1
|
Barrero DJ, Wijeratne SS, Zhao X, Cunningham GF, Yan R, Nelson CR, Arimura Y, Funabiki H, Asbury CL, Yu Z, Subramanian R, Biggins S. Architecture of native kinetochores revealed by structural studies utilizing a thermophilic yeast. Curr Biol 2024; 34:3881-3893.e5. [PMID: 39127048 PMCID: PMC11387133 DOI: 10.1016/j.cub.2024.07.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 05/30/2024] [Accepted: 07/08/2024] [Indexed: 08/12/2024]
Abstract
Eukaryotic chromosome segregation requires kinetochores, multi-megadalton protein machines that assemble on the centromeres of chromosomes and mediate attachments to dynamic spindle microtubules. Kinetochores are built from numerous complexes, and there has been progress in structural studies on recombinant subassemblies. However, there is limited structural information on native kinetochore architecture. To address this, we purified functional, native kinetochores from the thermophilic yeast Kluyveromyces marxianus and examined them by electron microscopy (EM), cryoelectron tomography (cryo-ET), and atomic force microscopy (AFM). The kinetochores are extremely large, flexible assemblies that exhibit features consistent with prior models. We assigned kinetochore polarity by visualizing their interactions with microtubules and locating the microtubule binder, Ndc80c. This work shows that isolated kinetochores are more dynamic and complex than what might be anticipated based on the known structures of recombinant subassemblies and provides the foundation to study the global architecture and functions of kinetochores at a structural level.
Collapse
Affiliation(s)
- Daniel J Barrero
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA; Molecular and Cellular Biology Program, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Sithara S Wijeratne
- Department of Molecular Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Xiaowei Zhao
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Grace F Cunningham
- Department of Molecular Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Rui Yan
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Christian R Nelson
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA
| | - Yasuhiro Arimura
- The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | | | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Zhiheng Yu
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA.
| |
Collapse
|
2
|
GİRGİN SM, ÇAYDAŞI AKOCA. Bud14 function is crucial for spindle pole body size maintenance. Turk J Biol 2024; 48:267-278. [PMID: 39296336 PMCID: PMC11407341 DOI: 10.55730/1300-0152.2702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 08/23/2024] [Accepted: 08/05/2024] [Indexed: 09/21/2024] Open
Abstract
Background/aim Spindle pole bodies (SPB), the functional equivalent of centrosomes in yeast, duplicate through generation of a new SPB next to the old one. However, SPBs are dynamic structures that can grow and exchange, and mechanisms that regulate SPB size remain largely unknown. This study aims to elucidate the role of Bud14 in SPB size maintenance in Saccharomyces cerevisiae. Materials and methods We employed quantitative fluorescence microscopy to assess the relative and absolute amounts of SPB structural proteins at SPBs of wildtype cells and in cells lacking BUD14 (bud14Δ). Quantifications were performed using asynchronous cell cultures, as well as cultures synchronously progressing through the cell cycle and upon different cell cycle arrests. We also utilized mutants that allow the separation of Bud14 functions. Results Our results indicate that higher levels of SPB inner, outer, and central plaque proteins are present at the SPBs of bud14Δ cells compared to wildtype cells during anaphase, as well as during nocodazole-induced M-phase arrest. However, during α-factor mediated G1 arrest, inner and outer plaque proteins responded differently to the absence of BUD14. A Bud14 mutant that cannot interact with the Protein Phosphatase 1 (Glc7) phenocopied bud14Δ in terms of SPB-bound levels of the inner plaque protein Spc110, whereas disruption of Bud14-Kel1-Kel2 complex did not alter Spc110 levels at SPBs. In cells synchronously released from α-factor arrest, lack of Bud14-Glc7 caused increase of Spc110 at the SPBs at early stages of the cell cycle. Conclusion We identified Bud14 as a critical protein for SPB size maintenance. The interaction of Bud14 with Glc7, but not with the Kelch proteins, is indispensable for restricting levels of Spc110 incorporated into the SPBs.
Collapse
Affiliation(s)
- Sevilay Münire GİRGİN
- Department of Molecular Biology and Genetics, Collage of Sciences, Koç University, İstanbul,
Turkiye
| | - Ayşe KOCA ÇAYDAŞI
- Department of Molecular Biology and Genetics, Collage of Sciences, Koç University, İstanbul,
Turkiye
| |
Collapse
|
3
|
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.
Collapse
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
| |
Collapse
|
4
|
Zhao P, Xu L, Li B, Zhao Y, Zhao Y, Lu Y, Cao M, Li G, Weng TC, Wang H, Zheng Y. Non-Equilibrium Assembly of Atomically-Precise Copper Nanoclusters. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2311818. [PMID: 38294175 DOI: 10.1002/adma.202311818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/12/2024] [Indexed: 02/01/2024]
Abstract
Accurate structure control in dissipative assemblies (DSAs) is vital for precise biological functions. However, accuracy and functionality of artificial DSAs are far from this objective. Herein, a novel approach is introduced by harnessing complex chemical reaction networks rooted in coordination chemistry to create atomically-precise copper nanoclusters (CuNCs), specifically Cu11(µ9-Cl)(µ3-Cl)3L6Cl (L = 4-methyl-piperazine-1-carbodithioate). Cu(I)-ligand ratio change and dynamic Cu(I)-Cu(I) metallophilic/coordination interactions enable the reorganization of CuNCs into metastable CuL2, finally converting into equilibrium [CuL·Y]Cl (Y = MeCN/H2O) via Cu(I) oxidation/reorganization and ligand exchange process. Upon adding ascorbic acid (AA), the system goes further dissipative cycles. It is observed that the encapsulated/bridging halide ions exert subtle influence on the optical properties of CuNCs and topological changes of polymeric networks when integrating CuNCs as crosslink sites. CuNCs duration/switch period could be controlled by varying the ions, AA concentration, O2 pressure and pH. Cu(I)-Cu(I) metallophilic and coordination interactions provide a versatile toolbox for designing delicate life-like materials, paving the way for DSAs with precise structures and functionalities. Furthermore, CuNCs can be employed as modular units within polymers for materials mechanics or functionalization studies.
Collapse
Affiliation(s)
- Peng Zhao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Linjie Xu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Bohan Li
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Yuanfeng Zhao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Yingshuai Zhao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Yan Lu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Minghui Cao
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Guoqi Li
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Tsu-Chien Weng
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
- State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, China
| | - Heng Wang
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, 518060, China
| | - Yijun Zheng
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| |
Collapse
|
5
|
Zahm JA, Harrison SC. A communication hub for phosphoregulation of kinetochore-microtubule attachment. Curr Biol 2024; 34:2308-2318.e6. [PMID: 38776904 DOI: 10.1016/j.cub.2024.04.067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 04/06/2024] [Accepted: 04/29/2024] [Indexed: 05/25/2024]
Abstract
The Mps1 and Aurora B kinases regulate and monitor kinetochore attachment to spindle microtubules during cell division, ultimately ensuring accurate chromosome segregation. In yeast, the critical spindle attachment components are the Ndc80 and Dam1 complexes (Ndc80c and DASH/Dam1c, respectively). Ndc80c is a 600-Å-long heterotetramer that binds microtubules through a globular "head" at one end and centromere-proximal kinetochore components through a globular knob at the other end. Dam1c is a heterodecamer that forms a ring of 16-17 protomers around the shaft of the single kinetochore microtubule in point-centromere yeast. The ring coordinates the approximately eight Ndc80c rods per kinetochore. In published work, we showed that a site on the globular "head" of Ndc80c, including residues from both Ndc80 and Nuf2, binds a bipartite segment in the long C-terminal extension of Dam1. Results reported here show, both by in vitro binding experiments and by crystal structure determination, that the same site binds a conserved segment in the long N-terminal extension of Mps1. It also binds, less tightly, a conserved segment in the N-terminal extension of Ipl1 (yeast Aurora B). Together with results from experiments in yeast cells and from biochemical assays reported in two accompanying papers, the structures and graded affinities identify a communication hub for ensuring uniform bipolar attachment and for signaling anaphase onset.
Collapse
Affiliation(s)
- Jacob A Zahm
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA
| | - Stephen C Harrison
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Boston, MA 02115, USA.
| |
Collapse
|
6
|
Pleuger R, Cozma C, Hohoff S, Denkhaus C, Dudziak A, Kaschani F, Kaiser M, Musacchio A, Vetter IR, Westermann S. Microtubule end-on attachment maturation regulates Mps1 association with its kinetochore receptor. Curr Biol 2024; 34:2279-2293.e6. [PMID: 38776902 DOI: 10.1016/j.cub.2024.03.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 02/23/2024] [Accepted: 03/27/2024] [Indexed: 05/25/2024]
Abstract
Faithful chromosome segregation requires that sister chromatids establish bi-oriented kinetochore-microtubule attachments. The spindle assembly checkpoint (SAC) prevents premature anaphase onset with incomplete attachments. However, how microtubule attachment and checkpoint signaling are coordinated remains unclear. The conserved kinase Mps1 initiates SAC signaling by localizing transiently to kinetochores in prometaphase and is released upon bi-orientation. Using biochemistry, structure predictions, and cellular assays, we shed light on this dynamic behavior in Saccharomyces cerevisiae. A conserved N-terminal segment of Mps1 binds the neck region of Ndc80:Nuf2, the main microtubule receptor of kinetochores. Mutational disruption of this interface, located at the backside of the paired CH domains and opposite the microtubule-binding site, prevents Mps1 localization, eliminates SAC signaling, and impairs growth. The same interface of Ndc80:Nuf2 binds the microtubule-associated Dam1 complex. We demonstrate that the error correction kinase Ipl1/Aurora B controls the competition between Dam1 and Mps1 for the same binding site. Thus, binding of the Dam1 complex to Ndc80:Nuf2 may release Mps1 from the kinetochore to promote anaphase onset.
Collapse
Affiliation(s)
- Richard Pleuger
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Christian Cozma
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Simone Hohoff
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Christian Denkhaus
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Alexander Dudziak
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Farnusch Kaschani
- Department of Chemical Biology and ACE Analytical Core Facility Essen, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Markus Kaiser
- Department of Chemical Biology and ACE Analytical Core Facility Essen, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Stefan Westermann
- Department of Molecular Genetics, Faculty of Biology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany; Center of Medical Biotechnology, University of Duisburg-Essen, Universitätsstrasse 5, 45117 Essen, Germany.
| |
Collapse
|
7
|
Cook D, Kozmin SG, Yeh E, Petes TD, Bloom K. Dicentric chromosomes are resolved through breakage and repair at their centromeres. Chromosoma 2024; 133:117-134. [PMID: 38165460 PMCID: PMC11180013 DOI: 10.1007/s00412-023-00814-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 11/11/2023] [Accepted: 12/21/2023] [Indexed: 01/03/2024]
Abstract
Chromosomes with two centromeres provide a unique opportunity to study chromosome breakage and DNA repair using completely endogenous cellular machinery. Using a conditional transcriptional promoter to control the second centromere, we are able to activate the dicentric chromosome and follow the appearance of DNA repair products. We find that the rate of appearance of DNA repair products resulting from homology-based mechanisms exceeds the expected rate based on their limited centromere homology (340 bp) and distance from one another (up to 46.3 kb). In order to identify whether DNA breaks originate in the centromere, we introduced 12 single-nucleotide polymorphisms (SNPs) into one of the centromeres. Analysis of the distribution of SNPs in the recombinant centromeres reveals that recombination was initiated with about equal frequency within the conserved centromere DNA elements CDEII and CDEIII of the two centromeres. The conversion tracts range from about 50 bp to the full length of the homology between the two centromeres (340 bp). Breakage and repair events within and between the centromeres can account for the efficiency and distribution of DNA repair products. We propose that in addition to providing a site for kinetochore assembly, the centromere may be a point of stress relief in the face of genomic perturbations.
Collapse
Affiliation(s)
- Diana Cook
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, NC, 27599-3280, USA
| | - Stanislav G Kozmin
- Department of Molecular Genetics & Microbiology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Elaine Yeh
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, NC, 27599-3280, USA
| | - Thomas D Petes
- Department of Molecular Genetics & Microbiology, Duke University School of Medicine, Durham, NC, 27710, USA
| | - Kerry Bloom
- Department of Biology, University of North Carolina Chapel Hill, Chapel Hill, NC, 27599-3280, USA.
| |
Collapse
|
8
|
Barrero DJ, Wijeratne SS, Zhao X, Cunningham GF, Rui Y, Nelson CR, Yasuhiro A, Funabiki H, Asbury CL, Yu Z, Subramanian R, Biggins S. Architecture and flexibility of native kinetochores revealed by structural studies utilizing a thermophilic yeast. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.28.582571. [PMID: 38464254 PMCID: PMC10925344 DOI: 10.1101/2024.02.28.582571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Eukaryotic chromosome segregation requires kinetochores, multi-megadalton protein machines that assemble on the centromeres of chromosomes and mediate attachments to dynamic spindle microtubules. Kinetochores are built from numerous complexes, and understanding how they are arranged is key to understanding how kinetochores perform their multiple functions. However, an integrated understanding of kinetochore architecture has not yet been established. To address this, we purified functional, native kinetochores from Kluyveromyces marxianus and examined them by electron microscopy, cryo-electron tomography and atomic force microscopy. The kinetochores are extremely large, flexible assemblies that exhibit features consistent with prior models. We assigned kinetochore polarity by visualizing their interactions with microtubules and locating the microtubule binder Ndc80c. This work shows that isolated kinetochores are more dynamic and complex than what might be anticipated based on the known structures of recombinant subassemblies, and provides the foundation to study the global architecture and functions of kinetochores at a structural level.
Collapse
Affiliation(s)
- Daniel J. Barrero
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA
- Molecular and Cellular Biology Program, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Sithara S. Wijeratne
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Xiaowei Zhao
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Grace F. Cunningham
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Yan Rui
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Christian R. Nelson
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA
| | - Arimura Yasuhiro
- The Rockefeller University, 1230 York Ave., New York, NY 10065, USA
| | | | - Charles L. Asbury
- Department of Physiology and Biophysics, 1959 NE Pacific Street, University of Washington, Seattle, WA 98195, USA
| | - Zhiheng Yu
- Howard Hughes Medical Institute Janelia Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Radhika Subramanian
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Ave. N., Seattle, WA 98109, USA
| |
Collapse
|
9
|
Sankaranarayanan SR, Polisetty SD, Das K, Dumbrepatil A, Medina-Pritchard B, Singleton M, Jeyaprakash AA, Sanyal K. Functional plasticity in chromosome-microtubule coupling on the evolutionary time scale. Life Sci Alliance 2023; 6:e202201720. [PMID: 37793775 PMCID: PMC10551642 DOI: 10.26508/lsa.202201720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 09/15/2023] [Accepted: 09/19/2023] [Indexed: 10/06/2023] Open
Abstract
The Dam1 complex is essential for mitotic progression across evolutionarily divergent fungi. Upon analyzing amino acid (aa) sequences of Dad2, a Dam1 complex subunit, we identified a conserved 10-aa-long Dad2 signature sequence (DSS). An arginine residue (R126) in the DSS is essential for viability in Saccharomyces cerevisiae that possesses point centromeres. The corresponding arginine residues are functionally important but not essential for viability in Candida albicans and Cryptococcus neoformans; both carry several kilobases long regional centromeres. The purified recombinant Dam1 complex containing either Dad2ΔDSS or Dad2R126A failed to bind microtubules (MTs) or form any visible rings like the WT complex. Intriguingly, functional analysis revealed that the requirement of the conserved arginine residue for chromosome biorientation and mitotic progression reduced with increasing centromere length. We propose that plasticity of the invariant arginine of Dad2 in organisms with regional centromeres is achieved by conditional elevation of the kinetochore protein(s) to enable multiple kinetochore MTs to bind to each chromosome. The capacity of a chromosome to bind multiple kinetochore MTs may mask the deleterious effects of such lethal mutations.
Collapse
Affiliation(s)
- Sundar Ram Sankaranarayanan
- https://ror.org/0538gdx71 Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Satya Dev Polisetty
- https://ror.org/0538gdx71 Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Kuladeep Das
- https://ror.org/0538gdx71 Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Arti Dumbrepatil
- https://ror.org/0538gdx71 Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| | - Bethan Medina-Pritchard
- https://ror.org/01nrxwf90 Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Martin Singleton
- https://ror.org/01nrxwf90 Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - A Arockia Jeyaprakash
- https://ror.org/01nrxwf90 Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
- Gene Center and Department of Biochemistry, Ludwig-Maximilian-Universität, Munich, Germany
| | - Kaustuv Sanyal
- https://ror.org/0538gdx71 Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru, India
| |
Collapse
|
10
|
Popchock AR, Larson JD, Dubrulle J, Asbury CL, Biggins S. Direct observation of coordinated assembly of individual native centromeric nucleosomes. EMBO J 2023; 42:e114534. [PMID: 37469281 PMCID: PMC10476280 DOI: 10.15252/embj.2023114534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/27/2023] [Accepted: 07/04/2023] [Indexed: 07/21/2023] Open
Abstract
Eukaryotic chromosome segregation requires the kinetochore, a megadalton-sized machine that forms on specialized centromeric chromatin containing CENP-A, a histone H3 variant. CENP-A deposition requires a chaperone protein HJURP that targets it to the centromere, but it has remained unclear whether HJURP has additional functions beyond CENP-A targeting and why high AT DNA content, which disfavors nucleosome assembly, is widely conserved at centromeres. To overcome the difficulties of studying nucleosome formation in vivo, we developed a microscopy assay that enables direct observation of de novo centromeric nucleosome recruitment and maintenance with single molecule resolution. Using this assay, we discover that CENP-A can arrive at centromeres without its dedicated centromere-specific chaperone HJURP, but stable incorporation depends on HJURP and additional DNA-binding proteins of the inner kinetochore. We also show that homopolymer AT runs in the yeast centromeres are essential for efficient CENP-A deposition. Together, our findings reveal requirements for stable nucleosome formation and provide a foundation for further studies of the assembly and dynamics of native kinetochore complexes.
Collapse
Affiliation(s)
- Andrew R Popchock
- Basic Sciences Division, Howard Hughes Medical InstituteFred Hutchinson Cancer CenterSeattleWAUSA
| | - Joshua D Larson
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | | | - Charles L Asbury
- Department of Physiology and BiophysicsUniversity of WashingtonSeattleWAUSA
| | - Sue Biggins
- Basic Sciences Division, Howard Hughes Medical InstituteFred Hutchinson Cancer CenterSeattleWAUSA
| |
Collapse
|
11
|
Dendooven T, Zhang Z, Yang J, McLaughlin SH, Schwab J, Scheres SHW, Yatskevich S, Barford D. Cryo-EM structure of the complete inner kinetochore of the budding yeast point centromere. SCIENCE ADVANCES 2023; 9:eadg7480. [PMID: 37506202 PMCID: PMC10381965 DOI: 10.1126/sciadv.adg7480] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 06/26/2023] [Indexed: 07/30/2023]
Abstract
The point centromere of budding yeast specifies assembly of the large kinetochore complex to mediate chromatid segregation. Kinetochores comprise the centromere-associated inner kinetochore (CCAN) complex and the microtubule-binding outer kinetochore KNL1-MIS12-NDC80 (KMN) network. The budding yeast inner kinetochore also contains the DNA binding centromere-binding factor 1 (CBF1) and CBF3 complexes. We determined the cryo-electron microscopy structure of the yeast inner kinetochore assembled onto the centromere-specific centromere protein A nucleosomes (CENP-ANuc). This revealed a central CENP-ANuc with extensively unwrapped DNA ends. These free DNA duplexes bind two CCAN protomers, one of which entraps DNA topologically, positioned on the centromere DNA element I (CDEI) motif by CBF1. The two CCAN protomers are linked through CBF3 forming an arch-like configuration. With a structural mechanism for how CENP-ANuc can also be linked to KMN involving only CENP-QU, we present a model for inner kinetochore assembly onto a point centromere and how it organizes the outer kinetochore for chromosome attachment to the mitotic spindle.
Collapse
Affiliation(s)
| | | | - Jing Yang
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | | | | | | | | | | |
Collapse
|
12
|
Popchock AR, Larson JD, Dubrulle J, Asbury CL, Biggins S. Direct observation of coordinated assembly of individual native centromeric nucleosomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.20.524981. [PMID: 36711558 PMCID: PMC9882320 DOI: 10.1101/2023.01.20.524981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Eukaryotic chromosome segregation requires the kinetochore, a megadalton-sized machine that forms on specialized centromeric chromatin containing CENP-A, a histone H3 variant. CENP-A deposition requires a chaperone protein HJURP that targets it to the centromere, but it has remained unclear whether HJURP has additional functions beyond CENP-A targeting and why high AT DNA content, which disfavors nucleosome assembly, is widely conserved at centromeres. To overcome the difficulties of studying nucleosome formation in vivo, we developed a microscopy assay that enables direct observation of de novo centromeric nucleosome recruitment and maintenance with single molecule resolution. Using this assay, we discover that CENP-A can arrive at centromeres without its dedicated centromere-specific chaperone HJURP, but stable incorporation depends on HJURP and additional DNA-binding proteins of the inner kinetochore. We also show that homopolymer AT runs in the yeast centromeres are essential for efficient CENP-A deposition. Together, our findings reveal requirements for stable nucleosome formation and provide a foundation for further studies of the assembly and dynamics of native kinetochore complexes.
Collapse
Affiliation(s)
- Andrew R. Popchock
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Joshua D. Larson
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA
| | - Julien Dubrulle
- Shared Resources, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Charles L. Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| |
Collapse
|
13
|
Wozny MR, Di Luca A, Morado DR, Picco A, Khaddaj R, Campomanes P, Ivanović L, Hoffmann PC, Miller EA, Vanni S, Kukulski W. In situ architecture of the ER-mitochondria encounter structure. Nature 2023:10.1038/s41586-023-06050-3. [PMID: 37165187 DOI: 10.1038/s41586-023-06050-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 04/04/2023] [Indexed: 05/12/2023]
Abstract
The endoplasmic reticulum and mitochondria are main hubs of eukaryotic membrane biogenesis that rely on lipid exchange via membrane contact sites1-3, but the underpinning mechanisms remain poorly understood. In yeast, tethering and lipid transfer between the two organelles is mediated by the endoplasmic reticulum-mitochondria encounter structure (ERMES), a four-subunit complex of unresolved stoichiometry and architecture4-6. Here we determined the molecular organization of ERMES within Saccharomyces cerevisiae cells using integrative structural biology by combining quantitative live imaging, cryo-correlative microscopy, subtomogram averaging and molecular modelling. We found that ERMES assembles into approximately 25 discrete bridge-like complexes distributed irregularly across a contact site. Each bridge consists of three synaptotagmin-like mitochondrial lipid binding protein domains oriented in a zig-zag arrangement. Our molecular model of ERMES reveals a pathway for lipids. These findings resolve the in situ supramolecular architecture of a major inter-organelle lipid transfer machinery and provide a basis for the mechanistic understanding of lipid fluxes in eukaryotic cells.
Collapse
Affiliation(s)
- Michael R Wozny
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Andrea Di Luca
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Dustin R Morado
- MRC Laboratory of Molecular Biology, Cambridge, UK
- SciLifeLab, Solna, Sweden
- Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Andrea Picco
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
| | - Rasha Khaddaj
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | - Pablo Campomanes
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Lazar Ivanović
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Patrick C Hoffmann
- MRC Laboratory of Molecular Biology, Cambridge, UK
- Max Planck Institute of Biophysics, Frankfurt am Main, Germany
| | | | - Stefano Vanni
- Department of Biology, University of Fribourg, Fribourg, Switzerland.
| | - Wanda Kukulski
- MRC Laboratory of Molecular Biology, Cambridge, UK.
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland.
| |
Collapse
|
14
|
McAinsh AD, Kops GJPL. Principles and dynamics of spindle assembly checkpoint signalling. Nat Rev Mol Cell Biol 2023:10.1038/s41580-023-00593-z. [PMID: 36964313 DOI: 10.1038/s41580-023-00593-z] [Citation(s) in RCA: 53] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/22/2023] [Indexed: 03/26/2023]
Abstract
The transmission of a complete set of chromosomes to daughter cells during cell division is vital for development and tissue homeostasis. The spindle assembly checkpoint (SAC) ensures correct segregation by informing the cell cycle machinery of potential errors in the interactions of chromosomes with spindle microtubules prior to anaphase. To do so, the SAC monitors microtubule engagement by specialized structures known as kinetochores and integrates local mechanical and chemical cues such that it can signal in a sensitive, responsive and robust manner. In this Review, we discuss how SAC proteins interact to allow production of the mitotic checkpoint complex (MCC) that halts anaphase progression by inhibiting the anaphase-promoting complex/cyclosome (APC/C). We highlight recent advances aimed at understanding the dynamic signalling properties of the SAC and how it interprets various naturally occurring intermediate attachment states. Further, we discuss SAC signalling in the context of the mammalian multisite kinetochore and address the impact of the fibrous corona. We also identify current challenges in understanding how the SAC ensures high-fidelity chromosome segregation.
Collapse
Affiliation(s)
- Andrew D McAinsh
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK.
- Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
| | - Geert J P L Kops
- Hubrecht Institute - KNAW (Royal Netherlands Academy of Arts and Sciences) and University Medical Centre Utrecht, Utrecht, The Netherlands.
- Oncode Institute, Utrecht, The Netherlands.
| |
Collapse
|
15
|
Radhakrishnan RM, Kizhakkeduth ST, Nair VM, Ayyappan S, Lakshmi RB, Babu N, Prasannajith A, Umeda K, Vijayan V, Kodera N, Manna TK. Kinetochore-microtubule attachment in human cells is regulated by the interaction of a conserved motif of Ska1 with EB1. J Biol Chem 2023; 299:102853. [PMID: 36592928 PMCID: PMC9926122 DOI: 10.1016/j.jbc.2022.102853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 01/02/2023] Open
Abstract
The kinetochore establishes the linkage between chromosomes and the spindle microtubule plus ends during mitosis. In vertebrates, the spindle-kinetochore-associated (Ska1,2,3) complex stabilizes kinetochore attachment with the microtubule plus ends, but how Ska is recruited to and stabilized at the kinetochore-microtubule interface is not understood. Here, our results show that interaction of Ska1 with the general microtubule plus end-associated protein EB1 through a conserved motif regulates Ska recruitment to kinetochores in human cells. Ska1 forms a stable complex with EB1 via interaction with the motif in its N-terminal disordered loop region. Disruption of this interaction either by deleting or mutating the motif disrupts Ska complex recruitment to kinetochores and induces chromosome alignment defects, but it does not affect Ska complex assembly. Atomic-force microscopy imaging revealed that Ska1 is anchored to the C-terminal region of the EB1 dimer through its loop and thereby promotes formation of extended structures. Furthermore, our NMR data showed that the Ska1 motif binds to the residues in EB1 that are the binding sites of other plus end targeting proteins that are recruited to microtubules by EB1 through a similar conserved motif. Collectively, our results demonstrate that EB1-mediated Ska1 recruitment onto the microtubule serves as a general mechanism for the formation of vertebrate kinetochore-microtubule attachments and metaphase chromosome alignment.
Collapse
Affiliation(s)
- Renjith M Radhakrishnan
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Safwa T Kizhakkeduth
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Vishnu M Nair
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Shine Ayyappan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - R Bhagya Lakshmi
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Neethu Babu
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Anjaly Prasannajith
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Kenichi Umeda
- Nano Life Science Institute (WPI-Nano LSI), Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Vinesh Vijayan
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India
| | - Noriyuki Kodera
- Nano Life Science Institute (WPI-Nano LSI), Kanazawa University, Kakuma-machi, Kanazawa, Japan
| | - Tapas K Manna
- School of Biology, Indian Institute of Science Education and Research, Thiruvananthapuram, Kerala, India.
| |
Collapse
|
16
|
Virant D, Vojnovic I, Winkelmeier J, Endesfelder M, Turkowyd B, Lando D, Endesfelder U. Unraveling the kinetochore nanostructure in Schizosaccharomyces pombe using multi-color SMLM imaging. J Cell Biol 2023; 222:213836. [PMID: 36705602 PMCID: PMC9930162 DOI: 10.1083/jcb.202209096] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 12/20/2022] [Accepted: 12/27/2022] [Indexed: 01/28/2023] Open
Abstract
The key to ensuring proper chromosome segregation during mitosis is the kinetochore (KT), a tightly regulated multiprotein complex that links the centromeric chromatin to the spindle microtubules and as such leads the segregation process. Understanding its architecture, function, and regulation is therefore essential. However, due to its complexity and dynamics, only its individual subcomplexes could be studied in structural detail so far. In this study, we construct a nanometer-precise in situ map of the human-like regional KT of Schizosaccharomyces pombe using multi-color single-molecule localization microscopy. We measure each protein of interest (POI) in conjunction with two references, cnp1CENP-A at the centromere and sad1 at the spindle pole. This allows us to determine cell cycle and mitotic plane, and to visualize individual centromere regions separately. We determine protein distances within the complex using Bayesian inference, establish the stoichiometry of each POI and, consequently, build an in situ KT model with unprecedented precision, providing new insights into the architecture.
Collapse
Affiliation(s)
- David Virant
- https://ror.org/05r7n9c40Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiologyand LOEWE Center for Synthetic Microbiology, Marburg, Germany
| | - Ilijana Vojnovic
- https://ror.org/05r7n9c40Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiologyand LOEWE Center for Synthetic Microbiology, Marburg, Germany,Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA,Institute for Microbiology and Biotechnology, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Jannik Winkelmeier
- https://ror.org/05r7n9c40Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiologyand LOEWE Center for Synthetic Microbiology, Marburg, Germany,Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA,Institute for Microbiology and Biotechnology, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Marc Endesfelder
- https://ror.org/05591te55Institute for Assyriology and Hittitology, Ludwig-Maximilians-Universität München, München, Germany
| | - Bartosz Turkowyd
- https://ror.org/05r7n9c40Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiologyand LOEWE Center for Synthetic Microbiology, Marburg, Germany,Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA,Institute for Microbiology and Biotechnology, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - David Lando
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Ulrike Endesfelder
- https://ror.org/05r7n9c40Department of Systems and Synthetic Microbiology, Max Planck Institute for Terrestrial Microbiologyand LOEWE Center for Synthetic Microbiology, Marburg, Germany,Department of Physics, Carnegie Mellon University, Pittsburgh, PA, USA,Institute for Microbiology and Biotechnology, Rheinische-Friedrich-Wilhelms-Universität Bonn, Bonn, Germany,Correspondence to Ulrike Endesfelder:
| |
Collapse
|
17
|
Cieslinski K, Wu YL, Nechyporenko L, Hörner SJ, Conti D, Skruzny M, Ries J. Nanoscale structural organization and stoichiometry of the budding yeast kinetochore. J Cell Biol 2023; 222:213833. [PMID: 36705601 PMCID: PMC9929930 DOI: 10.1083/jcb.202209094] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/16/2022] [Accepted: 12/27/2022] [Indexed: 01/28/2023] Open
Abstract
Proper chromosome segregation is crucial for cell division. In eukaryotes, this is achieved by the kinetochore, an evolutionarily conserved multiprotein complex that physically links the DNA to spindle microtubules and takes an active role in monitoring and correcting erroneous spindle-chromosome attachments. Our mechanistic understanding of these functions and how they ensure an error-free outcome of mitosis is still limited, partly because we lack a complete understanding of the kinetochore structure in the cell. In this study, we use single-molecule localization microscopy to visualize individual kinetochore complexes in situ in budding yeast. For major kinetochore proteins, we measured their abundance and position within the metaphase kinetochore. Based on this comprehensive dataset, we propose a quantitative model of the budding yeast kinetochore. While confirming many aspects of previous reports based on bulk imaging, our results present a unifying nanoscale model of the kinetochore in budding yeast.
Collapse
Affiliation(s)
- Konstanty Cieslinski
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany,Translational Radiation Oncology Unit, Deutsches Krebsforschungszentrum, Heidelberg, Germany
| | - Yu-Le Wu
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany,Faculty of Biosciences, Collaboration for Joint PhD Degree Between European Molecular Biology Laboratory and Heidelberg University, Heidelberg, Germany
| | - Lisa Nechyporenko
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany,Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Heidelberg, Germany
| | - Sarah Janice Hörner
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany,https://ror.org/04p61dj41Institute of Molecular and Cell Biology, Mannheim University of Applied Sciences, Mannheim, Germany,Interdisciplinary Center for Neuroscience, Heidelberg University, Heidelberg, Germany
| | - Duccio Conti
- https://ror.org/03vpj4s62Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Michal Skruzny
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Jonas Ries
- https://ror.org/03mstc592Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| |
Collapse
|
18
|
Meier SM, Farcas AM, Kumar A, Ijavi M, Bill RT, Stelling J, Dufresne ER, Steinmetz MO, Barral Y. Multivalency ensures persistence of a +TIP body at specialized microtubule ends. Nat Cell Biol 2023; 25:56-67. [PMID: 36536177 PMCID: PMC9859758 DOI: 10.1038/s41556-022-01035-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 10/21/2022] [Indexed: 12/24/2022]
Abstract
Microtubule plus-end tracking proteins (+TIPs) control microtubule specialization and are as such essential for cell division and morphogenesis. Here we investigated interactions and functions of the budding yeast Kar9 network consisting of the core +TIP proteins Kar9 (functional homologue of APC, MACF and SLAIN), Bim1 (orthologous to EB1) and Bik1 (orthologous to CLIP-170). A multivalent web of redundant interactions links the three +TIPs together to form a '+TIP body' at the end of chosen microtubules. This body behaves as a liquid condensate that allows it to persist on both growing and shrinking microtubule ends, and to function as a mechanical coupling device between microtubules and actin cables. Our study identifies nanometre-scale condensates as effective cellular structures and underlines the power of dissecting the web of low-affinity interactions driving liquid-liquid phase separation in order to establish how condensation processes support cell function.
Collapse
Affiliation(s)
- Sandro M Meier
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Villigen, Switzerland
- Department of Biology, Institute of Biochemistry, ETH Zürich, Zürich, Switzerland
- Bringing Materials to Life Initiative, ETH Zürich, Zürich, Switzerland
| | - Ana-Maria Farcas
- Department of Biology, Institute of Biochemistry, ETH Zürich, Zürich, Switzerland
- Bringing Materials to Life Initiative, ETH Zürich, Zürich, Switzerland
| | - Anil Kumar
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Villigen, Switzerland
- ImmunOs Therapeutics AG, Schlieren, Switzerland
| | - Mahdiye Ijavi
- Bringing Materials to Life Initiative, ETH Zürich, Zürich, Switzerland
- Department of Materials, ETH Zürich, Zürich, Switzerland
| | - Robert T Bill
- Department of Biology, Institute of Biochemistry, ETH Zürich, Zürich, Switzerland
- Department of Molecular Life Sciences, University of Zürich, Zürich, Switzerland
| | - Jörg Stelling
- Department of Biosystems Science and Engineering and SIB Swiss Institute of Bioinformatics, ETH Zürich, Basel, Switzerland
| | - Eric R Dufresne
- Bringing Materials to Life Initiative, ETH Zürich, Zürich, Switzerland
- Department of Materials, ETH Zürich, Zürich, Switzerland
| | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Villigen, Switzerland.
- University of Basel, Biozentrum, Basel, Switzerland.
| | - Yves Barral
- Department of Biology, Institute of Biochemistry, ETH Zürich, Zürich, Switzerland.
- Bringing Materials to Life Initiative, ETH Zürich, Zürich, Switzerland.
| |
Collapse
|
19
|
Kakimoto-Takeda Y, Kojima R, Shiino H, Shinmyo M, Kurokawa K, Nakano A, Endo T, Tamura Y. Dissociation of ERMES clusters plays a key role in attenuating the endoplasmic reticulum stress. iScience 2022; 25:105362. [PMID: 36339260 PMCID: PMC9626684 DOI: 10.1016/j.isci.2022.105362] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 08/24/2022] [Accepted: 10/12/2022] [Indexed: 11/27/2022] Open
Abstract
In yeast, ERMES, which mediates phospholipid transport between the ER and mitochondria, forms a limited number of oligomeric clusters at ER-mitochondria contact sites in a cell. Although the number of the ERMES clusters appears to be regulated to maintain proper inter-organelle phospholipid trafficking, its underlying mechanism and physiological relevance remain poorly understood. Here, we show that mitochondrial dynamics control the number of ERMES clusters. Moreover, we find that ER stress causes dissociation of the ERMES clusters independently of Ire1 and Hac1, canonical ER-stress response pathway components, leading to a delay in the phospholipid transport from the ER to mitochondria. Our biochemical and genetic analyses strongly suggest that the impaired phospholipid transport contributes to phospholipid accumulation in the ER, expanding the ER for ER stress attenuation. We thus propose that the ERMES dissociation constitutes an overlooked pathway of the ER stress response that operates in addition to the canonical Ire1/Hac1-dependent pathway. Mitochondrial fusion and division regulate the clustering of the ERMES complex ER stress leads to dissociation of the ERMES clusters independently of Ire1 and Hac1 The dissociated ERMES complexes have less activity in transporting phospholipids The defective phospholipid transport may cause the ER expansion to relieve ER stress
Collapse
Affiliation(s)
- Yuriko Kakimoto-Takeda
- Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, 2-2-2 Iidanishi, Yamagata 990-9585, Japan
| | - Rieko Kojima
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Hiroya Shiino
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Manatsu Shinmyo
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Toshiya Endo
- Faculty of Life Sciences, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto 603-8555, Japan
- Institute for Protein Dynamics, Kyoto Sangyo University, Kamigamo-motoyama, Kita-ku, Kyoto 603-8555, Japan
| | - Yasushi Tamura
- Faculty of Science, Yamagata University, 1-4-12 Kojirakawa-machi, Yamagata 990-8560, Japan
- Corresponding author
| |
Collapse
|
20
|
Kucharski TJ, Hards R, Vandal SE, Abad MA, Jeyaprakash AA, Kaye E, al-Rawi A, Ly T, Godek KM, Gerber SA, Compton DA. Small changes in phospho-occupancy at the kinetochore-microtubule interface drive mitotic fidelity. J Cell Biol 2022; 221:213364. [PMID: 35878017 PMCID: PMC9351707 DOI: 10.1083/jcb.202107107] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Revised: 04/19/2022] [Accepted: 07/05/2022] [Indexed: 01/24/2023] Open
Abstract
Kinetochore protein phosphorylation promotes the correction of erroneous microtubule attachments to ensure faithful chromosome segregation during cell division. Determining how phosphorylation executes error correction requires an understanding of whether kinetochore substrates are completely (i.e., all-or-none) or only fractionally phosphorylated. Using quantitative mass spectrometry (MS), we measured phospho-occupancy on the conserved kinetochore protein Hec1 (NDC80) that directly binds microtubules. None of the positions measured exceeded ∼50% phospho-occupancy, and the cumulative phospho-occupancy changed by only ∼20% in response to changes in microtubule attachment status. The narrow dynamic range of phospho-occupancy is maintained, in part, by the ongoing phosphatase activity. Further, both Cdk1-Cyclin B1 and Aurora kinases phosphorylate Hec1 to enhance error correction in response to different types of microtubule attachment errors. The low inherent phospho-occupancy promotes microtubule attachment to kinetochores while the high sensitivity of kinetochore-microtubule attachments to small changes in phospho-occupancy drives error correction and ensures high mitotic fidelity.
Collapse
Affiliation(s)
- Thomas J. Kucharski
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Rufus Hards
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Sarah E. Vandal
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Maria Alba Abad
- Wellcome Centre For Cell Biology, University of Edinburgh, Edinburgh, UK
| | | | - Edward Kaye
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Aymen al-Rawi
- Wellcome Centre For Cell Biology, University of Edinburgh, Edinburgh, UK
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Tony Ly
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, UK
| | - Kristina M. Godek
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
| | - Scott A. Gerber
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
| | - Duane A. Compton
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH
- Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH
- Correspondence to Duane A. Compton:
| |
Collapse
|
21
|
Menon D, Hummel D, Kaksonen M. Regulation of membrane scission in yeast endocytosisDepartment of Biochemistry and National Centre of Competence in Research, Chemical Biology, University of Geneva, Geneva, Switzerland. Mol Biol Cell 2022; 33:ar114. [PMID: 35976707 DOI: 10.1091/mbc.e21-07-0346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
During clathrin-mediated endocytosis, a flat plasma membrane is shaped into an invagination that undergoes scission to form a vesicle. In mammalian cells, the force that drives the transition from invagination to vesicle is primarily provided by the GTPase dynamin that acts in concert with crescent-shaped BAR domain proteins. In yeast cells, the mechanism of endocytic scission is unclear. The yeast BAR domain protein complex Rvs161/167 (Rvs) nevertheless plays an important role in this process: deletion of Rvs dramatically reduces scission efficiency. A mechanistic understanding of the influence of Rvs on scission however, remains incomplete. We used quantitative live-cell imaging and genetic manipulation to understand the recruitment and function of Rvs and other late-stage proteins at yeast endocytic sites. We found that arrival of Rvs at endocytic sites is timed by interaction of its BAR domain with specific membrane curvature. A second domain of Rvs167 - the SH3 domain - affects localization efficiency of Rvs. We show that Myo3, one of the two type-I myosins in Saccharomyces cerevisiae, has a role in recruiting Rvs167 via the SH3 domain. Removal of the SH3 domain also affects assembly and disassembly of actin and impedes membrane invagination. Our results indicate that both BAR and SH3 domains are important for the role of Rvs as a regulator of scission. We tested other proteins implicated in vesicle formation in Saccharomyces cerevisiae, and found that neither synaptojanins nor dynamin contribute directly to membrane scission. We propose that recruitment of Rvs BAR domains delays scission and allows invaginations to grow by stabilizing them. We also propose that vesicle formation is dependent on the force exerted by the actin network.
Collapse
Affiliation(s)
- Deepikaa Menon
- Department of Biochemistry and National Centre of Competence in Research, Chemical Biology, University of Geneva, Geneva, Switzerland
| | - Daniel Hummel
- Department of Biochemistry and National Centre of Competence in Research, Chemical Biology, University of Geneva, Geneva, Switzerland
| | - Marko Kaksonen
- Department of Biochemistry and National Centre of Competence in Research, Chemical Biology, University of Geneva, Geneva, Switzerland
| |
Collapse
|
22
|
Flores RL, Peterson ZE, Zelter A, Riffle M, Asbury CL, Davis TN. Three interacting regions of the Ndc80 and Dam1 complexes support microtubule tip-coupling under load. J Cell Biol 2022; 221:213102. [PMID: 35353161 DOI: 10.1083/jcb.202107016] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 12/20/2021] [Accepted: 03/07/2022] [Indexed: 01/15/2023] Open
Abstract
Accurate mitosis requires kinetochores to make persistent, load-bearing attachments to dynamic microtubule tips, thereby coupling chromosome movements to tip growth and shortening. This tip-coupling behavior depends on the conserved Ndc80 complex and, in budding yeast, on the Dam1 complex, which bind each other directly via three distinct interacting regions. The functional relevance of these multiple interactions was mysterious. Here we show that interactions between two of these regions support the high rupture strengths that occur when applied force is rapidly increased and also support the stability of tip-coupling when force is held constant over longer durations. The contribution of either of these two regions to tip-coupling is reduced by phosphorylation by Aurora B kinase. The third interaction region makes no apparent contribution to rupture strength, but its phosphorylation by Aurora B kinase specifically decreases the long-term stability of tip-coupling. The specific reduction of long-term stability relative to short-term strength might have important implications for mitotic error correction.
Collapse
Affiliation(s)
- Rachel L Flores
- Department of Biochemistry, University of Washington, Seattle, WA
| | | | - Alex Zelter
- Department of Biochemistry, University of Washington, Seattle, WA
| | - Michael Riffle
- Department of Biochemistry, University of Washington, Seattle, WA
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, WA
| |
Collapse
|
23
|
Liao M, Kuo YW, Howard J. Counting fluorescently labeled proteins in tissues in the spinning disk microscope using single-molecule calibrations. Mol Biol Cell 2022; 33:ar48. [PMID: 35323029 PMCID: PMC9265152 DOI: 10.1091/mbc.e21-12-0618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Quantification of molecular numbers and concentrations in living cells is critical for testing models of complex biological phenomena. Counting molecules in cells requires estimation of the fluorescence intensity of single molecules, which is generally limited to imaging near cell surfaces, in isolated cells, or where motions are diffusive. To circumvent this difficulty, we have devised a calibration technique for spinning–disk confocal microscopy, commonly used for imaging in tissues, that uses single–step bleaching kinetics to estimate the single–fluorophore intensity. To cross–check our calibrations, we compared the brightness of fluorophores in the SDC microscope to those in the total internal reflection and epifluorescence microscopes. We applied this calibration method to quantify the number of end–binding protein 1 (EB1)–eGFP in the comets of growing microtubule ends and to measure the cytoplasmic concentration of EB1–eGFP in sensory neurons in fly larvae. These measurements allowed us to estimate the dissociation constant of EB1–eGFP from the microtubules as well as the GTP–tubulin cap size. Our results show the unexplored potential of single–molecule imaging using spinning–disk confocal microscopy and provide a straightforward method to count the absolute number of fluorophores in tissues that can be applied to a wide range of biological systems and imaging techniques.
Collapse
Affiliation(s)
- Maijia Liao
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Yin-Wei Kuo
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Jonathon Howard
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| |
Collapse
|
24
|
Abstract
The centromere serves as the binding site for the kinetochore and is essential for the faithful segregation of chromosomes throughout cell division. The point centromere in yeast is encoded by a ∼115 bp specific DNA sequence, whereas regional centromeres range from 6-10 kbp in fission yeast to 5-10 Mbp in humans. Understanding the physical structure of centromere chromatin (pericentromere in yeast), defined as the chromatin between sister kinetochores, will provide fundamental insights into how centromere DNA is woven into a stiff spring that is able to resist microtubule pulling forces during mitosis. One hallmark of the pericentromere is the enrichment of the structural maintenance of chromosome (SMC) proteins cohesin and condensin. Based on studies from population approaches (ChIP-seq and Hi-C) and experimentally obtained images of fluorescent probes of pericentromeric structure, as well as quantitative comparisons between simulations and experimental results, we suggest a mechanism for building tension between sister kinetochores. We propose that the centromere is a chromatin bottlebrush that is organized by the loop-extruding proteins condensin and cohesin. The bottlebrush arrangement provides a biophysical means to transform pericentromeric chromatin into a spring due to the steric repulsion between radial loops. We argue that the bottlebrush is an organizing principle for chromosome organization that has emerged from multiple approaches in the field.
Collapse
|
25
|
Roy B, Sim J, Han SJY, Joglekar AP. Kre28-Spc105 interaction is essential for Spc105 loading at the kinetochore. Open Biol 2022; 12:210274. [PMID: 35042402 PMCID: PMC8767186 DOI: 10.1098/rsob.210274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 11/18/2021] [Indexed: 11/12/2022] Open
Abstract
Kinetochore (KTs) are macromolecular protein assemblies that attach sister chromatids to spindle microtubules (MTs) and mediate accurate chromosome segregation during mitosis. The outer KT consists of the KMN network, a protein super-complex comprising Knl1 (yeast Spc105), Mis12 (yeast Mtw1), and Ndc80 (yeast Ndc80), which harbours sites for MT binding. Within the KMN network, Spc105 acts as an interaction hub of components involved in spindle assembly checkpoint (SAC) signalling. It is known that Spc105 forms a complex with KT component Kre28. However, where Kre28 physically localizes in the budding yeast KT is not clear. The exact function of Kre28 at the KT is also unknown. Here, we investigate how Spc105 and Kre28 interact and how they are organized within bioriented yeast KTs using genetics and cell biological experiments. Our microscopy data show that Spc105 and Kre28 localize at the KT with a 1 : 1 stoichiometry. We also show that the Kre28-Spc105 interaction is important for Spc105 protein turn-over and essential for their mutual recruitment at the KTs. We created several truncation mutants of kre28 that affect Spc105 loading at the KTs. When over-expressed, these mutants sustain the cell viability, but SAC signalling and KT biorientation are impaired. Therefore, we conclude that Kre28 contributes to chromosome biorientation and high-fidelity segregation at least indirectly by regulating Spc105 localization at the KTs.
Collapse
Affiliation(s)
- Babhrubahan Roy
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Janice Sim
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Simon J. Y. Han
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Ajit P. Joglekar
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA
| |
Collapse
|
26
|
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.
Collapse
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
| |
Collapse
|
27
|
Walstein K, Petrovic A, Pan D, Hagemeier B, Vogt D, Vetter IR, Musacchio A. Assembly principles and stoichiometry of a complete human kinetochore module. SCIENCE ADVANCES 2021; 7:7/27/eabg1037. [PMID: 34193424 PMCID: PMC8245036 DOI: 10.1126/sciadv.abg1037] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 05/14/2021] [Indexed: 05/03/2023]
Abstract
Centromeres are epigenetically determined chromosomal loci that seed kinetochore assembly to promote chromosome segregation during cell division. CENP-A, a centromere-specific histone H3 variant, establishes the foundations for centromere epigenetic memory and kinetochore assembly. It recruits the constitutive centromere-associated network (CCAN), which in turn assembles the microtubule-binding interface. How the specific organization of centromeric chromatin relates to kinetochore assembly and to centromere identity through cell division remains conjectural. Here, we break new ground by reconstituting a functional full-length version of CENP-C, the largest human CCAN subunit and a blueprint of kinetochore assembly. We show that full-length CENP-C, a dimer, binds stably to two nucleosomes and permits further assembly of all other kinetochore subunits in vitro with relative ratios closely matching those of endogenous human kinetochores. Our results imply that human kinetochores emerge from clustering multiple copies of a fundamental module and may have important implications for transgenerational inheritance of centromeric chromatin.
Collapse
Affiliation(s)
- Kai Walstein
- 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 1, 45141 Essen, Germany
| | - Arsen Petrovic
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Dongqing Pan
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Birte Hagemeier
- 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
| | - 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.
- Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstraße 1, 45141 Essen, Germany
| |
Collapse
|
28
|
Chen J, Xiong Z, Miller DE, Yu Z, McCroskey S, Bradford WD, Cavanaugh AM, Jaspersen SL. The role of gene dosage in budding yeast centrosome scaling and spontaneous diploidization. PLoS Genet 2020; 16:e1008911. [PMID: 33332348 PMCID: PMC7775121 DOI: 10.1371/journal.pgen.1008911] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 12/31/2020] [Accepted: 11/03/2020] [Indexed: 12/12/2022] Open
Abstract
Ploidy is the number of whole sets of chromosomes in a species. Ploidy is typically a stable cellular feature that is critical for survival. Polyploidization is a route recognized to increase gene dosage, improve fitness under stressful conditions and promote evolutionary diversity. However, the mechanism of regulation and maintenance of ploidy is not well characterized. Here, we examine the spontaneous diploidization associated with mutations in components of the Saccharomyces cerevisiae centrosome, known as the spindle pole body (SPB). Although SPB mutants are associated with defects in spindle formation, we show that two copies of the mutant in a haploid yeast favors diploidization in some cases, leading us to speculate that the increased gene dosage in diploids ‘rescues’ SPB duplication defects, allowing cells to successfully propagate with a stable diploid karyotype. This copy number-based rescue is linked to SPB scaling: certain SPB subcomplexes do not scale or only minimally scale with ploidy. We hypothesize that lesions in structures with incompatible allometries such as the centrosome may drive changes such as whole genome duplication, which have shaped the evolutionary landscape of many eukaryotes. Ploidy is the number of whole sets of chromosomes in a species. Most eukaryotes alternate between a diploid (two copy) and haploid (one copy) state during their life and sexual cycle. However, as part of normal human development, specific tissues increase their DNA content. This gain of entire sets of chromosomes is known as polyploidization, and it is observed in invertebrates, plants and fungi, as well. Polyploidy is thought to improve fitness under stressful conditions and promote evolutionary diversity, but how ploidy is determined is poorly understood. Here, we use budding yeast to investigate mechanisms underlying the ploidy of wild-type cells and specific mutants that affect the centrosome, a conserved structure involved in chromosome segregation during cell division. Our work suggests that different scaling relationships (allometry) between the genome and cellular structures underlies alterations in ploidy. Furthermore, mutations in cellular structures with incompatible allometric relationships with the genome may drive genomic changes such duplications, which are underly the evolution of many species including both yeasts and humans.
Collapse
Affiliation(s)
- Jingjing Chen
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Zhiyong Xiong
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Danny E. Miller
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Zulin Yu
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Scott McCroskey
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - William D. Bradford
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Ann M. Cavanaugh
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
| | - Sue L. Jaspersen
- Stowers Institute for Medical Research, Kansas City, Missouri, United States of America
- Department of Molecular and Integrative Physiology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
- * E-mail:
| |
Collapse
|
29
|
Gutierrez A, Kim JO, Umbreit NT, Asbury CL, Davis TN, Miller MP, Biggins S. Cdk1 Phosphorylation of the Dam1 Complex Strengthens Kinetochore-Microtubule Attachments. Curr Biol 2020; 30:4491-4499.e5. [PMID: 32946748 PMCID: PMC7497780 DOI: 10.1016/j.cub.2020.08.054] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 07/20/2020] [Accepted: 08/14/2020] [Indexed: 12/01/2022]
Abstract
To ensure the faithful inheritance of DNA, a macromolecular protein complex called the kinetochore sustains the connection between chromosomes and force-generating dynamic microtubules during cell division. Defects in this process lead to aneuploidy, a common feature of cancer cells and the cause of many developmental diseases [1, 2, 3, 4]. One of the major microtubule-binding activities in the kinetochore is mediated by the conserved Ndc80 complex (Ndc80c) [5, 6, 7]. In budding yeast, the retention of kinetochores on dynamic microtubule tips also depends on the essential heterodecameric Dam1 complex (Dam1c) [8, 9, 10, 11, 12, 13, 14, 15], which binds to the Ndc80c and is proposed to be a functional ortholog of the metazoan Ska complex [16, 17]. The load-bearing activity of the Dam1c depends on its ability to oligomerize, and the purified complex spontaneously self-assembles into microtubule-encircling oligomeric rings, which are proposed to function as collars that allow kinetochores to processively track the plus-end tips of microtubules and harness the forces generated by disassembling microtubules [10, 11, 12, 13, 14, 15, 18, 19, 20, 21, 22]. However, it is unknown whether there are specific regulatory events that promote Dam1c oligomerization to ensure accurate segregation. Here, we used a reconstitution system to discover that Cdk1, the major mitotic kinase that drives the cell cycle, phosphorylates the Ask1 component of the Dam1c to increase its residence time on microtubules and enhance kinetochore-microtubule attachment strength. We propose that Cdk1 activity promotes Dam1c oligomerization to ensure that kinetochore-microtubule attachments are stabilized as kinetochores come under tension in mitosis. Cdk1 phosphorylation of Dam1c strengthens kinetochore-microtubule attachments Ask1 is the key Cdk1 target in Dam1c that enhances for kinetochore-microtubule attachments Dynamic phosphorylation of Dam1c by Cdk1 is important in vivo Cdk1 phosphorylation of Ask1 appears to promote Dam1c oligomerization
Collapse
Affiliation(s)
- Abraham Gutierrez
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, Seattle, WA 98109, USA; Molecular and Cellular Biology Program, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Jae Ook Kim
- Department of Biochemistry, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Neil T Umbreit
- Department of Biochemistry, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, 1959 NE Pacific Street, Seattle, WA 98195, USA
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, 1705 NE Pacific Street, Seattle, WA 98195, USA
| | - Matthew P Miller
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, Seattle, WA 98109, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, Seattle, WA 98109, USA.
| |
Collapse
|
30
|
Structural view of the yeast Dam1 complex, a ring-shaped molecular coupler for the dynamic microtubule end. Essays Biochem 2020; 64:359-370. [PMID: 32579171 DOI: 10.1042/ebc20190079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 05/25/2020] [Accepted: 05/27/2020] [Indexed: 11/17/2022]
Abstract
In a dividing eukaryotic cell, proper chromosome segregation requires the dynamic yet persistent attachment of kinetochores to spindle microtubules. In the budding yeast Saccharomyces cerevisiae, this function is especially crucial because each kinetochore is attached to a single microtubule; consequently, loss of attachment could lead to unrecoverable chromosome loss. The highly specialized heterodecameric Dam1 protein complex achieves this coupling by assembling into a microtubule-encircling ring that glides near the end of the dynamic microtubule to mediate chromosome motion. In recent years, we have learned a great deal about the structural properties of the Dam1 heterodecamer, its mechanism of self-assembly into rings, and its tethering to the kinetochore by the elongated Ndc80 complex. The most remarkable progress has resulted from defining the fine structures of helical bundles within Dam1 heterodecamer. In this review, we critically analyze structural observations collected by diverse approaches with the goal of obtaining a unified view of Dam1 ring architecture. A considerable consistency between different studies supports a coherent model of the circular core of the Dam1 ring. However, there are persistent uncertainties about the composition of ring protrusions and flexible extensions, as well as their roles in mediating ring core assembly and interactions with the Ndc80 complex and microtubule.
Collapse
|
31
|
A stochastic model for error correction of kinetochore-microtubule attachments in budding yeast. PLoS One 2020; 15:e0236293. [PMID: 32760074 PMCID: PMC7410253 DOI: 10.1371/journal.pone.0236293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 07/01/2020] [Indexed: 12/05/2022] Open
Abstract
To divide replicated chromosomes equally between daughter cells, kinetochores must attach to microtubules emanating from opposite poles of the mitotic spindle (biorientation). An error correction mechanism facilitates this process by destabilizing erroneous kinetochore-microtubule attachments. Here we present a stochastic model of kinetochore-microtubule attachments, via an essential protein Ndc80 in budding yeast, Saccharomyces cerevisiae. Using the model, we calculate the stochastic dynamics of a pair of sister kinetochores as they transition among different attachment states. First of all, we determine the kinase-to-phosphatase balance point that maximizes the probability of biorientation, while starting from an erroneous attachment state. We find that the balance point is sensitive to the rates of microtubule-Ndc80 dissociation and derive an approximate analytical formula that defines the balance point. Secondly, we determine the probability of transition from low-tension amphitelic to monotelic attachment and find that, despite this probability being approximately 33%, biorientation can be achieved with high probability. Thirdly, we calculate the contribution of the geometrical orientation of sister kinetochores to the probability of biorientation and show that, in the absence of geometrical orientation, the biorientation error rate is much larger than that observed in experiments. Finally, we study the coupling of the error correction mechanism to the spindle assembly checkpoint by calculating the average binding of checkpoint-related proteins to the kinetochore during the error correction process.
Collapse
|
32
|
Ustinov NB, Korshunova AV, Gudimchuk NB. Protein Complex NDC80: Properties, Functions, and Possible Role in Pathophysiology of Cell Division. BIOCHEMISTRY (MOSCOW) 2020; 85:448-462. [PMID: 32569552 DOI: 10.1134/s0006297920040057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Mitotic division maintains genetic identity of any multicellular organism throughout an entire lifetime. Each time a parent cell divides, chromosomes are equally distributed between the daughter cells due to the action of mitotic spindle. Mitotic spindle is formed by the microtubules that represent dynamic polymers of tubulin protein. Spindle microtubules are attached end-on to kinetochores - large multi-protein complexes on chromosomes. This review focuses on the four-subunit NDC80 complex, one of the most important kinetochore elements that plays a major role in the attachment of assembling/disassembling microtubule ends to the chromosomes. Here, we summarize published data on the structure, properties, and regulation of the NDC80 complex and discuss possible relationship between changes in the expression of genes coding for the NDC80 complex components, mitotic disorders, and oncogenesis with special emphasis on the diagnostic and therapeutic potential of NDC80.
Collapse
Affiliation(s)
- N B Ustinov
- Center for Theoretical Problems of Physico-Chemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia
| | - A V Korshunova
- Center for Theoretical Problems of Physico-Chemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia.,Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia
| | - N B Gudimchuk
- Center for Theoretical Problems of Physico-Chemical Pharmacology, Russian Academy of Sciences, Moscow, 119991, Russia. .,Lomonosov Moscow State University, Faculty of Physics, Moscow, 119991, Russia
| |
Collapse
|
33
|
Roy B, Han SJ, Fontan AN, Joglekar AP. The copy-number and varied strengths of MELT motifs in Spc105 balance the strength and responsiveness of the spindle assembly checkpoint. eLife 2020; 9:55096. [PMID: 32479259 PMCID: PMC7292645 DOI: 10.7554/elife.55096] [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: 01/12/2020] [Accepted: 05/29/2020] [Indexed: 12/15/2022] Open
Abstract
During mitosis, the Spindle Assembly Checkpoint (SAC) maintains genome stability while also ensuring timely anaphase onset. To maintain genome stability, the SAC must be strong to delay anaphase even if just one chromosome is unattached, but for timely anaphase onset, it must promptly respond to silencing mechanisms. How the SAC meets these potentially antagonistic requirements is unclear. Here we show that the balance between SAC strength and responsiveness is determined by the number of ‘MELT’ motifs in the kinetochore protein Spc105/KNL1 and their Bub3-Bub1 binding affinities. Many strong MELT motifs per Spc105/KNL1 minimize chromosome missegregation, but too many delay anaphase onset. We demonstrate this by constructing a Spc105 variant that trades SAC responsiveness for much more accurate chromosome segregation. We propose that the necessity of balancing SAC strength and responsiveness drives the dual evolutionary trend of the amplification of MELT motif number, but degeneration of their functionally optimal amino acid sequence.
Collapse
Affiliation(s)
- Babhrubahan Roy
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, United States
| | - Simon Jy Han
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, United States
| | - Adrienne Nicole Fontan
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, United States
| | - Ajit P Joglekar
- Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, United States
| |
Collapse
|
34
|
Hamilton GE, Helgeson LA, Noland CL, Asbury CL, Dimitrova YN, Davis TN. Reconstitution reveals two paths of force transmission through the kinetochore. eLife 2020; 9:56582. [PMID: 32406818 PMCID: PMC7367685 DOI: 10.7554/elife.56582] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 05/13/2020] [Indexed: 01/23/2023] Open
Abstract
Partitioning duplicated chromosomes equally between daughter cells is a microtubule-mediated process essential to eukaryotic life. A multi-protein machine, the kinetochore, drives chromosome segregation by coupling the chromosomes to dynamic microtubule tips, even as the tips grow and shrink through the gain and loss of subunits. The kinetochore must harness, transmit, and sense mitotic forces, as a lack of tension signals incorrect chromosome-microtubule attachment and precipitates error correction mechanisms. But though the field has arrived at a ‘parts list’ of dozens of kinetochore proteins organized into subcomplexes, the path of force transmission through these components has remained unclear. Here we report reconstitution of functional Saccharomyces cerevisiae kinetochore assemblies from recombinantly expressed proteins. The reconstituted kinetochores are capable of self-assembling in vitro, coupling centromeric nucleosomes to dynamic microtubules, and withstanding mitotically relevant forces. They reveal two distinct pathways of force transmission and Ndc80c recruitment.
Collapse
Affiliation(s)
- Grace E Hamilton
- Department of Biochemistry, University of Washington, Seattle, United States
| | - Luke A Helgeson
- Department of Biochemistry, University of Washington, Seattle, United States
| | - Cameron L Noland
- Department of Structural Biology, Genentech Inc, South San Francisco, United States
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, United States
| | - Yoana N Dimitrova
- Department of Structural Biology, Genentech Inc, South San Francisco, United States
| | - Trisha N Davis
- Department of Biochemistry, University of Washington, Seattle, United States
| |
Collapse
|
35
|
Roscioli E, Germanova TE, Smith CA, Embacher PA, Erent M, Thompson AI, Burroughs NJ, McAinsh AD. Ensemble-Level Organization of Human Kinetochores and Evidence for Distinct Tension and Attachment Sensors. Cell Rep 2020; 31:107535. [PMID: 32348762 PMCID: PMC7196887 DOI: 10.1016/j.celrep.2020.107535] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Revised: 02/10/2020] [Accepted: 03/27/2020] [Indexed: 12/13/2022] Open
Abstract
Kinetochores are multi-protein machines that form dynamic attachments to microtubules and control chromosome segregation. High fidelity is ensured because kinetochores can monitor attachment status and tension, using this information to activate checkpoints and error-correction mechanisms. To explore how kinetochores achieve this, we used two- and three-color subpixel fluorescence localization to define how proteins from six major complexes (CCAN, MIS12, NDC80, KNL1, RZZ, and SKA) and the checkpoint proteins Bub1, Mad1, and Mad2 are organized in the human kinetochore. This reveals how the outer kinetochore has a high nematic order and is largely invariant to the loss of attachment or tension, except for two mechanical sensors. First, Knl1 unravels to relay tension, and second, NDC80 undergoes jackknifing and loss of nematic order under microtubule detachment, with only the latter wired up to the checkpoint signaling system. This provides insight into how kinetochores integrate mechanical signals to promote error-free chromosome segregation.
Collapse
Affiliation(s)
- Emanuele Roscioli
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Tsvetelina E Germanova
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Christopher A Smith
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Peter A Embacher
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Mathematics Institute, University of Warwick, Coventry, UK
| | - Muriel Erent
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Amelia I Thompson
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK
| | - Nigel J Burroughs
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Mathematics Institute, University of Warwick, Coventry, UK.
| | - Andrew D McAinsh
- Centre for Mechanochemical Cell Biology, University of Warwick, Coventry, UK; Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, UK.
| |
Collapse
|
36
|
Roy B, Verma V, Sim J, Fontan A, Joglekar AP. Delineating the contribution of Spc105-bound PP1 to spindle checkpoint silencing and kinetochore microtubule attachment regulation. J Cell Biol 2019; 218:3926-3942. [PMID: 31649151 PMCID: PMC6891095 DOI: 10.1083/jcb.201810172] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 06/19/2019] [Accepted: 09/18/2019] [Indexed: 02/01/2023] Open
Abstract
Roy et al. highlight a harmful cross-talk that can arise between spindle assembly checkpoint silencing and chromosome biorientation due to the involvement of protein phosphatase 1 in both the processes. Accurate chromosome segregation during cell division requires the spindle assembly checkpoint (SAC), which detects unattached kinetochores, and an error correction mechanism that destabilizes incorrect kinetochore–microtubule attachments. While the SAC and error correction are both regulated by protein phosphatase 1 (PP1), which silences the SAC and stabilizes kinetochore–microtubule attachments, how these distinct PP1 functions are coordinated remains unclear. Here, we investigate the contribution of PP1, docked on its conserved kinetochore receptor Spc105/Knl1, to SAC silencing and attachment regulation. We find that Spc105-bound PP1 is critical for SAC silencing but dispensable for error correction; in fact, reduced PP1 docking on Spc105 improved chromosome segregation and viability of mutant/stressed states. We additionally show that artificially recruiting PP1 to Spc105/Knl1 before, but not after, chromosome biorientation interfered with error correction. These observations lead us to propose that recruitment of PP1 to Spc105/Knl1 is carefully regulated to ensure that chromosome biorientation precedes SAC silencing, thereby ensuring accurate chromosome segregation.
Collapse
Affiliation(s)
- Babhrubahan Roy
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Vikash Verma
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Janice Sim
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Adrienne Fontan
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI
| | - Ajit P Joglekar
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI .,Department of Biophysics, University of Michigan, Ann Arbor, MI
| |
Collapse
|
37
|
Manenschijn HE, Picco A, Mund M, Rivier-Cordey AS, Ries J, Kaksonen M. Type-I myosins promote actin polymerization to drive membrane bending in endocytosis. eLife 2019; 8:44215. [PMID: 31385806 PMCID: PMC6684269 DOI: 10.7554/elife.44215] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 07/23/2019] [Indexed: 12/24/2022] Open
Abstract
Clathrin-mediated endocytosis in budding yeast requires the formation of a dynamic actin network that produces the force to invaginate the plasma membrane against the intracellular turgor pressure. The type-I myosins Myo3 and Myo5 are important for endocytic membrane reshaping, but mechanistic details of their function remain scarce. Here, we studied the function of Myo3 and Myo5 during endocytosis using quantitative live-cell imaging and genetic perturbations. We show that the type-I myosins promote, in a dose-dependent way, the growth and expansion of the actin network, which controls the speed of membrane and coat internalization. We found that this myosin-activity is independent of the actin nucleation promoting activity of myosins, and cannot be compensated for by increasing actin nucleation. Our results suggest a new mechanism for type-I myosins to produce force by promoting actin filament polymerization.
Collapse
Affiliation(s)
- Hetty E Manenschijn
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Andrea Picco
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,NCCR Chemical Biology, University of Geneva, Geneva, Switzerland
| | - Markus Mund
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | | | - Jonas Ries
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Heidelberg, Germany
| | - Marko Kaksonen
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.,NCCR Chemical Biology, University of Geneva, Geneva, Switzerland
| |
Collapse
|
38
|
Guo W, Kumar S, Görlitz F, Garcia E, Alexandrov Y, Munro I, Kelly DJ, Warren S, Thorpe P, Dunsby C, French P. Automated Fluorescence Lifetime Imaging High-Content Analysis of Förster Resonance Energy Transfer between Endogenously Labeled Kinetochore Proteins in Live Budding Yeast Cells. SLAS Technol 2019; 24:308-320. [PMID: 30629461 PMCID: PMC6537140 DOI: 10.1177/2472630318819240] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/16/2018] [Accepted: 11/23/2018] [Indexed: 11/23/2022]
Abstract
We describe an open-source automated multiwell plate fluorescence lifetime imaging (FLIM) methodology to read out Förster resonance energy transfer (FRET) between fluorescent proteins (FPs) labeling endogenous kinetochore proteins (KPs) in live budding yeast cells. The low copy number of many KPs and their small spatial extent present significant challenges for the quantification of donor fluorescence lifetime in the presence of significant cellular autofluorescence and photobleaching. Automated FLIM data acquisition was controlled by µManager and incorporated wide-field time-gated imaging with optical sectioning to reduce background fluorescence. For data analysis, we used custom MATLAB-based software tools to perform kinetochore foci segmentation and local cellular background subtraction and fitted the fluorescence lifetime data using the open-source FLIMfit software. We validated the methodology using endogenous KPs labeled with mTurquoise2 FP and/or yellow FP and measured the donor fluorescence lifetimes for foci comprising 32 kinetochores with KP copy numbers as low as ~2 per kinetochore under an average labeling efficiency of 50%. We observed changes of median donor lifetime ≥250 ps for KPs known to form dimers. Thus, this FLIM high-content analysis platform enables the screening of relatively low-copy-number endogenous protein-protein interactions at spatially confined macromolecular complexes.
Collapse
Affiliation(s)
- Wenjun Guo
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Sunil Kumar
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Frederik Görlitz
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Edwin Garcia
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Yuriy Alexandrov
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| | - Ian Munro
- Photonics Group, Department of Physics,
Imperial College London, London, UK
| | - Douglas J. Kelly
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- RIKEN Center for Biodynamic Systems
Research, Kobe, Japan
| | - Sean Warren
- Garvan Institute of Medical Research,
University of New South Wales, Sydney, New South Wales, Australia
| | - Peter Thorpe
- Francis Crick Institute, London,
UK
- Queen Mary University of London, London,
UK
| | - Christopher Dunsby
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
- Centre for Pathology, Imperial College
London, London, UK
| | - Paul French
- Photonics Group, Department of Physics,
Imperial College London, London, UK
- Francis Crick Institute, London,
UK
| |
Collapse
|
39
|
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.
Collapse
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
| |
Collapse
|
40
|
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.
Collapse
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
| |
Collapse
|
41
|
Hamilton G, Dimitrova Y, Davis TN. Seeing is believing: our evolving view of kinetochore structure, composition, and assembly. Curr Opin Cell Biol 2019; 60:44-52. [PMID: 31078123 DOI: 10.1016/j.ceb.2019.03.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 03/20/2019] [Accepted: 03/28/2019] [Indexed: 11/26/2022]
Abstract
This review highlights three recent trends in the field of kinetochore biology: the proliferation of structural data for kinetochore protein complexes (including CBF3, Dam1c, Mis12cMIND, and CENP-NLChl4/Iml3); the growing consensus that the kinetochore is a dynamic structure whose composition changes as the cell cycle progresses; and the mounting evidence of multiple pathways whereby the microtubule-binding elements of the outer kinetochore may be recruited by inner kinetochore proteins. Our focus is on the two best-studied systems in the field: human and budding yeast kinetochores. This review will demonstrate the remarkable similarity of these two systems, as well as their intriguing differences.
Collapse
Affiliation(s)
- Grace Hamilton
- Department of Biochemistry, University of Washington Box 357350, 1705 NE Pacific St., Seattle, WA 98195-7350, USA
| | - Yoana Dimitrova
- Genentech, Inc., 1 DNA Way, MS: 27, South San Francisco, CA 94080, USA
| | - Trisha N Davis
- Department of Biochemistry, University of Washington Box 357350, 1705 NE Pacific St., Seattle, WA 98195-7350, USA.
| |
Collapse
|
42
|
Plowman R, Singh N, Tromer EC, Payan A, Duro E, Spanos C, Rappsilber J, Snel B, Kops GJPL, Corbett KD, Marston AL. The molecular basis of monopolin recruitment to the kinetochore. Chromosoma 2019; 128:331-354. [PMID: 31037469 PMCID: PMC6823300 DOI: 10.1007/s00412-019-00700-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 03/08/2019] [Accepted: 03/19/2019] [Indexed: 11/29/2022]
Abstract
The monopolin complex is a multifunctional molecular crosslinker, which in S. pombe binds and organises mitotic kinetochores to prevent aberrant kinetochore-microtubule interactions. In the budding yeast S. cerevisiae, whose kinetochores bind a single microtubule, the monopolin complex crosslinks and mono-orients sister kinetochores in meiosis I, enabling the biorientation and segregation of homologs. Here, we show that both the monopolin complex subunit Csm1 and its binding site on the kinetochore protein Dsn1 are broadly distributed throughout eukaryotes, suggesting a conserved role in kinetochore organisation and function. We find that budding yeast Csm1 binds two conserved motifs in Dsn1, one (termed Box 1) representing the ancestral, widely conserved monopolin binding motif and a second (termed Box 2-3) with a likely role in enforcing specificity of sister kinetochore crosslinking. We find that Box 1 and Box 2-3 bind the same conserved hydrophobic cavity on Csm1, suggesting competition or handoff between these motifs. Using structure-based mutants, we also find that both Box 1 and Box 2-3 are critical for monopolin function in meiosis. We identify two conserved serine residues in Box 2-3 that are phosphorylated in meiosis and whose mutation to aspartate stabilises Csm1-Dsn1 binding, suggesting that regulated phosphorylation of these residues may play a role in sister kinetochore crosslinking specificity. Overall, our results reveal the monopolin complex as a broadly conserved kinetochore organiser in eukaryotes, which budding yeast have co-opted to mediate sister kinetochore crosslinking through the addition of a second, regulatable monopolin binding interface.
Collapse
Affiliation(s)
- Rebecca Plowman
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Namit Singh
- Ludwig Institute for Cancer Research, San Diego Branch, La Jolla, CA, 92093, USA.,Synthorx Inc., 11099 North Torrey Pines Road, Suite 290, La Jolla, CA, 92037, USA
| | - Eelco C Tromer
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands.,Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,University Medical Centre Utrecht, Utrecht, The Netherlands.,Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Angel Payan
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, 92093, USA.,Department of Chemistry, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Eris Duro
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Christos Spanos
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK.,Institute of Biotechnology, Technische Universität Berlin, Berlin, Germany
| | - Berend Snel
- Theoretical Biology and Bioinformatics, Biology, Science Faculty, Utrecht University, Utrecht, The Netherlands
| | - Geert J P L Kops
- Oncode Institute, Hubrecht Institute-KNAW (Royal Netherlands Academy of Arts and Sciences), Utrecht, The Netherlands.,University Medical Centre Utrecht, Utrecht, The Netherlands
| | - Kevin D Corbett
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, 92093, USA. .,Department of Chemistry, University of California, San Diego, La Jolla, CA, 92093, USA.
| | - Adele L Marston
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Max Born Crescent, Edinburgh, EH9 3BF, UK.
| |
Collapse
|
43
|
Mukherjee S, Sandri BJ, Tank D, McClellan M, Harasymiw LA, Yang Q, Parker LL, Gardner MK. A Gradient in Metaphase Tension Leads to a Scaled Cellular Response in Mitosis. Dev Cell 2019; 49:63-76.e10. [PMID: 30799228 PMCID: PMC6535804 DOI: 10.1016/j.devcel.2019.01.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 11/20/2018] [Accepted: 01/21/2019] [Indexed: 12/27/2022]
Abstract
During mitosis, motor proteins associate with microtubules to exert pushing forces that establish a mitotic spindle. These pushing forces generate opposing tension in the chromatin that connects oppositely attached sister chromatids, which may then act as a mechanical signal to ensure the fidelity of chromosome segregation during mitosis. However, the role of tension in mitotic cellular signaling remains controversial. In this study, we generated a gradient in tension over multiple isogenic budding yeast cell lines by genetically altering the magnitude of motor-based spindle forces. We found that a decreasing gradient in tension led to an increasing gradient in the rates of kinetochore detachment and anaphase chromosome mis-segregration, and in metaphase time. Simulations and experiments indicated that these tension responses originate from a tension-dependent kinetochore phosphorylation gradient. We conclude that the cell is exquisitely tuned to the magnitude of tension as a signal to detect potential chromosome segregation errors during mitosis.
Collapse
Affiliation(s)
- Soumya Mukherjee
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Brian J Sandri
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Damien Tank
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Mark McClellan
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Lauren A Harasymiw
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Qing Yang
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA
| | - Laurie L Parker
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Melissa K Gardner
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
44
|
Ng CT, Deng L, Chen C, Lim HH, Shi J, Surana U, Gan L. Electron cryotomography analysis of Dam1C/DASH at the kinetochore-spindle interface in situ. J Cell Biol 2018; 218:455-473. [PMID: 30504246 PMCID: PMC6363454 DOI: 10.1083/jcb.201809088] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 10/25/2018] [Accepted: 10/31/2018] [Indexed: 01/01/2023] Open
Abstract
In dividing cells, depolymerizing spindle microtubules move chromosomes by pulling at their kinetochores. While kinetochore subcomplexes have been studied extensively in vitro, little is known about their in vivo structure and interactions with microtubules or their response to spindle damage. Here we combine electron cryotomography of serial cryosections with genetic and pharmacological perturbation to study the yeast chromosome segregation machinery in vivo. Each kinetochore microtubule has one (rarely, two) Dam1C/DASH outer kinetochore assemblies. Dam1C/DASH contacts the microtubule walls and does so with its flexible "bridges"; there are no contacts with the protofilaments' curved tips. In metaphase, ∼40% of the Dam1C/DASH assemblies are complete rings; the rest are partial rings. Ring completeness and binding position along the microtubule are sensitive to kinetochore attachment and tension, respectively. Our study and those of others support a model in which each kinetochore must undergo cycles of conformational change to couple microtubule depolymerization to chromosome movement.
Collapse
Affiliation(s)
- Cai Tong Ng
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore
| | - Li Deng
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore
| | - Chen Chen
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore
| | - Hong Hwa Lim
- Institute of Molecular and Cell Biology Agency for Science Technology and Research, Singapore.,Bioprocessing Technology Institute, Agency for Science Technology and Research, Singapore
| | - Jian Shi
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore
| | - Uttam Surana
- Institute of Molecular and Cell Biology Agency for Science Technology and Research, Singapore.,Bioprocessing Technology Institute, Agency for Science Technology and Research, Singapore.,Department of Pharmacology, National University of Singapore, Singapore
| | - Lu Gan
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore
| |
Collapse
|
45
|
Kyriacou E, Heun P. High-resolution mapping of centromeric protein association using APEX-chromatin fibers. Epigenetics Chromatin 2018; 11:68. [PMID: 30445992 PMCID: PMC6238281 DOI: 10.1186/s13072-018-0237-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 10/26/2018] [Indexed: 08/30/2023] Open
Abstract
BACKGROUND The centromere is a specialized chromosomal locus that forms the basis for the assembly of a multi-protein complex, the kinetochore and ensures faithful chromosome segregation during every cell division. The repetitive nature of the underlying centromeric sequence represents a major obstacle for high-resolution mapping of protein binding using methods that rely on annotated genomes. Here, we present a novel microscopy-based approach called "APEX-chromatin fibers" for localizing protein binding over the repetitive centromeric sequences at kilobase resolution. RESULTS By fusing centromere factors of interest to ascorbate peroxidase, we were able to label their binding profiles on extended chromatin fibers with biotin marks. We applied APEX-chromatin fibers to at least one member of each CCAN complex, most of which show a localization pattern different from CENP-A but within the CENP-A delineated centromeric domain. Interestingly, we describe here a novel characteristic of CENP-I and CENP-B that display extended localization beyond the CENP-A boundaries. CONCLUSIONS Our approach was successfully applied for mapping protein association over centromeric chromatin, revealing previously undescribed localization patterns. In this study, we focused on centromeric factors, but we believe that this approach could be useful for mapping protein binding patterns in other repetitive regions.
Collapse
Affiliation(s)
- Eftychia Kyriacou
- Max-Planck Institute of Immunobiology and Epigenetics, Freiburg im Breisgau, Germany.,Faculty of Biology, Albert-Ludwigs Universität Freiburg, Freiburg im Breisgau, Germany.,Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK
| | - Patrick Heun
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK.
| |
Collapse
|
46
|
Mann BJ, Wadsworth P. Distribution of Eg5 and TPX2 in mitosis: Insight from CRISPR tagged cells. Cytoskeleton (Hoboken) 2018; 75:508-521. [DOI: 10.1002/cm.21486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/11/2018] [Accepted: 07/30/2018] [Indexed: 11/07/2022]
Affiliation(s)
- B. J. Mann
- Department of Biology, Program in Molecular and Cellular Biology University of Massachusetts Amherst Massachusetts
| | - P. Wadsworth
- Department of Biology, Program in Molecular and Cellular Biology University of Massachusetts Amherst Massachusetts
| |
Collapse
|
47
|
Llauró A, Hayashi H, Bailey ME, Wilson A, Ludzia P, Asbury CL, Akiyoshi B. The kinetoplastid kinetochore protein KKT4 is an unconventional microtubule tip-coupling protein. J Cell Biol 2018; 217:3886-3900. [PMID: 30209069 PMCID: PMC6219724 DOI: 10.1083/jcb.201711181] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 07/23/2018] [Accepted: 08/24/2018] [Indexed: 01/08/2023] Open
Abstract
The evolutionarily divergent class of kinetoplastid organisms has a set of unconventional kinetochore proteins that drive chromosome segregation, but it is unclear which components interact with spindle microtubules. Llauró et al. now identify KKT4 as the first microtubule-binding kinetochore protein in Trypanosoma brucei, a major human pathogenic parasite. Kinetochores are multiprotein machines that drive chromosome segregation by maintaining persistent, load-bearing linkages between chromosomes and dynamic microtubule tips. Kinetochores in commonly studied eukaryotes bind microtubules through widely conserved components like the Ndc80 complex. However, in evolutionarily divergent kinetoplastid species such as Trypanosoma brucei, which causes sleeping sickness, the kinetochores assemble from a unique set of proteins lacking homology to any known microtubule-binding domains. Here, we show that the T. brucei kinetochore protein KKT4 binds directly to microtubules and maintains load-bearing attachments to both growing and shortening microtubule tips. The protein localizes both to kinetochores and to spindle microtubules in vivo, and its depletion causes defects in chromosome segregation. We define a microtubule-binding domain within KKT4 and identify several charged residues important for its microtubule-binding activity. Thus, despite its lack of significant similarity to other known microtubule-binding proteins, KKT4 has key functions required for driving chromosome segregation. We propose that it represents a primary element of the kinetochore–microtubule interface in kinetoplastids.
Collapse
Affiliation(s)
- Aida Llauró
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Hanako Hayashi
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Megan E Bailey
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Alex Wilson
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Patryk Ludzia
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Charles L Asbury
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Bungo Akiyoshi
- Department of Biochemistry, University of Oxford, Oxford, UK
| |
Collapse
|
48
|
Loss of Kif18A Results in Spindle Assembly Checkpoint Activation at Microtubule-Attached Kinetochores. Curr Biol 2018; 28:2685-2696.e4. [DOI: 10.1016/j.cub.2018.06.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 05/21/2018] [Accepted: 06/13/2018] [Indexed: 11/18/2022]
|
49
|
Suzuki A, Gupta A, Long SK, Evans R, Badger BL, Salmon ED, Biggins S, Bloom K. A Kinesin-5, Cin8, Recruits Protein Phosphatase 1 to Kinetochores and Regulates Chromosome Segregation. Curr Biol 2018; 28:2697-2704.e3. [PMID: 30174190 DOI: 10.1016/j.cub.2018.08.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 08/02/2018] [Accepted: 08/16/2018] [Indexed: 01/03/2023]
Abstract
Kinesin-5 is a highly conserved homo-tetrameric protein complex responsible for crosslinking microtubules and pushing spindle poles apart. The budding yeast Kinesin-5, Cin8, is highly concentrated at kinetochores in mitosis before anaphase, but its functions there are largely unsolved. Here, we show that Cin8 localizes to kinetochores in a cell-cycle-dependent manner and concentrates near the microtubule binding domains of Ndc80 at metaphase. Cin8's kinetochore localization depends on the Ndc80 complex, kinetochore microtubules, and the Dam1 complex. Consistent with its kinetochore localization, a Cin8 deletion induces a loss of tension at the Ndc80 microtubule binding domains and a major delay in mitotic progression. Cin8 associates with Protein Phosphatase 1 (PP1), and mutants that inhibit its PP1 binding also induce a loss of tension at the Ndc80 microtubule binding domains and delay mitotic progression. Taken together, our results suggest that Cin8-PP1 plays a critical role at kinetochores to promote accurate chromosome segregation by controlling Ndc80 attachment to microtubules.
Collapse
Affiliation(s)
- Aussie Suzuki
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; McArdle Laboratory for Cancer Research, Department of Oncology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53705, USA.
| | - Amitabha Gupta
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Sarah K Long
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Rena Evans
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Benjamin L Badger
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Edward D Salmon
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
| | - Kerry Bloom
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| |
Collapse
|
50
|
Joglekar AP, Kukreja AA. How Kinetochore Architecture Shapes the Mechanisms of Its Function. Curr Biol 2018; 27:R816-R824. [PMID: 28829971 DOI: 10.1016/j.cub.2017.06.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The eukaryotic kinetochore is a sophisticated multi-protein machine that segregates chromosomes during cell division. To ensure accurate chromosome segregation, it performs three major functions using disparate molecular mechanisms. It operates a mechanosensitive signaling cascade known as the spindle assembly checkpoint (SAC) to detect and signal the lack of attachment to spindle microtubules, and delay anaphase onset in response. In addition, after attaching to spindle microtubules, the kinetochore generates the force necessary to move chromosomes. Finally, if the two sister kinetochores on a chromosome are both attached to microtubules emanating from the same spindle pole, they activate another mechanosensitive mechanism to correct the monopolar attachments. All three of these functions maintain genome stability during cell division. The outlines of the biochemical activities responsible for these functions are now available. How the kinetochore integrates the underlying molecular mechanisms is still being elucidated. In this Review, we discuss how the nanoscale protein organization in the kinetochore, which we refer to as kinetochore 'architecture', organizes its biochemical activities to facilitate the realization and integration of emergent mechanisms underlying its three major functions. For this discussion, we will use the relatively simple budding yeast kinetochore as a model, and extrapolate insights gained from this model to elucidate functional roles of the architecture of the much more complex human kinetochore.
Collapse
Affiliation(s)
- Ajit P Joglekar
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI, USA; Department of Biophysics, University of Michigan, Ann Arbor, MI, USA.
| | | |
Collapse
|