sites in the nucleus to recruit Mad1 and Bub1 from very limited pools. Lateral kinetochore attachment to microtubules licenses Mad1 removal from kinetochores. We observed the dynamic recruitment of spindle checkpoint proteins Mad1 and Bub1 to detached kinetochores in budding yeast using real-time live-cell imaging and quantified recruitment in fixed cells. After induced de novo kinetochore assembly at one pair of sister centromeres, Mad1 appeared after the kinetochore protein Mtw1. Detached kinetochores were not associated with the nuclear envelope, so Mad1 does not anchor them to nuclear pore complexes (NPCs). Disrupting Mad1's NPC localization increased Mad1 recruitment to detached sister kinetochores. Conversely, increasing the number of detached kinetochores reduced the amount of Mad1 per detached kinetochore. Bub1 also relocalized completely from the spindle to detached sister centromeres after kinetochore assembly. After their capture by microtubules, Mad1 and Bub1 progressively disappeared from kinetochores. Sister chromatids that arrested with a lateral attachment to one microtubule exhibited half the Mad1 of fully detached sisters. We propose that detached kinetochores compete with alternate binding sites in the nucleus to recruit Mad1 and Bub1 from available pools that are small enough to be fully depleted by just one pair of detached kinetochores and that lateral attachment licenses Mad1 removal from kinetochores after a kinetic delay.
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Affiliation(s)
- Nathaniel I Krefman
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720
| | - David G Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720
| | - Georjana Barnes
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720
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Abendroth C, Hofmeister A, Hake SB, Kamweru PK, Miess E, Dornblut C, Küffner I, Deng W, Leonhardt H, Orthaus S, Hoischen C, Diekmann S. The CENP-T C-terminus is exclusively proximal to H3.1 and not to H3.2 or H3.3. Int J Mol Sci 2015; 16:5839-63. [PMID: 25775162 PMCID: PMC4394509 DOI: 10.3390/ijms16035839] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 02/18/2015] [Accepted: 02/18/2015] [Indexed: 12/17/2022] Open
Abstract
The kinetochore proteins assemble onto centromeric chromatin and regulate DNA segregation during cell division. The inner kinetochore proteins bind centromeres while most outer kinetochore proteins assemble at centromeres during mitosis, connecting the complex to microtubules. The centromere-kinetochore complex contains specific nucleosomes and nucleosomal particles. CENP-A replaces canonical H3 in centromeric nucleosomes, defining centromeric chromatin. Next to CENP-A, the CCAN multi-protein complex settles which contains CENP-T/W/S/X. These four proteins are described to form a nucleosomal particle at centromeres. We had found the CENP-T C-terminus and the CENP-S termini next to histone H3.1 but not to CENP-A, suggesting that the Constitutive Centromere-Associated Network (CCAN) bridges a CENP-A- and a H3-containing nucleosome. Here, we show by in vivo FRET that this proximity between CENP-T and H3 is specific for H3.1 but neither for the H3.1 mutants H3.1(C96A) and H3.1(C110A) nor for H3.2 or H3.3. We also found CENP-M next to H3.1 but not to these H3.1 mutants. Consistently, we detected CENP-M next to CENP-S. These data elucidate the local molecular neighborhood of CCAN proteins next to a H3.1-containing centromeric nucleosome. They also indicate an exclusive position of H3.1 clearly distinct from H3.2, thus documenting a local, and potentially also functional, difference between H3.1 and H3.2.
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Affiliation(s)
- Christian Abendroth
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Antje Hofmeister
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Sandra B Hake
- Department of Molecular Biology, Center for Integrated Protein Science Munich (CIPSM), Adolf-Butenandt-Institute, Ludwig-Maximilians-Universität Munich, Schillerstr. 44, D-80336 Munich, Germany.
| | - Paul K Kamweru
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Elke Miess
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Carsten Dornblut
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Isabell Küffner
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Wen Deng
- Department of Biology II, Center for Integrated Protein Science, Ludwig-Maximilians-Universität Munich, Planegg-Martinsried, D-82152 Munich, Germany.
| | - Heinrich Leonhardt
- Department of Biology II, Center for Integrated Protein Science, Ludwig-Maximilians-Universität Munich, Planegg-Martinsried, D-82152 Munich, Germany.
| | | | - Christian Hoischen
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
| | - Stephan Diekmann
- Molecular Biology, Fritz Lipmann Institute, Beutenbergstr. 11, D-07745 Jena, Germany.
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The Mps1 kinase modulates the recruitment and activity of Cnn1(CENP-T) at Saccharomyces cerevisiae kinetochores. Genetics 2015; 200:79-90. [PMID: 25716979 DOI: 10.1534/genetics.115.175786] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 02/24/2015] [Indexed: 02/04/2023] Open
Abstract
Kinetochores are conserved protein complexes that bind the replicated chromosomes to the mitotic spindle and then direct their segregation. To better comprehend Saccharomyces cerevisiae kinetochore function, we dissected the phospho-regulated dynamic interaction between conserved kinetochore protein Cnn1(CENP-T), the centromere region, and the Ndc80 complex through the cell cycle. Cnn1 localizes to kinetochores at basal levels from G1 through metaphase but accumulates abruptly at anaphase onset. How Cnn1 is recruited and which activities regulate its dynamic localization are unclear. We show that Cnn1 harbors two kinetochore-localization activities: a C-terminal histone-fold domain (HFD) that associates with the centromere region and a N-terminal Spc24/Spc25 interaction sequence that mediates linkage to the microtubule-binding Ndc80 complex. We demonstrate that the established Ndc80 binding site in the N terminus of Cnn1, Cnn1(60-84), should be extended with flanking residues, Cnn1(25-91), to allow near maximal binding affinity to Ndc80. Cnn1 localization was proposed to depend on Mps1 kinase activity at Cnn1-S74, based on in vitro experiments demonstrating the Cnn1-Ndc80 complex interaction. We demonstrate that from G1 through metaphase, Cnn1 localizes via both its HFD and N-terminal Spc24/Spc25 interaction sequence, and deletion or mutation of either region results in anomalous Cnn1 kinetochore levels. At anaphase onset (when Mps1 activity decreases) Cnn1 becomes enriched mainly via the N-terminal Spc24/Spc25 interaction sequence. In sum, we provide the first in vivo evidence of Cnn1 preanaphase linkages with the kinetochore and enrichment of the linkages during anaphase.
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Hornung P, Troc P, Malvezzi F, Maier M, Demianova Z, Zimniak T, Litos G, Lampert F, Schleiffer A, Brunner M, Mechtler K, Herzog F, Marlovits TC, Westermann S. A cooperative mechanism drives budding yeast kinetochore assembly downstream of CENP-A. ACTA ACUST UNITED AC 2014; 206:509-24. [PMID: 25135934 PMCID: PMC4137059 DOI: 10.1083/jcb.201403081] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During kinetochore assembly in budding yeast, the key steps of CENP-A recognition and outer kinetochore recruitment are executed through different yeast CCAN subunits, potentially protecting against inappropriate kinetochore assembly. Kinetochores are megadalton-sized protein complexes that mediate chromosome–microtubule interactions in eukaryotes. How kinetochore assembly is triggered specifically on centromeric chromatin is poorly understood. Here we use biochemical reconstitution experiments alongside genetic and structural analysis to delineate the contributions of centromere-associated proteins to kinetochore assembly in yeast. We show that the conserved kinetochore subunits Ame1CENP-U and Okp1CENP-Q form a DNA-binding complex that associates with the microtubule-binding KMN network via a short Mtw1 recruitment motif in the N terminus of Ame1. Point mutations in the Ame1 motif disrupt kinetochore function by preventing KMN assembly on chromatin. Ame1–Okp1 directly associates with the centromere protein C (CENP-C) homologue Mif2 to form a cooperative binding platform for outer kinetochore assembly. Our results indicate that the key assembly steps, CENP-A recognition and outer kinetochore recruitment, are executed through different yeast constitutive centromere-associated network subunits. This two-step mechanism may protect against inappropriate kinetochore assembly similar to rate-limiting nucleation steps used by cytoskeletal polymers.
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Affiliation(s)
- Peter Hornung
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Paulina Troc
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Francesca Malvezzi
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Michael Maier
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Zuzana Demianova
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Tomasz Zimniak
- Department of Biochemistry, Gene Center, Ludwig-Maximilians Universität München, 81377 Munich, Germany
| | - Gabriele Litos
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Fabienne Lampert
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Alexander Schleiffer
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria Institute of Molecular Biotechnology GmbH, Austrian Academy of Sciences, 1030 Vienna, Austria
| | - Matthias Brunner
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria Institute of Molecular Biotechnology GmbH, Austrian Academy of Sciences, 1030 Vienna, Austria Center for Structural Systems Biology, University Medical Center Eppendorf-Hamburg, 20246 Hamburg, Germany Deutsches Elektronen-Synchrotron, 22607 Hamburg, Germany
| | - Karl Mechtler
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
| | - Franz Herzog
- Department of Biochemistry, Gene Center, Ludwig-Maximilians Universität München, 81377 Munich, Germany
| | - Thomas C Marlovits
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria Institute of Molecular Biotechnology GmbH, Austrian Academy of Sciences, 1030 Vienna, Austria Center for Structural Systems Biology, University Medical Center Eppendorf-Hamburg, 20246 Hamburg, Germany Deutsches Elektronen-Synchrotron, 22607 Hamburg, Germany
| | - Stefan Westermann
- Research Institute of Molecular Pathology, Vienna Biocenter, 1030 Vienna, Austria
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Basilico F, Maffini S, Weir JR, Prumbaum D, Rojas AM, Zimniak T, De Antoni A, Jeganathan S, Voss B, van Gerwen S, Krenn V, Massimiliano L, Valencia A, Vetter IR, Herzog F, Raunser S, Pasqualato S, Musacchio A. The pseudo GTPase CENP-M drives human kinetochore assembly. eLife 2014; 3:e02978. [PMID: 25006165 PMCID: PMC4080450 DOI: 10.7554/elife.02978] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Kinetochores, multi-subunit complexes that assemble at the interface with centromeres, bind spindle microtubules to ensure faithful delivery of chromosomes during cell division. The configuration and function of the kinetochore-centromere interface is poorly understood. We report that a protein at this interface, CENP-M, is structurally and evolutionarily related to small GTPases but is incapable of GTP-binding and conformational switching. We show that CENP-M is crucially required for the assembly and stability of a tetramer also comprising CENP-I, CENP-H, and CENP-K, the HIKM complex, which we extensively characterize through a combination of structural, biochemical, and cell biological approaches. A point mutant affecting the CENP-M/CENP-I interaction hampers kinetochore assembly and chromosome alignment and prevents kinetochore recruitment of the CENP-T/W complex, questioning a role of CENP-T/W as founder of an independent axis of kinetochore assembly. Our studies identify a single pathway having CENP-C as founder, and CENP-H/I/K/M and CENP-T/W as CENP-C-dependent followers.DOI: http://dx.doi.org/10.7554/eLife.02978.001.
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Affiliation(s)
- Federica Basilico
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Stefano Maffini
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - John R Weir
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Daniel Prumbaum
- Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Ana M Rojas
- Computational Biology and Bioinformatics Group, Institute of Biomedicine of Seville, Campus Hospital Universitario Virgen del Rocio, Seville, Spain
| | - Tomasz Zimniak
- Department of Biochemistry and Gene Center, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - Anna De Antoni
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Sadasivam Jeganathan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Beate Voss
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Suzan van Gerwen
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Veronica Krenn
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Lucia Massimiliano
- Department of Experimental Oncology, European Institute of Oncology, Milan, Italy
| | - Alfonso Valencia
- Structural Biology and Biocomputing Programme, Spanish National Cancer Centre-CNIO, Madrid, Spain
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Franz Herzog
- Department of Biochemistry and Gene Center, Ludwig-Maximilians-Universität, München, Munich, Germany
| | - Stefan Raunser
- Department of Physical Biochemistry, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany Centre for Medical Biotechnology, Faculty of Biology, University of Duisburg-Essen, Essen, Germany
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45
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Aravamudhan P, Felzer-Kim I, Gurunathan K, Joglekar AP. Assembling the protein architecture of the budding yeast kinetochore-microtubule attachment using FRET. Curr Biol 2014; 24:1437-46. [PMID: 24930965 PMCID: PMC4320969 DOI: 10.1016/j.cub.2014.05.014] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/20/2014] [Accepted: 05/06/2014] [Indexed: 11/20/2022]
Abstract
BACKGROUND The kinetochore is a multiprotein machine that couples chromosome movement to microtubule (MT) polymerization and depolymerization. It uses numerous copies of at least three MT-binding proteins to generate bidirectional movement. The nanoscale organization of these proteins within the kinetochore plays an important role in shaping the mechanisms that drive persistent, bidirectional movement of the kinetochore. RESULTS We used fluorescence resonance energy transfer (FRET) between genetically encoded fluorescent proteins fused to kinetochore subunits to reconstruct the nanoscale organization of the budding yeast kinetochore. We performed >60 FRET and high-resolution colocalization measurements involving the essential MT-binding kinetochore components: Ndc80, Dam1, Spc105, and Stu2. These measurements reveal that neighboring Ndc80 complexes within the kinetochore are narrowly distributed along the length of the MT. Dam1 complex molecules are concentrated near the MT-binding domains of Ndc80. Stu2 localizes in high abundance within a narrowly defined territory within the kinetochore centered ∼20 nm on the centromeric side of the Dam1 complex. CONCLUSIONS Our data show that the MT attachment site of the budding yeast kinetochore is well organized. Ndc80, Dam1, and Stu2 are all narrowly distributed about their average positions along the kinetochore-MT axis. The relative organization of these components, their narrow distributions, and their known MT-binding properties together elucidate how their combined actions generate persistent, bidirectional kinetochore movement coupled to MT polymerization and depolymerization.
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Affiliation(s)
- Pavithra Aravamudhan
- Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, MI 48109-1055, USA
| | - Isabella Felzer-Kim
- Cell and Developmental Biology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA
| | - Kaushik Gurunathan
- Sastra University, Tirumalaisamudram, Thanjavur, Tamil Nadu 613402, India
| | - Ajit P Joglekar
- Biophysics, University of Michigan, 930 North University Avenue, Ann Arbor, MI 48109-1055, USA; Cell and Developmental Biology, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA.
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46
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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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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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48
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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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49
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Mon H, Lee JM, Mita K, Goldsmith MR, Kusakabe T. Chromatin-induced spindle assembly plays an important role in metaphase congression of silkworm holocentric chromosomes. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2014; 45:40-50. [PMID: 24291286 DOI: 10.1016/j.ibmb.2013.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/19/2013] [Accepted: 11/21/2013] [Indexed: 06/02/2023]
Abstract
The kinetochore plays important roles in cell cycle progression. Interactions between chromosomes and spindle microtubules allow chromosomes to congress to the middle of the cell and to segregate the sister chromatids into daughter cells in mitosis. The chromosome passenger complex (CPC), composed of the Aurora B kinase and its regulatory subunits INCENP, Survivin, and Borealin, plays multiple roles in these chromosomal events. In the genome of the silkworm, Bombyx mori, which has holocentric chromosomes, the CPC components and their molecular interactions were highly conserved. In contrast to monocentric species, however, the silkworm CPC co-localized with the chromatin-driven spindles on the upper side of prometaphase chromosomes without forming bipolar mitotic spindles. Depletion of the CPC by RNAi arrested the cell cycle progression at prometaphase and disrupted the microtubule network of the chromatin-driven spindles. Interestingly, depletion of mitotic centromere-associated kinesin (MCAK) recovered formation of the microtubule network but did not overcome the cell cycle arrest at prometaphase. These results suggest that the CPC modulates the chromatin-induced spindle assembly and metaphase congression of silkworm holocentric chromosomes.
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Affiliation(s)
- Hiroaki Mon
- Laboratory of Silkworm Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan
| | - Jae Man Lee
- Laboratory of Silkworm Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan
| | - Kazuei Mita
- Laboratory of Molecular Genetics, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500001, India
| | - Marian R Goldsmith
- Biological Sciences Department, University of Rhode Island, Kingston, RI 02881, USA
| | - Takahiro Kusakabe
- Laboratory of Silkworm Science, Kyushu University Graduate School of Bioresource and Bioenvironmental Sciences, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan.
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50
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Nilsson J. Looping in on Ndc80 - how does a protein loop at the kinetochore control chromosome segregation? Bioessays 2014; 34:1070-7. [PMID: 23154893 DOI: 10.1002/bies.201200096] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Segregation of chromosomes during mitosis requires the interaction of dynamic microtubules with the kinetochore, a large protein structure established on the centromere region of sister chromatids. The core microtubule-binding activity of the kinetochore resides in the KMN network, an outer kinetochore complex. As part of the KMN network, the Ndc80 complex, which is composed of Ndc80, Nuf2, Spc24, and Spc25, is able to bind directly to microtubules and has the ability to track with depolymerizing microtubules to produce chromosome movement. The Ndc80 complex binds directly to microtubules through a calponin homology domain and an unstructured tail in the N terminus of the Ndc80 protein. A recent flurry of papers has highlighted the importance of an internal loop region in Ndc80 in establishing end-on attachment to microtubules. Here I discuss these recent findings that suggest that the Ndc80 internal loop functions as a binding site for proteins required for kinetochore-microtubule interactions.
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Affiliation(s)
- Jakob Nilsson
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health Science, University of Copenhagen, Copenhagen, Denmark.
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