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Du F, Dai J, Jiao Y. Insights into a functional synthetic plant genome. THE NEW PHYTOLOGIST 2024; 244:46-50. [PMID: 39160666 DOI: 10.1111/nph.19979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Accepted: 07/01/2024] [Indexed: 08/21/2024]
Abstract
Synthetic genomics involves the design, assembly, and transfer of artificially synthesized DNA fragments into target hosts to replace the native genome and construct viable forms of life. With advances in DNA synthesis and assembly techniques, the application of synthetic genomics in viruses, bacteria, and yeast has improved our knowledge of genome organization and function. Multicellular eukaryotic organisms are characterized by larger genomes, more complex epigenetic regulation, and widespread transposable elements, making genome synthesis challenging. Recently, the first synthetic multicellular eukaryotic organism was generated in the model plant Physcomitrium patens with a partially synthetic chromosome arm. Here, we introduce the design and assembly principles of moss genome synthesis. We also discuss the remaining technical barriers in the application of synthetic genomics in seed plants.
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Affiliation(s)
- Fei Du
- Institute of Genetics and Developmental Biology, Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China
- Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Junbiao Dai
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Key Laboratory of Synthetic Biology, Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China
- Shenzhen Key Laboratory of Synthetic Genomics, Guangdong Provincial Key Laboratory of Synthetic Genomics, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
| | - Yuling Jiao
- State Key Laboratory for Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
- Shandong Laboratory of Advanced Agricultural Sciences in Weifang, Peking University Institute of Advanced Agricultural Sciences, Weifang, Shandong, 261325, China
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2
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Vicars H, Karg T, Mills A, Sullivan W. Acentric chromosome congression and alignment on the metaphase plate via kinetochore-independent forces in Drosophila. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.14.567057. [PMID: 38798431 PMCID: PMC11118298 DOI: 10.1101/2023.11.14.567057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Chromosome congression and alignment on the metaphase plate involves lateral and microtubule plus-end interactions with the kinetochore. Here we take advantage of our ability to efficiently generate a GFP-marked acentric X chromosome fragment in Drosophila neuroblasts to identify forces acting on chromosome arms that drive congression and alignment. We find acentrics efficiently align on the metaphase plate, often more rapidly than kinetochore-bearing chromosomes. Unlike intact chromosomes, the paired sister acentrics oscillate as they move to and reside on the metaphase plate in a plane distinct and significantly further from the main mass of intact chromosomes. Consequently, at anaphase onset acentrics are oriented either parallel or perpendicular to the spindle. Parallel-oriented sisters separate by sliding while those oriented perpendicularly separate via unzipping. This oscillation, together with the fact that in monopolar spindles acentrics are rapidly shunted away from the poles, indicates that distributed plus-end directed forces are primarily responsible for acentric migration. This conclusion is supported by the observation that reduction of EB1 preferentially disrupts acentric alignment. In addition, reduction of Klp3a activity, a gene required for the establishment of pole-to-pole microtubules, preferentially disrupts acentric alignment. Taken together these studies suggest that plus-end forces mediated by the outer pole-to-pole microtubules are primarily responsible for acentric metaphase alignment. Surprisingly, we find that a small fraction of sister acentrics are anti-parallel aligned indicating that the kinetochore is required to ensure parallel alignment of sister chromatids. Finally, we find induction of acentric chromosome fragments results in a global reorganization of the congressed chromosomes into a torus configuration. Article Summary The kinetochore serves as a site for attaching microtubules and allows for successful alignment, separation, and segregation of replicated sister chromosomes during cell division. However, previous studies have revealed that sister chromosomes without kinetochores (acentrics) often align to the metaphase plate, undergo separation and segregation, and are properly transmitted to daughter cells. In this study, we discuss the forces acting on chromosomes, independent of the kinetochore, underlying their successful alignment in early mitosis.
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Lim KK, Lam UTF, Li Y, Zeng YB, Yang H, Chen ES. Set2 regulates Ccp1 and Swc2 to ensure centromeric stability by retargeting CENP-A. Nucleic Acids Res 2024; 52:4198-4214. [PMID: 38442274 PMCID: PMC11077061 DOI: 10.1093/nar/gkae084] [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: 05/02/2023] [Revised: 01/24/2024] [Accepted: 01/29/2024] [Indexed: 03/07/2024] Open
Abstract
Precise positioning of the histone-H3 variant, CENP-A, ensures centromere stability and faithful chromosomal segregation. Mislocalization of CENP-A to extra-centromeric loci results in aneuploidy and compromised cell viability associated with formation of ectopic kinetochores. The mechanism that retargets mislocalized CENP-A back to the centromere is unclarified. We show here that the downregulation of the histone H3 lysine 36 (H3K36) methyltransferase Set2 can preserve centromere localization of a temperature-sensitive mutant cnp1-1 Schizosaccharomyces pombe CENP-A (SpCENP-A) protein and reverse aneuploidy by redirecting mislocalized SpCENP-A back to centromere from ribosomal DNA (rDNA) loci, which serves as a sink for the delocalized SpCENP-A. Downregulation of set2 augments Swc2 (SWR1 complex DNA-binding module) expression and releases histone chaperone Ccp1 from the centromeric reservoir. Swc2 and Ccp1 are directed to the rDNA locus to excavate the SpCENP-Acnp1-1, which is relocalized to the centromere in a manner dependent on canonical SpCENP-A loaders, including Mis16, Mis17 and Mis18, thereby conferring cell survival and safeguarding chromosome segregation fidelity. Chromosome missegregation is a severe genetic instability event that compromises cell viability. This mechanism thus promotes CENP-A presence at the centromere to maintain genomic stability.
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Affiliation(s)
- Kim Kiat Lim
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ulysses Tsz Fung Lam
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Ying Li
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Cancer Science Institute, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yi Bing Zeng
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Henry Yang
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Cancer Science Institute, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- National University Health System, Singapore
| | - Ee Sin Chen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- National University Health System, Singapore
- Integrative Sciences & Engineering Programme, National University of Singapore, Singapore
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4
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Hu C, Zhu XT, He MH, Shao Y, Qin Z, Wu ZJ, Zhou JQ. Elimination of subtelomeric repeat sequences exerts little effect on telomere essential functions in Saccharomyces cerevisiae. eLife 2024; 12:RP91223. [PMID: 38656297 DOI: 10.7554/elife.91223] [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] [Indexed: 04/26/2024] Open
Abstract
Telomeres, which are chromosomal end structures, play a crucial role in maintaining genome stability and integrity in eukaryotes. In the baker's yeast Saccharomyces cerevisiae, the X- and Y'-elements are subtelomeric repetitive sequences found in all 32 and 17 telomeres, respectively. While the Y'-elements serve as a backup for telomere functions in cells lacking telomerase, the function of the X-elements remains unclear. This study utilized the S. cerevisiae strain SY12, which has three chromosomes and six telomeres, to investigate the role of X-elements (as well as Y'-elements) in telomere maintenance. Deletion of Y'-elements (SY12YΔ), X-elements (SY12XYΔ+Y), or both X- and Y'-elements (SY12XYΔ) did not impact the length of the terminal TG1-3 tracks or telomere silencing. However, inactivation of telomerase in SY12YΔ, SY12XYΔ+Y, and SY12XYΔ cells resulted in cellular senescence and the generation of survivors. These survivors either maintained their telomeres through homologous recombination-dependent TG1-3 track elongation or underwent microhomology-mediated intra-chromosomal end-to-end joining. Our findings indicate the non-essential role of subtelomeric X- and Y'-elements in telomere regulation in both telomerase-proficient and telomerase-null cells and suggest that these elements may represent remnants of S. cerevisiae genome evolution. Furthermore, strains with fewer or no subtelomeric elements exhibit more concise telomere structures and offer potential models for future studies in telomere biology.
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Affiliation(s)
- Can Hu
- The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Xue-Ting Zhu
- The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Ming-Hong He
- The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Yangyang Shao
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Zhongjun Qin
- Key Laboratory of Synthetic Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
| | - Zhi-Jing Wu
- The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
| | - Jin-Qiu Zhou
- The State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai, China
- Key Laboratory of Systems Health Science of Zhejiang Province, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, China
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Messer CL, Fox DT. Broken chromosomes heading into mitosis: More than one way to patch a flat tire. J Cell Biol 2024; 223:e202401085. [PMID: 38477879 PMCID: PMC10937182 DOI: 10.1083/jcb.202401085] [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: 01/17/2024] [Revised: 02/22/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
A cell dealing with a broken chromosome in mitosis is like a driver dealing with a flat tire on the highway: damage repair must occur under non-ideal circumstances. Mitotic chromosome breaks encounter problems related to structures called micronuclei. These aberrant nuclei are linked to cell death, mutagenesis, and cancer. In the last few years, a flurry of studies illuminated two mechanisms that prevent mitotic problems related to micronuclei. One mechanism prevents micronuclei from forming during mitosis and involves DNA Polymerase Theta, a DNA repair regulator that patches up broken mitotic chromosomes. A second mechanism is activated after micronuclei form and then rupture, and involves CIP2A and TOPBP1 proteins, which patch micronuclear fragments to promote their subsequent mitotic segregation. Here, we review recent progress in this field of mitotic DNA damage and discuss why multiple mechanisms exist. Future studies in this exciting area will reveal new DNA break responses and inform therapeutic strategies.
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Affiliation(s)
- C. Luke Messer
- Department of Biology, St. Bonaventure University, St. Bonaventure, NY, USA
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Donald T. Fox
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
- Duke Regeneration Center, Duke University Medical Center, Durham, NC, USA
- Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA
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Pei D, Yu X, Fu W, Ma X, Fang J. The evolution and formation of centromeric repeats analysis in Vitis vinifera. PLANTA 2024; 259:99. [PMID: 38522063 DOI: 10.1007/s00425-024-04374-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 03/03/2024] [Indexed: 03/25/2024]
Abstract
MAIN CONCLUSION Six grape centromere-specific markers for cytogenetics were mined by combining genetic and immunological assays, and the possible evolution mechanism of centromeric repeats was analyzed. Centromeric histone proteins are functionally conserved; however, centromeric repetitive DNA sequences may represent considerable diversity in related species. Therefore, studying the characteristics and structure of grape centromere repeat sequences contributes to a deeper understanding of the evolutionary process of grape plants, including their origin and mechanisms of polyploidization. Plant centromeric regions are mainly composed of repetitive sequences, including SatDNA and transposable elements (TE). In this research, the characterization of centromere sequences in the whole genome of grapevine (Vitis vinifera L.) has been conducted. Five centromeric tandem repeat sequences (Vv1, Vv2, Vv5, Vv6, and Vv8) and one long terminal repeat (LTR) sequence Vv24 were isolated. These sequences had different centromeric distributions, which indicates that grape centromeric sequences may undergo rapid evolution. The existence of extrachromosomal circular DNA (eccDNA) and gene expression in CenH3 subdomain region may provide various potential mechanisms for the generation of new centromeric regions.
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Affiliation(s)
- Dan Pei
- Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, China
| | - Xue Yu
- Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, China
| | - Weihong Fu
- Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, China
| | - Xuhui Ma
- College of Life Sciences, Zaozhuang University, Zaozhuang, 277000, China
| | - Jinggui Fang
- Key Laboratory of Genetics and Fruit Development, College of Horticulture, Nanjing Agricultural University, Nanjing, China.
- Fruit Crop Genetic Improvement and Seedling Propagation Engineering Center of Jiangsu Province, Nanjing, 210095, China.
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London N, Medina-Pritchard B, Spanos C, Rappsilber J, Jeyaprakash AA, Allshire RC. Direct recruitment of Mis18 to interphase spindle pole bodies promotes CENP-A chromatin assembly. Curr Biol 2023; 33:4187-4201.e6. [PMID: 37714149 DOI: 10.1016/j.cub.2023.08.063] [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: 06/21/2023] [Revised: 08/04/2023] [Accepted: 08/22/2023] [Indexed: 09/17/2023]
Abstract
CENP-A chromatin specifies mammalian centromere identity, and its chaperone HJURP replenishes CENP-A when recruited by the Mis18 complex (Mis18C) via M18BP1/KNL2 to CENP-C at kinetochores during interphase. However, the Mis18C recruitment mechanism remains unresolved in species lacking M18BP1, such as fission yeast. Fission yeast centromeres cluster at G2 spindle pole bodies (SPBs) when CENP-ACnp1 is replenished and where Mis18C also localizes. We show that SPBs play an unexpected role in concentrating Mis18C near centromeres through the recruitment of Mis18 by direct binding to the major SPB linker of nucleoskeleton and cytoskeleton (LINC) component Sad1. Mis18C recruitment by Sad1 is important for CENP-ACnp1 chromatin establishment and acts in parallel with a CENP-C-mediated Mis18C recruitment pathway to maintain centromeric CENP-ACnp1 but operates independently of Sad1-mediated centromere clustering. SPBs therefore provide a non-chromosomal scaffold for both Mis18C recruitment and centromere clustering during G2. This centromere-independent Mis18-SPB recruitment provides a mechanism that governs de novo CENP-ACnp1 chromatin assembly by the proximity of appropriate sequences to SPBs and highlights how nuclear spatial organization influences centromere identity.
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Affiliation(s)
- Nitobe London
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Bethan Medina-Pritchard
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Christos Spanos
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Juri Rappsilber
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK; Institute of Biotechnology, Technische Universität, 13355 Berlin, Germany
| | - A Arockia Jeyaprakash
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK; Gene Center and Department of Biochemistry, Ludwig-Maximilians-Universität München, 81377 Munich, Germany
| | - Robin C Allshire
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK.
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Kuse R, Ishii K. Flexible Attachment and Detachment of Centromeres and Telomeres to and from Chromosomes. Biomolecules 2023; 13:1016. [PMID: 37371596 DOI: 10.3390/biom13061016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/15/2023] [Accepted: 06/18/2023] [Indexed: 06/29/2023] Open
Abstract
Accurate transmission of genomic information across multiple cell divisions and generations, without any losses or errors, is fundamental to all living organisms. To achieve this goal, eukaryotes devised chromosomes. Eukaryotic genomes are represented by multiple linear chromosomes in the nucleus, each carrying a centromere in the middle, a telomere at both ends, and multiple origins of replication along the chromosome arms. Although all three of these DNA elements are indispensable for chromosome function, centromeres and telomeres possess the potential to detach from the original chromosome and attach to new chromosomal positions, as evident from the events of telomere fusion, centromere inactivation, telomere healing, and neocentromere formation. These events seem to occur spontaneously in nature but have not yet been elucidated clearly, because they are relatively infrequent and sometimes detrimental. To address this issue, experimental setups have been developed using model organisms such as yeast. In this article, we review some of the key experiments that provide clues as to the extent to which these paradoxical and elusive features of chromosomally indispensable elements may become valuable in the natural context.
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Affiliation(s)
- Riku Kuse
- Laboratory of Chromosome Function and Regulation, Graduate School of Engineering, Kochi University of Technology, Kochi 782-8502, Japan
| | - Kojiro Ishii
- Laboratory of Chromosome Function and Regulation, Graduate School of Engineering, Kochi University of Technology, Kochi 782-8502, Japan
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9
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Coelho MA, Ianiri G, David-Palma M, Theelen B, Goyal R, Narayanan A, Lorch JM, Sanyal K, Boekhout T, Heitman J. Frequent transitions in mating-type locus chromosomal organization in Malassezia and early steps in sexual reproduction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.25.534224. [PMID: 36993584 PMCID: PMC10055393 DOI: 10.1101/2023.03.25.534224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Fungi in the basidiomycete genus Malassezia are the most prevalent eukaryotic microbes resident on the skin of human and other warm-blooded animals and have been implicated in skin diseases and systemic disorders. Analysis of Malassezia genomes revealed that key adaptations to the skin microenvironment have a direct genomic basis, and the identification of mating/meiotic genes suggests a capacity to reproduce sexually, even though no sexual cycle has yet been observed. In contrast to other bipolar or tetrapolar basidiomycetes that have either two linked mating-type-determining ( MAT ) loci or two MAT loci on separate chromosomes, in Malassezia species studied thus far the two MAT loci are arranged in a pseudobipolar configuration (linked on the same chromosome but capable of recombining). By incorporating newly generated chromosome-level genome assemblies, and an improved Malassezia phylogeny, we infer that the pseudobipolar arrangement was the ancestral state of this group and revealed six independent transitions to tetrapolarity, seemingly driven by centromere fission or translocations in centromere- flanking regions. Additionally, in an approach to uncover a sexual cycle, Malassezia furfur strains were engineered to express different MAT alleles in the same cell. The resulting strains produce hyphae reminiscent of early steps in sexual development and display upregulation of genes associated with sexual development as well as others encoding lipases and a protease potentially relevant for pathogenesis of the fungus. Our study reveals a previously unseen genomic relocation of mating-type loci in fungi and provides insight towards the discovery of a sexual cycle in Malassezia , with possible implications for pathogenicity. Significance Statement Malassezia , the dominant fungal group of the mammalian skin microbiome, is associated with numerous skin disorders. Sexual development and yeast-to-hyphae transitions, governed by genes at two mating-type ( MAT ) loci, are thought to be important for fungal pathogenicity. However, Malassezia sexual reproduction has never been observed. Here, we used chromosome-level assemblies and comparative genomics to uncover unforeseen transitions in MAT loci organization within Malassezia , possibly related with fragility of centromeric-associated regions. Additionally, by expressing different MAT alleles in the same cell, we show that Malassezia can undergo hyphal development and this phenotype is associated with increased expression of key mating genes along with other genes known to be virulence factors, providing a possible connection between hyphal development, sexual reproduction, and pathogenicity.
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Affiliation(s)
- Marco A. Coelho
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Giuseppe Ianiri
- Department of Agricultural, Environmental and Food Sciences, University of Molise, Campobasso 86100, Italy
| | - Márcia David-Palma
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Bart Theelen
- Westerdijk Fungal Biodiversity Institute, Utrecht 3584 CT, The Netherlands
| | - Rohit Goyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064, India
| | - Aswathy Narayanan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064, India
| | - Jeffrey M. Lorch
- U.S. Geological Survey, National Wildlife Health Center, Madison, WI 53711, USA
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru 560064, India
| | - Teun Boekhout
- Westerdijk Fungal Biodiversity Institute, Utrecht 3584 CT, The Netherlands
- College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA
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10
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Ishikawa K, Saitoh S. Transcriptional Regulation Technology for Gene Perturbation in Fission Yeast. Biomolecules 2023; 13:716. [PMID: 37189462 PMCID: PMC10135669 DOI: 10.3390/biom13040716] [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: 03/21/2023] [Revised: 04/20/2023] [Accepted: 04/20/2023] [Indexed: 05/17/2023] Open
Abstract
Isolation and introduction of genetic mutations is the primary approach to characterize gene functions in model yeasts. Although this approach has proven very powerful, it is not applicable to all genes in these organisms. For example, introducing defective mutations into essential genes causes lethality upon loss of function. To circumvent this difficulty, conditional and partial repression of target transcription is possible. While transcriptional regulation techniques, such as promoter replacement and 3' untranslated region (3'UTR) disruption, are available for yeast systems, CRISPR-Cas-based technologies have provided additional options. This review summarizes these gene perturbation technologies, including recent advances in methods based on CRISPR-Cas systems for Schizosaccharomyces pombe. We discuss how biological resources afforded by CRISPRi can promote fission yeast genetics.
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Affiliation(s)
- Ken Ishikawa
- Department of Cell Biology, Institute of Life Science, Kurume University, Asahi-machi 67, Fukuoka 830-0011, Japan
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11
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Fukagawa T, Kakutani T. Transgenerational epigenetic control of constitutive heterochromatin, transposons, and centromeres. Curr Opin Genet Dev 2023; 78:102021. [PMID: 36716679 DOI: 10.1016/j.gde.2023.102021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 12/20/2022] [Accepted: 01/04/2023] [Indexed: 01/30/2023]
Abstract
Epigenetic mechanisms are important not only for development but also for genome stability and chromosome dynamics. The latter types of epigenetic controls can often be transgenerational. Here, we review recent progress in two examples of transgenerational epigenetic control: i) the control of constitutive heterochromatin and transposable elements and ii) epigenetic mechanisms that regulate centromere specification and functions. We also discuss the biological significance of enigmatic associations among centromeres, transposons, and constitutive heterochromatin.
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Affiliation(s)
- Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan. https://twitter.com/tatsuofukagawa1
| | - Tetsuji Kakutani
- Department of Biological Sciences, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.
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12
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Dong Q, Li F. Cell cycle control of kinetochore assembly. Nucleus 2022; 13:208-220. [PMID: 36037227 PMCID: PMC9427032 DOI: 10.1080/19491034.2022.2115246] [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] [Indexed: 10/28/2022] Open
Abstract
The kinetochore is a large proteinaceous structure assembled on the centromeres of chromosomes. The complex machinery links chromosomes to the mitotic spindle and is essential for accurate chromosome segregation during cell division. The kinetochore is composed of two submodules: the inner and outer kinetochore. The inner kinetochore is assembled on centromeric chromatin and persists with centromeres throughout the cell cycle. The outer kinetochore attaches microtubules to the inner kinetochore, and assembles only during mitosis. The review focuses on recent advances in our understanding of the mechanisms governing the proper assembly of the outer kinetochore during mitosis and highlights open questions for future investigation.
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Affiliation(s)
- Qianhua Dong
- Department of Biology, New York University, New York, NY, USA
| | - Fei Li
- Department of Biology, New York University, New York, NY, USA
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13
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Gu X, Ye T, Zhang XR, Nie L, Wang H, Li W, Lu R, Fu C, Du LL, Zhou JQ. Single-chromosome fission yeast models reveal the configuration robustness of a functional genome. Cell Rep 2022; 40:111237. [PMID: 36001961 DOI: 10.1016/j.celrep.2022.111237] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 05/02/2022] [Accepted: 07/28/2022] [Indexed: 11/03/2022] Open
Abstract
In eukaryotic organisms, genetic information is usually carried on multiple chromosomes. Whether and how the number and configuration of chromosomes affect organismal fitness and speciation remain unclear. Here, we have successfully established several single-chromosome fission yeast Schizosaccharomyces pombe strains, in which the three natural chromosomes have been fused into one giant chromosome in different orders. Chromosome fusions accompanied by the deletions of telomeres and centromeres result in the loss of chromosomal interactions and a drastic change of global chromosome organization, but alter gene expression marginally. The single-chromosome strains display little defects in cell morphology, mitosis, genotoxin sensitivity, and meiosis. Crosses between a wild-type strain and a single-chromosome strain or between two single-chromosome strains with different fusion orders suffer defective meiosis and poor spore viability. We conclude that eukaryotic genomes are robust against dramatic chromosomal reconfiguration, and stochastic changes in chromosome number and genome organization during evolution underlie reproductive isolation and speciation.
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Affiliation(s)
- Xin Gu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tiantian Ye
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiao-Ran Zhang
- National Institute of Biological Sciences, Beijing 102206, China
| | - Lingyun Nie
- Ministry of Education Key Laboratory for Membrane-less Organelles & Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Huan Wang
- Frasergen Bioinformatics, Wuhan, China
| | - Wei Li
- Frasergen Bioinformatics, Wuhan, China
| | - Rui Lu
- Frasergen Bioinformatics, Wuhan, China
| | - Chuanhai Fu
- Ministry of Education Key Laboratory for Membrane-less Organelles & Cellular Dynamics, CAS Center for Excellence in Molecular Cell Sciences, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei 230027, China
| | - Li-Lin Du
- National Institute of Biological Sciences, Beijing 102206, China.
| | - Jin-Qiu Zhou
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China; Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of the Chinese Academy of Sciences, Hangzhou 310024, China.
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14
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Palazzo A, Piccolo I, Minervini CF, Purgato S, Capozzi O, D'Addabbo P, Cumbo C, Albano F, Rocchi M, Catacchio CR. Genome characterization and CRISPR-Cas9 editing of a human neocentromere. Chromosoma 2022; 131:239-251. [PMID: 35978051 DOI: 10.1007/s00412-022-00779-y] [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: 04/29/2022] [Revised: 07/20/2022] [Accepted: 08/12/2022] [Indexed: 11/27/2022]
Abstract
The maintenance of genome integrity is ensured by proper chromosome inheritance during mitotic and meiotic cell divisions. The chromosomal counterpart responsible for chromosome segregation to daughter cells is the centromere, at which the spindle apparatus attaches through the kinetochore. Although all mammalian centromeres are primarily composed of megabase-long repetitive sequences, satellite-free human neocentromeres have been described. Neocentromeres and evolutionary new centromeres have revolutionized traditional knowledge about centromeres. Over the past 20 years, insights have been gained into their organization, but in spite of these advancements, the mechanisms underlying their formation and evolution are still unclear. Today, through modern and increasingly accessible genome editing and long-read sequencing techniques, research in this area is undergoing a sudden acceleration. In this article, we describe the primary sequence of a previously described human chromosome 3 neocentromere and observe its possible evolution and repair results after a chromosome breakage induced through CRISPR-Cas9 technologies. Our data represent an exciting advancement in the field of centromere/neocentromere evolution and chromosome stability.
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Affiliation(s)
- Antonio Palazzo
- Department of Biology, University of Bari Aldo Moro, Bari, Italy.
| | - Ilaria Piccolo
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Crescenzio Francesco Minervini
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Stefania Purgato
- Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy
| | - Oronzo Capozzi
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Pietro D'Addabbo
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
| | - Cosimo Cumbo
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Francesco Albano
- Department of Emergency and Organ Transplantation (D.E.T.O.), Hematology and Stem Cell Transplantation Unit, University of Bari Aldo Moro, Bari, Italy
| | - Mariano Rocchi
- Department of Biology, University of Bari Aldo Moro, Bari, Italy
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15
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Kumon T, Lampson MA. Evolution of eukaryotic centromeres by drive and suppression of selfish genetic elements. Semin Cell Dev Biol 2022; 128:51-60. [PMID: 35346579 PMCID: PMC9232976 DOI: 10.1016/j.semcdb.2022.03.026] [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: 01/11/2022] [Revised: 03/20/2022] [Accepted: 03/20/2022] [Indexed: 10/18/2022]
Abstract
Despite the universal requirement for faithful chromosome segregation, eukaryotic centromeres are rapidly evolving. It is hypothesized that rapid centromere evolution represents an evolutionary arms race between selfish genetic elements that drive, or propagate at the expense of organismal fitness, and mechanisms that suppress fitness costs. Selfish centromere DNA achieves preferential inheritance in female meiosis by recruiting more effector proteins that alter spindle microtubule interaction dynamics. Parallel pathways for effector recruitment are adaptively evolved to suppress functional differences between centromeres. Opportunities to drive are not limited to female meiosis, and selfish transposons, plasmids and B chromosomes also benefit by maximizing their inheritance. Rapid evolution of selfish genetic elements can diversify suppressor mechanisms in different species that may cause hybrid incompatibility.
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Affiliation(s)
- Tomohiro Kumon
- Howard Hughes Medical Institute, Whitehead Institute for Biomedical Research, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Michael A Lampson
- Department of Biology, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA.
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16
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Wu W, McHugh T, Kelly DA, Pidoux AL, Allshire RC. Establishment of centromere identity is dependent on nuclear spatial organization. Curr Biol 2022; 32:3121-3136.e6. [PMID: 35830853 PMCID: PMC9616734 DOI: 10.1016/j.cub.2022.06.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/24/2022] [Accepted: 06/15/2022] [Indexed: 11/15/2022]
Abstract
The establishment of centromere-specific CENP-A chromatin is influenced by epigenetic and genetic processes. Central domain sequences from fission yeast centromeres are preferred substrates for CENP-ACnp1 incorporation, but their use is context dependent, requiring adjacent heterochromatin. CENP-ACnp1 overexpression bypasses heterochromatin dependency, suggesting that heterochromatin ensures exposure to conditions or locations permissive for CENP-ACnp1 assembly. Centromeres cluster around spindle-pole bodies (SPBs). We show that heterochromatin-bearing minichromosomes localize close to SPBs, consistent with this location promoting CENP-ACnp1 incorporation. We demonstrate that heterochromatin-independent de novo CENP-ACnp1 chromatin assembly occurs when central domain DNA is placed near, but not far from, endogenous centromeres or neocentromeres. Moreover, direct tethering of central domain DNA at SPBs permits CENP-ACnp1 assembly, suggesting that the nuclear compartment surrounding SPBs is permissive for CENP-ACnp1 incorporation because target sequences are exposed to high levels of CENP-ACnp1 and associated assembly factors. Thus, nuclear spatial organization is a key epigenetic factor that influences centromere identity.
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Affiliation(s)
- Weifang Wu
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Toni McHugh
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - David A Kelly
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Alison L Pidoux
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK
| | - Robin C Allshire
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, Scotland, UK.
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17
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Gavade JN, Black BE. Chromosomes: A nuclear neighborhood conducive to centromere formation. Curr Biol 2022; 32:R776-R778. [PMID: 35882197 DOI: 10.1016/j.cub.2022.06.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Centromere identity is specified by nucleosomes containing the histone variant CENP-A. A new study reveals that subnuclear location dictates the efficiency with which a new centromere forms.
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Affiliation(s)
- 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
| | - 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.
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18
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Barbosa AC, Xu Z, Karari K, Williams W, Hauf S, Brown WRA. Mutation and selection explain why many eukaryotic centromeric DNA sequences are often A + T rich. Nucleic Acids Res 2021; 50:579-596. [PMID: 34928384 PMCID: PMC8754631 DOI: 10.1093/nar/gkab1219] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 11/16/2021] [Accepted: 11/30/2021] [Indexed: 01/10/2023] Open
Abstract
We have used chromosome engineering to replace native centromeric DNA with different test sequences at native centromeres in two different strains of the fission yeast Schizosaccharomyces pombe and have discovered that A + T rich DNA, whether synthetic or of bacterial origin, will function as a centromere in this species. Using genome size as a surrogate for the inverse of effective population size (Ne) we also show that the relative A + T content of centromeric DNA scales with Ne across 43 animal, fungal and yeast (Opisthokonta) species. This suggests that in most of these species the A + T content of the centromeric DNA is determined by a balance between selection and mutation. Combining the experimental results and the evolutionary analyses allows us to conclude that A + T rich DNA of almost any sequence will function as a centromere in most Opisthokonta species. The fact that many G/C to A/T substitutions are unlikely to be selected against may contribute to the rapid evolution of centromeric DNA. We also show that a neo-centromere sequence is not simply a weak version of native centromeric DNA and suggest that neo-centromeres require factors either for their propagation or establishment in addition to those required by native centromeres.
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Affiliation(s)
- Anne C Barbosa
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, NG7 2UH, UK
| | - Zhengyao Xu
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, NG7 2UH, UK
| | - Kazhal Karari
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, NG7 2UH, UK
| | - Wendi Williams
- Virginia Tech, Department of Biological Sciences, Fralin Life Sciences Institute, 1015 Life Science Circle, Blacksburg, VA 24061, USA
| | - Silke Hauf
- Virginia Tech, Department of Biological Sciences, Fralin Life Sciences Institute, 1015 Life Science Circle, Blacksburg, VA 24061, USA
| | - William R A Brown
- School of Life Sciences, University of Nottingham, Queen's Medical Centre, NG7 2UH, UK
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19
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Clay DE, Bretscher HS, Jezuit EA, Bush KB, Fox DT. Persistent DNA damage signaling and DNA polymerase theta promote broken chromosome segregation. J Cell Biol 2021; 220:e202106116. [PMID: 34613334 PMCID: PMC8500225 DOI: 10.1083/jcb.202106116] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 08/24/2021] [Accepted: 09/14/2021] [Indexed: 01/16/2023] Open
Abstract
Cycling cells must respond to DNA double-strand breaks (DSBs) to avoid genome instability. Missegregation of chromosomes with DSBs during mitosis results in micronuclei, aberrant structures linked to disease. How cells respond to DSBs during mitosis is incompletely understood. We previously showed that Drosophilamelanogaster papillar cells lack DSB checkpoints (as observed in many cancer cells). Here, we show that papillar cells still recruit early acting repair machinery (Mre11 and RPA3) and the Fanconi anemia (FA) protein Fancd2 to DSBs. These proteins persist as foci on DSBs as cells enter mitosis. Repair foci are resolved in a stepwise manner during mitosis. DSB repair kinetics depends on both monoubiquitination of Fancd2 and the alternative end-joining protein DNA polymerase θ. Disruption of either or both of these factors causes micronuclei after DNA damage, which disrupts intestinal organogenesis. This study reveals a mechanism for how cells with inactive DSB checkpoints can respond to DNA damage that persists into mitosis.
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Affiliation(s)
- Delisa E. Clay
- Department of Cell Biology, Duke University School of Medicine, Durham, NC
| | - Heidi S. Bretscher
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC
| | - Erin A. Jezuit
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC
| | - Korie B. Bush
- University Program in Genetics and Genomics, Duke University School of Medicine, Durham, NC
| | - Donald T. Fox
- Department of Cell Biology, Duke University School of Medicine, Durham, NC
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC
- University Program in Genetics and Genomics, Duke University School of Medicine, Durham, NC
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20
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Kim T. Epigenetic control of centromere: what can we learn from neocentromere? Genes Genomics 2021; 44:317-325. [PMID: 34843088 DOI: 10.1007/s13258-021-01193-x] [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: 10/30/2021] [Accepted: 11/16/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND The centromere is the special region on a chromosome, which serves as the site for assembly of kinetochore complex and is essential for maintaining genomic integrity. Neocentromeres are new centromeres that form on the non-centromeric regions of the chromosome when the natural centromere is disrupted or inactivated. Although neocentromeres lack the typical features found in centromeres, cells with neocentromeres divide normally during mitosis and meiosis. Neocentromeres not only arise naturally but their formation can also be induced experimentally. Therefore, neocentromeres are a great tool for studying functions and formation of centromeres. OBJECTIVE To study neocentromeres and use that knowledge to gain insights into the epigenetic regulation of canonical centromeres. DISCUSSION Here, we review the characteristics of naturally occurring centromeres and neocentromeres and those of experimentally induced neocentromeres. We also discuss the mechanism of centromere formation and epigenetic regulation of centromere function, which we learned from studying the neocentromeres. Although neocentromeres lack main features of centromeres, such as presence of repetitive ⍺-satellite DNA and pericentric heterochromatin, they behave quite similar to the canonical centromere, indicating the epigenetic nature of the centromere. Still, further investigation will help to understand the formation and maintenance of the centromere, and the correlation to human diseases. CONCLUSION Neocentromeres helped us to understand the formation of canonical centromeres. Also, since neocentromeres are associated with certain cancer types, knowledge about them could be helpful to treat cancer.
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Affiliation(s)
- Taekyung Kim
- Department of Biology Education, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Korea.
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21
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Clay DE, Fox DT. DNA Damage Responses during the Cell Cycle: Insights from Model Organisms and Beyond. Genes (Basel) 2021; 12:1882. [PMID: 34946831 PMCID: PMC8701014 DOI: 10.3390/genes12121882] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/25/2022] Open
Abstract
Genome damage is a threat to all organisms. To respond to such damage, DNA damage responses (DDRs) lead to cell cycle arrest, DNA repair, and cell death. Many DDR components are highly conserved, whereas others have adapted to specific organismal needs. Immense progress in this field has been driven by model genetic organism research. This review has two main purposes. First, we provide a survey of model organism-based efforts to study DDRs. Second, we highlight how model organism study has contributed to understanding how specific DDRs are influenced by cell cycle stage. We also look forward, with a discussion of how future study can be expanded beyond typical model genetic organisms to further illuminate how the genome is protected.
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Affiliation(s)
- Delisa E. Clay
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA;
| | - Donald T. Fox
- Department of Cell Biology, Duke University School of Medicine, Durham, NC 27710, USA;
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
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22
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Subtelomeric Chromatin in the Fission Yeast S. pombe. Microorganisms 2021; 9:microorganisms9091977. [PMID: 34576871 PMCID: PMC8466458 DOI: 10.3390/microorganisms9091977] [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: 08/10/2021] [Revised: 09/06/2021] [Accepted: 09/14/2021] [Indexed: 01/15/2023] Open
Abstract
Telomeres play important roles in safeguarding the genome. The specialized repressive chromatin that assembles at telomeres and subtelomeric domains is key to this protective role. However, in many organisms, the repetitive nature of telomeric and subtelomeric sequences has hindered research efforts. The fission yeast S. pombe has provided an important model system for dissection of chromatin biology due to the relative ease of genetic manipulation and strong conservation of important regulatory proteins with higher eukaryotes. Telomeres and the telomere-binding shelterin complex are highly conserved with mammals, as is the assembly of constitutive heterochromatin at subtelomeres. In this review, we seek to summarize recent work detailing the assembly of distinct chromatin structures within subtelomeric domains in fission yeast. These include the heterochromatic SH subtelomeric domains, the telomere-associated sequences (TAS), and ST chromatin domains that assemble highly condensed chromatin clusters called knobs. Specifically, we review new insights into the sequence of subtelomeric domains, the distinct types of chromatin that assemble on these sequences and how histone H3 K36 modifications influence these chromatin structures. We address the interplay between the subdomains of chromatin structure and how subtelomeric chromatin is influenced by both the telomere-bound shelterin complexes and by euchromatic chromatin regulators internal to the subtelomeric domain. Finally, we demonstrate that telomere clustering, which is mediated via the condensed ST chromatin knob domains, does not depend on knob assembly within these domains but on Set2, which mediates H3K36 methylation.
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23
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DeBose-Scarlett EM, Sullivan BA. Genomic and Epigenetic Foundations of Neocentromere Formation. Annu Rev Genet 2021; 55:331-348. [PMID: 34496611 DOI: 10.1146/annurev-genet-071719-020924] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Centromeres are essential to genome inheritance, serving as the site of kinetochore assembly and coordinating chromosome segregation during cell division. Abnormal centromere function is associated with birth defects, infertility, and cancer. Normally, centromeres are assembled and maintained at the same chromosomal location. However, ectopic centromeres form spontaneously at new genomic locations and contribute to genome instability and developmental defects as well as to acquired and congenital human disease. Studies in model organisms have suggested that certain regions of the genome, including pericentromeres, heterochromatin, and regions of open chromatin or active transcription, support neocentromere activation. However, there is no universal mechanism that explains neocentromere formation. This review focuses on recent technological and intellectual advances in neocentromere research and proposes future areas of study. Understanding neocentromere biology will provide a better perspective on chromosome and genome organization and functional context for information generated from the Human Genome Project, ENCODE, and other large genomic consortia. Expected final online publication date for the Annual Review of Genetics, Volume 55 is November 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Evon M DeBose-Scarlett
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina 27710, USA;
| | - Beth A Sullivan
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina 27710, USA;
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Dong Q, Yang J, Gao J, Li F. Recent insights into mechanisms preventing ectopic centromere formation. Open Biol 2021; 11:210189. [PMID: 34493071 PMCID: PMC8424319 DOI: 10.1098/rsob.210189] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The centromere is a specialized chromosomal structure essential for chromosome segregation. Centromere dysfunction leads to chromosome segregation errors and genome instability. In most eukaryotes, centromere identity is specified epigenetically by CENP-A, a centromere-specific histone H3 variant. CENP-A replaces histone H3 in centromeres, and nucleates the assembly of the kinetochore complex. Mislocalization of CENP-A to non-centromeric regions causes ectopic assembly of CENP-A chromatin, which has a devastating impact on chromosome segregation and has been linked to a variety of human cancers. How non-centromeric regions are protected from CENP-A misincorporation in normal cells is largely unexplored. Here, we review the most recent advances on the mechanisms underlying the prevention of ectopic centromere formation, and discuss the implications in human disease.
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Affiliation(s)
- Qianhua Dong
- Department of Biology, New York University, New York, NY 10003-6688, USA
| | - Jinpu Yang
- Department of Biology, New York University, New York, NY 10003-6688, USA
| | - Jinxin Gao
- Department of Biology, New York University, New York, NY 10003-6688, USA
| | - Fei Li
- Department of Biology, New York University, New York, NY 10003-6688, USA
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25
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Schotanus K, Yadav V, Heitman J. Epigenetic dynamics of centromeres and neocentromeres in Cryptococcus deuterogattii. PLoS Genet 2021; 17:e1009743. [PMID: 34464380 PMCID: PMC8407549 DOI: 10.1371/journal.pgen.1009743] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 07/26/2021] [Indexed: 11/25/2022] Open
Abstract
Deletion of native centromeres in the human fungal pathogen Cryptococcus deuterogattii leads to neocentromere formation. Native centromeres span truncated transposable elements, while neocentromeres do not and instead span actively expressed genes. To explore the epigenetic organization of neocentromeres, we analyzed the distribution of the heterochromatic histone modification H3K9me2, 5mC DNA methylation and the euchromatin mark H3K4me2. Native centromeres are enriched for both H3K9me2 and 5mC DNA methylation marks and are devoid of H3K4me2, while neocentromeres do not exhibit any of these features. Neocentromeres in cen10Δ mutants are unstable and chromosome-chromosome fusions occur. After chromosome fusion, the neocentromere is inactivated and the native centromere of the chromosome fusion partner remains as the sole, active centromere. In the present study, the active centromere of a fused chromosome was deleted to investigate if epigenetic memory promoted the re-activation of the inactive neocentromere. Our results show that the inactive neocentromere is not re-activated and instead a novel neocentromere forms directly adjacent to the deleted centromere of the fused chromosome. To study the impact of transcription on centromere stability, the actively expressed URA5 gene was introduced into the CENP-A bound regions of a native centromere. The introduction of the URA5 gene led to a loss of CENP-A from the native centromere, and a neocentromere formed adjacent to the native centromere location. Remarkably, the inactive, native centromere remained enriched for heterochromatin, yet the integrated gene was expressed and devoid of H3K9me2. A cumulative analysis of multiple CENP-A distribution profiles revealed centromere drift in C. deuterogattii, a previously unreported phenomenon in fungi. The CENP-A-binding shifted within the ORF-free regions and showed a possible association with a truncated transposable element. Taken together, our findings reveal that neocentromeres in C. deuterogattii are highly unstable and are not marked with an epigenetic memory, distinguishing them from native centromeres. Linear eukaryotic chromosomes require a specific chromosomal region, the centromere, where the macromolecular kinetochore protein complex assembles. In most organisms, centromeres are located in gene-free, repeat-rich chromosomal regions and may or may not be associated with heterochromatic epigenetic marks. We report that the native centromeres of the human fungal pathogen Cryptococcus deuterogattii are enriched with heterochromatin marks. Deleting a centromere in C. deuterogattii results in formation of neocentromeres that span genes. In some cases, neocentromeres are unstable leading to chromosome-chromosome fusions and neocentromere inactivation. These neocentromeres, unlike native centromeres, lack any of the tested heterochromatic marks or any epigenetic memory. We also found that neocentromere formation can be triggered not only by deletion of the native centromere but also by disrupting its function via insertion of a gene. These results show that neocentromere dynamics in this fungal pathogen are unique among organisms studied so far. Our results also revealed key differences between epigenetics of native centromeres between C. deuterogattii and its sister species, C. neoformans. These finding provide an opportunity to test and study the evolution of centromeres, as well as neocentromeres, in this species complex and how it might contribute to their genome evolution.
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Affiliation(s)
- Klaas Schotanus
- Duke University Medical Center, Durham, North Carolina, United States of America
| | - Vikas Yadav
- Duke University Medical Center, Durham, North Carolina, United States of America
| | - Joseph Heitman
- Duke University Medical Center, Durham, North Carolina, United States of America
- * E-mail:
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Joshi A, Musicante MJ, Wheeler BS. Defining the consequences of endogenous genetic variation within a novel family of Schizosaccharomyces pombe heterochromatin nucleating sequences. G3 GENES|GENOMES|GENETICS 2021; 11:6291246. [PMID: 34849813 PMCID: PMC8496282 DOI: 10.1093/g3journal/jkab185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 05/20/2021] [Indexed: 11/13/2022]
Abstract
Centromeres are essential for genetic inheritance—they prevent aneuploidy by providing a physical link between DNA and chromosome segregation machinery. In many organisms, centromeres form at sites of repetitive DNAs that help establish the chromatin architecture required for centromere function. These repeats are often rapidly evolving and subject to homogenization, which causes the expansion of novel repeats and sequence turnover. Thus, centromere sequence varies between individuals and across species. This variation can affect centromere function. We utilized Schizosaccharomyces pombe to assess the relationship between centromere sequence and chromatin structure and determine how sensitive this relationship is to genetic variation. In S. pombe, nucleating sequences within centromere repeats recruit heterochromatin via multiple mechanisms, which include RNA-interference (RNAi) . Heterochromatin, in turn, contributes to centromere function through its participation in three essential processes; establishment of a kinetochore, cohesion of sister chromatids, and suppression of recombination. Here, we show that a centromere element containing RevCen, a target of the RNAi pathway, establishes heterochromatin and gene silencing when relocated to a chromosome arm. Within this RevCen-containing element (RCE), a highly conserved domain is necessary for full heterochromatin nucleation but cannot establish heterochromatin independently. We characterize the 10 unique RCEs in the S. pombe centromere assembly, which range from 60% to 99.6% identical, and show that all are sufficient to establish heterochromatin. These data affirm the importance of centromere repeats in establishing heterochromatin and suggest there is flexibility within the sequences that mediate this process. Such flexibility may preserve centromere function despite the rapid evolution of centromere repeats.
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Affiliation(s)
- Arati Joshi
- Department of Biology, Rhodes College, Memphis, TN 38112, USA
| | | | - Bayly S Wheeler
- Department of Biology, Rhodes College, Memphis, TN 38112, USA
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27
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Pobiega S, Alibert O, Marcand S. A new assay capturing chromosome fusions shows a protection trade-off at telomeres and NHEJ vulnerability to low-density ionizing radiation. Nucleic Acids Res 2021; 49:6817-6831. [PMID: 34125900 PMCID: PMC8266670 DOI: 10.1093/nar/gkab502] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 03/31/2021] [Accepted: 05/27/2021] [Indexed: 11/14/2022] Open
Abstract
Chromosome fusions threaten genome integrity and promote cancer by engaging catastrophic mutational processes, namely chromosome breakage-fusion-bridge cycles and chromothripsis. Chromosome fusions are frequent in cells incurring telomere dysfunctions or those exposed to DNA breakage. Their occurrence and therefore their contribution to genome instability in unchallenged cells is unknown. To address this issue, we constructed a genetic assay able to capture and quantify rare chromosome fusions in budding yeast. This chromosome fusion capture (CFC) assay relies on the controlled inactivation of one centromere to rescue unstable dicentric chromosome fusions. It is sensitive enough to quantify the basal rate of end-to-end chromosome fusions occurring in wild-type cells. These fusions depend on canonical nonhomologous end joining (NHEJ). Our results show that chromosome end protection results from a trade-off at telomeres between positive effectors (Rif2, Sir4, telomerase) and a negative effector partially antagonizing them (Rif1). The CFC assay also captures NHEJ-dependent chromosome fusions induced by ionizing radiation. It provides evidence for chromosomal rearrangements stemming from a single photon-matter interaction.
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Affiliation(s)
- Sabrina Pobiega
- Université de Paris and Université Paris-Saclay, Inserm, CEA IBFJ/iRCM, UMR Stabilité Génétique Cellules Souches et Radiations, 92265 Fontenay-au-Roses, France
| | | | - Stéphane Marcand
- To whom correspondence should be addressed. Tel: +33 1 46 54 82 33;
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28
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Abstract
Murillo-Pineda and colleagues (2021. J. Cell Biol.https://doi.org/10.1083/jcb.202007210) use CRISPR-Cas9-based genetic engineering in human cells to induce a new functional centromere at a naive chromosomal site. Long-read DNA sequencing at the neocentromere provides firm evidence that centromere establishment is a truly epigenetic event.
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Affiliation(s)
| | - Elaine M. Dunleavy
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland
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29
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Murillo-Pineda M, Valente LP, Dumont M, Mata JF, Fachinetti D, Jansen LE. Induction of spontaneous human neocentromere formation and long-term maturation. J Cell Biol 2021; 220:e202007210. [PMID: 33443568 PMCID: PMC7812830 DOI: 10.1083/jcb.202007210] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 11/23/2020] [Accepted: 12/11/2020] [Indexed: 02/06/2023] Open
Abstract
Human centromeres form primarily on α-satellite DNA but sporadically arise de novo at naive ectopic loci, creating neocentromeres. Centromere inheritance is driven primarily by chromatin containing the histone H3 variant CENP-A. Here, we report a chromosome engineering system for neocentromere formation in human cells and characterize the first experimentally induced human neocentromere at a naive locus. The spontaneously formed neocentromere spans a gene-poor 100-kb domain enriched in histone H3 lysine 9 trimethylated (H3K9me3). Long-read sequencing revealed this neocentromere was formed by purely epigenetic means and assembly of a functional kinetochore correlated with CENP-A seeding, eviction of H3K9me3 and local accumulation of mitotic cohesin and RNA polymerase II. At formation, the young neocentromere showed markedly reduced chromosomal passenger complex (CPC) occupancy and poor sister chromatin cohesion. However, long-term tracking revealed increased CPC assembly and low-level transcription providing evidence for centromere maturation over time.
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Affiliation(s)
- Marina Murillo-Pineda
- Department of Biochemistry, University of Oxford, Oxford, UK
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | | | - Marie Dumont
- Institut Curie, Paris Sciences et Lettres, Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France
| | - João F. Mata
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Daniele Fachinetti
- Institut Curie, Paris Sciences et Lettres, Research University, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 144, Paris, France
| | - Lars E.T. Jansen
- Department of Biochemistry, University of Oxford, Oxford, UK
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
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30
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Vicars H, Karg T, Warecki B, Bast I, Sullivan W. Kinetochore-independent mechanisms of sister chromosome separation. PLoS Genet 2021; 17:e1009304. [PMID: 33513180 PMCID: PMC7886193 DOI: 10.1371/journal.pgen.1009304] [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: 08/11/2020] [Revised: 02/16/2021] [Accepted: 12/08/2020] [Indexed: 11/19/2022] Open
Abstract
Although kinetochores normally play a key role in sister chromatid separation and segregation, chromosome fragments lacking kinetochores (acentrics) can in some cases separate and segregate successfully. In Drosophila neuroblasts, acentric chromosomes undergo delayed, but otherwise normal sister separation, revealing the existence of kinetochore- independent mechanisms driving sister chromosome separation. Bulk cohesin removal from the acentric is not delayed, suggesting factors other than cohesin are responsible for the delay in acentric sister separation. In contrast to intact kinetochore-bearing chromosomes, we discovered that acentrics align parallel as well as perpendicular to the mitotic spindle. In addition, sister acentrics undergo unconventional patterns of separation. For example, rather than the simultaneous separation of sisters, acentrics oriented parallel to the spindle often slide past one another toward opposing poles. To identify the mechanisms driving acentric separation, we screened 117 RNAi gene knockdowns for synthetic lethality with acentric chromosome fragments. In addition to well-established DNA repair and checkpoint mutants, this candidate screen identified synthetic lethality with X-chromosome-derived acentric fragments in knockdowns of Greatwall (cell cycle kinase), EB1 (microtubule plus-end tracking protein), and Map205 (microtubule-stabilizing protein). Additional image-based screening revealed that reductions in Topoisomerase II levels disrupted sister acentric separation. Intriguingly, live imaging revealed that knockdowns of EB1, Map205, and Greatwall preferentially disrupted the sliding mode of sister acentric separation. Based on our analysis of EB1 localization and knockdown phenotypes, we propose that in the absence of a kinetochore, microtubule plus-end dynamics provide the force to resolve DNA catenations required for sister separation.
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Affiliation(s)
- Hannah Vicars
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, California, United States of America
| | - Travis Karg
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, California, United States of America
| | - Brandt Warecki
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, California, United States of America
| | - Ian Bast
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, California, United States of America
| | - William Sullivan
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, California, United States of America
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31
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Nuclear Envelope Proteins Modulating the Heterochromatin Formation and Functions in Fission Yeast. Cells 2020; 9:cells9081908. [PMID: 32824370 PMCID: PMC7464478 DOI: 10.3390/cells9081908] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/14/2020] [Accepted: 08/15/2020] [Indexed: 12/16/2022] Open
Abstract
The nuclear envelope (NE) consists of the inner and outer nuclear membranes (INM and ONM), and the nuclear pore complex (NPC), which penetrates the double membrane. ONM continues with the endoplasmic reticulum (ER). INM and NPC can interact with chromatin to regulate the genetic activities of the chromosome. Studies in the fission yeast Schizosaccharomyces pombe have contributed to understanding the molecular mechanisms underlying heterochromatin formation by the RNAi-mediated and histone deacetylase machineries. Recent studies have demonstrated that NE proteins modulate heterochromatin formation and functions through interactions with heterochromatic regions, including the pericentromeric and the sub-telomeric regions. In this review, we first introduce the molecular mechanisms underlying the heterochromatin formation and functions in fission yeast, and then summarize the NE proteins that play a role in anchoring heterochromatic regions and in modulating heterochromatin formation and functions, highlighting roles for a conserved INM protein, Lem2.
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32
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Warecki B, Sullivan W. Mechanisms driving acentric chromosome transmission. Chromosome Res 2020; 28:229-246. [PMID: 32712740 DOI: 10.1007/s10577-020-09636-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/16/2020] [Accepted: 07/19/2020] [Indexed: 02/07/2023]
Abstract
The kinetochore-microtubule association is a core, conserved event that drives chromosome transmission during mitosis. Failure to establish this association on even a single chromosome results in aneuploidy leading to cell death or the development of cancer. However, although many chromosomes lacking centromeres, termed acentrics, fail to segregate, studies in a number of systems reveal robust alternative mechanisms that can drive segregation and successful poleward transport of acentrics. In contrast to the canonical mechanism that relies on end-on microtubule attachments to kinetochores, mechanisms of acentric transmission largely fall into three categories: direct attachments to other chromosomes, kinetochore-independent lateral attachments to microtubules, and long-range tether-based attachments. Here, we review these "non-canonical" methods of acentric chromosome transmission. Just as the discovery and exploration of cell cycle checkpoints provided insight into both the origins of cancer and new therapies, identifying mechanisms and structures specifically involved in acentric segregation may have a significant impact on basic and applied cancer research.
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Affiliation(s)
- Brandt Warecki
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - William Sullivan
- Department of Molecular, Cell, and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, USA.
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33
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Guin K, Sreekumar L, Sanyal K. Implications of the Evolutionary Trajectory of Centromeres in the Fungal Kingdom. Annu Rev Microbiol 2020; 74:835-853. [PMID: 32706633 DOI: 10.1146/annurev-micro-011720-122512] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Chromosome segregation during the cell cycle is an evolutionarily conserved, fundamental biological process. Dynamic interaction between spindle microtubules and the kinetochore complex that assembles on centromere DNA is required for faithful chromosome segregation. The first artificial minichromosome was constructed by cloning the centromere DNA of the budding yeast Saccharomyces cerevisiae. Since then, centromeres have been identified in >60 fungal species. The DNA sequence and organization of the sequence elements are highly diverse across these fungal centromeres. In this article, we provide a comprehensive view of the evolution of fungal centromeres. Studies of this process facilitated the identification of factors influencing centromere specification, maintenance, and propagation through many generations. Additionally, we discuss the unique features and plasticity of centromeric chromatin and the involvement of centromeres in karyotype evolution. Finally, we discuss the implications of recurrent loss of RNA interference (RNAi) and/or heterochromatin components on the trajectory of the evolution of fungal centromeres and propose the centromere structure of the last common ancestor of three major fungal phyla-Ascomycota, Basidiomycota, and Mucoromycota.
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Affiliation(s)
- Krishnendu Guin
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560064, India; , ,
| | - Lakshmi Sreekumar
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560064, India; , ,
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka 560064, India; , ,
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34
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Leo L, Marchetti M, Giunta S, Fanti L. Epigenetics as an Evolutionary Tool for Centromere Flexibility. Genes (Basel) 2020; 11:genes11070809. [PMID: 32708654 PMCID: PMC7397245 DOI: 10.3390/genes11070809] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/11/2020] [Accepted: 07/13/2020] [Indexed: 12/31/2022] Open
Abstract
Centromeres are the complex structures responsible for the proper segregation of chromosomes during cell division. Structural or functional alterations of the centromere cause aneuploidies and other chromosomal aberrations that can induce cell death with consequences on health and survival of the organism as a whole. Because of their essential function in the cell, centromeres have evolved high flexibility and mechanisms of tolerance to preserve their function following stress, whether it is originating from within or outside the cell. Here, we review the main epigenetic mechanisms of centromeres’ adaptability to preserve their functional stability, with particular reference to neocentromeres and holocentromeres. The centromere position can shift in response to altered chromosome structures, but how and why neocentromeres appear in a given chromosome region are still open questions. Models of neocentromere formation developed during the last few years will be hereby discussed. Moreover, we will discuss the evolutionary significance of diffuse centromeres (holocentromeres) in organisms such as nematodes. Despite the differences in DNA sequences, protein composition and centromere size, all of these diverse centromere structures promote efficient chromosome segregation, balancing genome stability and adaptability, and ensuring faithful genome inheritance at each cellular generation.
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Affiliation(s)
- Laura Leo
- Istituto Pasteur Italia, Dipartimento di Biologia e Biotecnologie “Charles Darwin”, “Sapienza” University of Rome, 00185 Rome, Italy; (L.L.); (M.M.); (S.G.)
| | - Marcella Marchetti
- Istituto Pasteur Italia, Dipartimento di Biologia e Biotecnologie “Charles Darwin”, “Sapienza” University of Rome, 00185 Rome, Italy; (L.L.); (M.M.); (S.G.)
| | - Simona Giunta
- Istituto Pasteur Italia, Dipartimento di Biologia e Biotecnologie “Charles Darwin”, “Sapienza” University of Rome, 00185 Rome, Italy; (L.L.); (M.M.); (S.G.)
- Laboratory of Chromosome and Cell Biology, The Rockefeller University, New York, NY 10065, USA
| | - Laura Fanti
- Istituto Pasteur Italia, Dipartimento di Biologia e Biotecnologie “Charles Darwin”, “Sapienza” University of Rome, 00185 Rome, Italy; (L.L.); (M.M.); (S.G.)
- Correspondence:
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35
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Takayama Y. Identification of Genes Encoding CENP-A and Heterochromatin Protein 1 of Lipomyces starkeyi and Functional Analysis Using Schizosaccharomyces pombe. Genes (Basel) 2020; 11:genes11070769. [PMID: 32650514 PMCID: PMC7397231 DOI: 10.3390/genes11070769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 07/06/2020] [Accepted: 07/06/2020] [Indexed: 11/16/2022] Open
Abstract
Centromeres function as a platform for the assembly of multiple kinetochore proteins and are essential for chromosome segregation. An active centromere is characterized by the presence of a centromere-specific histone H3 variant, CENP-A. Faithful centromeric localization of CENP-A is supported by heterochromatin in almost all eukaryotes; however, heterochromatin proteins have been lost in most Saccharomycotina. Here, identification of CENP-A (CENP-AL.s.) and heterochromatin protein 1 (Lsw1) in a Saccharomycotina species, the oleaginous yeast Lipomyces starkeyi, is reported. To determine if these proteins are functional, the proteins in S. pombe, a species widely used to study centromeres, were ectopically expressed. CENP-AL.s. localizes to centromeres and can be replaced with S. pombe CENP-A, indicating that CENP-AL.s. is a functional centromere-specific protein. Lsw1 binds at heterochromatin regions, and chromatin binding is dependent on methylation of histone H3 at lysine 9. In other species, self-interaction of heterochromatin protein 1 is thought to cause folding of chromatin, triggering transcription repression and heterochromatin formation. Consistent with this, it was found that Lsw1 can self-interact. L. starkeyi chromatin contains the methylation of histone H3 at lysine 9. These results indicated that L. starkeyi has a primitive heterochromatin structure and is an attractive model for analysis of centromere heterochromatin evolution.
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Affiliation(s)
- Yuko Takayama
- Department of Biosciences, School of Science and Engineering, Teikyo University, 1-1 Toyosatodai, Utsunomiya, Tochigi 320–8551, Japan; ; Tel.: +81-28-627-7242
- Division of Integrated Science and Engineering, Graduate School of Science and Engineering, Teikyo University Graduate Schools, 1–1 Toyosatodai, Utsunomiya, Tochigi 320–8551, Japan
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36
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Wong CYY, Ling YH, Mak JKH, Zhu J, Yuen KWY. "Lessons from the extremes: Epigenetic and genetic regulation in point monocentromere and holocentromere establishment on artificial chromosomes". Exp Cell Res 2020; 390:111974. [PMID: 32222413 DOI: 10.1016/j.yexcr.2020.111974] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 03/16/2020] [Accepted: 03/18/2020] [Indexed: 02/08/2023]
Abstract
The formation of de novo centromeres on artificial chromosomes in humans (HACs) and fission yeast (SpYACs) has provided much insights to the epigenetic and genetic control on regional centromere establishment and maintenance. Similarly, the use of artificial chromosomes in point centromeric budding yeast Saccharomyces cerevisiae (ScYACs) and holocentric Caenorhabditis elegans (WACs) has revealed epigenetic regulation in the originally thought purely genetically-determined point centromeres and some centromeric DNA sequence features in holocentromeres, respectively. These relatively extreme and less characterized centromere organizations, on the endogenous chromosomes and artificial chromosomes, will be discussed and compared to the more well-studied regional centromere systems. This review will highlight some of the common epigenetic and genetic features in different centromere architectures, including the presence of the centromeric histone H3 variant, CENP-A or CenH3, centromeric and pericentric transcription, AT-richness and repetitiveness of centromeric DNA sequences.
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Affiliation(s)
- Charmaine Yan Yu Wong
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Yick Hin Ling
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jason Ka Ho Mak
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Jing Zhu
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong.
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37
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Schotanus K, Heitman J. Centromere deletion in Cryptococcus deuterogattii leads to neocentromere formation and chromosome fusions. eLife 2020; 9:56026. [PMID: 32310085 PMCID: PMC7188483 DOI: 10.7554/elife.56026] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 04/16/2020] [Indexed: 02/06/2023] Open
Abstract
The human fungal pathogen Cryptococcus deuterogattii is RNAi-deficient and lacks active transposons in its genome. C. deuterogattii has regional centromeres that contain only transposon relics. To investigate the impact of centromere loss on the C. deuterogattii genome, either centromere 9 or 10 was deleted. Deletion of either centromere resulted in neocentromere formation and interestingly, the genes covered by these neocentromeres maintained wild-type expression levels. In contrast to cen9∆ mutants, cen10∆ mutant strains exhibited growth defects and were aneuploid for chromosome 10. At an elevated growth temperature (37°C), the cen10∆ chromosome was found to have undergone fusion with another native chromosome in some isolates and this fusion restored wild-type growth. Following chromosomal fusion, the neocentromere was inactivated, and the native centromere of the fused chromosome served as the active centromere. The neocentromere formation and chromosomal fusion events observed in this study in C. deuterogattii may be similar to events that triggered genomic changes within the Cryptococcus/Kwoniella species complex and may contribute to speciation throughout the eukaryotic domain.
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Affiliation(s)
- Klaas Schotanus
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, United States
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, United States
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38
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Ohzeki JI, Otake K, Masumoto H. Human artificial chromosome: Chromatin assembly mechanisms and CENP-B. Exp Cell Res 2020; 389:111900. [PMID: 32044309 DOI: 10.1016/j.yexcr.2020.111900] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 12/12/2022]
Abstract
The centromere is a specialized chromosomal locus required for accurate chromosome segregation. Heterochromatin also assembles around centromere chromatin and forms a base that supports sister chromatid cohesion until anaphase begins. Both centromere chromatin and heterochromatin assemble on a centromeric DNA sequence, a highly repetitive sequence called alphoid DNA (α-satellite DNA) in humans. Alphoid DNA can form a de novo centromere and subsequent human artificial chromosome (HAC) when introduced into the human culture cells HT1080. HAC is maintained stably as a single chromosome independent of other human chromosomes. For de novo centromere assembly and HAC formation, the centromere protein CENP-B and its binding sites, CENP-B boxes, are required in the repeating units of alphoid DNA. CENP-B has multiple roles in de novo centromere chromatin assembly and stabilization and in heterochromatin formation upon alphoid DNA introduction into the cells. Here we review recent progress in human artificial chromosome construction and centromere/heterochromatin assembly and maintenance, focusing on the involvement of human centromere DNA and CENP-B protein.
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Affiliation(s)
- Jun-Ichirou Ohzeki
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, 292-0818, Japan
| | - Koichiro Otake
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, 292-0818, Japan
| | - Hiroshi Masumoto
- Laboratory of Chromosome Engineering, Department of Frontier Research and Development, Kazusa DNA Research Institute, 2-6-7 Kazusa-Kamatari, Kisarazu, 292-0818, Japan.
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39
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Murillo-Pineda M, Jansen LET. Genetics, epigenetics and back again: Lessons learned from neocentromeres. Exp Cell Res 2020; 389:111909. [PMID: 32068000 DOI: 10.1016/j.yexcr.2020.111909] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/04/2020] [Accepted: 02/10/2020] [Indexed: 12/12/2022]
Abstract
The duplication and segregation of the genome during cell division is crucial to maintain cell identity, development of organisms and tissue maintenance. Centromeres are at the basis of accurate chromosome segregation as they define the site of assembly of the kinetochore, a large complex of proteins that attaches to spindle microtubules driving chromosome movement during cell division. Here we summarize nearly 40 years of research focussed on centromere specification and the role of local cis elements in creating a stable centromere. Initial discoveries in budding yeast in the 1980s opened up the field and revealed essential DNA sequence elements that define centromere position and function. Further work in humans discovered a centromeric DNA sequence-specific binding protein and centromeric α-satellite DNA was found to have the capacity to seed centromeres de novo. Despite the early indication of genetic elements as drivers of centromere specification, the discovery in the nineties of neocentromeres that form on unrelated DNA sequences, shifted the focus to epigenetic mechanisms. While specific sequence elements appeared non-essential, the histone H3 variant CENP-A was identified as a crucial component in centromere specification. Neocentromeres, occurring naturally or induced experimentally, have become an insightful tool to understand the mechanisms for centromere specification and will be the focus of this review. They have helped to define the strong epigenetic chromatin-based component underlying centromere inheritance but also provide new opportunities to understand the enigmatic, yet crucial role that DNA sequence elements play in centromere function and inheritance.
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Affiliation(s)
| | - Lars E T Jansen
- Department of Biochemistry, University of Oxford, OX1 3QU, United Kingdom.
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40
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Hori T, Fukagawa T. Artificial generation of centromeres and kinetochores to understand their structure and function. Exp Cell Res 2020; 389:111898. [PMID: 32035949 DOI: 10.1016/j.yexcr.2020.111898] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 01/18/2020] [Accepted: 02/05/2020] [Indexed: 01/19/2023]
Abstract
The centromere is an essential genomic region that provides the surface to form the kinetochore, which binds to the spindle microtubes to mediate chromosome segregation during mitosis and meiosis. Centromeres of most organisms possess highly repetitive sequences, making it difficult to study these loci. However, an unusual centromere called a "neocentromere," which does not contain repetitive sequences, was discovered in a patient and can be generated experimentally. Recent advances in genome biology techniques allow us to analyze centromeric chromatin using neocentromeres. In addition to neocentromeres, artificial kinetochores have been generated on non-centromeric loci, using protein tethering systems. These are powerful tools to understand the mechanism of the centromere specification and kinetochore assembly. In this review, we introduce recent studies utilizing the neocentromeres and artificial kinetochores and discuss current problems in centromere biology.
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Affiliation(s)
- Tetsuya Hori
- 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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41
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Singh PP, Shukla M, White SA, Lafos M, Tong P, Auchynnikava T, Spanos C, Rappsilber J, Pidoux AL, Allshire RC. Hap2-Ino80-facilitated transcription promotes de novo establishment of CENP-A chromatin. Genes Dev 2020; 34:226-238. [PMID: 31919190 PMCID: PMC7000912 DOI: 10.1101/gad.332536.119] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/11/2019] [Indexed: 12/13/2022]
Abstract
Centromeres are maintained epigenetically by the presence of CENP-A, an evolutionarily conserved histone H3 variant, which directs kinetochore assembly and hence centromere function. To identify factors that promote assembly of CENP-A chromatin, we affinity-selected solubilized fission yeast CENP-ACnp1 chromatin. All subunits of the Ino80 complex were enriched, including the auxiliary subunit Hap2. Chromatin association of Hap2 is Ies4-dependent. In addition to a role in maintenance of CENP-ACnp1 chromatin integrity at endogenous centromeres, Hap2 is required for de novo assembly of CENP-ACnp1 chromatin on naïve centromere DNA and promotes H3 turnover on centromere regions and other loci prone to CENP-ACnp1 deposition. Prior to CENP-ACnp1 chromatin assembly, Hap2 facilitates transcription from centromere DNA. These analyses suggest that Hap2-Ino80 destabilizes H3 nucleosomes on centromere DNA through transcription-coupled histone H3 turnover, driving the replacement of resident H3 nucleosomes with CENP-ACnp1 nucleosomes. These inherent properties define centromere DNA by directing a program that mediates CENP-ACnp1 assembly on appropriate sequences.
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Affiliation(s)
- Puneet P. Singh
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Manu Shukla
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Sharon A. White
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Marcel Lafos
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Pin Tong
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Tatsiana Auchynnikava
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Christos Spanos
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom;,Bioanalytics, Institute of Biotechnology, Technische Universität Berlin, 13355 Berlin, Germany
| | - Alison L. Pidoux
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
| | - Robin C. Allshire
- Wellcome Centre for Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, United Kingdom
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42
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Sankaranarayanan SR, Ianiri G, Coelho MA, Reza MH, Thimmappa BC, Ganguly P, Vadnala RN, Sun S, Siddharthan R, Tellgren-Roth C, Dawson TL, Heitman J, Sanyal K. Loss of centromere function drives karyotype evolution in closely related Malassezia species. eLife 2020; 9:e53944. [PMID: 31958060 PMCID: PMC7025860 DOI: 10.7554/elife.53944] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
Genomic rearrangements associated with speciation often result in variation in chromosome number among closely related species. Malassezia species show variable karyotypes ranging between six and nine chromosomes. Here, we experimentally identified all eight centromeres in M. sympodialis as 3-5-kb long kinetochore-bound regions that span an AT-rich core and are depleted of the canonical histone H3. Centromeres of similar sequence features were identified as CENP-A-rich regions in Malassezia furfur, which has seven chromosomes, and histone H3 depleted regions in Malassezia slooffiae and Malassezia globosa with nine chromosomes each. Analysis of synteny conservation across centromeres with newly generated chromosome-level genome assemblies suggests two distinct mechanisms of chromosome number reduction from an inferred nine-chromosome ancestral state: (a) chromosome breakage followed by loss of centromere DNA and (b) centromere inactivation accompanied by changes in DNA sequence following chromosome-chromosome fusion. We propose that AT-rich centromeres drive karyotype diversity in the Malassezia species complex through breakage and inactivation.
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Affiliation(s)
- Sundar Ram Sankaranarayanan
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Giuseppe Ianiri
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Marco A Coelho
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Md Hashim Reza
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Bhagya C Thimmappa
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | - Promit Ganguly
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
| | | | - Sheng Sun
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | | | - Christian Tellgren-Roth
- National Genomics Infrastructure, Science for Life Laboratory, Department of Immunology, Genetics and Pathology, Uppsala UniversityUppsalaSweden
| | - Thomas L Dawson
- Skin Research Institute Singapore, Agency for Science, Technology and Research (A*STAR)SingaporeSingapore
- Department of Drug Discovery, Medical University of South Carolina, School of PharmacyCharlestonUnited States
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Kaustuv Sanyal
- Molecular Mycology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific ResearchBengaluruIndia
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43
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Achrem M, Szućko I, Kalinka A. The epigenetic regulation of centromeres and telomeres in plants and animals. COMPARATIVE CYTOGENETICS 2020; 14:265-311. [PMID: 32733650 PMCID: PMC7360632 DOI: 10.3897/compcytogen.v14i2.51895] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/18/2020] [Indexed: 05/10/2023]
Abstract
The centromere is a chromosomal region where the kinetochore is formed, which is the attachment point of spindle fibers. Thus, it is responsible for the correct chromosome segregation during cell division. Telomeres protect chromosome ends against enzymatic degradation and fusions, and localize chromosomes in the cell nucleus. For this reason, centromeres and telomeres are parts of each linear chromosome that are necessary for their proper functioning. More and more research results show that the identity and functions of these chromosomal regions are epigenetically determined. Telomeres and centromeres are both usually described as highly condensed heterochromatin regions. However, the epigenetic nature of centromeres and telomeres is unique, as epigenetic modifications characteristic of both eu- and heterochromatin have been found in these areas. This specificity allows for the proper functioning of both regions, thereby affecting chromosome homeostasis. This review focuses on demonstrating the role of epigenetic mechanisms in the functioning of centromeres and telomeres in plants and animals.
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Affiliation(s)
- Magdalena Achrem
- Institute of Biology, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
- Molecular Biology and Biotechnology Center, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
| | - Izabela Szućko
- Institute of Biology, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
- Molecular Biology and Biotechnology Center, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
| | - Anna Kalinka
- Institute of Biology, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
- Molecular Biology and Biotechnology Center, University of Szczecin, Szczecin, PolandUniversity of SzczecinSzczecinPoland
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44
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Ling YH, Lin Z, Yuen KWY. Genetic and epigenetic effects on centromere establishment. Chromosoma 2019; 129:1-24. [PMID: 31781852 DOI: 10.1007/s00412-019-00727-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 09/24/2019] [Accepted: 10/10/2019] [Indexed: 01/19/2023]
Abstract
Endogenous chromosomes contain centromeres to direct equal chromosomal segregation in mitosis and meiosis. The location and function of existing centromeres is usually maintained through cell cycles and generations. Recent studies have investigated how the centromere-specific histone H3 variant CENP-A is assembled and replenished after DNA replication to epigenetically propagate the centromere identity. However, existing centromeres occasionally become inactivated, with or without change in underlying DNA sequences, or lost after chromosomal rearrangements, resulting in acentric chromosomes. New centromeres, known as neocentromeres, may form on ectopic, non-centromeric chromosomal regions to rescue acentric chromosomes from being lost, or form dicentric chromosomes if the original centromere is still active. In addition, de novo centromeres can form after chromatinization of purified DNA that is exogenously introduced into cells. Here, we review the phenomena of naturally occurring and experimentally induced new centromeres and summarize the genetic (DNA sequence) and epigenetic features of these new centromeres. We compare the characteristics of new and native centromeres to understand whether there are different requirements for centromere establishment and propagation. Based on our understanding of the mechanisms of new centromere formation, we discuss the perspectives of developing more stably segregating human artificial chromosomes to facilitate gene delivery in therapeutics and research.
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Affiliation(s)
- Yick Hin Ling
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong
| | - Zhongyang Lin
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong
| | - Karen Wing Yee Yuen
- School of Biological Sciences, The University of Hong Kong, Kadoorie Biological Sciences Building, Pokfulam Road, Hong Kong.
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45
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Centromere repositioning causes inversion of meiosis and generates a reproductive barrier. Proc Natl Acad Sci U S A 2019; 116:21580-21591. [PMID: 31597736 PMCID: PMC6815110 DOI: 10.1073/pnas.1911745116] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Mutations in inner kinetochore components induce centromere repositioning without alteration in the centromeric DNA sequence, revealing a feedback mechanism underlying the high epigenetic stability of the centromere. This also provides a desirable experimental system to explore the functional significance of centromere positioning in meiosis. We discovered that in a heterozygotic meiosis, a repositioned centromere generates a reproductive barrier, suggesting a functional role of evolutionary new centromeres in speciation; furthermore, in a homozygotic meiosis, chromosomes carrying repositioned centromeres frequently undergo the 2 stages of meiotic segregation in an inverted order, demonstrating high flexibility in the meiotic process. The chromosomal position of each centromere is determined epigenetically and is highly stable, whereas incremental cases have supported the occurrence of centromere repositioning on an evolutionary time scale (evolutionary new centromeres, ENCs), which is thought to be important in speciation. The mechanisms underlying the high stability of centromeres and its functional significance largely remain an enigma. Here, in the fission yeast Schizosaccharomyces pombe, we identify a feedback mechanism: The kinetochore, whose assembly is guided by the centromere, in turn, enforces centromere stability. Upon going through meiosis, specific inner kinetochore mutations induce centromere repositioning—inactivation of the original centromere and formation of a new centromere elsewhere—in 1 of the 3 chromosomes at random. Repositioned centromeres reside asymmetrically in the pericentromeric regions and cells carrying them are competent in mitosis and homozygotic meiosis. However, when cells carrying a repositioned centromere are crossed with those carrying the original centromere, the progeny suffer severe lethality due to defects in meiotic chromosome segregation. Thus, repositioned centromeres constitute a reproductive barrier that could initiate genetic divergence between 2 populations with mismatched centromeres, documenting a functional role of ENCs in speciation. Surprisingly, homozygotic repositioned centromeres tend to undergo meiosis in an inverted order—that is, sister chromatids segregate first, and homologous chromosomes separate second—whereas the original centromeres on other chromosomes in the same cell undergo meiosis in the canonical order, revealing hidden flexibility in the perceived rigid process of meiosis.
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46
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Bracewell R, Chatla K, Nalley MJ, Bachtrog D. Dynamic turnover of centromeres drives karyotype evolution in Drosophila. eLife 2019; 8:e49002. [PMID: 31524597 PMCID: PMC6795482 DOI: 10.7554/elife.49002] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 09/12/2019] [Indexed: 12/21/2022] Open
Abstract
Centromeres are the basic unit for chromosome inheritance, but their evolutionary dynamics is poorly understood. We generate high-quality reference genomes for multiple Drosophila obscura group species to reconstruct karyotype evolution. All chromosomes in this lineage were ancestrally telocentric and the creation of metacentric chromosomes in some species was driven by de novo seeding of new centromeres at ancestrally gene-rich regions, independently of chromosomal rearrangements. The emergence of centromeres resulted in a drastic size increase due to repeat accumulation, and dozens of genes previously located in euchromatin are now embedded in pericentromeric heterochromatin. Metacentric chromosomes secondarily became telocentric in the pseudoobscura subgroup through centromere repositioning and a pericentric inversion. The former (peri)centric sequences left behind shrunk dramatically in size after their inactivation, yet contain remnants of their evolutionary past, including increased repeat-content and heterochromatic environment. Centromere movements are accompanied by rapid turnover of the major satellite DNA detected in (peri)centromeric regions.
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Affiliation(s)
- Ryan Bracewell
- Department of Integrative BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Kamalakar Chatla
- Department of Integrative BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Matthew J Nalley
- Department of Integrative BiologyUniversity of California, BerkeleyBerkeleyUnited States
| | - Doris Bachtrog
- Department of Integrative BiologyUniversity of California, BerkeleyBerkeleyUnited States
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47
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Tong P, Pidoux AL, Toda NRT, Ard R, Berger H, Shukla M, Torres-Garcia J, Müller CA, Nieduszynski CA, Allshire RC. Interspecies conservation of organisation and function between nonhomologous regional centromeres. Nat Commun 2019; 10:2343. [PMID: 31138803 PMCID: PMC6538654 DOI: 10.1038/s41467-019-09824-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 03/27/2019] [Indexed: 01/31/2023] Open
Abstract
Despite the conserved essential function of centromeres, centromeric DNA itself is not conserved. The histone-H3 variant, CENP-A, is the epigenetic mark that specifies centromere identity. Paradoxically, CENP-A normally assembles on particular sequences at specific genomic locations. To gain insight into the specification of complex centromeres, here we take an evolutionary approach, fully assembling genomes and centromeres of related fission yeasts. Centromere domain organization, but not sequence, is conserved between Schizosaccharomyces pombe, S. octosporus and S. cryophilus with a central CENP-ACnp1 domain flanked by heterochromatic outer-repeat regions. Conserved syntenic clusters of tRNA genes and 5S rRNA genes occur across the centromeres of S. octosporus and S. cryophilus, suggesting conserved function. Interestingly, nonhomologous centromere central-core sequences from S. octosporus and S. cryophilus are recognized in S. pombe, resulting in cross-species establishment of CENP-ACnp1 chromatin and functional kinetochores. Therefore, despite the lack of sequence conservation, Schizosaccharomyces centromere DNA possesses intrinsic conserved properties that promote assembly of CENP-A chromatin.
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Affiliation(s)
- Pin Tong
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK
| | - Alison L. Pidoux
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK
| | - Nicholas R. T. Toda
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK ,0000 0001 2203 0006grid.464101.6Present Address: UPMC CNRS, Roscoff Marine Station, Place Georges Teissier, 29680 Roscoff, France
| | - Ryan Ard
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK ,0000 0001 0674 042Xgrid.5254.6Present Address: Copenhagen Plant Science Centre, University of Copenhagen, Bülowsvej 34, 1870 Frederiksberg C, Denmark
| | - Harald Berger
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK ,0000 0001 2298 5320grid.5173.0Present Address: Symbiocyte, Universität für Bodenkultur Wien, University of Natural Resources and Life Sciences, 1180 Vienna, Austria
| | - Manu Shukla
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK
| | - Jesus Torres-Garcia
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK
| | - Carolin A. Müller
- 0000 0004 1936 8948grid.4991.5Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE UK
| | - Conrad A. Nieduszynski
- 0000 0004 1936 8948grid.4991.5Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford, OX1 3RE UK
| | - Robin C. Allshire
- 0000 0004 1936 7988grid.4305.2Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh, EH9 3BF UK
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48
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Shukla M, Tong P, White SA, Singh PP, Reid AM, Catania S, Pidoux AL, Allshire RC. Centromere DNA Destabilizes H3 Nucleosomes to Promote CENP-A Deposition during the Cell Cycle. Curr Biol 2018; 28:3924-3936.e4. [PMID: 30503616 PMCID: PMC6303189 DOI: 10.1016/j.cub.2018.10.049] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2017] [Revised: 09/12/2018] [Accepted: 10/22/2018] [Indexed: 12/31/2022]
Abstract
Active centromeres are defined by the presence of nucleosomes containing CENP-A, a histone H3 variant, which alone is sufficient to direct kinetochore assembly. Once assembled at a location, CENP-A chromatin and kinetochores are maintained at that location through a positive feedback loop where kinetochore proteins recruited by CENP-A promote deposition of new CENP-A following replication. Although CENP-A chromatin itself is a heritable entity, it is normally associated with specific sequences. Intrinsic properties of centromeric DNA may favor the assembly of CENP-A rather than H3 nucleosomes. Here we investigate histone dynamics on centromere DNA. We show that during S phase, histone H3 is deposited as a placeholder at fission yeast centromeres and is subsequently evicted in G2, when we detect deposition of the majority of new CENP-ACnp1. We also find that centromere DNA has an innate property of driving high rates of turnover of H3-containing nucleosomes, resulting in low nucleosome occupancy. When placed at an ectopic chromosomal location in the absence of any CENP-ACnp1 assembly, centromere DNA appears to retain its ability to impose S phase deposition and G2 eviction of H3, suggesting that features within centromere DNA program H3 dynamics. Because RNA polymerase II (RNAPII) occupancy on this centromere DNA coincides with H3 eviction in G2, we propose a model in which RNAPII-coupled chromatin remodeling promotes replacement of H3 with CENP-ACnp1 nucleosomes.
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Affiliation(s)
- Manu Shukla
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK.
| | - Pin Tong
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Sharon A White
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Puneet P Singh
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Angus M Reid
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Sandra Catania
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Alison L Pidoux
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Robin C Allshire
- Wellcome Centre for Cell Biology and Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3BF, UK.
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49
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Nishimura K, Komiya M, Hori T, Itoh T, Fukagawa T. 3D genomic architecture reveals that neocentromeres associate with heterochromatin regions. J Cell Biol 2018; 218:134-149. [PMID: 30396998 PMCID: PMC6314543 DOI: 10.1083/jcb.201805003] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 09/21/2018] [Accepted: 10/15/2018] [Indexed: 12/22/2022] Open
Abstract
Although centromeres usually associate with heterochromatic repetitive sequences, such repetitive sequences are not detected around neocentromeres. Nishimura et al. performed systematic 4C analysis of cells containing differently positioned neocentromeres and demonstrate that these neocentromeres commonly associate with distant heterochromatin-rich regions at the 3D level. The centromere is an important genomic locus for chromosomal segregation. Although the centromere is specified by sequence-independent epigenetic mechanisms in most organisms, it is usually composed of highly repetitive sequences, which associate with heterochromatin. We have previously generated various chicken DT40 cell lines containing differently positioned neocentromeres, which do not contain repetitive sequences and do not associate with heterochromatin. In this study, we performed systematic 4C analysis using three cell lines containing differently positioned neocentromeres to identify neocentromere-associated regions at the 3D level. This analysis reveals that these neocentromeres commonly associate with specific heterochromatin-rich regions, which were distantly located from neocentromeres. In addition, we demonstrate that centromeric chromatin adopts a compact structure, and centromere clustering also occurs in vertebrate interphase nuclei. Interestingly, the occurrence of centromere–heterochromatin associations depend on CENP-H, but not CENP-C. Our analyses provide an insight into understanding the 3D architecture of the genome, including the centromeres.
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Affiliation(s)
- Kohei Nishimura
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Masataka Komiya
- Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Tokyo, Japan
| | - Tetsuya Hori
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Takehiko Itoh
- Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Tokyo, Japan
| | - Tatsuo Fukagawa
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
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50
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Barra V, Fachinetti D. The dark side of centromeres: types, causes and consequences of structural abnormalities implicating centromeric DNA. Nat Commun 2018; 9:4340. [PMID: 30337534 PMCID: PMC6194107 DOI: 10.1038/s41467-018-06545-y] [Citation(s) in RCA: 164] [Impact Index Per Article: 27.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 09/06/2018] [Indexed: 12/18/2022] Open
Abstract
Centromeres are the chromosomal domains required to ensure faithful transmission of the genome during cell division. They have a central role in preventing aneuploidy, by orchestrating the assembly of several components required for chromosome separation. However, centromeres also adopt a complex structure that makes them susceptible to being sites of chromosome rearrangements. Therefore, preservation of centromere integrity is a difficult, but important task for the cell. In this review, we discuss how centromeres could potentially be a source of genome instability and how centromere aberrations and rearrangements are linked with human diseases such as cancer.
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Affiliation(s)
- V Barra
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, F-75005, Paris, France
| | - D Fachinetti
- Institut Curie, PSL Research University, CNRS, UMR 144, 26 rue d'Ulm, F-75005, Paris, France.
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