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Kixmoeller K, Chang YW, Black BE. Centromeric chromatin clearings demarcate the site of kinetochore formation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.26.591177. [PMID: 38712116 PMCID: PMC11071481 DOI: 10.1101/2024.04.26.591177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
The centromere is the chromosomal locus that recruits the kinetochore, directing faithful propagation of the genome during cell division. The kinetochore has been interrogated by electron microscopy since the middle of the last century, but with methodologies that compromised fine structure. Using cryo-ET on human mitotic chromosomes, we reveal a distinctive architecture at the centromere: clustered 20-25 nm nucleosome-associated complexes within chromatin clearings that delineate them from surrounding chromatin. Centromere components CENP-C and CENP-N are each required for the integrity of the complexes, while CENP-C is also required to maintain the chromatin clearing. We further visualize the scaffold of the fibrous corona, a structure amplified at unattached kinetochores, revealing crescent-shaped parallel arrays of fibrils that extend >1 μm. Thus, we reveal how the organization of centromeric chromatin creates a clearing at the site of kinetochore formation as well as the nature of kinetochore amplification mediated by corona fibrils.
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Affiliation(s)
- Kathryn Kixmoeller
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Biochemistry Biophysics Chemical Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - Yi-Wei Chang
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Biochemistry Biophysics Chemical Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - Ben E. Black
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Biochemistry Biophysics Chemical Biology Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, PA, USA
- Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, PA, USA
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2
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Gambogi CW, Birchak GJ, Mer E, Brown DM, Yankson G, Kixmoeller K, Gavade JN, Espinoza JL, Kashyap P, Dupont CL, Logsdon GA, Heun P, Glass JI, Black BE. Efficient formation of single-copy human artificial chromosomes. Science 2024; 383:1344-1349. [PMID: 38513017 PMCID: PMC11059994 DOI: 10.1126/science.adj3566] [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: 06/21/2023] [Accepted: 01/23/2024] [Indexed: 03/23/2024]
Abstract
Large DNA assembly methodologies underlie milestone achievements in synthetic prokaryotic and budding yeast chromosomes. While budding yeast control chromosome inheritance through ~125-base pair DNA sequence-defined centromeres, mammals and many other eukaryotes use large, epigenetic centromeres. Harnessing centromere epigenetics permits human artificial chromosome (HAC) formation but is not sufficient to avoid rampant multimerization of the initial DNA molecule upon introduction to cells. We describe an approach that efficiently forms single-copy HACs. It employs a ~750-kilobase construct that is sufficiently large to house the distinct chromatin types present at the inner and outer centromere, obviating the need to multimerize. Delivery to mammalian cells is streamlined by employing yeast spheroplast fusion. These developments permit faithful chromosome engineering in the context of metazoan cells.
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Affiliation(s)
- Craig W. Gambogi
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | - Gabriel J. Birchak
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Graduate Program in Cell and Molecular Biology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | - Elie Mer
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | | | - George Yankson
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Kathryn Kixmoeller
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | - Janardan N. Gavade
- Department of Biochemistry and Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | | | - Prakriti Kashyap
- Department of Biochemistry and Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | | | - Glennis A. Logsdon
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
| | - Patrick Heun
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | | | - Ben E. Black
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute
- Graduate Program in Cell and Molecular Biology Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
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3
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Palao L, Murakami K, Chang YW. Combining per-particle cryo-ET and cryo-EM single particle analysis to elucidate heterogeneous DNA-protein organization. Curr Opin Struct Biol 2024; 84:102765. [PMID: 38181688 PMCID: PMC10922635 DOI: 10.1016/j.sbi.2023.102765] [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: 10/01/2023] [Revised: 12/06/2023] [Accepted: 12/11/2023] [Indexed: 01/07/2024]
Abstract
Cryo-electron microscopy single particle analysis (cryo-EM SPA) and cryo-electron tomography (cryo-ET) have historically been employed as distinct approaches for investigating molecular structures of disparate sample types, focusing on highly purified biological macromolecules and in situ cellular contexts, respectively. However, these techniques offer inherently complementary structural insights that, when combined, provide a more comprehensive understanding of complex biological systems. For example, if both techniques are applied to the same purified biological macromolecules, cryo-ET has the ability to resolve highly flexible yet strong signal features on an individual target molecule which will not be preserved in the high-resolution cryo-EM SPA results. In this review, we highlight recent achievements utilizing such applications to unveil new insights into the chromatin assembly and activities of DNA-protein assemblies. This convergence of cryo-EM SPA and cryo-ET holds great promise for elucidating new structural aspects of these essential molecular processes.
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Affiliation(s)
- Leon Palao
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA
| | - Kenji Murakami
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA; Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
| | - Yi-Wei Chang
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, PA, USA; Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, PA, USA; Institute of Structural Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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4
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Nagpal H, Ali-Ahmad A, Hirano Y, Cai W, Halic M, Fukagawa T, Sekulić N, Fierz B. CENP-A and CENP-B collaborate to create an open centromeric chromatin state. Nat Commun 2023; 14:8227. [PMID: 38086807 PMCID: PMC10716449 DOI: 10.1038/s41467-023-43739-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2022] [Accepted: 11/17/2023] [Indexed: 12/18/2023] Open
Abstract
Centromeres are epigenetically defined via the presence of the histone H3 variant CENP-A. Contacting CENP-A nucleosomes, the constitutive centromere associated network (CCAN) and the kinetochore assemble, connecting the centromere to spindle microtubules during cell division. The DNA-binding centromeric protein CENP-B is involved in maintaining centromere stability and, together with CENP-A, shapes the centromeric chromatin state. The nanoscale organization of centromeric chromatin is not well understood. Here, we use single-molecule fluorescence and cryoelectron microscopy (cryoEM) to show that CENP-A incorporation establishes a dynamic and open chromatin state. The increased dynamics of CENP-A chromatin create an opening for CENP-B DNA access. In turn, bound CENP-B further opens the chromatin fiber structure and induces nucleosomal DNA unwrapping. Finally, removal of CENP-A increases CENP-B mobility in cells. Together, our studies show that the two centromere-specific proteins collaborate to reshape chromatin structure, enabling the binding of centromeric factors and establishing a centromeric chromatin state.
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Affiliation(s)
- Harsh Nagpal
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015, Lausanne, Switzerland
| | - Ahmad Ali-Ahmad
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Faculty of Medicine, University of Oslo, Oslo, 0318, Norway
| | - Yasuhiro Hirano
- Graduate School of Frontier Biosciences, Osaka University, Suita, 565-0871, Japan
| | - Wei Cai
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015, Lausanne, Switzerland
| | - Mario Halic
- Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, 38105-3678, USA
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, 565-0871, Japan
| | - Nikolina Sekulić
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Faculty of Medicine, University of Oslo, Oslo, 0318, Norway.
- Department of Chemistry, University of Oslo, P.O. Box 1033, Blindern, 0315, Norway.
| | - Beat Fierz
- École Polytechnique Fédérale de Lausanne (EPFL), SB ISIC LCBM, Station 6, CH-1015, Lausanne, Switzerland.
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Ariyoshi M, Fukagawa T. An updated view of the kinetochore architecture. Trends Genet 2023; 39:941-953. [PMID: 37775394 DOI: 10.1016/j.tig.2023.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 10/01/2023]
Abstract
The kinetochore is a supramolecular complex that facilitates faithful chromosome segregation by bridging the centromere and spindle microtubules. Recent functional and structural studies on the inner kinetochore subcomplex, constitutive centromere-associated network (CCAN) have updated our understanding of kinetochore architecture. While the CCAN core establishes a stable interface with centromeric chromatin, CCAN organization is dynamically altered and coupled with cell cycle progression. Furthermore, the CCAN components, centromere protein (CENP)-C and CENP-T, mediate higher-order assembly of multiple kinetochore units on the regional centromeres of vertebrates. This review highlights new insights into kinetochore rigidity, plasticity, and clustering, which are key to understanding temporal and spatial regulatory mechanisms of chromosome segregation.
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Affiliation(s)
- Mariko Ariyoshi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan.
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6
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Gui Z, Tian Y, Yu T, Liu S, Liu C, Zhang L. Clinical implications and immune features of CENPN in breast cancer. BMC Cancer 2023; 23:851. [PMID: 37697245 PMCID: PMC10496242 DOI: 10.1186/s12885-023-11376-2] [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: 06/08/2023] [Accepted: 09/05/2023] [Indexed: 09/13/2023] Open
Abstract
BACKGROUND A number of human diseases have been associated with Centromere protein N (CENPN), but its role in breast cancer is unclear. METHODS A pan-cancer database of Genotype Tissue Expression (GTEx) and the Cancer Genome Atlas (TCGA) were used to examine the expression of CENPN. Using TCGA clinical survival data and breast cancer specimens from our center for validation, the relationship between CENPN expression, breast cancer prognosis, and clinicopathological characteristics of patients was examined. Bioinformatics was utilized to conduct an enrichment study of CENPN. Additionally, the potential of CENPN as a predictive biomarker for immunotherapy success was confirmed by analyzing the co-expression of CENPN with immune-checkpoint related genes, reviewing the TCGA database, and evaluating the correlation between CENPN expression and immune cell infiltration. Using the CCK8 test and colony formation assay, CENPN was evaluated for its ability to inhibit breast cancer cell proliferation. Transwell assays and scratch tests were used to assess the impact of CENPN on breast cancer cell migration. RESULTS CENPN is found in a wide range of tumors, including breast cancer. Additional investigation revealed that CENPN was co-expressed with the majority of immune checkpoint-related genes, had the potential to serve as a predictive biomarker for immunotherapy effectiveness, and that high CENPN expression was linked to high Tregs and low CD8 + T cells and NK cells. Breast cancer cells' malignant characteristics, such as migration and cell proliferation, were inhibited by CENPN knockdown. CONCLUSIONS According to our findings, CENPN may be an oncogene in breast cancer, as well as a new therapeutic target for immune checkpoint inhibitors.
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Affiliation(s)
- Zhengwei Gui
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China
| | - Yao Tian
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China
| | - Tianyao Yu
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China
| | - Shiyang Liu
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China
| | - Chenguang Liu
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China
| | - Lin Zhang
- Department of Thyroid and Breast Surgery, Tongji Hospital of Tongji Medical College of Huazhong, University of Science and Technology, 1095 Jiefang Avenue, Wuhan City, 430030, Hubei Province, China.
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Yatskevich S, Barford D, Muir KW. Conserved and divergent mechanisms of inner kinetochore assembly onto centromeric chromatin. Curr Opin Struct Biol 2023; 81:102638. [PMID: 37343495 DOI: 10.1016/j.sbi.2023.102638] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 05/03/2023] [Accepted: 05/23/2023] [Indexed: 06/23/2023]
Abstract
Kinetochores are large protein complexes built on centromeric chromatin that mediate chromosome segregation. The inner kinetochore, or constitutive centromere-associated network (CCAN), assembles onto centromeres defined by centromere protein A (CENP-A) nucleosomes (CENP-ANuc), and acts as a platform for the regulated assembly of the microtubule-binding outer kinetochore. Recent cryo-EM work revealed structural conservation of CCAN, from the repeating human regional centromeres to the point centromere of budding yeast. Centromere recognition is determined mainly through engagement of duplex DNA proximal to the CENP-A nucleosome by a DNA-binding CENP-LN channel located at the core of CCAN. Additional DNA interactions formed by other CCAN modules create an enclosed DNA-binding chamber. This configuration explains how kinetochores maintain their tight grip on centromeric DNA to withstand the forces of chromosome segregation. Defining the higher-order architecture of complete kinetochore assemblies with implications for understanding the 3D organisation of regional centromeres and mechanisms of kinetochore dynamics, including how kinetochores sense and respond to tension, are important future directions.
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Affiliation(s)
- Stanislau Yatskevich
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom. https://twitter.com/StanislauY
| | - David Barford
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom.
| | - Kyle W Muir
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, United Kingdom. https://twitter.com/centromuir
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8
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Gambogi CW, Mer E, Brown DM, Yankson G, Gavade JN, Logsdon GA, Heun P, Glass JI, Black BE. Efficient Formation of Single-copy Human Artificial Chromosomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.30.547284. [PMID: 37546784 PMCID: PMC10402137 DOI: 10.1101/2023.06.30.547284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Large DNA assembly methodologies underlie milestone achievements in synthetic prokaryotic and budding yeast chromosomes. While budding yeast control chromosome inheritance through ~125 bp DNA sequence-defined centromeres, mammals and many other eukaryotes use large, epigenetic centromeres. Harnessing centromere epigenetics permits human artificial chromosome (HAC) formation but is not sufficient to avoid rampant multimerization of the initial DNA molecule upon introduction to cells. Here, we describe an approach that efficiently forms single-copy HACs. It employs a ~750 kb construct that is sufficiently large to house the distinct chromatin types present at the inner and outer centromere, obviating the need to multimerize. Delivery to mammalian cells is streamlined by employing yeast spheroplast fusion. These developments permit faithful chromosome engineering in the context of metazoan cells.
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Affiliation(s)
- Craig W. Gambogi
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | - Elie Mer
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | | | - George Yankson
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Janardan N. Gavade
- Department of Biochemistry and Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | - Glennis A. Logsdon
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
| | - Patrick Heun
- Wellcome Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | | | - Ben E. Black
- Department of Biochemistry and Biophysics
- Graduate Program in Biochemistry and Molecular Biophysics
- Penn Center for Genome Integrity
- Epigenetics Institute Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104 USA
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Jiang H, Ariyoshi M, Hori T, Watanabe R, Makino F, Namba K, Fukagawa T. The cryo-EM structure of the CENP-A nucleosome in complex with ggKNL2. EMBO J 2023; 42:e111965. [PMID: 36744604 PMCID: PMC10015371 DOI: 10.15252/embj.2022111965] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 02/07/2023] Open
Abstract
Centromere protein A (CENP-A) nucleosomes containing the centromere-specific histone H3 variant CENP-A represent an epigenetic mark that specifies centromere position. The Mis18 complex is a licensing factor for new CENP-A deposition via the CENP-A chaperone, Holliday junction recognition protein (HJURP), on the centromere chromatin. Chicken KINETOCHORE NULL2 (KNL2) (ggKNL2), a Mis18 complex component, has a CENP-C-like motif, and our previous study suggested that ggKNL2 directly binds to the CENP-A nucleosome to recruit HJURP/CENP-A to the centromere. However, the molecular basis for CENP-A nucleosome recognition by ggKNL2 has remained unclear. Here, we present the cryo-EM structure of the chicken CENP-A nucleosome in complex with a ggKNL2 fragment containing the CENP-C-like motif. Chicken KNL2 distinguishes between CENP-A and histone H3 in the nucleosome using the CENP-C-like motif and its downstream region. Both the C-terminal tail and the RG-loop of CENP-A are simultaneously recognized as CENP-A characteristics. The CENP-A nucleosome-ggKNL2 interaction is thus essential for KNL2 functions. Furthermore, our structural, biochemical, and cell biology data indicate that ggKNL2 changes its binding partner at the centromere during chicken cell cycle progression.
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Affiliation(s)
- Honghui Jiang
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Mariko Ariyoshi
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Tetsuya Hori
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Reito Watanabe
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
| | - Fumiaki Makino
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
- JEOL Ltd.AkishimaJapan
| | - Keiichi Namba
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
- RIKEN Center for Biosystems Dynamics Research and SPring‐8 CenterSuitaJapan
- JEOL YOKOGUSHI Research Alliance LaboratoriesOsaka UniversitySuitaJapan
| | - Tatsuo Fukagawa
- Graduate School of Frontier BiosciencesOsaka UniversitySuitaJapan
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10
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Hinshaw SM, Quan Y, Cai J, Zhou AL, Zhou H. Multi-site phosphorylation of yeast Mif2/CENP-C promotes inner kinetochore assembly. Curr Biol 2023; 33:688-696.e6. [PMID: 36736323 PMCID: PMC9992315 DOI: 10.1016/j.cub.2023.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/28/2022] [Accepted: 01/09/2023] [Indexed: 02/05/2023]
Abstract
Kinetochores control eukaryotic chromosome segregation by connecting chromosomal centromeres to spindle microtubules. Duplication of centromeric DNA necessitates kinetochore disassembly and subsequent reassembly on nascent sisters. To search for a regulatory mechanism that controls the earliest steps of this process, we studied Mif2/CENP-C, an essential basal component of the kinetochore. We found that phosphorylation of a central region of Mif2 (Mif2-PEST) enhances inner kinetochore assembly. Eliminating Mif2-PEST phosphorylation sites progressively impairs cellular fitness. The most severe Mif2-PEST mutations are lethal in cells lacking otherwise non-essential inner kinetochore factors. These data show that multi-site phosphorylation of Mif2/CENP-C controls inner kinetochore assembly.
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Affiliation(s)
- Stephen M Hinshaw
- Stanford Cancer Institute, Stanford School of Medicine, 1291 Welch Road, Stanford, CA 94305, USA.
| | - Yun Quan
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Jiaxi Cai
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Ann L Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA
| | - Huilin Zhou
- Department of Cellular and Molecular Medicine, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92039, USA.
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11
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Centromere Chromatin Dynamics at a Glance. EPIGENOMES 2022; 6:epigenomes6040039. [PMID: 36412794 PMCID: PMC9680212 DOI: 10.3390/epigenomes6040039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 10/27/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
The centromere is a specialized DNA locus that ensures the faithful segregation of chromosomes during cell division. It does so by directing the assembly of an essential proteinaceous structure called the kinetochore. The centromere identity is primarily epigenetically defined by a nucleosome containing an H3 variant called CENP-A as well as by the interplay of several factors such as differential chromatin organization driven by CENP-A and H2A.Z, centromere-associated proteins, and post-translational modifications. At the centromere, CENP-A is not just a driving force for kinetochore assembly but also modifies the structural and dynamic properties of the centromeric chromatin, resulting in a distinctive chromatin organization. An additional level of regulation of the centromeric chromatin conformation is provided by post-translational modifications of the histones in the CENP-A nucleosomes. Further, H2A.Z is present in the regions flanking the centromere for heterochromatinization. In this review, we focus on the above-mentioned factors to describe how they contribute to the organization of the centromeric chromatin: CENP-A at the core centromere, post-translational modifications that decorate CENP-A, and the variant H2A.Z.
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12
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Navarro AP, Cheeseman IM. Dynamic cell cycle-dependent phosphorylation modulates CENP-L-CENP-N centromere recruitment. Mol Biol Cell 2022; 33:ar87. [PMID: 35830614 PMCID: PMC9582625 DOI: 10.1091/mbc.e22-06-0239] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The kinetochore is a macromolecular structure that is needed to ensure proper chromosome segregation during each cellular division. The kinetochore is assembled upon a platform of the 16-subunit constitutive centromere-associated network (CCAN), which is present at centromeres throughout the cell cycle. The nature and regulation of CCAN assembly, interactions, and dynamics needed to facilitate changing centromere properties and requirements remain to be fully elucidated. The CENP-LN complex is a CCAN component that displays unique cell cycle–dependent localization behavior, peaking in the S phase. Here, we demonstrate that phosphorylation of CENP-L and CENP-N controls CENP-LN complex formation and localization in a cell cycle–dependent manner. Mimicking constitutive phosphorylation of either CENP-L or CENP-N or simultaneously preventing phosphorylation of both proteins prevents CENP-LN localization and disrupts chromosome segregation. Our work suggests that cycles of phosphorylation and dephosphorylation are critical for CENP-LN complex recruitment and dynamics at kinetochores to enable cell cycle–dependent CCAN reorganization.
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Affiliation(s)
- Alexandra P Navarro
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, Cambridge, MA 02142.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142
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13
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Something's gotta give at the centromeric chromatin foundation of the kinetochore. Mol Cell 2022; 82:1976-1978. [PMID: 35659323 DOI: 10.1016/j.molcel.2022.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Structures of the reconstituted human inner kinetochore complex by Pesenti et al. (2022) and Yatskevich et al. (2022) raise the question of whether it is the CENP-A nucleosome or the CCAN complex itself that provides the foundation for kinetochore assembly.
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14
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Renaud-Pageot C, Quivy JP, Lochhead M, Almouzni G. CENP-A Regulation and Cancer. Front Cell Dev Biol 2022; 10:907120. [PMID: 35721491 PMCID: PMC9201071 DOI: 10.3389/fcell.2022.907120] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/11/2022] [Indexed: 11/13/2022] Open
Abstract
In mammals, CENP-A, a histone H3 variant found in the centromeric chromatin, is critical for faithful chromosome segregation and genome integrity maintenance through cell divisions. Specifically, it has dual functions, enabling to define epigenetically the centromere position and providing the foundation for building up the kinetochore. Regulation of its dynamics of synthesis and deposition ensures to propagate proper centromeres on each chromosome across mitosis and meiosis. However, CENP-A overexpression is a feature identified in many cancers. Importantly, high levels of CENP-A lead to its mislocalization outside the centromere. Recent studies in mammals have begun to uncover how CENP-A overexpression can affect genome integrity, reprogram cell fate and impact 3D nuclear organization in cancer. Here, we summarize the mechanisms that orchestrate CENP-A regulation. Then we review how, beyond its centromeric function, CENP-A overexpression is linked to cancer state in mammalian cells, with a focus on the perturbations that ensue at the level of chromatin organization. Finally, we review the clinical interest for CENP-A in cancer treatment.
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15
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Yatskevich S, Muir KW, Bellini D, Zhang Z, Yang J, Tischer T, Predin M, Dendooven T, McLaughlin SH, Barford D. Structure of the human inner kinetochore bound to a centromeric CENP-A nucleosome. Science 2022; 376:844-852. [PMID: 35420891 PMCID: PMC7612757 DOI: 10.1126/science.abn3810] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Kinetochores assemble onto specialized centromeric CENP-A (centromere protein A) nucleosomes (CENP-ANuc) to mediate attachments between chromosomes and the mitotic spindle. We describe cryo-electron microscopy structures of the human inner kinetochore constitutive centromere associated network (CCAN) complex bound to CENP-ANuc reconstituted onto α-satellite DNA. CCAN forms edge-on contacts with CENP-ANuc, and a linker DNA segment of the α-satellite repeat emerges from the fully wrapped end of the nucleosome to thread through the central CENP-LN channel that tightly grips the DNA. The CENP-TWSX histone-fold module further augments DNA binding and partially wraps the linker DNA in a manner reminiscent of canonical nucleosomes. Our study suggests that the topological entrapment of the linker DNA by CCAN provides a robust mechanism by which kinetochores withstand both pushing and pulling forces exerted by the mitotic spindle.
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Affiliation(s)
- Stanislau Yatskevich
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Kyle W. Muir
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Dom Bellini
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Ziguo Zhang
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Jing Yang
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Thomas Tischer
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Masa Predin
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Tom Dendooven
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | | | - David Barford
- MRC Laboratory of Molecular Biology; Francis Crick Avenue, Cambridge, CB2 0QH, UK
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16
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Pesenti ME, Raisch T, Conti D, Walstein K, Hoffmann I, Vogt D, Prumbaum D, Vetter IR, Raunser S, Musacchio A. Structure of the human inner kinetochore CCAN complex and its significance for human centromere organization. Mol Cell 2022; 82:2113-2131.e8. [PMID: 35525244 PMCID: PMC9235857 DOI: 10.1016/j.molcel.2022.04.027] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 04/01/2022] [Accepted: 04/22/2022] [Indexed: 11/24/2022]
Abstract
Centromeres are specialized chromosome loci that seed the kinetochore, a large protein complex that effects chromosome segregation. A 16-subunit complex, the constitutive centromere associated network (CCAN), connects between the specialized centromeric chromatin, marked by the histone H3 variant CENP-A, and the spindle-binding moiety of the kinetochore. Here, we report a cryo-electron microscopy structure of human CCAN. We highlight unique features such as the pseudo GTPase CENP-M and report how a crucial CENP-C motif binds the CENP-LN complex. The CCAN structure has implications for the mechanism of specific recognition of the CENP-A nucleosome. A model consistent with our structure depicts the CENP-C-bound nucleosome as connected to the CCAN through extended, flexible regions of CENP-C. An alternative model identifies both CENP-C and CENP-N as specificity determinants but requires CENP-N to bind CENP-A in a mode distinct from the classical nucleosome octamer.
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Affiliation(s)
- Marion E Pesenti
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Tobias Raisch
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Duccio Conti
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Kai Walstein
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Ingrid Hoffmann
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Dorothee Vogt
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Daniel Prumbaum
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Ingrid R Vetter
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Stefan Raunser
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany.
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max-Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstrasse, 45141 Essen, Germany.
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17
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Zhou K, Gebala M, Woods D, Sundararajan K, Edwards G, Krzizike D, Wereszczynski J, Straight AF, Luger K. CENP-N promotes the compaction of centromeric chromatin. Nat Struct Mol Biol 2022; 29:403-413. [PMID: 35422519 PMCID: PMC9010303 DOI: 10.1038/s41594-022-00758-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 03/08/2022] [Indexed: 12/14/2022]
Abstract
The histone variant CENP-A is the epigenetic determinant for the centromere, where it is interspersed with canonical H3 to form a specialized chromatin structure that nucleates the kinetochore. How nucleosomes at the centromere arrange into higher order structures is unknown. Here we demonstrate that the human CENP-A-interacting protein CENP-N promotes the stacking of CENP-A-containing mononucleosomes and nucleosomal arrays through a previously undefined interaction between the α6 helix of CENP-N with the DNA of a neighboring nucleosome. We describe the cryo-EM structures and biophysical characterization of such CENP-N-mediated nucleosome stacks and nucleosomal arrays and demonstrate that this interaction is responsible for the formation of densely packed chromatin at the centromere in the cell. Our results provide first evidence that CENP-A, together with CENP-N, promotes specific chromatin higher order structure at the centromere.
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Affiliation(s)
- Keda Zhou
- Department of Biochemistry, University of Colorado at Boulder, Boulder, CO, USA
| | - Magdalena Gebala
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | - Dustin Woods
- Department of Chemistry and the Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, USA
| | | | - Garrett Edwards
- Department of Biochemistry, University of Colorado at Boulder, Boulder, CO, USA
| | - Dan Krzizike
- Department of Biochemistry, University of Colorado at Boulder, Boulder, CO, USA
| | - Jeff Wereszczynski
- Department of Physics and the Center for Molecular Study of Condensed Soft Matter, Illinois Institute of Technology, Chicago, IL, USA
| | - Aaron F Straight
- Department of Biochemistry, Stanford University, Stanford, CA, USA.
| | - Karolin Luger
- Department of Biochemistry, University of Colorado at Boulder, Boulder, CO, USA.
- Howard Hughes Medical Institute, University of Colorado at Boulder, Boulder, CO, USA.
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18
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Bolanos-Garcia VM. On the Regulation of Mitosis by the Kinetochore, a Macromolecular Complex and Organising Hub of Eukaryotic Organisms. Subcell Biochem 2022; 99:235-267. [PMID: 36151378 DOI: 10.1007/978-3-031-00793-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The kinetochore is the multiprotein complex of eukaryotic organisms that is assembled on mitotic or meiotic centromeres to connect centromeric DNA with microtubules. Its function involves the coordinated action of more than 100 different proteins. The kinetochore acts as an organiser hub that establishes physical connections with microtubules and centromere-associated proteins and recruits central protein components of the spindle assembly checkpoint (SAC), an evolutionarily conserved surveillance mechanism of eukaryotic organisms that detects unattached kinetochores and destabilises incorrect kinetochore-microtubule attachments. The molecular communication between the kinetochore and the SAC is highly dynamic and tightly regulated to ensure that cells can progress towards anaphase until each chromosome is properly bi-oriented on the mitotic spindle. This is achieved through an interplay of highly cooperative interactions and concerted phosphorylation/dephosphorylation events that are organised in time and space.This contribution discusses our current understanding of the function, structure and regulation of the kinetochore, in particular, how its communication with the SAC results in the amplification of specific signals to exquisitely control the eukaryotic cell cycle. This contribution also addresses recent advances in machine learning approaches, cell imaging and proteomics techniques that have enhanced our understanding of the molecular mechanisms that ensure the high fidelity and timely segregation of the genetic material every time a cell divides as well as the current challenges in the study of this fascinating molecular machine.
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Affiliation(s)
- Victor M Bolanos-Garcia
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK.
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19
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Salinas-Luypaert C, Allu PK, Logsdon GA, Dawicki-McKenna JM, Gambogi CW, Fachinetti D, Black BE. Gene replacement strategies validate the use of functional tags on centromeric chromatin and invalidate an essential role for CENP-A K124ub. Cell Rep 2021; 37:109924. [PMID: 34731637 PMCID: PMC8643106 DOI: 10.1016/j.celrep.2021.109924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 08/31/2021] [Accepted: 10/12/2021] [Indexed: 12/17/2022] Open
Abstract
Functional tags are ubiquitous in cell biology, and for studies of one chromosomal locus, the centromere, tags have been remarkably useful. The centromere directs chromosome inheritance at cell division. The location of the centromere is defined by a histone H3 variant, CENP-A. The regulation of the chromatin assembly pathway essential for centromere inheritance and function includes posttranslational modification (PTM) of key components, including CENP-A itself. Others have recently called into question the use of functional tags, with the claim that at least two widely used tags obscured the essentiality of one particular PTM, CENP-AK124 ubiquitination (ub). Here, we employ three independent gene replacement strategies that eliminate large, lysine-containing tags to interrogate these claims. Using these approaches, we find no evidence to support an essential function of CENP-AK124ub. Our general methodology will be useful to validate discoveries permitted by powerful functional tagging schemes at the centromere and other cellular locations. Using three gene replacement strategies, Salinas-Luypaert et al. demonstrate that CENP-AK124ub is not essential for CENP-A function at centromeres. Thus, functional tags do not mask the role of K124 when it is mutated. These strategies can be employed to interrogate posttranslational modifications at the centromere and other cellular locations.
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Affiliation(s)
| | - Praveen Kumar Allu
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Glennis A Logsdon
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA 98195, USA
| | - Jennine M Dawicki-McKenna
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Craig W Gambogi
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Program in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Daniele Fachinetti
- Institut Curie, PSL University, CNRS, UMR 144, 26 rue d'Ulm, 75005, Paris, France.
| | - Ben E Black
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Graduate Program in Biochemistry and Molecular Biophysics, University of Pennsylvania, Philadelphia, PA 19104, USA.
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20
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Kumon T, Ma J, Akins RB, Stefanik D, Nordgren CE, Kim J, Levine MT, Lampson MA. Parallel pathways for recruiting effector proteins determine centromere drive and suppression. Cell 2021; 184:4904-4918.e11. [PMID: 34433012 PMCID: PMC8448984 DOI: 10.1016/j.cell.2021.07.037] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 06/07/2021] [Accepted: 07/29/2021] [Indexed: 12/19/2022]
Abstract
Selfish centromere DNA sequences bias their transmission to the egg in female meiosis. Evolutionary theory suggests that centromere proteins evolve to suppress costs of this "centromere drive." In hybrid mouse models with genetically different maternal and paternal centromeres, selfish centromere DNA exploits a kinetochore pathway to recruit microtubule-destabilizing proteins that act as drive effectors. We show that such functional differences are suppressed by a parallel pathway for effector recruitment by heterochromatin, which is similar between centromeres in this system. Disrupting the kinetochore pathway with a divergent allele of CENP-C reduces functional differences between centromeres, whereas disrupting heterochromatin by CENP-B deletion amplifies the differences. Molecular evolution analyses using Murinae genomes identify adaptive evolution in proteins in both pathways. We propose that centromere proteins have recurrently evolved to minimize the kinetochore pathway, which is exploited by selfish DNA, relative to the heterochromatin pathway that equalizes centromeres, while maintaining essential functions.
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Affiliation(s)
- Tomohiro Kumon
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jun Ma
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - R Brian Akins
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Derek Stefanik
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - C Erik Nordgren
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Junhyong Kim
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mia T Levine
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA; Epigenetics Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael A Lampson
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA.
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21
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McGinty RK, Tan S. Principles of nucleosome recognition by chromatin factors and enzymes. Curr Opin Struct Biol 2021; 71:16-26. [PMID: 34198054 DOI: 10.1016/j.sbi.2021.05.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/10/2021] [Accepted: 05/13/2021] [Indexed: 12/20/2022]
Abstract
The recent torrent of structures of chromatin complexes determined by cryoelectron microscopy provides an opportunity to discern general principles for how chromatin factors and enzymes interact with their nucleosome substrate. We find that many chromatin proteins use a strikingly similar arginine anchor and variant arginine interactions to bind to the nucleosome acidic patch. We also observe that many chromatin proteins target the H3 and H2B histone fold α1-loop1 elbows and the H2B C-terminal helix on the nucleosomal histone face. These interactions with the histones can be complemented with interactions with and distortions of nucleosomal DNA.
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Affiliation(s)
- Robert K McGinty
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Song Tan
- Department of Biochemistry and Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802, USA.
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22
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Tarasovetc EV, Allu PK, Wimbish RT, DeLuca JG, Cheeseman IM, Black BE, Grishchuk EL. Permitted and restricted steps of human kinetochore assembly in mitotic cell extracts. Mol Biol Cell 2021; 32:1241-1255. [PMID: 33956511 PMCID: PMC8351545 DOI: 10.1091/mbc.e20-07-0461] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 04/13/2021] [Accepted: 04/26/2021] [Indexed: 12/24/2022] Open
Abstract
Mitotic kinetochores assemble via the hierarchical recruitment of numerous cytosolic components to the centromere region of each chromosome. However, how these orderly and localized interactions are achieved without spurious macromolecular assemblies forming from soluble kinetochore components in the cell cytosol remains poorly understood. We developed assembly assays to monitor the recruitment of green fluorescent protein-tagged recombinant proteins and native proteins from human cell extracts to inner kinetochore components immobilized on microbeads. In contrast to prior work in yeast and Xenopus egg extracts, we find that human mitotic cell extracts fail to support de novo assembly of microtubule-binding subcomplexes. A subset of interactions, such as those between CENP-A-containing nucleosomes and CENP-C, are permissive under these conditions. However, the subsequent phospho-dependent binding of the Mis12 complex is less efficient, whereas recruitment of the Ndc80 complex is blocked, leading to weak microtubule-binding activity of assembled particles. Using molecular variants of the Ndc80 complex, we show that auto-inhibition of native Ndc80 complex restricts its ability to bind to the CENP-T/W complex, whereas inhibition of the Ndc80 microtubule binding is driven by a different mechanism. Together, our work reveals regulatory mechanisms that guard against the spurious formation of cytosolic microtubule-binding kinetochore particles.
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Affiliation(s)
- Ekaterina V. Tarasovetc
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Praveen Kumar Allu
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Robert T. Wimbish
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523
| | - Jennifer G. DeLuca
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523
| | | | - Ben E. Black
- Department of Biochemistry and Biophysics, Penn Center for Genome Integrity, Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
| | - Ekaterina L. Grishchuk
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104
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23
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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.
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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
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24
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Ho CH, Takizawa Y, Kobayashi W, Arimura Y, Kimura H, Kurumizaka H. Structural basis of nucleosomal histone H4 lysine 20 methylation by SET8 methyltransferase. Life Sci Alliance 2021; 4:e202000919. [PMID: 33574035 PMCID: PMC7893823 DOI: 10.26508/lsa.202000919] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 01/07/2021] [Accepted: 01/14/2021] [Indexed: 11/26/2022] Open
Abstract
SET8 is solely responsible for histone H4 lysine-20 (H4K20) monomethylation, which preferentially occurs in nucleosomal H4. However, the underlying mechanism by which SET8 specifically promotes the H4K20 monomethylation in the nucleosome has not been elucidated. Here, we report the cryo-EM structures of the human SET8-nucleosome complexes with histone H3 and the centromeric H3 variant, CENP-A. Surprisingly, we found that the overall cryo-EM structures of the SET8-nucleosome complexes are substantially different from the previous crystal structure models. In the complexes with H3 and CENP-A nucleosomes, SET8 specifically binds the nucleosomal acidic patch via an arginine anchor, composed of the Arg188 and Arg192 residues. Mutational analyses revealed that the interaction between the SET8 arginine anchor and the nucleosomal acidic patch plays an essential role in the H4K20 monomethylation activity. These results provide the groundwork for understanding the mechanism by which SET8 specifically accomplishes the H4K20 monomethylation in the nucleosome.
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Affiliation(s)
- Cheng-Han Ho
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yoshimasa Takizawa
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Wataru Kobayashi
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
| | - Yasuhiro Arimura
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Kimura
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Yokohama, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
- Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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25
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Cell-cycle phospho-regulation of the kinetochore. Curr Genet 2021; 67:177-193. [PMID: 33221975 DOI: 10.1007/s00294-020-01127-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 10/27/2020] [Accepted: 10/29/2020] [Indexed: 02/07/2023]
Abstract
The kinetochore is a mega-dalton protein assembly that forms within centromeric regions of chromosomes and directs their segregation during cell division. Here we review cell cycle-mediated phosphorylation events at the kinetochore, with a focus on the budding yeast Saccharomyces cerevisiae and the insight gained from forced associations of kinases and phosphatases. The point centromeres found in the budding yeast S. cerevisiae are one of the simplest such structures found in eukaryotes. The S. cerevisiae kinetochore comprises a single nucleosome, containing a centromere-specific H3 variant Cse4CENP-A, bound to a set of kinetochore proteins that connect to a single microtubule. Despite the simplicity of the budding yeast kinetochore, the proteins are mostly homologous with their mammalian counterparts. In some cases, human proteins can complement their yeast orthologs. Like its mammalian equivalent, the regulation of the budding yeast kinetochore is complex: integrating signals from the cell cycle, checkpoints, error correction, and stress pathways. The regulatory signals from these diverse pathways are integrated at the kinetochore by post-translational modifications, notably phosphorylation and dephosphorylation, to control chromosome segregation. Here we highlight the complex interplay between the activity of the different cell-cycle kinases and phosphatases at the kinetochore, emphasizing how much more we have to understand this essential structure.
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26
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Navarro AP, Cheeseman IM. Kinetochore assembly throughout the cell cycle. Semin Cell Dev Biol 2021; 117:62-74. [PMID: 33753005 DOI: 10.1016/j.semcdb.2021.03.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/29/2022]
Abstract
The kinetochore plays an essential role in facilitating chromosome segregation during cell division. This massive protein complex assembles onto the centromere of chromosomes and enables their attachment to spindle microtubules during mitosis. The kinetochore also functions as a signaling hub to regulate cell cycle progression, and is crucial to ensuring the fidelity of chromosome segregation. Despite the fact that kinetochores are large and robust molecular assemblies, they are also highly dynamic structures that undergo structural and organizational changes throughout the cell cycle. This review will highlight our current understanding of kinetochore structure and function, focusing on the dynamic processes that underlie kinetochore assembly.
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Affiliation(s)
- Alexandra P Navarro
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Iain M Cheeseman
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
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27
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Structural and dynamic mechanisms of CBF3-guided centromeric nucleosome formation. Nat Commun 2021; 12:1763. [PMID: 33741944 PMCID: PMC7979930 DOI: 10.1038/s41467-021-21985-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 02/22/2021] [Indexed: 11/08/2022] Open
Abstract
Accurate chromosome segregation relies on the specific centromeric nucleosome-kinetochore interface. In budding yeast, the centromere CBF3 complex guides the deposition of CENP-A, an H3 variant, to form the centromeric nucleosome in a DNA sequence-dependent manner. Here, we determine the structures of the centromeric nucleosome containing the native CEN3 DNA and the CBF3core bound to the canonical nucleosome containing an engineered CEN3 DNA. The centromeric nucleosome core structure contains 115 base pair DNA including a CCG motif. The CBF3core specifically recognizes the nucleosomal CCG motif through the Gal4 domain while allosterically altering the DNA conformation. Cryo-EM, modeling, and mutational studies reveal that the CBF3core forms dynamic interactions with core histones H2B and CENP-A in the CEN3 nucleosome. Our results provide insights into the structure of the budding yeast centromeric nucleosome and the mechanism of its assembly, which have implications for analogous processes of human centromeric nucleosome formation.
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28
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Nagpal H, Fierz B. The Elusive Structure of Centro-Chromatin: Molecular Order or Dynamic Heterogenetity? J Mol Biol 2021; 433:166676. [PMID: 33065112 DOI: 10.1016/j.jmb.2020.10.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/07/2020] [Accepted: 10/08/2020] [Indexed: 01/09/2023]
Abstract
The centromere is an essential chromatin domain required for kinetochore recruitment and chromosome segregation in eukaryotes. To perform this role, centro-chromatin adopts a unique structure that provides access to kinetochore proteins and maintains stability under tension during mitosis. This is achieved by the presence of nucleosomes containing the H3 variant CENP-A, which also acts as the epigenetic mark defining the centromere. In this review, we discuss the role of CENP-A on the structure and dynamics of centromeric chromatin. We further discuss the impact of the CENP-A binding proteins CENP-C, CENP-N, and CENP-B on modulating centro-chromatin structure. Based on these findings we provide an overview of the higher order structure of the centromere.
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Affiliation(s)
- Harsh Nagpal
- Laboratory of Biophysical Chemistry of Macromolecules, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
| | - Beat Fierz
- Laboratory of Biophysical Chemistry of Macromolecules, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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29
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CENP-A nucleosome-a chromatin-embedded pedestal for the centromere: lessons learned from structural biology. Essays Biochem 2021; 64:205-221. [PMID: 32720682 PMCID: PMC7475651 DOI: 10.1042/ebc20190074] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 06/16/2020] [Accepted: 06/19/2020] [Indexed: 11/17/2022]
Abstract
The centromere is a chromosome locus that directs equal segregation of chromosomes during cell division. A nucleosome containing the histone H3 variant CENP-A epigenetically defines the centromere. Here, we summarize findings from recent structural biology studies, including several CryoEM structures, that contributed to elucidate specific features of the CENP-A nucleosome and molecular determinants of its interactions with CENP-C and CENP-N, the only two centromere proteins that directly bind to it. Based on those findings, we propose a role of the CENP-A nucleosome in the organization of centromeric chromatin beyond binding centromeric proteins.
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30
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Ariyoshi M, Makino F, Watanabe R, Nakagawa R, Kato T, Namba K, Arimura Y, Fujita R, Kurumizaka H, Okumura EI, Hara M, Fukagawa T. Cryo-EM structure of the CENP-A nucleosome in complex with phosphorylated CENP-C. EMBO J 2021; 40:e105671. [PMID: 33463726 DOI: 10.15252/embj.2020105671] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 12/18/2022] Open
Abstract
The CENP-A nucleosome is a key structure for kinetochore assembly. Once the CENP-A nucleosome is established in the centromere, additional proteins recognize the CENP-A nucleosome to form a kinetochore. CENP-C and CENP-N are CENP-A binding proteins. We previously demonstrated that vertebrate CENP-C binding to the CENP-A nucleosome is regulated by CDK1-mediated CENP-C phosphorylation. However, it is still unknown how the phosphorylation of CENP-C regulates its binding to CENP-A. It is also not completely understood how and whether CENP-C and CENP-N act together on the CENP-A nucleosome. Here, using cryo-electron microscopy (cryo-EM) in combination with biochemical approaches, we reveal a stable CENP-A nucleosome-binding mode of CENP-C through unique regions. The chicken CENP-C structure bound to the CENP-A nucleosome is stabilized by an intramolecular link through the phosphorylated CENP-C residue. The stable CENP-A-CENP-C complex excludes CENP-N from the CENP-A nucleosome. These findings provide mechanistic insights into the dynamic kinetochore assembly regulated by CDK1-mediated CENP-C phosphorylation.
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Affiliation(s)
- Mariko Ariyoshi
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
| | - Fumiaki Makino
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan.,JEOL Ltd., Akishima, Tokyo, Japan
| | - Reito Watanabe
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
| | - Reiko Nakagawa
- Laboratory for Phyloinformatics, RIKEN Center for Biosystems Dynamics Research (BDR), Kobe, Hyogo, Japan
| | - Takayuki Kato
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan.,Institute of Protein Research, Osaka University, Suita, Osaka, Japan
| | - Keiichi Namba
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan.,RIKEN Center for Biosystems Dynamics Research (BDR) and SPring-8 Center, and JEOL YOKOGUSHI Research Alliance Laboratories, Osaka University, Suita, Osaka, Japan
| | - Yasuhiro Arimura
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Risa Fujita
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Hitoshi Kurumizaka
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, Japan
| | - Ei-Ichi Okumura
- Laboratory of Cell and Developmental Biology, Graduate School of Bioscience, Tokyo Institute of Technology, Yokohama, Japan
| | - Masatoshi Hara
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, Japan
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31
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Peng Y, Markov Y, Goncearenco A, Landsman D, Panchenko AR. Human Histone Interaction Networks: An Old Concept, New Trends. J Mol Biol 2020; 433:166684. [PMID: 33098859 DOI: 10.1016/j.jmb.2020.10.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/12/2020] [Accepted: 10/13/2020] [Indexed: 12/19/2022]
Abstract
To elucidate the properties of human histone interactions on the large scale, we perform a comprehensive mapping of human histone interaction networks by using data from structural, chemical cross-linking and various high-throughput studies. Histone interactomes derived from different data sources show limited overlap and complement each other. It inspires us to integrate these data into the combined histone global interaction network which includes 5308 proteins and 10,330 interactions. The analysis of topological properties of the human histone interactome reveals its scale free behavior and high modularity. Our study of histone binding interfaces uncovers a remarkably high number of residues involved in interactions between histones and non-histone proteins, 80-90% of residues in histones H3 and H4 have at least one binding partner. Two types of histone binding modes are detected: interfaces conserved in most histone variants and variant specific interfaces. Finally, different types of chromatin factors recognize histones in nucleosomes via distinct binding modes, and many of these interfaces utilize acidic patches among other sites. Interaction networks are available at https://github.com/Panchenko-Lab/Human-histone-interactome.
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Affiliation(s)
- Yunhui Peng
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD 20894, USA
| | - Yaroslav Markov
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD 20894, USA; Computational Biology and Bioinformatics, Combined Program in the Biological and Biomedical Sciences, Yale University, New Haven, CT 06520, USA
| | - Alexander Goncearenco
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD 20894, USA; VantAI, New York, NY 10003, USA
| | - David Landsman
- National Center for Biotechnology Information, National Institutes of Health, Bethesda, MD 20894, USA.
| | - Anna R Panchenko
- Department of Pathology and Molecular Medicine, School of Medicine, Queen's University, ON K7L 3N6, Canada.
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32
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Kurumizaka H, Kujirai T, Takizawa Y. Contributions of Histone Variants in Nucleosome Structure and Function. J Mol Biol 2020; 433:166678. [PMID: 33065110 DOI: 10.1016/j.jmb.2020.10.012] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 11/19/2022]
Abstract
Chromatin compacts genomic DNA in eukaryotes. The primary chromatin unit is the nucleosome core particle, composed of four pairs of the core histones, H2A, H2B, H3, and H4, and 145-147 base pairs of DNA. Since replication, recombination, repair, and transcription take place in chromatin, the structure and dynamics of the nucleosome must be versatile. These nucleosome characteristics underlie the epigenetic regulation of genomic DNA. In higher eukaryotes, many histone variants have been identified as non-allelic isoforms, which confer nucleosome diversity. In this article, we review the manifold types of nucleosomes produced by histone variants, which play important roles in the epigenetic regulation of chromatin.
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Affiliation(s)
- Hitoshi Kurumizaka
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
| | - Tomoya Kujirai
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
| | - Yoshimasa Takizawa
- Laboratory of Chromatin Structure and Function, Institute for Quantitative Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
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33
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Mitra S, Srinivasan B, Jansen LE. Stable inheritance of CENP-A chromatin: Inner strength versus dynamic control. J Cell Biol 2020; 219:e202005099. [PMID: 32931551 PMCID: PMC7659725 DOI: 10.1083/jcb.202005099] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 08/08/2020] [Accepted: 08/12/2020] [Indexed: 12/22/2022] Open
Abstract
Chromosome segregation during cell division is driven by mitotic spindle attachment to the centromere region on each chromosome. Centromeres form a protein scaffold defined by chromatin featuring CENP-A, a conserved histone H3 variant, in a manner largely independent of local DNA cis elements. CENP-A nucleosomes fulfill two essential criteria to epigenetically identify the centromere. They undergo self-templated duplication to reestablish centromeric chromatin following DNA replication. More importantly, CENP-A incorporated into centromeric chromatin is stably transmitted through consecutive cell division cycles. CENP-A nucleosomes have unique structural properties and binding partners that potentially explain their long lifetime in vivo. However, rather than a static building block, centromeric chromatin is dynamically regulated throughout the cell cycle, indicating that CENP-A stability is also controlled by external factors. We discuss recent insights and identify the outstanding questions on how dynamic control of the long-term stability of CENP-A ensures epigenetic centromere inheritance.
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Affiliation(s)
- Sreyoshi Mitra
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Bharath Srinivasan
- Mechanistic Biology and Profiling, Discovery Sciences, R&D, AstraZeneca, Cambridge, UK
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34
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Meiotic CENP-C is a shepherd: bridging the space between the centromere and the kinetochore in time and space. Essays Biochem 2020; 64:251-261. [PMID: 32794572 DOI: 10.1042/ebc20190080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/15/2020] [Accepted: 07/20/2020] [Indexed: 01/10/2023]
Abstract
While many of the proteins involved in the mitotic centromere and kinetochore are conserved in meiosis, they often gain a novel function due to the unique needs of homolog segregation during meiosis I (MI). CENP-C is a critical component of the centromere for kinetochore assembly in mitosis. Recent work, however, has highlighted the unique features of meiotic CENP-C. Centromere establishment and stability require CENP-C loading at the centromere for CENP-A function. Pre-meiotic loading of proteins necessary for homolog recombination as well as cohesion also rely on CENP-C, as do the main scaffolding components of the kinetochore. Much of this work relies on new technologies that enable in vivo analysis of meiosis like never before. Here, we strive to highlight the unique role of this highly conserved centromere protein that loads on to centromeres prior to M-phase onset, but continues to perform critical functions through chromosome segregation. CENP-C is not merely a structural link between the centromere and the kinetochore, but also a functional one joining the processes of early prophase homolog synapsis to late metaphase kinetochore assembly and signaling.
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35
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Hara M, Fukagawa T. Dynamics of kinetochore structure and its regulations during mitotic progression. Cell Mol Life Sci 2020; 77:2981-2995. [PMID: 32052088 PMCID: PMC11104943 DOI: 10.1007/s00018-020-03472-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 12/27/2019] [Accepted: 01/28/2020] [Indexed: 12/12/2022]
Abstract
Faithful chromosome segregation during mitosis in eukaryotes requires attachment of the kinetochore, a large protein complex assembled on the centromere of each chromosome, to the spindle microtubules. The kinetochore is a structural interface for the microtubule attachment and provides molecular surveillance mechanisms that monitor and ensure the precise microtubule attachment as well, including error correction and spindle assembly checkpoint. During mitotic progression, the kinetochore undergoes dynamic morphological changes that are observable through electron microscopy as well as through fluorescence microscopy. These structural changes might be associated with the kinetochore function. In this review, we summarize how the dynamics of kinetochore morphology are associated with its functions and discuss recent findings on the switching of protein interaction networks in the kinetochore during cell cycle progression.
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Affiliation(s)
- Masatoshi Hara
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan.
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36
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Mahlke MA, Nechemia-Arbely Y. Guarding the Genome: CENP-A-Chromatin in Health and Cancer. Genes (Basel) 2020; 11:genes11070810. [PMID: 32708729 PMCID: PMC7397030 DOI: 10.3390/genes11070810] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/10/2020] [Accepted: 07/15/2020] [Indexed: 02/07/2023] Open
Abstract
Faithful chromosome segregation is essential for the maintenance of genomic integrity and requires functional centromeres. Centromeres are epigenetically defined by the histone H3 variant, centromere protein A (CENP-A). Here we highlight current knowledge regarding CENP-A-containing chromatin structure, specification of centromere identity, regulation of CENP-A deposition and possible contribution to cancer formation and/or progression. CENP-A overexpression is common among many cancers and predicts poor prognosis. Overexpression of CENP-A increases rates of CENP-A deposition ectopically at sites of high histone turnover, occluding CCCTC-binding factor (CTCF) binding. Ectopic CENP-A deposition leads to mitotic defects, centromere dysfunction and chromosomal instability (CIN), a hallmark of cancer. CENP-A overexpression is often accompanied by overexpression of its chaperone Holliday Junction Recognition Protein (HJURP), leading to epigenetic addiction in which increased levels of HJURP and CENP-A become necessary to support rapidly dividing p53 deficient cancer cells. Alterations in CENP-A posttranslational modifications are also linked to chromosome segregation errors and CIN. Collectively, CENP-A is pivotal to genomic stability through centromere maintenance, perturbation of which can lead to tumorigenesis.
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Affiliation(s)
- Megan A. Mahlke
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA;
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Yael Nechemia-Arbely
- UPMC Hillman Cancer Center, Pittsburgh, PA 15213, USA;
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Correspondence: ; Tel.: +1-412-623-3228; Fax: +1-412-623-7828
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37
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Sundaram R, Vasudevan D. Structural Basis of Nucleosome Recognition and Modulation. Bioessays 2020; 42:e1900234. [DOI: 10.1002/bies.201900234] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 05/05/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Rajivgandhi Sundaram
- Laboratory of Macromolecular Crystallography Institute of Life Sciences Bhubaneswar 751023 India
- Manipal Academy of Higher Education Manipal 576104 India
| | - Dileep Vasudevan
- Laboratory of Macromolecular Crystallography Institute of Life Sciences Bhubaneswar 751023 India
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38
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Kixmoeller K, Allu PK, Black BE. The centromere comes into focus: from CENP-A nucleosomes to kinetochore connections with the spindle. Open Biol 2020; 10:200051. [PMID: 32516549 PMCID: PMC7333888 DOI: 10.1098/rsob.200051] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Eukaryotic chromosome segregation relies upon specific connections from DNA to the microtubule-based spindle that forms at cell division. The chromosomal locus that directs this process is the centromere, where a structure called the kinetochore forms upon entry into mitosis. Recent crystallography and single-particle electron microscopy have provided unprecedented high-resolution views of the molecular complexes involved in this process. The centromere is epigenetically specified by nucleosomes harbouring a histone H3 variant, CENP-A, and we review recent progress on how it differentiates centromeric chromatin from the rest of the chromosome, the biochemical pathway that mediates its assembly and how two non-histone components of the centromere specifically recognize CENP-A nucleosomes. The core centromeric nucleosome complex (CCNC) is required to recruit a 16-subunit complex termed the constitutive centromere associated network (CCAN), and we highlight recent structures reported of the budding yeast CCAN. Finally, the structures of multiple modular sub-complexes of the kinetochore have been solved at near-atomic resolution, providing insight into how connections are made to the CCAN on one end and to the spindle microtubules on the other. One can now build molecular models from the DNA through to the physical connections to microtubules.
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Affiliation(s)
- Kathryn Kixmoeller
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Program in Biochemistry and Molecular Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Praveen Kumar Allu
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ben E Black
- Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Penn Center for Genome Integrity, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.,Graduate Program in Biochemistry and Molecular Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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39
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Cryo-EM structures of cardiac thin filaments reveal the 3D architecture of troponin. J Struct Biol 2020; 209:107450. [PMID: 31954841 DOI: 10.1016/j.jsb.2020.107450] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 01/06/2020] [Accepted: 01/12/2020] [Indexed: 02/06/2023]
Abstract
Troponin is an essential component of striated muscle and it regulates the sliding of actomyosin system in a calcium-dependent manner. Despite its importance, the structure of troponin has been elusive due to its high structural heterogeneity. In this study, we analyzed the 3D structures of murine cardiac thin filaments using a cryo-electron microscope equipped with a Volta phase plate (VPP). Contrast enhancement by a VPP enabled us to reconstruct the entire repeat of the thin filament. We determined the orientation of troponin relative to F-actin and tropomyosin, and characterized the interactions between troponin and tropomyosin. This study provides a structural basis for understanding the molecular mechanism of actomyosin system.
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40
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Melters DP, Pitman M, Rakshit T, Dimitriadis EK, Bui M, Papoian GA, Dalal Y. Intrinsic elasticity of nucleosomes is encoded by histone variants and calibrated by their binding partners. Proc Natl Acad Sci U S A 2019; 116:24066-24074. [PMID: 31712435 PMCID: PMC6883791 DOI: 10.1073/pnas.1911880116] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Histone variants fine-tune transcription, replication, DNA damage repair, and faithful chromosome segregation. Whether and how nucleosome variants encode unique mechanical properties to their cognate chromatin structures remains elusive. Here, using in silico and in vitro nanoindentation methods, extending to in vivo dissections, we report that histone variant nucleosomes are intrinsically more elastic than their canonical counterparts. Furthermore, binding proteins, which discriminate between histone variant nucleosomes, suppress this innate elasticity and also compact chromatin. Interestingly, when we overexpress the binding proteins in vivo, we also observe increased compaction of chromatin enriched for histone variant nucleosomes, correlating with diminished access. Taken together, these data suggest a plausible link between innate mechanical properties possessed by histone variant nucleosomes, the adaptability of chromatin states in vivo, and the epigenetic plasticity of the underlying locus.
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Affiliation(s)
- Daniël P Melters
- Laboratory Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Mary Pitman
- Laboratory Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
- Department of Chemistry and Biochemistry, Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742
| | - Tatini Rakshit
- Laboratory Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Emilios K Dimitriadis
- Scanning Probe Microscopy Unit, Biomedical Engineering and Physical Science Shared Resource, National Institute for Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892
| | - Minh Bui
- Laboratory Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Garegin A Papoian
- Department of Chemistry and Biochemistry, Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742;
| | - Yamini Dalal
- Laboratory Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892;
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Ali-Ahmad A, Bilokapić S, Schäfer IB, Halić M, Sekulić N. CENP-C unwraps the human CENP-A nucleosome through the H2A C-terminal tail. EMBO Rep 2019. [PMID: 31475439 DOI: 10.15252/embr.20194891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Centromeres are defined epigenetically by nucleosomes containing the histone H3 variant CENP-A, upon which the constitutive centromere-associated network of proteins (CCAN) is built. CENP-C is considered to be a central organizer of the CCAN. We provide new molecular insights into the structure of human CENP-A nucleosomes, in isolation and in complex with the CENP-C central region (CENP-CCR ), the main CENP-A binding module of human CENP-C. We establish that the short αN helix of CENP-A promotes DNA flexibility at the nucleosome ends, independently of the sequence it wraps. Furthermore, we show that, in vitro, two regions of human CENP-C (CENP-CCR and CENP-Cmotif ) both bind exclusively to the CENP-A nucleosome. We find CENP-CCR to bind with high affinity due to an extended hydrophobic area made up of CENP-AV532 and CENP-AV533 . Importantly, we identify two key conformational changes within the CENP-A nucleosome upon CENP-C binding. First, the loose DNA wrapping of CENP-A nucleosomes is further exacerbated, through destabilization of the H2A C-terminal tail. Second, CENP-CCR rigidifies the N-terminal tail of H4 in the conformation favoring H4K20 monomethylation, essential for a functional centromere.
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Affiliation(s)
- Ahmad Ali-Ahmad
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway
| | - Silvija Bilokapić
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Ingmar B Schäfer
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Munich, Germany
| | - Mario Halić
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Nikolina Sekulić
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo, Oslo, Norway.,Department of Chemistry, University of Oslo, Oslo, Norway
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Ali‐Ahmad A, Bilokapić S, Schäfer IB, Halić M, Sekulić N. CENP-C unwraps the human CENP-A nucleosome through the H2A C-terminal tail. EMBO Rep 2019; 20:e48913. [PMID: 31475439 PMCID: PMC6776904 DOI: 10.15252/embr.201948913] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 01/06/2023] Open
Abstract
Centromeres are defined epigenetically by nucleosomes containing the histone H3 variant CENP-A, upon which the constitutive centromere-associated network of proteins (CCAN) is built. CENP-C is considered to be a central organizer of the CCAN. We provide new molecular insights into the structure of human CENP-A nucleosomes, in isolation and in complex with the CENP-C central region (CENP-CCR ), the main CENP-A binding module of human CENP-C. We establish that the short αN helix of CENP-A promotes DNA flexibility at the nucleosome ends, independently of the sequence it wraps. Furthermore, we show that, in vitro, two regions of human CENP-C (CENP-CCR and CENP-Cmotif ) both bind exclusively to the CENP-A nucleosome. We find CENP-CCR to bind with high affinity due to an extended hydrophobic area made up of CENP-AV532 and CENP-AV533 . Importantly, we identify two key conformational changes within the CENP-A nucleosome upon CENP-C binding. First, the loose DNA wrapping of CENP-A nucleosomes is further exacerbated, through destabilization of the H2A C-terminal tail. Second, CENP-CCR rigidifies the N-terminal tail of H4 in the conformation favoring H4K20 monomethylation, essential for a functional centromere.
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Affiliation(s)
- Ahmad Ali‐Ahmad
- Centre for Molecular Medicine Norway (NCMM)Nordic EMBL PartnershipUniversity of OsloOsloNorway
| | - Silvija Bilokapić
- Department of Structural BiologySt. Jude Children's Research HospitalMemphisTNUSA
| | - Ingmar B Schäfer
- Department of Structural Cell BiologyMax Planck Institute of BiochemistryMunichGermany
| | - Mario Halić
- Department of Structural BiologySt. Jude Children's Research HospitalMemphisTNUSA
| | - Nikolina Sekulić
- Centre for Molecular Medicine Norway (NCMM)Nordic EMBL PartnershipUniversity of OsloOsloNorway
- Department of ChemistryUniversity of OsloOsloNorway
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ZCMM: A Novel Method Using Z-Curve Theory- Based and Position Weight Matrix for Predicting Nucleosome Positioning. Genes (Basel) 2019; 10:genes10100765. [PMID: 31569414 PMCID: PMC6827144 DOI: 10.3390/genes10100765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/25/2019] [Accepted: 09/26/2019] [Indexed: 02/04/2023] Open
Abstract
Nucleosomes are the basic units of eukaryotes. The accurate positioning of nucleosomes plays a significant role in understanding many biological processes such as transcriptional regulation mechanisms and DNA replication and repair. Here, we describe the development of a novel method, termed ZCMM, based on Z-curve theory and position weight matrix (PWM). The ZCMM was trained and tested using the nucleosomal and linker sequences determined by support vector machine (SVM) in Saccharomyces cerevisiae (S. cerevisiae), and experimental results showed that the sensitivity (Sn), specificity (Sp), accuracy (Acc), and Matthews correlation coefficient (MCC) values for ZCMM were 91.40%, 96.56%, 96.75%, and 0.88, respectively, and the average area under the receiver operating characteristic curve (AUC) value was 0.972. A ZCMM predictor was developed to predict nucleosome positioning in Homo sapiens (H. sapiens), Caenorhabditis elegans (C. elegans), and Drosophila melanogaster (D. melanogaster) genomes, and the accuracy (Acc) values were 77.72%, 85.34%, and 93.62%, respectively. The maximum AUC values of the four species were 0.982, 0.861, 0.912 and 0.911, respectively. Another independent dataset for S. cerevisiae was used to predict nucleosome positioning. Compared with the results of Wu's method, it was found that the Sn, Sp, Acc, and MCC of ZCMM results for S. cerevisiae were all higher, reaching 96.72%, 96.54%, 94.10%, and 0.88. Compared with the Guo's method 'iNuc-PseKNC', the results of ZCMM for D. melanogaster were better. Meanwhile, the ZCMM was compared with some experimental data in vitro and in vivo for S. cerevisiae, and the results showed that the nucleosomes predicted by ZCMM were highly consistent with those confirmed by these experiments. Therefore, it was further confirmed that the ZCMM method has good accuracy and reliability in predicting nucleosome positioning.
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