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Heuberger M, Koo DH, Ahmed HI, Tiwari VK, Abrouk M, Poland J, Krattinger SG, Wicker T. Evolution of Einkorn wheat centromeres is driven by the mutualistic interplay of two LTR retrotransposons. Mob DNA 2024; 15:16. [PMID: 39103880 DOI: 10.1186/s13100-024-00326-9] [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: 05/27/2024] [Accepted: 07/25/2024] [Indexed: 08/07/2024] Open
Abstract
BACKGROUND Centromere function is highly conserved across eukaryotes, but the underlying centromeric DNA sequences vary dramatically between species. Centromeres often contain a high proportion of repetitive DNA, such as tandem repeats and/or transposable elements (TEs). Einkorn wheat centromeres lack tandem repeat arrays and are instead composed mostly of the two long terminal repeat (LTR) retrotransposon families RLG_Cereba and RLG_Quinta which specifically insert in centromeres. However, it is poorly understood how these two TE families relate to each other and if and how they contribute to centromere function and evolution. RESULTS Based on conservation of diagnostic motifs (LTRs, integrase and primer binding site and polypurine-tract), we propose that RLG_Cereba and RLG_Quinta are a pair of autonomous and non-autonomous partners, in which the autonomous RLG_Cereba contributes all the proteins required for transposition, while the non-autonomous RLG_Quinta contributes GAG protein. Phylogenetic analysis of predicted GAG proteins showed that the RLG_Cereba lineage was present for at least 100 million years in monocotyledon plants. In contrast, RLG_Quinta evolved from RLG_Cereba between 28 and 35 million years ago in the common ancestor of oat and wheat. Interestingly, the integrase of RLG_Cereba is fused to a so-called CR-domain, which is hypothesized to guide the integrase to the functional centromere. Indeed, ChIP-seq data and TE population analysis show only the youngest subfamilies of RLG_Cereba and RLG_Quinta are found in the active centromeres. Importantly, the LTRs of RLG_Quinta and RLG_Cereba are strongly associated with the presence of the centromere-specific CENH3 histone variant. We hypothesize that the LTRs of RLG_Cereba and RLG_Quinta contribute to wheat centromere integrity by phasing and/or placing CENH3 nucleosomes, thus favoring their persistence in the competitive centromere-niche. CONCLUSION Our data show that RLG_Cereba cross-mobilizes the non-autonomous RLG_Quinta retrotransposons. New copies of both families are specifically integrated into functional centromeres presumably through direct binding of the integrase CR domain to CENH3 histone variants. The LTRs of newly inserted RLG_Cereba and RLG_Quinta elements, in turn, recruit and/or phase new CENH3 deposition. This mutualistic interplay between the two TE families and the plant host dynamically maintains wheat centromeres.
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Affiliation(s)
- Matthias Heuberger
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland
| | - Dal-Hoe Koo
- Wheat Genetics Resource Center and Department of Plant Pathology, Kansas State University, Manhattan, KS, 66506, USA
| | - Hanin Ibrahim Ahmed
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Centre d'Anthropobiologie et de Génomique de Toulouse (CAGT), Université Paul Sabatier, Toulouse, France
| | - Vijay K Tiwari
- Department of Plant Science and Landscape Architecture, University of Maryland, College Park, MD, 20724, USA
| | - Michael Abrouk
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Jesse Poland
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Simon G Krattinger
- Plant Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Thomas Wicker
- Department of Plant and Microbial Biology, University of Zurich, Zurich, Switzerland.
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Raipuria RK, Watts A, Sharma BB, Watts A, Bhattacharya R. Decoding allelic diversity, transcript variants and transcriptional complexity of CENH3 gene in Brassica oleracea var. botrytis. PROTOPLASMA 2023; 260:1149-1162. [PMID: 36705736 DOI: 10.1007/s00709-023-01837-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 01/07/2023] [Indexed: 06/07/2023]
Abstract
Histone proteins play a critical role in the primary organization of nucleosomes, which is the fundamental unit of chromatin. Among the five types of the histones, histone H3 has multiple variants, and the number differs among the species. Amongst histone H3 variants, centromeric histone H3 (CENH3) is crucial for centromere identification and proper chromosomal segregation during cell division. In the present study, we have identified 17 putative histone H3 genes of Brassica oleracea. Furthermore, we have done a detailed characterization of the CENH3 gene of B. oleracea. We showed that a single CENH3 gene exhibits allelic diversity with at least two alleles and alternative splicing pattern. Also, we have identified a CENH3 gene-specific co-dominant cleaved amplified polymorphic sequence marker SNP34(A/C) to distinguish CENH3 alleles and follow their expression in leaf and flower tissues. The gene structure analysis of the CENH3 gene revealed the conserved 5'-CAGCAG-3' sequence at the intron 3-exon 4 junction in B. oleracea, which serves as an alternative splicing site with one-codon (alanine) addition/deletion. However, this one-codon alternative splicing feature is not conserved in the CENH3 genes of wild allied Brassica species. Our finding suggests that transcriptional complexity and alternative splicing might play a key role in the transcriptional regulation and function of the CENH3 gene in B. oleracea. Altogether, data generated from the present study can serve as a primary information resource and can be used to engineer CENH3 gene towards developing haploid inducer lines in B. oleracea.
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Affiliation(s)
- Ritesh Kumar Raipuria
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi, 110012, India
| | - Anshul Watts
- ICAR-National Institute for Plant Biotechnology, Pusa Campus, New Delhi, 110012, India.
| | - Brij Bihari Sharma
- Division of Vegetable Science, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India
| | - Archana Watts
- Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, Pusa Campus, New Delhi, 110012, India
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Carraro M, Hendriks IA, Hammond CM, Solis-Mezarino V, Völker-Albert M, Elsborg JD, Weisser MB, Spanos C, Montoya G, Rappsilber J, Imhof A, Nielsen ML, Groth A. DAXX adds a de novo H3.3K9me3 deposition pathway to the histone chaperone network. Mol Cell 2023; 83:1075-1092.e9. [PMID: 36868228 PMCID: PMC10114496 DOI: 10.1016/j.molcel.2023.02.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 11/29/2022] [Accepted: 02/08/2023] [Indexed: 03/05/2023]
Abstract
A multitude of histone chaperones are required to support histones from their biosynthesis until DNA deposition. They cooperate through the formation of histone co-chaperone complexes, but the crosstalk between nucleosome assembly pathways remains enigmatic. Using exploratory interactomics, we define the interplay between human histone H3-H4 chaperones in the histone chaperone network. We identify previously uncharacterized histone-dependent complexes and predict the structure of the ASF1 and SPT2 co-chaperone complex, expanding the role of ASF1 in histone dynamics. We show that DAXX provides a unique functionality to the histone chaperone network, recruiting histone methyltransferases to promote H3K9me3 catalysis on new histone H3.3-H4 prior to deposition onto DNA. Hereby, DAXX provides a molecular mechanism for de novo H3K9me3 deposition and heterochromatin assembly. Collectively, our findings provide a framework for understanding how cells orchestrate histone supply and employ targeted deposition of modified histones to underpin specialized chromatin states.
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Affiliation(s)
- Massimo Carraro
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ivo A Hendriks
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Colin M Hammond
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | | | | | - Jonas D Elsborg
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Melanie B Weisser
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Christos Spanos
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK; Technische Universität Berlin, Chair of Bioanalytics, Berlin, Germany
| | - Guillermo Montoya
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Juri Rappsilber
- Wellcome Centre for Cell Biology, University of Edinburgh, Edinburgh, UK; Technische Universität Berlin, Chair of Bioanalytics, Berlin, Germany
| | - Axel Imhof
- EpiQMAx GmbH, Planegg, Germany; Faculty of Medicine, Biomedical Center, Protein Analysis Unit, Ludwig-Maximilians-Universität München, Planegg-Martinsried, Germany
| | - Michael L Nielsen
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Anja Groth
- Novo Nordisk Foundation Center for Protein Research (CPR), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark; Biotech Research and Innovation Centre (BRIC), Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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Li L, Yuan Q, Chu YM, Jiang HY, Zhao JH, Su Q, Huo DQ, Zhang XF. Advances in holliday junction recognition protein (HJURP): Structure, molecular functions, and roles in cancer. Front Cell Dev Biol 2023; 11:1106638. [PMID: 37025176 PMCID: PMC10070699 DOI: 10.3389/fcell.2023.1106638] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 03/13/2023] [Indexed: 04/08/2023] Open
Abstract
Oncogenes are increasingly recognized as important factors in the development and progression of cancer. Holliday Junction Recognition Protein (HJURP) is a highly specialized mitogenic protein that is a chaperone protein of histone H3. The HJURP gene is located on chromosome 2q37.1 and is involved in nucleosome composition in the mitotic region, forming a three-dimensional crystal structure with Centromere Protein A (CENP-A) and the histone 4 complex. HJURP is involved in the recruitment and assembly of centromere and kinetochore and plays a key role in stabilizing the chromosome structure of tumor cells, and its dysfunction may contribute to tumorigenesis. In the available studies HJURP is upregulated in a variety of cancer tissues and cancer cell lines and is involved in tumor proliferation, invasion, metastasis and immune response. In an in vivo model, overexpression of HJURP in most cancer cell lines promotes cell proliferation and invasiveness, reduces susceptibility to apoptosis, and promotes tumor growth. In addition, upregulation of HJURP was associated with poorer prognosis in a variety of cancers. These properties suggest that HJURP may be a possible target for the treatment of certain cancers. Various studies targeting HJURP as a prognostic and therapeutic target for cancer are gradually attracting interest and attention. This paper reviews the functional and molecular mechanisms of HJURP in a variety of tumor types with the aim of providing new targets for future cancer therapy.
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Affiliation(s)
- Lin Li
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, China
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
| | - Qiang Yuan
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
- School of Pharmacy, North Sichuan Medical College, Nanchong, China
| | - Yue-Ming Chu
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
- School of Pharmacy, North Sichuan Medical College, Nanchong, China
| | - Hang-Yu Jiang
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
- School of Pharmacy, North Sichuan Medical College, Nanchong, China
| | - Ju-Hua Zhao
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
| | - Qiang Su
- Institute of Tissue Engineering and Stem Cells, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
- Nanchong Key Laboratory of Individualized Drug Therapy, Nanchong, China
| | - Dan-Qun Huo
- Key Laboratory for Biorheological Science and Technology of Ministry of Education, Bioengineering College of Chongqing University, Chongqing, China
- *Correspondence: Dan-Qun Huo, ; Xiao-Fen Zhang,
| | - Xiao-Fen Zhang
- Department of Pharmacy, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, China
- *Correspondence: Dan-Qun Huo, ; Xiao-Fen Zhang,
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5
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Nunez-Vazquez R, Desvoyes B, Gutierrez C. Histone variants and modifications during abiotic stress response. FRONTIERS IN PLANT SCIENCE 2022; 13:984702. [PMID: 36589114 PMCID: PMC9797984 DOI: 10.3389/fpls.2022.984702] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 09/28/2022] [Indexed: 06/17/2023]
Abstract
Plants have developed multiple mechanisms as an adaptive response to abiotic stresses, such as salinity, drought, heat, cold, and oxidative stress. Understanding these regulatory networks is critical for coping with the negative impact of abiotic stress on crop productivity worldwide and, eventually, for the rational design of strategies to improve plant performance. Plant alterations upon stress are driven by changes in transcriptional regulation, which rely on locus-specific changes in chromatin accessibility. This process encompasses post-translational modifications of histone proteins that alter the DNA-histones binding, the exchange of canonical histones by variants that modify chromatin conformation, and DNA methylation, which has an implication in the silencing and activation of hypervariable genes. Here, we review the current understanding of the role of the major epigenetic modifications during the abiotic stress response and discuss the intricate relationship among them.
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6
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Borg M, Jiang D, Berger F. Histone variants take center stage in shaping the epigenome. CURRENT OPINION IN PLANT BIOLOGY 2021; 61:101991. [PMID: 33434757 DOI: 10.1016/j.pbi.2020.101991] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 12/09/2020] [Accepted: 12/17/2020] [Indexed: 05/28/2023]
Abstract
The dynamic properties of the nucleosome are central to genomic activity. Variants of the core histones that form the nucleosome play a pivotal role in modulating nucleosome structure and function. Despite often small differences in sequence, histone variants display remarkable diversity in genomic deposition and post-translational modification. Here, we summarize the roles played by histone variants in the establishment, maintenance and reprogramming of plant chromatin landscapes, with a focus on histone H3 variants. Deposition of replicative H3.1 during DNA replication controls epigenetic inheritance, while local replacement of H3.1 with H3.3 marks cells undergoing terminal differentiation. Deposition of specialized H3 variants in specific cell types is emerging as a novel mechanism of selective epigenetic reprogramming during the plant life cycle.
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Affiliation(s)
- Michael Borg
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | - Danhua Jiang
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Innovative Academy for Seed Design, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Frédéric Berger
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria.
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7
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Abstract
Nucleosome dynamics and properties are central to all forms of genomic activities. Among the core histones, H3 variants play a pivotal role in modulating nucleosome structure and function. Here, we focus on the impact of H3 variants on various facets of development. The deposition of the replicative H3 variant following DNA replication is essential for the transmission of the epigenomic information encoded in posttranscriptional modifications. Through this process, replicative H3 maintains cell fate while, in contrast, the replacement H3.3 variant opposes cell differentiation during early embryogenesis. In later steps of development, H3.3 and specialized H3 variants are emerging as new, important regulators of terminal cell differentiation, including neurons and gametes. The specific pathways that regulate the dynamics of the deposition of H3.3 are paramount during reprogramming events that drive zygotic activation and the initiation of a new cycle of development.
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Affiliation(s)
- Benjamin Loppin
- Laboratoire de Biologie et de Modélisation de la Cellule, CNRS UMR 5239, Ecole Normale Supérieure de Lyon, University of Lyon, F-69007 Lyon, France;
| | - Frédéric Berger
- Gregor Mendel Institute (GMI), Austrian Academy of Sciences, Vienna BioCenter (VBC), 1030 Vienna, Austria;
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8
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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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Lei B, Berger F. H2A Variants in Arabidopsis: Versatile Regulators of Genome Activity. PLANT COMMUNICATIONS 2020; 1:100015. [PMID: 33404536 PMCID: PMC7747964 DOI: 10.1016/j.xplc.2019.100015] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 11/13/2019] [Accepted: 12/11/2019] [Indexed: 05/16/2023]
Abstract
The eukaryotic nucleosome prevents access to the genome. Convergently evolving histone isoforms, also called histone variants, form diverse families that are enriched over distinct features of plant genomes. Among the diverse families of plant histone variants, H2A.Z exclusively marks genes. Here we review recent research progress on the genome-wide distribution patterns and deposition of H2A.Z in plants as well as its association with histone modifications and roles in plant chromatin regulation. We also discuss some hypotheses that explain the different findings about the roles of H2A.Z in plants.
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10
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Huang A, Kremser L, Schuler F, Wilflingseder D, Lindner H, Geley S, Lusser A. Phosphorylation of Drosophila CENP-A on serine 20 regulates protein turn-over and centromere-specific loading. Nucleic Acids Res 2019; 47:10754-10770. [PMID: 31535131 PMCID: PMC6847487 DOI: 10.1093/nar/gkz809] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 09/06/2019] [Accepted: 09/11/2019] [Indexed: 12/30/2022] Open
Abstract
Centromeres are specialized chromosomal regions epigenetically defined by the presence of the histone H3 variant CENP-A. CENP-A is required for kinetochore formation which is essential for chromosome segregation during mitosis. Spatial restriction of CENP-A to the centromere is tightly controlled. Its overexpression results in ectopic incorporation and the formation of potentially deleterious neocentromeres in yeast, flies and in various human cancers. While the contribution of posttranslational modifications of CENP-A to these processes has been studied in yeast and mammals to some extent, very little is known about Drosophila melanogaster. Here, we show that CENP-A is phosphorylated at serine 20 (S20) by casein kinase II and that in mitotic cells, the phosphorylated form is enriched on chromatin. Importantly, our results reveal that S20 phosphorylation regulates the turn-over of prenucleosomal CENP-A by the SCFPpa-proteasome pathway and that phosphorylation promotes removal of CENP-A from ectopic but not from centromeric sites in chromatin. We provide multiple lines of evidence for a crucial role of S20 phosphorylation in controlling restricted incorporation of CENP-A into centromeric chromatin in flies. Modulation of the phosphorylation state of S20 may provide the cells with a means to fine-tune CENP-A levels in order to prevent deleterious loading to extra-centromeric sites.
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Affiliation(s)
- Anming Huang
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Austria
| | - Leopold Kremser
- Institute of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Austria
| | - Fabian Schuler
- Institute of Developmental Immunology, Biocenter, Medical University of Innsbruck, Austria
| | - Doris Wilflingseder
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Austria
| | - Herbert Lindner
- Institute of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, Austria
| | - Stephan Geley
- Institute of Pathophysiology, Biocenter, Medical University of Innsbruck, Austria
| | - Alexandra Lusser
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, Austria
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11
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Sato H, Wu B, Delahaye F, Singer RH, Greally JM. Retargeting of macroH2A following mitosis to cytogenetic-scale heterochromatic domains. J Cell Biol 2019; 218:1810-1823. [PMID: 31110057 PMCID: PMC6548134 DOI: 10.1083/jcb.201811109] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/20/2019] [Accepted: 04/19/2019] [Indexed: 12/12/2022] Open
Abstract
How macroH2A, a histone variant involved in silencing gene expression, is inherited from parent to daughter cells is unclear. Using a combination of imaging, biochemical, and genomic approaches, Sato et al. describe how newly synthesized macroH2A is incorporated predominantly in the G1 phase of human mitosis, targeting heterochromatic regions. The heritability of chromatin states through cell division is a potential contributor to the epigenetic maintenance of cellular memory of prior states. The macroH2A histone variant has properties of a regulator of epigenetic cell memory, including roles controlling gene silencing and cell differentiation. Its mechanisms of regional genomic targeting and maintenance through cell division are unknown. Here, we combined in vivo imaging with biochemical and genomic approaches to show that human macroH2A is incorporated into chromatin in the G1 phase of the cell cycle following DNA replication. The newly incorporated macroH2A retargets the same large heterochromatic domains where macroH2A was already enriched in the previous cell cycle. It remains heterotypic, targeting individual nucleosomes that do not already contain a macroH2A molecule. The pattern observed resembles that of a new deposition of centromeric histone variants during the cell cycle, indicating mechanistic similarities for macrodomain-scale regulation of epigenetic properties of the cell.
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Affiliation(s)
- Hanae Sato
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY.,Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY
| | - Bin Wu
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY.,Gruss Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY
| | - Fabien Delahaye
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY.,Department of Obstetrics and Gynecology and Women's Health, Albert Einstein College of Medicine, Bronx, NY
| | - Robert H Singer
- Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY .,Gruss Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY.,Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY.,Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA
| | - John M Greally
- Center for Epigenomics and Department of Genetics, Albert Einstein College of Medicine, Bronx, NY
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12
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Schalch T, Steiner FA. Structure of centromere chromatin: from nucleosome to chromosomal architecture. Chromosoma 2017; 126:443-455. [PMID: 27858158 PMCID: PMC5509776 DOI: 10.1007/s00412-016-0620-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 12/14/2022]
Abstract
The centromere is essential for the segregation of chromosomes, as it serves as attachment site for microtubules to mediate chromosome segregation during mitosis and meiosis. In most organisms, the centromere is restricted to one chromosomal region that appears as primary constriction on the condensed chromosome and is partitioned into two chromatin domains: The centromere core is characterized by the centromere-specific histone H3 variant CENP-A (also called cenH3) and is required for specifying the centromere and for building the kinetochore complex during mitosis. This core region is generally flanked by pericentric heterochromatin, characterized by nucleosomes containing H3 methylated on lysine 9 (H3K9me) that are bound by heterochromatin proteins. During mitosis, these two domains together form a three-dimensional structure that exposes CENP-A-containing chromatin to the surface for interaction with the kinetochore and microtubules. At the same time, this structure supports the tension generated during the segregation of sister chromatids to opposite poles. In this review, we discuss recent insight into the characteristics of the centromere, from the specialized chromatin structures at the centromere core and the pericentromere to the three-dimensional organization of these regions that make up the functional centromere.
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Affiliation(s)
- Thomas Schalch
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
| | - Florian A Steiner
- Department of Molecular Biology, Sciences III, Institute of Genetics and Genomics of Geneva (iGE3), University of Geneva, Geneva, Switzerland.
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13
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Filipescu D, Naughtin M, Podsypanina K, Lejour V, Wilson L, Gurard-Levin ZA, Orsi GA, Simeonova I, Toufektchan E, Attardi LD, Toledo F, Almouzni G. Essential role for centromeric factors following p53 loss and oncogenic transformation. Genes Dev 2017; 31:463-480. [PMID: 28356341 PMCID: PMC5393061 DOI: 10.1101/gad.290924.116] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 02/24/2017] [Indexed: 11/25/2022]
Abstract
In mammals, centromere definition involves the histone variant CENP-A (centromere protein A), deposited by its chaperone, HJURP (Holliday junction recognition protein). Alterations in this process impair chromosome segregation and genome stability, which are also compromised by p53 inactivation in cancer. Here we found that CENP-A and HJURP are transcriptionally up-regulated in p53-null human tumors. Using an established mouse embryonic fibroblast (MEF) model combining p53 inactivation with E1A or HRas-V12 oncogene expression, we reproduced a similar up-regulation of HJURP and CENP-A. We delineate functional CDE/CHR motifs within the Hjurp and Cenpa promoters and demonstrate their roles in p53-mediated repression. To assess the importance of HJURP up-regulation in transformed murine and human cells, we used a CRISPR/Cas9 approach. Remarkably, depletion of HJURP leads to distinct outcomes depending on their p53 status. Functional p53 elicits a cell cycle arrest response, whereas, in p53-null transformed cells, the absence of arrest enables the loss of HJURP to induce severe aneuploidy and, ultimately, apoptotic cell death. We thus tested the impact of HJURP depletion in pre-established allograft tumors in mice and revealed a major block of tumor progression in vivo. We discuss a model in which an "epigenetic addiction" to the HJURP chaperone represents an Achilles' heel in p53-deficient transformed cells.
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Affiliation(s)
- Dan Filipescu
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Monica Naughtin
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Katrina Podsypanina
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Vincent Lejour
- Institut Curie, PSL Research University, UMR3244, CNRS, Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, UPMC Université Paris 06, UMR3244, CNRS, F-75005 Paris, France
| | - Laurence Wilson
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Zachary A Gurard-Levin
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Guillermo A Orsi
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Iva Simeonova
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
| | - Eleonore Toufektchan
- Institut Curie, PSL Research University, UMR3244, CNRS, Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, UPMC Université Paris 06, UMR3244, CNRS, F-75005 Paris, France
| | - Laura D Attardi
- Division of Radiation and Cancer Biology, Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305, USA
| | - Franck Toledo
- Institut Curie, PSL Research University, UMR3244, CNRS, Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, UPMC Université Paris 06, UMR3244, CNRS, F-75005 Paris, France
| | - Geneviève Almouzni
- Institut Curie, Paris Sciences et Lettres (PSL) Research University, UMR3664, Centre Nationnal de la Recherche Scientifique (CNRS), Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC) Université Paris 06, UMR3664, CNRS, F-75005 Paris, France
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14
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Abstract
Centromeric chromatin undergoes major changes in composition and architecture during each cell cycle. These changes in specialized chromatin facilitate kinetochore formation in mitosis to ensure proper chromosome segregation. Thus, proper orchestration of centromeric chromatin dynamics during interphase, including replication in S phase, is crucial. We provide the current view concerning the centromeric architecture associated with satellite repeat sequences in mammals and its dynamics during the cell cycle. We summarize the contributions of deposited histone variants and their chaperones, other centromeric components - including proteins and their post-translational modifications, and RNAs - and we link the expression and deposition timing of each component during the cell cycle. Because neocentromeres occur at ectopic sites, we highlight how cell cycle processes can go wrong, leading to neocentromere formation and potentially disease.
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Affiliation(s)
- Sebastian Müller
- Institut Curie, PSL Research University, CNRS, UMR3664, Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France.,Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR3664, F-75005 Paris, France
| | - Geneviève Almouzni
- Institut Curie, PSL Research University, CNRS, UMR3664, Equipe Labellisée Ligue contre le Cancer, F-75005 Paris, France.,Sorbonne Universités, UPMC Université Paris 06, CNRS, UMR3664, F-75005 Paris, France
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15
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Musacchio A, Desai A. A Molecular View of Kinetochore Assembly and Function. BIOLOGY 2017; 6:E5. [PMID: 28125021 PMCID: PMC5371998 DOI: 10.3390/biology6010005] [Citation(s) in RCA: 310] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 12/15/2022]
Abstract
Kinetochores are large protein assemblies that connect chromosomes to microtubules of the mitotic and meiotic spindles in order to distribute the replicated genome from a mother cell to its daughters. Kinetochores also control feedback mechanisms responsible for the correction of incorrect microtubule attachments, and for the coordination of chromosome attachment with cell cycle progression. Finally, kinetochores contribute to their own preservation, across generations, at the specific chromosomal loci devoted to host them, the centromeres. They achieve this in most species by exploiting an epigenetic, DNA-sequence-independent mechanism; notable exceptions are budding yeasts where a specific sequence is associated with centromere function. In the last 15 years, extensive progress in the elucidation of the composition of the kinetochore and the identification of various physical and functional modules within its substructure has led to a much deeper molecular understanding of kinetochore organization and the origins of its functional output. Here, we provide a broad summary of this progress, focusing primarily on kinetochores of humans and budding yeast, while highlighting work from other models, and present important unresolved questions for future studies.
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Affiliation(s)
- Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn Straße 11, Dortmund 44227, Germany.
- Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Essen 45117, Germany.
| | - Arshad Desai
- Ludwig Institute for Cancer Research, La Jolla, CA 92093, USA.
- Department of Cellular & Molecular Medicine, 9500 Gilman Dr., La Jolla, CA 92093, USA.
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16
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Hammond CM, Strømme CB, Huang H, Patel DJ, Groth A. Histone chaperone networks shaping chromatin function. Nat Rev Mol Cell Biol 2017; 18:141-158. [PMID: 28053344 DOI: 10.1038/nrm.2016.159] [Citation(s) in RCA: 347] [Impact Index Per Article: 49.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The association of histones with specific chaperone complexes is important for their folding, oligomerization, post-translational modification, nuclear import, stability, assembly and genomic localization. In this way, the chaperoning of soluble histones is a key determinant of histone availability and fate, which affects all chromosomal processes, including gene expression, chromosome segregation and genome replication and repair. Here, we review the distinct structural and functional properties of the expanding network of histone chaperones. We emphasize how chaperones cooperate in the histone chaperone network and via co-chaperone complexes to match histone supply with demand, thereby promoting proper nucleosome assembly and maintaining epigenetic information by recycling modified histones evicted from chromatin.
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Affiliation(s)
- Colin M Hammond
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Caroline B Strømme
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
| | - Hongda Huang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Anja Groth
- Biotech Research and Innovation Centre (BRIC) and Centre for Epigenetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen DK-2200, Denmark
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17
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Evolutionary Lessons from Species with Unique Kinetochores. CENTROMERES AND KINETOCHORES 2017; 56:111-138. [DOI: 10.1007/978-3-319-58592-5_5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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18
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Skin-Specific Deletion of Mis18α Impedes Proliferation and Stratification of Epidermal Keratinocytes. J Invest Dermatol 2016; 137:414-421. [PMID: 27670610 DOI: 10.1016/j.jid.2016.09.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2016] [Revised: 07/27/2016] [Accepted: 09/02/2016] [Indexed: 11/21/2022]
Abstract
The Mis18 proteins (Mis18α, Mis18β, and M18BP1) are pivotal to the deposition of CENP-A at the centromere during cell cycle progression and are indispensable for embryonic development. Here, we show that Mis18α is critical for the proliferation of keratinocytes and stratification of the epidermis. Mice lacking Mis18α in the epidermis died shortly after birth, showing skin abnormalities like thin and translucent skin and defective skin barrier functions. The epidermis of newborn Mis18α-deficient mice lacked distinct stratification and mature hair follicles, with a reduction in the number of proliferating cells and increased cell death in the basal layer. Earlier expression of the Cre recombinase from keratin-14 promoter in the ventral region resulted in earlier keratinocyte death in the ventral part compared with the dorsal part in the absence of Mis18α, leading to more severe malformation of the ventral epidermal layers. As observed in Mis18α-deficient mouse keratinocytes, knockdown of Mis18α in HaCaT cells caused marked loss of centromeric CENP-A dots and chromosomal misalignment. Overall, we propose that Mis18α is important for epidermal cell proliferation and stratification, because it is required for the deposition of CENP-A at the centromeric nucleosomes.
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19
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Ccp1 Homodimer Mediates Chromatin Integrity by Antagonizing CENP-A Loading. Mol Cell 2016; 64:79-91. [PMID: 27666591 DOI: 10.1016/j.molcel.2016.08.022] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 05/24/2016] [Accepted: 08/16/2016] [Indexed: 12/26/2022]
Abstract
CENP-A is a centromere-specific histone 3 variant essential for centromere specification. CENP-A partially replaces canonical histone H3 at the centromeres. How the particular CENP-A/H3 ratio at centromeres is precisely maintained is unknown. It also remains unclear how CENP-A is excluded from non-centromeric chromatin. Here, we identify Ccp1, an uncharacterized NAP family protein in fission yeast that antagonizes CENP-A loading at both centromeric and non-centromeric regions. Like the CENP-A loading factor HJURP, Ccp1 interacts with CENP-A and is recruited to centromeres at the end of mitosis in a Mis16-dependent manner. These data indicate that factors with opposing CENP-A loading activities are recruited to centromeres. Furthermore, Ccp1 also cooperates with H2A.Z to evict CENP-A assembled in euchromatin. Structural analyses indicate that Ccp1 forms a homodimer that is required for its anti-CENP-A loading activity. Our study establishes mechanisms for maintenance of CENP-A homeostasis at centromeres and the prevention of ectopic assembly of centromeres.
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20
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Kwenda L, Collins CM, Dattoli AA, Dunleavy EM. Nucleolar activity and CENP-C regulate CENP-A and CAL1 availability for centromere assembly in meiosis. Development 2016; 143:1400-12. [PMID: 27095496 PMCID: PMC4852514 DOI: 10.1242/dev.130625] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 02/19/2016] [Indexed: 11/20/2022]
Abstract
The centromere-specific histone CENP-A is the key epigenetic determinant of centromere identity. Whereas most histones are removed from mature sperm, CENP-A is retained to mark paternal centromeres. In Drosophila males we show that the centromere assembly factors CAL1 and CENP-C are required for meiotic chromosome segregation, CENP-A assembly and maintenance on sperm, as well as fertility. In meiosis, CENP-A accumulates with CAL1 in nucleoli. Furthermore, we show that CENP-C normally limits the release of CAL1 and CENP-A from nucleoli for proper centromere assembly in meiotic prophase I. Finally, we show that RNA polymerase I transcription is required for efficient CENP-A assembly in meiosis, as well as centromere tethering to nucleoli. Summary: Novel roles are uncovered for centromere assembly factors CENP-C and CAL1 in meiotic chromosome segregation, CENP-A assembly and maintenance of sperm, as well as fertility in Drosophila males.
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Affiliation(s)
- Lucretia Kwenda
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland
| | - Caitriona M Collins
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland
| | - Anna A Dattoli
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland
| | - Elaine M Dunleavy
- Centre for Chromosome Biology, Biomedical Sciences, National University of Ireland Galway, Galway, Ireland
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21
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Kang Y, Wang J, Neff A, Kratzer S, Kimura H, Davis RE. Differential Chromosomal Localization of Centromeric Histone CENP-A Contributes to Nematode Programmed DNA Elimination. Cell Rep 2016; 16:2308-16. [PMID: 27545882 DOI: 10.1016/j.celrep.2016.07.079] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Revised: 06/13/2016] [Accepted: 07/27/2016] [Indexed: 02/08/2023] Open
Abstract
The stability of the genome is paramount to organisms. However, diverse eukaryotes carry out programmed DNA elimination in which portions or entire chromsomes are lost in early development or during sex determination. During early development of the parasitic nematode, Ascaris suum, 13% of the genome is eliminated. How different genomic segments are reproducibly retained or discarded is unknown. Here, we show that centromeric histone CENP-A localization plays a key role in this process. We show that Ascaris chromosomes are holocentric during germline mitoses, with CENP-A distributed along their length. Prior to DNA elimination in the four-cell embryo, CENP-A is significantly diminished in chromosome regions that will be lost. This leads to the absence of kinetochores and microtubule attachment sites necessary for chromosome segregation, resulting in loss of these regions upon mitosis. Our data suggest that changes in CENP-A localization specify which portions of chromosomes will be lost during programmed DNA elimination.
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Affiliation(s)
- Yuanyuan Kang
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Jianbin Wang
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Ashley Neff
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Stella Kratzer
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Hiroshi Kimura
- Department of Biological Sciences, Tokyo Institute of Technology, Tokyo 152-8550, Japan
| | - Richard E Davis
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO 80045, USA.
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22
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Drinnenberg IA, Henikoff S, Malik HS. Evolutionary Turnover of Kinetochore Proteins: A Ship of Theseus? Trends Cell Biol 2016; 26:498-510. [PMID: 26877204 PMCID: PMC4914419 DOI: 10.1016/j.tcb.2016.01.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2015] [Revised: 01/15/2016] [Accepted: 01/19/2016] [Indexed: 10/22/2022]
Abstract
The kinetochore is a multiprotein complex that mediates the attachment of a eukaryotic chromosome to the mitotic spindle. The protein composition of kinetochores is similar across species as divergent as yeast and human. However, recent findings have revealed an unexpected degree of compositional diversity in kinetochores. For example, kinetochore proteins that are essential in some species have been lost in others, whereas new kinetochore proteins have emerged in other lineages. Even in lineages with similar kinetochore composition, individual kinetochore proteins have functionally diverged to acquire either essential or redundant roles. Thus, despite functional conservation, the repertoire of kinetochore proteins has undergone recurrent evolutionary turnover.
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Affiliation(s)
- Ines A Drinnenberg
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Current address: Chromatin Dynamics Unit, UMR2664, Institut Curie, Paris, France.
| | - Steven Henikoff
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Harmit S Malik
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
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23
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Prendergast L, Müller S, Liu Y, Huang H, Dingli F, Loew D, Vassias I, Patel DJ, Sullivan KF, Almouzni G. The CENP-T/-W complex is a binding partner of the histone chaperone FACT. Genes Dev 2016; 30:1313-26. [PMID: 27284163 PMCID: PMC4911930 DOI: 10.1101/gad.275073.115] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 05/02/2016] [Indexed: 01/28/2023]
Abstract
Prendergast et al. identified Spt16 and SSRP1, subunits of the H2A–H2B histone chaperone FACT, as CENP-W-binding partners through a proteomic screen. They developed a model in which the FACT chaperone stabilizes the soluble CENP-T/-W complex in the cell and promotes dynamics of exchange, enabling CENP-T/-W deposition at centromeres. The CENP-T/-W histone fold complex, as an integral part of the inner kinetochore, is essential for building a proper kinetochore at the centromere in order to direct chromosome segregation during mitosis. Notably, CENP-T/-W is not inherited at centromeres, and new deposition is absolutely required at each cell cycle for kinetochore function. However, the mechanisms underlying this new deposition of CENP-T/-W at centromeres are unclear. Here, we found that CENP-T deposition at centromeres is uncoupled from DNA synthesis. We identified Spt16 and SSRP1, subunits of the H2A–H2B histone chaperone facilitates chromatin transcription (FACT), as CENP-W binding partners through a proteomic screen. We found that the C-terminal region of Spt16 binds specifically to the histone fold region of CENP-T/-W. Furthermore, depletion of Spt16 impairs CENP-T and CENP-W deposition at endogenous centromeres, and site-directed targeting of Spt16 alone is sufficient to ensure local de novo CENP-T accumulation. We propose a model in which the FACT chaperone stabilizes the soluble CENP-T/-W complex in the cell and promotes dynamics of exchange, enabling CENP-T/-W deposition at centromeres.
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Affiliation(s)
- Lisa Prendergast
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Sebastian Müller
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Yiwei Liu
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Hongda Huang
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Florent Dingli
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL (Paris Sciences et Lettres) Research University Centre de Recherche, Paris 75005, France
| | - Damarys Loew
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; Laboratoire de Spectrométrie de Masse Protéomique, Institut Curie, PSL (Paris Sciences et Lettres) Research University Centre de Recherche, Paris 75005, France
| | - Isabelle Vassias
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
| | - Dinshaw J Patel
- Structural Biology Program, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA
| | - Kevin F Sullivan
- Centre for Chromosome Biology, School of Natural Sciences, National University of Ireland, Galway, Ireland
| | - Geneviève Almouzni
- UMR3664, Centre National de la Recherche Scientifique, Institut Curie, PSL (Paris Sciences et Lettres) Research University, F-75005 Paris, France; UMR3664, Centre National de la Recherche Scientifique, University Pierre and Marie Curie Paris 06, Sorbonne Universités, F-75005 Paris, France
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24
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Pesenti ME, Weir JR, Musacchio A. Progress in the structural and functional characterization of kinetochores. Curr Opin Struct Biol 2016; 37:152-63. [PMID: 27039078 DOI: 10.1016/j.sbi.2016.03.003] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/10/2016] [Accepted: 03/10/2016] [Indexed: 10/22/2022]
Abstract
Kinetochores are macromolecular complexes built on a specialized chromatin domain called the centromere. Kinetochores provide a site of attachment for spindle microtubules during mitosis. They also control a cell cycle checkpoint, the spindle assembly checkpoint, which coordinates mitotic exit with the completion of chromosome alignment on the mitotic spindle. Correct kinetochore operation is therefore indispensable for accurate chromosome segregation. With multiple copies of at least 30 structural core subunits and a myriad of regulatory subunits, kinetochores are among the largest known macromolecular machines. Biochemical reconstitution and structural analysis, together with functional studies, are bringing to light the organizational principles of these complex and fascinating structures. We summarize recent work and identify a few challenges for future work.
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Affiliation(s)
- Marion E Pesenti
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - John R Weir
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany
| | - Andrea Musacchio
- Department of Mechanistic Cell Biology, Max Planck Institute of Molecular Physiology, Otto-Hahn-Straße 11, 44227 Dortmund, Germany; Centre for Medical Biotechnology, Faculty of Biology, University Duisburg-Essen, Universitätsstraße, 45141 Essen, Germany.
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25
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Hildebrand EM, Biggins S. Regulation of Budding Yeast CENP-A levels Prevents Misincorporation at Promoter Nucleosomes and Transcriptional Defects. PLoS Genet 2016; 12:e1005930. [PMID: 26982580 PMCID: PMC4794243 DOI: 10.1371/journal.pgen.1005930] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 02/22/2016] [Indexed: 01/08/2023] Open
Abstract
The exclusive localization of the histone H3 variant CENP-A to centromeres is essential for accurate chromosome segregation. Ubiquitin-mediated proteolysis helps to ensure that CENP-A does not mislocalize to euchromatin, which can lead to genomic instability. Consistent with this, overexpression of the budding yeast CENP-ACse4 is lethal in cells lacking Psh1, the E3 ubiquitin ligase that targets CENP-ACse4 for degradation. To identify additional mechanisms that prevent CENP-ACse4 misincorporation and lethality, we analyzed the genome-wide mislocalization pattern of overexpressed CENP-ACse4 in the presence and absence of Psh1 by chromatin immunoprecipitation followed by high throughput sequencing. We found that ectopic CENP-ACse4 is enriched at promoters that contain histone H2A.ZHtz1 nucleosomes, but that H2A.ZHtz1 is not required for CENP-ACse4 mislocalization. Instead, the INO80 complex, which removes H2A.ZHtz1 from nucleosomes, promotes the ectopic deposition of CENP-ACse4. Transcriptional profiling revealed gene expression changes in the psh1Δ cells overexpressing CENP-ACse4. The down-regulated genes are enriched for CENP-ACse4 mislocalization to promoters, while the up-regulated genes correlate with those that are also transcriptionally up-regulated in an htz1Δ strain. Together, these data show that regulating centromeric nucleosome localization is not only critical for maintaining centromere function, but also for ensuring accurate promoter function and transcriptional regulation. Chromosomes carry the genetic material in cells. When cells divide, each daughter cell must inherit a single copy of each chromosome. The centromere is the locus on each chromosome that ensures the equal distribution of chromosomes during cell division. One essential protein involved in this task is CENP-ACse4, which normally localizes exclusively to centromeres. Here, we investigated where CENP-ACse4 spreads in the genome when parts of its regulatory machinery are removed. We found that CENP-ACse4 becomes mislocalized to promoters, the region upstream of each gene that controls the activity of the gene. Consistent with this, the mislocalization of CENP-ACse4 to promoters leads to problems with gene activity. Our work shows that mislocalization of centromeric proteins can have effects beyond chromosome segregation defects, such as interfering with gene expression on chromosome arms.
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Affiliation(s)
- Erica M. Hildebrand
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Molecular and Cellular Biology Program, University of Washington, Seattle, Washington, United States of America
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- * E-mail:
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Britt AB, Kuppu S. Cenh3: An Emerging Player in Haploid Induction Technology. FRONTIERS IN PLANT SCIENCE 2016; 7:357. [PMID: 27148276 PMCID: PMC4828581 DOI: 10.3389/fpls.2016.00357] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/07/2016] [Indexed: 05/18/2023]
Abstract
True-breeding lines are required for the development and production of crop varieties. In a classical breeding approach these lines are obtained through inbreeding, and often 7-9 generations of inbreeding is performed to achieve the desired level of homozygosity, over a period of several years. In contrast, the chromosomes of haploids can be doubled to produce true-breeding lines in a single generation. Over the last century, scientists have developed a variety of techniques to induce haploids and doubled haploids, though these techniques apply only to particular crop varieties. Ravi and Chan (2010) discovered that haploids could be obtained in Arabidopsis through the manipulation of the centromere-specific histone 3 variant, CENH3. Their approach, which involved extensive modifications to a transgenic CENH3, held promise of being translated to crop species, and has been successfully employed in maize (see Kelliher et al., 2016). Refinements of this technology have since been developed which indicate that non-transgenic modifications to CENH3 will also induce haploids. The complementation of a cenh3 null by CENH3 from closely related plant species can result in plants that are fertile but haploid-inducing on crossing by CENH3 wt plants- suggesting that introgression of alien CENH3 may produce non-transgenic haploid inducers. Similarly, a remarkably wide variety of point mutations in CENH3, inducible by chemical agents, have recently been shown to result in haploid induction on crossing by wild-type CENH3 plants. These CENH3-variant plants grow normally, are fully fertile on self-pollination, and may be present in existing mutagenized collections.
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Boltengagen M, Huang A, Boltengagen A, Trixl L, Lindner H, Kremser L, Offterdinger M, Lusser A. A novel role for the histone acetyltransferase Hat1 in the CENP-A/CID assembly pathway in Drosophila melanogaster. Nucleic Acids Res 2015; 44:2145-59. [PMID: 26586808 PMCID: PMC4797270 DOI: 10.1093/nar/gkv1235] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 11/02/2015] [Indexed: 12/21/2022] Open
Abstract
The incorporation of CENP-A into centromeric chromatin is an essential prerequisite for kinetochore formation. Yet, the molecular mechanisms governing this process are surprisingly divergent in different organisms. While CENP-A loading mechanisms have been studied in some detail in mammals, there are still large gaps to our understanding of CENP-A/Cid loading pathways in Drosophila. Here, we report on the characterization and delineation of at least three different CENP-A preloading complexes in Drosophila. Two complexes contain the CENP-A chaperones CAL1, FACT and/or Caf1/Rbap48. Notably, we identified a novel complex consisting of the histone acetyltransferase Hat1, Caf1 and CENP-A/H4. We show that Hat1 is required for proper CENP-A loading into chromatin, since knock-down in S2 cells leads to reduced incorporation of newly synthesized CENP-A. In addition, we demonstrate that CENP-A/Cid interacts with the HAT1 complex via an N-terminal region, which is acetylated in cytoplasmic but not in nuclear CENP-A. Since Hat1 is not responsible for acetylation of CENP-A/Cid, these results suggest a histone acetyltransferase activity-independent escort function for Hat1. Thus, our results point toward intriguing analogies between the complex processing pathways of newly synthesized CENP-A and canonical histones.
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Affiliation(s)
- Mark Boltengagen
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Anming Huang
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Anastasiya Boltengagen
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Lukas Trixl
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Herbert Lindner
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Leopold Kremser
- Division of Clinical Biochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Martin Offterdinger
- Division of Neurobiochemistry, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Alexandra Lusser
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
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Mattiroli F, D'Arcy S, Luger K. The right place at the right time: chaperoning core histone variants. EMBO Rep 2015; 16:1454-66. [PMID: 26459557 DOI: 10.15252/embr.201540840] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/17/2015] [Indexed: 12/13/2022] Open
Abstract
Histone proteins dynamically regulate chromatin structure and epigenetic signaling to maintain cell homeostasis. These processes require controlled spatial and temporal deposition and eviction of histones by their dedicated chaperones. With the evolution of histone variants, a network of functionally specific histone chaperones has emerged. Molecular details of the determinants of chaperone specificity for different histone variants are only slowly being resolved. A complete understanding of these processes is essential to shed light on the genuine biological roles of histone variants, their chaperones, and their impact on chromatin dynamics.
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Affiliation(s)
- Francesca Mattiroli
- Department of Molecular and Radiobiological Sciences, Howard Hughes Medical Institute, Colorado State University, Fort Collins, CO, USA
| | - Sheena D'Arcy
- Department of Molecular and Radiobiological Sciences, Howard Hughes Medical Institute, Colorado State University, Fort Collins, CO, USA
| | - Karolin Luger
- Department of Molecular and Radiobiological Sciences, Howard Hughes Medical Institute, Colorado State University, Fort Collins, CO, USA
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Fachinetti D, Han JS, McMahon MA, Ly P, Abdullah A, Wong AJ, Cleveland DW. DNA Sequence-Specific Binding of CENP-B Enhances the Fidelity of Human Centromere Function. Dev Cell 2015; 33:314-27. [PMID: 25942623 DOI: 10.1016/j.devcel.2015.03.020] [Citation(s) in RCA: 179] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Revised: 02/09/2015] [Accepted: 03/25/2015] [Indexed: 12/31/2022]
Abstract
Human centromeres are specified by a stably inherited epigenetic mark that maintains centromere position and function through a two-step mechanism relying on self-templating centromeric chromatin assembled with the histone H3 variant CENP-A, followed by CENP-A-dependent nucleation of kinetochore assembly. Nevertheless, natural human centromeres are positioned within specific megabase chromosomal regions containing α-satellite DNA repeats, which contain binding sites for the DNA sequence-specific binding protein CENP-B. We now demonstrate that CENP-B directly binds both CENP-A's amino-terminal tail and CENP-C, a key nucleator of kinetochore assembly. DNA sequence-dependent binding of CENP-B within α-satellite repeats is required to stabilize optimal centromeric levels of CENP-C. Chromosomes bearing centromeres without bound CENP-B, including the human Y chromosome, are shown to mis-segregate in cells at rates several-fold higher than chromosomes with CENP-B-containing centromeres. These data demonstrate a DNA sequence-specific enhancement by CENP-B of the fidelity of epigenetically defined human centromere function.
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Affiliation(s)
- Daniele Fachinetti
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA.
| | - Joo Seok Han
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Moira A McMahon
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Peter Ly
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Amira Abdullah
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Alex J Wong
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA
| | - Don W Cleveland
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA 92093, USA.
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Fang J, Liu Y, Wei Y, Deng W, Yu Z, Huang L, Teng Y, Yao T, You Q, Ruan H, Chen P, Xu RM, Li G. Structural transitions of centromeric chromatin regulate the cell cycle-dependent recruitment of CENP-N. Genes Dev 2015; 29:1058-73. [PMID: 25943375 PMCID: PMC4441053 DOI: 10.1101/gad.259432.115] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 04/13/2015] [Indexed: 11/24/2022]
Abstract
Specific recognition of centromere-specific histone variant CENP-A-containing chromatin by CENP-N is an essential process in the assembly of the kinetochore complex at centromeres prior to mammalian cell division. However, the mechanisms of CENP-N recruitment to centromeres/kinetochores remain unknown. Here, we show that a CENP-A-specific RG loop (Arg80/Gly81) plays an essential and dual regulatory role in this process. The RG loop assists the formation of a compact "ladder-like" structure of CENP-A chromatin, concealing the loop and thus impairing its role in recruiting CENP-N. Upon G1/S-phase transition, however, centromeric chromatin switches from the compact to an open state, enabling the now exposed RG loop to recruit CENP-N prior to cell division. Our results provide the first insights into the mechanisms by which the recruitment of CENP-N is regulated by the structural transitions between compaction and relaxation of centromeric chromatin during the cell cycle.
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Affiliation(s)
- Junnan Fang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuting Liu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yun Wei
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Wenqiang Deng
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhouliang Yu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Li Huang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yan Teng
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Ting Yao
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qinglong You
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haihe Ruan
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Ping Chen
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Rui-Ming Xu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Guohong Li
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China;
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HJURP Involvement in De Novo CenH3CENP-A and CENP-C Recruitment. Cell Rep 2015; 11:22-32. [DOI: 10.1016/j.celrep.2015.03.013] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 02/04/2015] [Accepted: 03/03/2015] [Indexed: 11/18/2022] Open
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32
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Mouysset J, Gilberto S, Meier MG, Lampert F, Belwal M, Meraldi P, Peter M. CRL4(RBBP7) is required for efficient CENP-A deposition at centromeres. J Cell Sci 2015; 128:1732-45. [PMID: 25795299 DOI: 10.1242/jcs.162305] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Accepted: 03/13/2015] [Indexed: 12/15/2022] Open
Abstract
The mitotic spindle drives chromosome movement during mitosis and attaches to chromosomes at dedicated genomic loci named centromeres. Centromeres are epigenetically specified by their histone composition, namely the presence of the histone H3 variant CENP-A, which is regulated during the cell cycle by its dynamic expression and localization. Here, we combined biochemical methods and quantitative imaging approaches to investigate a new function of CUL4-RING E3 ubiquitin ligases (CRL4) in regulating CENP-A dynamics. We found that the core components CUL4 and DDB1 are required for centromeric loading of CENP-A, but do not influence CENP-A maintenance or pre-nucleosomal CENP-A levels. Interestingly, we identified RBBP7 as a substrate-specific CRL4 adaptor required for this process, in addition to its role in binding and stabilizing soluble CENP-A. Our data thus suggest that the CRL4 complex containing RBBP7 (CRL4(RBBP7)) might regulate mitosis by promoting ubiquitin-dependent loading of newly synthesized CENP-A during the G1 phase of the cell cycle.
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Affiliation(s)
- Julien Mouysset
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
| | - Samuel Gilberto
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
| | - Michelle G Meier
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland Department of Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Fabienne Lampert
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
| | - Mukta Belwal
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
| | - Patrick Meraldi
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland Department of Physiology and Metabolism, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Matthias Peter
- Department of Biology, Institute of Biochemistry, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
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Folco HD, Campbell CS, May KM, Espinoza CA, Oegema K, Hardwick KG, Grewal SIS, Desai A. The CENP-A N-tail confers epigenetic stability to centromeres via the CENP-T branch of the CCAN in fission yeast. Curr Biol 2015; 25:348-356. [PMID: 25619765 PMCID: PMC4318777 DOI: 10.1016/j.cub.2014.11.060] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 11/17/2014] [Accepted: 11/21/2014] [Indexed: 12/29/2022]
Abstract
In most eukaryotes, centromeres are defined epigenetically by presence of the histone H3 variant CENP-A [1-3]. CENP-A-containing chromatin recruits the constitutive centromere-associated network (CCAN) of proteins, which in turn directs assembly of the outer kinetochore to form microtubule attachments and ensure chromosome segregation fidelity [4-6]. Whereas the mechanisms that load CENP-A at centromeres are being elucidated, the functions of its divergent N-terminal tail remain enigmatic [7-12]. Here, we employ the well-studied fission yeast centromere [13-16] to investigate the function of the CENP-A (Cnp1) N-tail. We show that alteration of the N-tail does not affect Cnp1 loading at centromeres, outer kinetochore formation, or spindle checkpoint signaling but nevertheless elevates chromosome loss. N-tail mutants exhibited synthetic lethality with an altered centromeric DNA sequence, with rare survivors harboring chromosomal fusions in which the altered centromere was epigenetically inactivated. Elevated centromere inactivation was also observed for N-tail mutants with unaltered centromeric DNA sequences. N-tail mutants specifically reduced localization of the CCAN proteins Cnp20/CENP-T and Mis6/CENP-I, but not Cnp3/CENP-C. Overexpression of Cnp20/CENP-T suppressed defects in an N-tail mutant, suggesting a link between reduced CENP-T recruitment and the observed centromere inactivation phenotype. Thus, the Cnp1 N-tail promotes epigenetic stability of centromeres in fission yeast, at least in part via recruitment of the CENP-T branch of the CCAN.
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Affiliation(s)
- H Diego Folco
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Christopher S Campbell
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Karen M May
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Celso A Espinoza
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Karen Oegema
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kevin G Hardwick
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Shiv I S Grewal
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, NIH, Bethesda, MD 20892, USA
| | - Arshad Desai
- Ludwig Institute for Cancer Research, Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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Horard B, Loppin B. Histone storage and deposition in the early Drosophila embryo. Chromosoma 2015; 124:163-75. [PMID: 25563491 DOI: 10.1007/s00412-014-0504-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 12/18/2022]
Abstract
Drosophila development initiates with the formation of a diploid zygote followed by the rapid division of embryonic nuclei. This syncytial phase of development occurs almost entirely under maternal control and ends when the blastoderm embryo cellularizes and activates its zygotic genome. The biosynthesis and storage of histones in quantity sufficient for chromatin assembly of several thousands of genome copies represent a unique challenge for the developing embryo. In this article, we have reviewed our current understanding of the mechanisms involved in the production, storage, and deposition of histones in the fertilized egg and during the exponential amplification of cleavage nuclei.
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Affiliation(s)
- Béatrice Horard
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire-CNRS UMR5534, Université Claude Bernard Lyon 1, University of Lyon, 69100, Villeurbanne, France
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Dynamic Phosphorylation of CENP-A at Ser68 Orchestrates Its Cell-Cycle-Dependent Deposition at Centromeres. Dev Cell 2015; 32:68-81. [DOI: 10.1016/j.devcel.2014.11.030] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Revised: 10/14/2014] [Accepted: 11/19/2014] [Indexed: 11/23/2022]
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Filipescu D, Müller S, Almouzni G. Histone H3 Variants and Their Chaperones During Development and Disease: Contributing to Epigenetic Control. Annu Rev Cell Dev Biol 2014; 30:615-46. [DOI: 10.1146/annurev-cellbio-100913-013311] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Dan Filipescu
- Institut Curie, Centre de Recherche, Paris, F-75248 France; , ,
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Abstract
The centromere is a specific chromosomal locus that organizes the assembly of the kinetochore. It plays a fundamental role in accurate chromosome segregation. In most eukaryotic organisms, each chromosome contains a single centromere the position and function of which are epigenetically specified. Occasionally, centromeres form at ectopic loci, which can be detrimental to the cell. However, the mechanisms that protect the cell against ectopic centromeres (neocentromeres) remain poorly understood. Centromere protein-A (CENP-A), a centromere-specific histone 3 (H3) variant, is found in all centromeres and is indispensable for centromere function. Here we report that the overexpression of CENP-A(Cnp1) in fission yeast results in the assembly of CENP-A(Cnp1) at noncentromeric chromatin during mitosis and meiosis. The noncentromeric CENP-A preferentially assembles near heterochromatin and is capable of recruiting kinetochore components. Consistent with this, cells overexpressing CENP-A(Cnp1) exhibit severe chromosome missegregation and spindle microtubule disorganization. In addition, pulse induction of CENP-A(Cnp1) overexpression reveals that ectopic CENP-A chromatin can persist for multiple generations. Intriguingly, ectopic assembly of CENP-A(cnp1) is suppressed by overexpression of histone H3 or H4. Finally, we demonstrate that deletion of the N-terminal domain of CENP-A(cnp1) results in an increase in the number of ectopic CENP-A sites and provide evidence that the N-terminal domain of CENP-A prevents CENP-A assembly at ectopic loci via the ubiquitin-dependent proteolysis. These studies expand our current understanding of how noncentromeric chromatin is protected from mistakenly assembling CENP-A.
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38
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Gurard-Levin ZA, Almouzni G. Histone modifications and a choice of variant: a language that helps the genome express itself. F1000PRIME REPORTS 2014; 6:76. [PMID: 25343033 PMCID: PMC4166940 DOI: 10.12703/p6-76] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Covalent post-translational modifications on histones impact chromatin structure and function. Their misfunction, along with perturbations or mutations in genes that regulate their dynamic status, has been observed in several diseases. Thus, targeting histone modifications represents attractive opportunities for therapeutic intervention and biomarker discovery. The best approach to address this challenge is to paint a comprehensive picture integrating the growing number of modifications on individual residues and their combinatorial association, the corresponding modifying enzymes, and effector proteins that bind modifications. Furthermore, how they are imposed in a distinct manner during the cell cycle and on specific histone variants are important dimensions to consider. Firstly, this report highlights innovative technologies used to characterize histone modifications, and the corresponding enzymes and effector proteins. Secondly, we examine the recent progress made in understanding the dynamics and maintenance of histone modifications on distinct variants. We also discuss their roles as potential carriers of epigenetic information. Finally, we provide examples of initiatives to exploit histone modifications in cancer management, with the potential for new therapeutic opportunities.
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Affiliation(s)
- Zachary A. Gurard-Levin
- Institut Curie, Centre de RechercheParis, F-75248France
- CNRS, UMR3664Paris, F-75248France
- Équipe Labellisée Ligue contre le Cancer, UMR3664Paris, F-75248France
- UPMC, UMR3664Paris, F-75248France
- Sorbonne University, PSLParisFrance
| | - Geneviève Almouzni
- Institut Curie, Centre de RechercheParis, F-75248France
- CNRS, UMR3664Paris, F-75248France
- Équipe Labellisée Ligue contre le Cancer, UMR3664Paris, F-75248France
- UPMC, UMR3664Paris, F-75248France
- Sorbonne University, PSLParisFrance
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Müller S, Rodriguez R. G-quadruplex interacting small molecules and drugs: from bench toward bedside. Expert Rev Clin Pharmacol 2014; 7:663-79. [DOI: 10.1586/17512433.2014.945909] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Müller S, Montes de Oca R, Lacoste N, Dingli F, Loew D, Almouzni G. Phosphorylation and DNA binding of HJURP determine its centromeric recruitment and function in CenH3(CENP-A) loading. Cell Rep 2014; 8:190-203. [PMID: 25001279 DOI: 10.1016/j.celrep.2014.06.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/21/2014] [Accepted: 06/01/2014] [Indexed: 01/20/2023] Open
Abstract
Centromeres, epigenetically defined by the presence of the histone H3 variant CenH3, are essential for ensuring proper chromosome segregation. In mammals, centromeric CenH3(CENP-A) deposition requires its dedicated chaperone HJURP and occurs during telophase/early G1. We find that the cell-cycle-dependent recruitment of HJURP to centromeres depends on its timely phosphorylation controlled via cyclin-dependent kinases. A nonphosphorylatable HJURP mutant localizes prematurely to centromeres in S and G2 phase. This unregulated targeting causes a premature loading of CenH3(CENP-A) at centromeres, and cell-cycle delays ensue. Once recruited to centromeres, HJURP functions to promote CenH3(CENP-A) deposition by a mechanism involving a unique DNA-binding domain. With our findings, we propose a model wherein (1) the phosphorylation state of HJURP controls its centromeric recruitment in a cell-cycle-dependent manner, and (2) HJURP binding to DNA is a mechanistic determinant in CenH3(CENP-A) loading.
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Affiliation(s)
- Sebastian Müller
- Institut Curie, Centre de Recherche, Paris 75248, France; CNRS, UMR3664, Paris 75248, France; Equipe Labellisée Ligue contre le Cancer, UMR3664, Paris 75248, France; UPMC, UMR3664, Paris 75248, France; Sorbonne University, Paris 75005, France
| | - Rocio Montes de Oca
- Institut Curie, Centre de Recherche, Paris 75248, France; CNRS, UMR3664, Paris 75248, France; Equipe Labellisée Ligue contre le Cancer, UMR3664, Paris 75248, France; UPMC, UMR3664, Paris 75248, France; Sorbonne University, Paris 75005, France
| | - Nicolas Lacoste
- Institut Curie, Centre de Recherche, Paris 75248, France; CNRS, UMR3664, Paris 75248, France; Equipe Labellisée Ligue contre le Cancer, UMR3664, Paris 75248, France; UPMC, UMR3664, Paris 75248, France; Sorbonne University, Paris 75005, France
| | - Florent Dingli
- Institut Curie, Centre de Recherche, Paris 75248, France; Laboratory of Proteomic Mass Spectrometry, 75248 Paris Cedex 05, France
| | - Damarys Loew
- Institut Curie, Centre de Recherche, Paris 75248, France; Laboratory of Proteomic Mass Spectrometry, 75248 Paris Cedex 05, France
| | - Geneviève Almouzni
- Institut Curie, Centre de Recherche, Paris 75248, France; CNRS, UMR3664, Paris 75248, France; Equipe Labellisée Ligue contre le Cancer, UMR3664, Paris 75248, France; UPMC, UMR3664, Paris 75248, France; Sorbonne University, Paris 75005, France.
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Subramanian L, Toda NRT, Rappsilber J, Allshire RC. Eic1 links Mis18 with the CCAN/Mis6/Ctf19 complex to promote CENP-A assembly. Open Biol 2014; 4:140043. [PMID: 24789708 PMCID: PMC4043117 DOI: 10.1098/rsob.140043] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
CENP-A chromatin forms the foundation for kinetochore assembly. Replication-independent incorporation of CENP-A at centromeres depends on its chaperone HJURPScm3, and Mis18 in vertebrates and fission yeast. The recruitment of Mis18 and HJURPScm3 to centromeres is cell cycle regulated. Vertebrate Mis18 associates with Mis18BP1KNL2, which is critical for the recruitment of Mis18 and HJURPScm3. We identify two novel fission yeast Mis18-interacting proteins (Eic1 and Eic2), components of the Mis18 complex. Eic1 is essential to maintain Cnp1CENP-A at centromeres and is crucial for kinetochore integrity; Eic2 is dispensable. Eic1 also associates with Fta7CENP-Q/Okp1, Cnl2Nkp2 and Mal2CENP-O/Mcm21, components of the constitutive CCAN/Mis6/Ctf19 complex. No Mis18BP1KNL2 orthologue has been identified in fission yeast, consequently it remains unknown how the key Cnp1CENP-A loading factor Mis18 is recruited. Our findings suggest that Eic1 serves a function analogous to that of Mis18BP1KNL2, thus representing the functional counterpart of Mis18BP1KNL2 in fission yeast that connects with a module within the CCAN/Mis6/Ctf19 complex to allow the temporally regulated recruitment of the Mis18/Scm3HJURP Cnp1CENP-A loading factors. The novel interactions identified between CENP-A loading factors and the CCAN/Mis6/Ctf19 complex are likely to also contribute to CENP-A maintenance in other organisms.
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Affiliation(s)
- Lakxmi Subramanian
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh EH9 3JR, UK
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Akiyoshi B, Gull K. Discovery of unconventional kinetochores in kinetoplastids. Cell 2014; 156:1247-1258. [PMID: 24582333 PMCID: PMC3978658 DOI: 10.1016/j.cell.2014.01.049] [Citation(s) in RCA: 171] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 01/06/2014] [Accepted: 01/10/2014] [Indexed: 11/17/2022]
Abstract
The kinetochore is the macromolecular protein complex that directs chromosome segregation in eukaryotes. It has been widely assumed that the core kinetochore consists of proteins that are common to all eukaryotes. However, no conventional kinetochore components have been identified in any kinetoplastid genome, thus challenging this assumption of universality. Here, we report the identification of 19 kinetochore proteins (KKT1–19) in Trypanosoma brucei. The majority is conserved among kinetoplastids, but none of them has detectable homology to conventional kinetochore proteins. These proteins instead have a variety of features not found in conventional kinetochore proteins. We propose that kinetoplastids build kinetochores using a distinct set of proteins. These findings provide important insights into the longstanding problem of the position of the root of the eukaryotic tree of life. Conventional kinetochore proteins cannot be identified in any kinetoplastid genome 19 kinetochore proteins were identified in Trypanosoma brucei Kinetoplastids possess unconventional kinetochores This discovery supports the hypothesis that kinetoplastids branched very early
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Affiliation(s)
- Bungo Akiyoshi
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK; Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK.
| | - Keith Gull
- Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK
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Desvoyes B, Fernández-Marcos M, Sequeira-Mendes J, Otero S, Vergara Z, Gutierrez C. Looking at plant cell cycle from the chromatin window. FRONTIERS IN PLANT SCIENCE 2014; 5:369. [PMID: 25120553 PMCID: PMC4110626 DOI: 10.3389/fpls.2014.00369] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 07/11/2014] [Indexed: 05/03/2023]
Abstract
The cell cycle is defined by a series of complex events, finely coordinated through hormonal, developmental and environmental signals, which occur in a unidirectional manner and end up in producing two daughter cells. Accumulating evidence reveals that chromatin is not a static entity throughout the cell cycle. In fact, there are many changes that include nucleosome remodeling, histone modifications, deposition and exchange, among others. Interestingly, it is possible to correlate the occurrence of several of these chromatin-related events with specific processes necessary for cell cycle progression, e.g., licensing of DNA replication origins, the E2F-dependent transcriptional wave in G1, the activation of replication origins in S-phase, the G2-specific transcription of genes required for mitosis or the chromatin packaging occurring in mitosis. Therefore, an emerging view is that chromatin dynamics must be considered as an intrinsic part of cell cycle regulation. In this article, we review the main features of several key chromatin events that occur at defined times throughout the cell cycle and discuss whether they are actually controlling the transit through specific cell cycle stages.
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Affiliation(s)
| | | | | | | | | | - Crisanto Gutierrez
- *Correspondence: Crisanto Gutierrez, Centro de Biologia Molecular Severo Ochoa, Consejo Superior de Investigaciones Cientificas, Universidad Autónoma de Madrid, Nicolas Cabrera 1, Cantoblanco, Madrid 28049, Spain e-mail:
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