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Keller D, Stinus S, Umlauf D, Gourbeyre E, Biot E, Olivier N, Mahou P, Beaurepaire E, Andrey P, Crabbe L. Non-random spatial organization of telomeres varies during the cell cycle and requires LAP2 and BAF. iScience 2024; 27:109343. [PMID: 38510147 PMCID: PMC10951912 DOI: 10.1016/j.isci.2024.109343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/30/2023] [Accepted: 02/22/2024] [Indexed: 03/22/2024] Open
Abstract
Spatial genome organization within the nucleus influences major biological processes and is impacted by the configuration of linear chromosomes. Here, we applied 3D spatial statistics and modeling on high-resolution telomere and centromere 3D-structured illumination microscopy images in cancer cells. We found a multi-scale organization of telomeres that dynamically evolved from a mixed clustered-and-regular distribution in early G1 to a purely regular distribution as cells progressed through the cell cycle. In parallel, our analysis revealed two pools of peripheral and internal telomeres, the proportions of which were inverted during the cell cycle. We then conducted a targeted screen using MadID to identify the molecular pathways driving or maintaining telomere anchoring to the nuclear envelope observed in early G1. Lamina-associated polypeptide (LAP) proteins were found transiently localized to telomeres in anaphase, a stage where LAP2α initiates the reformation of the nuclear envelope, and impacted telomere redistribution in the next interphase together with their partner barrier-to-autointegration factor (BAF).
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Affiliation(s)
- Debora Keller
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
- Laboratory for Optics and Biosciences, École polytechnique, CNRS, INSERM, IP Paris, 91128 Palaiseau, France
| | - Sonia Stinus
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - David Umlauf
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Edith Gourbeyre
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
| | - Eric Biot
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Nicolas Olivier
- Laboratory for Optics and Biosciences, École polytechnique, CNRS, INSERM, IP Paris, 91128 Palaiseau, France
| | - Pierre Mahou
- Laboratory for Optics and Biosciences, École polytechnique, CNRS, INSERM, IP Paris, 91128 Palaiseau, France
| | - Emmanuel Beaurepaire
- Laboratory for Optics and Biosciences, École polytechnique, CNRS, INSERM, IP Paris, 91128 Palaiseau, France
| | - Philippe Andrey
- Université Paris-Saclay, INRAE, AgroParisTech, Institut Jean-Pierre Bourgin (IJPB), 78000 Versailles, France
| | - Laure Crabbe
- Molecular, Cellular and Developmental Biology Department (MCD), Centre de Biologie Intégrative (CBI), University of Toulouse, CNRS, UPS, 31062 Toulouse, France
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2
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Ito N, Sakamoto T, Oko Y, Sato H, Hanamata S, Sakamoto Y, Matsunaga S. Nuclear pore complex proteins are involved in centromere distribution. iScience 2024; 27:108855. [PMID: 38318384 PMCID: PMC10839643 DOI: 10.1016/j.isci.2024.108855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Revised: 11/28/2023] [Accepted: 01/05/2024] [Indexed: 02/07/2024] Open
Abstract
The subnuclear distribution of centromeres is cooperatively regulated by condensin II and the linker of nucleoskeleton and cytoskeleton (LINC) complex. However, other nuclear membrane structures and nuclear proteins are probably involved in centromere dynamics and distribution. Here, we focused on the nuclear pore complex (NPC), which is known to regulate gene expression, transcription memory, and chromatin structure in addition to transport between the cytoplasm and nucleoplasm. We report here that some nucleoporins (Nups), including Nup85, Nup133, CG1, Nup93b, and NUA, are involved in centromere scattering in Arabidopsis thaliana. In addition, the centromere dynamics after metaphase in nup mutants were found to be similar to that of the condensin II mutant. Furthermore, both biochemical and genetic approaches showed that the Nups interact with the LINC complex. These results suggest that Nups regulate centromere scattering cooperatively with condensin II and the LINC complex.
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Affiliation(s)
- Nanami Ito
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Takuya Sakamoto
- Department of Science, Faculty of Science, Kanagawa University, Yokohama, Kanagawa 221-8686, Japan
- Faculty of Science and Technology, Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Yuka Oko
- Faculty of Science and Technology, Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Hikaru Sato
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
| | - Shigeru Hanamata
- Department of Science, Faculty of Science, Kanagawa University, Yokohama, Kanagawa 221-8686, Japan
| | - Yuki Sakamoto
- Department of Biological Sciences, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Sachihiro Matsunaga
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Chiba 277-8562, Japan
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3
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Strachan J, Leidecker O, Spanos C, Le Coz C, Chapman E, Arsenijevic A, Zhang H, Zhao N, Spoel SH, Bayne EH. SUMOylation regulates Lem2 function in centromere clustering and silencing. J Cell Sci 2023; 136:jcs260868. [PMID: 37970674 PMCID: PMC10730020 DOI: 10.1242/jcs.260868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 11/07/2023] [Indexed: 11/17/2023] Open
Abstract
Regulation by the small modifier SUMO is heavily dependent on spatial control of enzymes that mediate the attachment and removal of SUMO on substrate proteins. Here, we show that in the fission yeast Schizosaccharomyces pombe, delocalisation of the SUMO protease Ulp1 from the nuclear envelope results in centromeric defects that can be attributed to hyper-SUMOylation at the nuclear periphery. Unexpectedly, we find that although this localised hyper-SUMOylation impairs centromeric silencing, it can also enhance centromere clustering. Moreover, both effects are at least partially dependent on SUMOylation of the inner nuclear membrane protein Lem2. Lem2 has previously been implicated in diverse biological processes, including the promotion of both centromere clustering and silencing, but how these distinct activities are coordinated was unclear; our observations suggest a model whereby SUMOylation serves as a regulatory switch, modulating Lem2 interactions with competing partner proteins to balance its roles in alternative pathways. Our findings also reveal a previously unappreciated role for SUMOylation in promoting centromere clustering.
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Affiliation(s)
- Joanna Strachan
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Orsolya Leidecker
- Max Planck Institute for Biology of Ageing, Joseph-Stelzmann-Strasse 9b, Cologne 50931, Germany
| | - Christos Spanos
- Wellcome Centre for Cell Biology, Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Clementine Le Coz
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Elliott Chapman
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Ana Arsenijevic
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Haidao Zhang
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Ning Zhao
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
| | - Steven H. Spoel
- Institute of Molecular Plant Sciences, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3BF, UK
| | - Elizabeth H. Bayne
- Institute of Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3FF, UK
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4
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Kumar P, Gholamalamdari O, Zhang Y, Zhang L, Vertii A, van Schaik T, Peric-Hupkes D, Sasaki T, Gilbert DM, van Steensel B, Ma J, Kaufman PD, Belmont AS. Nucleolus and centromere TSA-Seq reveals variable localization of heterochromatin in different cell types. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.29.564613. [PMID: 37961445 PMCID: PMC10634939 DOI: 10.1101/2023.10.29.564613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Genome differential positioning within interphase nuclei remains poorly explored. We extended and validated TSA-seq to map genomic regions near nucleoli and pericentric heterochromatin in four human cell lines. Our study confirmed that smaller chromosomes localize closer to nucleoli but further deconvolved this by revealing a preference for chromosome arms below 36-46 Mbp in length. We identified two lamina associated domain subsets through their differential nuclear lamina versus nucleolar positioning in different cell lines which showed distinctive patterns of DNA replication timing and gene expression across all cell lines. Unexpectedly, active, nuclear speckle-associated genomic regions were found near typically repressive nuclear compartments, which is attributable to the close proximity of nuclear speckles and nucleoli in some cell types, and association of centromeres with nuclear speckles in hESCs. Our study points to a more complex and variable nuclear genome organization than suggested by current models, as revealed by our TSA-seq methodology.
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5
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Sakamoto T, Matsunaga S. Chromatin dynamics and subnuclear gene positioning for transcriptional regulation. CURRENT OPINION IN PLANT BIOLOGY 2023; 75:102431. [PMID: 37562088 DOI: 10.1016/j.pbi.2023.102431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 07/02/2023] [Accepted: 07/03/2023] [Indexed: 08/12/2023]
Abstract
Plants have been found to exhibit diverse characteristics and functions of chromatin organization, showing both similarities and differences to animals. It is becoming clear how chromatin organization is linked to transcriptional regulation in response to environmental stresses. Regulation of specific chromatin positions in the nuclear space is important for transcription, and the mechanisms that enable such chromatin dynamics are gradually being unveiled. Genes move between subdomains responsible for transcriptional activation or suppression in the subnuclear space in a gene repositioning cycle. We propose a model of localized chromatin interaction in nuclear subdomains, in which the dynamics of local chromatin interactions have a more important impact on the regulation of gene expression than large-scale chromatin organization. In this mini-review, we highlight recent findings on chromatin dynamics, particularly involving transcriptional regulation, and discuss future directions in the study of chromatin organization in plants.
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Affiliation(s)
- Takuya Sakamoto
- Department of Science, Faculty of Science, Kanagawa University, 3-27-1 Rokkakubashi, Kanagawa-ku, Yokohama, Kanagawa 221-0802, Japan
| | - Sachihiro Matsunaga
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
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6
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Fujita Y, Pather SR, Ming GL, Song H. 3D spatial genome organization in the nervous system: From development and plasticity to disease. Neuron 2022; 110:2902-2915. [PMID: 35777365 PMCID: PMC9509413 DOI: 10.1016/j.neuron.2022.06.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 03/15/2022] [Accepted: 06/03/2022] [Indexed: 01/03/2023]
Abstract
Chromatin is organized into multiscale three-dimensional structures, including chromosome territories, A/B compartments, topologically associating domains, and chromatin loops. This hierarchically organized genomic architecture regulates gene transcription, which, in turn, is essential for various biological processes during brain development and adult plasticity. Here, we review different aspects of spatial genome organization and their functions in regulating gene expression in the nervous system, as well as their dysregulation in brain disorders. We also highlight new technologies to probe and manipulate chromatin architecture and discuss how investigating spatial genome organization can lead to a better understanding of the nervous system and associated disorders.
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Affiliation(s)
- Yuki Fujita
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Developmental Biology, Faculty of Medicine, Shimane University, Izumo City, Shimane 693-8501, Japan.
| | - Sarshan R Pather
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Cell and Molecular Biology Graduate Group, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Guo-Li Ming
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hongjun Song
- Department of Neuroscience, Mahoney Institute for Neurosciences, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; The Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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7
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Belmont AS. Nuclear Compartments: An Incomplete Primer to Nuclear Compartments, Bodies, and Genome Organization Relative to Nuclear Architecture. Cold Spring Harb Perspect Biol 2022; 14:a041268. [PMID: 34400557 PMCID: PMC9248822 DOI: 10.1101/cshperspect.a041268] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
This work reviews nuclear compartments, defined broadly to include distinct nuclear structures, bodies, and chromosome domains. It first summarizes original cytological observations before comparing concepts of nuclear compartments emerging from microscopy versus genomic approaches and then introducing new multiplexed imaging approaches that promise in the future to meld both approaches. I discuss how previous models of radial distribution of chromosomes or the binary division of the genome into A and B compartments are now being refined by the recognition of more complex nuclear compartmentalization. The poorly understood question of how these nuclear compartments are established and maintained is then discussed, including through the modern perspective of phase separation, before moving on to address possible functions of nuclear compartments, using the possible role of nuclear speckles in modulating gene expression as an example. Finally, the review concludes with a discussion of future questions for this field.
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Affiliation(s)
- Andrew S Belmont
- Department of Cell and Developmental Biology, University of Illinois, Urbana-Champaign, Urbana, Illinois 61801, USA
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8
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Jeffery D, Lochhead M, Almouzni G. CENP-A: A Histone H3 Variant with Key Roles in Centromere Architecture in Healthy and Diseased States. Results Probl Cell Differ 2022; 70:221-261. [PMID: 36348109 DOI: 10.1007/978-3-031-06573-6_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Centromeres are key architectural components of chromosomes. Here, we examine their construction, maintenance, and functionality. Focusing on the mammalian centromere- specific histone H3 variant, CENP-A, we highlight its coevolution with both centromeric DNA and its chaperone, HJURP. We then consider CENP-A de novo deposition and the importance of centromeric DNA recently uncovered with the added value from new ultra-long-read sequencing. We next review how to ensure the maintenance of CENP-A at the centromere throughout the cell cycle. Finally, we discuss the impact of disrupting CENP-A regulation on cancer and cell fate.
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Affiliation(s)
- Daniel Jeffery
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France
| | - Marina Lochhead
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France
| | - Geneviève Almouzni
- Equipe Labellisée Ligue contre le Cancer, Institut Curie, PSL Research University, CNRS, Sorbonne Université, Nuclear Dynamics Unit, UMR3664, Paris, France.
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9
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Kundu S, Ray MD, Sharma A. Interplay between genome organization and epigenomic alterations of pericentromeric DNA in cancer. J Genet Genomics 2021; 48:184-197. [PMID: 33840602 DOI: 10.1016/j.jgg.2021.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 02/07/2021] [Accepted: 02/20/2021] [Indexed: 12/16/2022]
Abstract
In eukaryotic genome biology, the genomic organization inside the three-dimensional (3D) nucleus is highly complex, and whether this organization governs gene expression is poorly understood. Nuclear lamina (NL) is a filamentous meshwork of proteins present at the lining of inner nuclear membrane that serves as an anchoring platform for genome organization. Large chromatin domains termed as lamina-associated domains (LADs), play a major role in silencing genes at the nuclear periphery. The interaction of the NL and genome is dynamic and stochastic. Furthermore, many genes change their positions during developmental processes or under disease conditions such as cancer, to activate certain sorts of genes and/or silence others. Pericentromeric heterochromatin (PCH) is mostly in the silenced region within the genome, which localizes at the nuclear periphery. Studies show that several genes located at the PCH are aberrantly expressed in cancer. The interesting question is that despite being localized in the pericentromeric region, how these genes still manage to overcome pericentromeric repression. Although epigenetic mechanisms control the expression of the pericentromeric region, recent studies about genome organization and genome-nuclear lamina interaction have shed light on a new aspect of pericentromeric gene regulation through a complex and coordinated interplay between epigenomic remodeling and genomic organization in cancer.
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Affiliation(s)
- Subhadip Kundu
- Laboratory of Chromatin and Cancer Epigenetics, Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - M D Ray
- Department of Surgical Oncology, IRCH, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India
| | - Ashok Sharma
- Laboratory of Chromatin and Cancer Epigenetics, Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India.
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10
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Krigerts J, Salmina K, Freivalds T, Zayakin P, Rumnieks F, Inashkina I, Giuliani A, Hausmann M, Erenpreisa J. Differentiating cancer cells reveal early large-scale genome regulation by pericentric domains. Biophys J 2021; 120:711-724. [PMID: 33453273 PMCID: PMC7896032 DOI: 10.1016/j.bpj.2021.01.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/30/2020] [Accepted: 01/07/2021] [Indexed: 02/07/2023] Open
Abstract
Finding out how cells prepare for fate change during differentiation commitment was our task. To address whether the constitutive pericentromere-associated domains (PADs) may be involved, we used a model system with known transcriptome data, MCF-7 breast cancer cells treated with the ErbB3 ligand heregulin (HRG), which induces differentiation and is used in the therapy of cancer. PAD-repressive heterochromatin (H3K9me3), centromere-associated-protein-specific, and active euchromatin (H3K4me3) antibodies, real-time PCR, acridine orange DNA structural test (AOT), and microscopic image analysis were applied. We found a two-step DNA unfolding after 15–20 and 60 min of HRG treatment, respectively. This behavior was consistent with biphasic activation of the early response genes (c-fos - fosL1/myc) and the timing of two transcriptome avalanches reported in the literature. In control, the average number of PADs negatively correlated with their size by scale-free distribution, and centromere clustering in turn correlated with PAD size, both indicating that PADs may create and modulate a suprachromosomal network by fusing and splitting a constant proportion of the constitutive heterochromatin. By 15 min of HRG treatment, the bursting unraveling of PADs from the nucleolus boundary occurred, coinciding with the first step of H3K4me3 chromatin unfolding, confirmed by AOT. The second step after 60 min of HRG treatment was associated with transcription of long noncoding RNA from PADs and peaking of fosL1/c-myc response. We hypothesize that the bursting of PAD clusters under a critical silencing threshold pushes the first transcription avalanche, whereas the destruction of the PAD network enables genome rewiring needed for differentiation repatterning, mediated by early response bivalent genes.
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Affiliation(s)
- Jekabs Krigerts
- Latvian Biomedicine Research and Study Centre, Riga, Latvia; University of Latvia, Riga, Latvia
| | | | - Talivaldis Freivalds
- Institute of Cardiology and Regenerative Medicine, University of Latvia, Riga, Latvia
| | - Pawel Zayakin
- Latvian Biomedicine Research and Study Centre, Riga, Latvia
| | - Felikss Rumnieks
- Latvian Biomedicine Research and Study Centre, Riga, Latvia; University of Latvia, Riga, Latvia
| | - Inna Inashkina
- Latvian Biomedicine Research and Study Centre, Riga, Latvia
| | - Alessandro Giuliani
- Environment and Health Department, Italian National Institute of Health, Rome, Italy
| | - Michael Hausmann
- Kirchhoff Institute for Physics, Heidelberg University, Heidelberg, Germany.
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11
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Spatial modeling of biological patterns shows multiscale organization of Arabidopsis thaliana heterochromatin. Sci Rep 2021; 11:323. [PMID: 33431919 PMCID: PMC7801681 DOI: 10.1038/s41598-020-79158-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 12/01/2020] [Indexed: 01/29/2023] Open
Abstract
The spatial organization in the cell nucleus is tightly linked to genome functions such as gene regulation. Similarly, specific spatial arrangements of biological components such as macromolecular complexes, organelles and cells are involved in many biological functions. Spatial interactions among elementary components of biological systems define their relative positioning and are key determinants of spatial patterns. However, biological variability and the lack of appropriate spatial statistical methods and models limit our current ability to analyze these interactions. Here, we developed a framework to dissect spatial interactions and organization principles by combining unbiased statistical tests, multiple spatial descriptors and new spatial models. We used plant constitutive heterochromatin as a model system to demonstrate the potential of our framework. Our results challenge the common view of a peripheral organization of chromocenters, showing that chromocenters are arranged along both radial and lateral directions in the nuclear space and obey a multiscale organization with scale-dependent antagonistic effects. The proposed generic framework will be useful to identify determinants of spatial organizations and to question their interplay with biological functions.
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12
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Bizhanova A, Kaufman PD. Close to the edge: Heterochromatin at the nucleolar and nuclear peripheries. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2021; 1864:194666. [PMID: 33307247 PMCID: PMC7855492 DOI: 10.1016/j.bbagrm.2020.194666] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 11/11/2020] [Accepted: 11/29/2020] [Indexed: 02/06/2023]
Abstract
Chromatin is a dynamic structure composed of DNA, RNA, and proteins, regulating storage and expression of the genetic material in the nucleus. Heterochromatin plays a crucial role in driving the three-dimensional arrangement of the interphase genome, and in preserving genome stability by maintaining a subset of the genome in a silent state. Spatial genome organization contributes to normal patterns of gene function and expression, and is therefore of broad interest. Mammalian heterochromatin, the focus of this review, mainly localizes at the nuclear periphery, forming Lamina-associated domains (LADs), and at the nucleolar periphery, forming Nucleolus-associated domains (NADs). Together, these regions comprise approximately one-half of mammalian genomes, and most but not all loci within these domains are stochastically placed at either of these two locations after exit from mitosis at each cell cycle. Excitement about the role of these heterochromatic domains in early development has recently been heightened by the discovery that LADs appear at some loci in the preimplantation mouse embryo prior to other chromosomal features like compartmental identity and topologically-associated domains (TADs). While LADs have been extensively studied and mapped during cellular differentiation and early embryonic development, NADs have been less thoroughly studied. Here, we summarize pioneering studies of NADs and LADs, more recent advances in our understanding of cis/trans-acting factors that mediate these localizations, and discuss the functional significance of these associations.
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Affiliation(s)
- Aizhan Bizhanova
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Paul D Kaufman
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Medical School, Worcester, MA 01605, USA.
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13
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Balzano E, Pelliccia F, Giunta S. Genome (in)stability at tandem repeats. Semin Cell Dev Biol 2020; 113:97-112. [PMID: 33109442 DOI: 10.1016/j.semcdb.2020.10.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 09/26/2020] [Accepted: 10/10/2020] [Indexed: 12/12/2022]
Abstract
Repeat sequences account for over half of the human genome and represent a significant source of variation that underlies physiological and pathological states. Yet, their study has been hindered due to limitations in short-reads sequencing technology and difficulties in assembly. A important category of repetitive DNA in the human genome is comprised of tandem repeats (TRs), where repetitive units are arranged in a head-to-tail pattern. Compared to other regions of the genome, TRs carry between 10 and 10,000 fold higher mutation rate. There are several mutagenic mechanisms that can give rise to this propensity toward instability, but their precise contribution remains speculative. Given the high degree of homology between these sequences and their arrangement in tandem, once damaged, TRs have an intrinsic propensity to undergo aberrant recombination with non-allelic exchange and generate harmful rearrangements that may undermine the stability of the entire genome. The dynamic mutagenesis at TRs has been found to underlie individual polymorphism associated with neurodegenerative and neuromuscular disorders, as well as complex genetic diseases like cancer and diabetes. Here, we review our current understanding of the surveillance and repair mechanisms operating within these regions, and we describe how alterations in these protective processes can readily trigger mutational signatures found at TRs, ultimately resulting in the pathological correlation between TRs instability and human diseases. Finally, we provide a viewpoint to counter the detrimental effects that TRs pose in light of their selection and conservation, as important drivers of human evolution.
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Affiliation(s)
- Elisa Balzano
- Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, 00185 Roma, Italy
| | - Franca Pelliccia
- Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, 00185 Roma, Italy
| | - Simona Giunta
- The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA; Dipartimento di Biologia e Biotecnologie "Charles Darwin", Sapienza Università di Roma, 00185 Roma, Italy.
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14
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Qi Y, Reyes A, Johnstone SE, Aryee MJ, Bernstein BE, Zhang B. Data-Driven Polymer Model for Mechanistic Exploration of Diploid Genome Organization. Biophys J 2020; 119:1905-1916. [PMID: 33086041 DOI: 10.1016/j.bpj.2020.09.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/24/2020] [Accepted: 09/08/2020] [Indexed: 12/21/2022] Open
Abstract
Chromosomes are positioned nonrandomly inside the nucleus to coordinate with their transcriptional activity. The molecular mechanisms that dictate the global genome organization and the nuclear localization of individual chromosomes are not fully understood. We introduce a polymer model to study the organization of the diploid human genome. It is data-driven because all parameters can be derived from Hi-C data; it is also a mechanistic model because the energy function is explicitly written out based on a few biologically motivated hypotheses. These two features distinguish the model from existing approaches and make it useful both for reconstructing genome structures and for exploring the principles of genome organization. We carried out extensive validations to show that simulated genome structures reproduce a wide variety of experimental measurements, including chromosome radial positions and spatial distances between homologous pairs. Detailed mechanistic investigations support the importance of both specific interchromosomal interactions and centromere clustering for chromosome positioning. We anticipate the polymer model, when combined with Hi-C experiments, to be a powerful tool for investigating large-scale rearrangements in genome structure upon cell differentiation and tumor progression.
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Affiliation(s)
- Yifeng Qi
- Departments of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Alejandro Reyes
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts; Department of Data Sciences, Dana Farber Cancer Institute, Boston, Massachusetts; Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts
| | - Sarah E Johnstone
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts; Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Center for Cancer Research, Massachusetts General Hospital, Boston, Massachusetts
| | - Martin J Aryee
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts; Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Center for Cancer Research, Massachusetts General Hospital, Boston, Massachusetts
| | - Bradley E Bernstein
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts; Department of Pathology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts; Center for Cancer Research, Massachusetts General Hospital, Boston, Massachusetts
| | - Bin Zhang
- Departments of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts.
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15
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Zeeshan M, Pandey R, Ferguson DJP, Tromer EC, Markus R, Abel S, Brady D, Daniel E, Limenitakis R, Bottrill AR, Le Roch KG, Holder AA, Waller RF, Guttery DS, Tewari R. Real-time dynamics of Plasmodium NDC80 reveals unusual modes of chromosome segregation during parasite proliferation. J Cell Sci 2020; 134:jcs245753. [PMID: 32501284 PMCID: PMC7340582 DOI: 10.1242/jcs.245753] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 04/29/2020] [Indexed: 12/24/2022] Open
Abstract
Eukaryotic cell proliferation requires chromosome replication and precise segregation to ensure daughter cells have identical genomic copies. Species of the genus Plasmodium, the causative agents of malaria, display remarkable aspects of nuclear division throughout their life cycle to meet some peculiar and unique challenges to DNA replication and chromosome segregation. The parasite undergoes atypical endomitosis and endoreduplication with an intact nuclear membrane and intranuclear mitotic spindle. To understand these diverse modes of Plasmodium cell division, we have studied the behaviour and composition of the outer kinetochore NDC80 complex, a key part of the mitotic apparatus that attaches the centromere of chromosomes to microtubules of the mitotic spindle. Using NDC80-GFP live-cell imaging in Plasmodium berghei, we observe dynamic spatiotemporal changes during proliferation, including highly unusual kinetochore arrangements during sexual stages. We identify a very divergent candidate for the SPC24 subunit of the NDC80 complex, previously thought to be missing in Plasmodium, which completes a canonical, albeit unusual, NDC80 complex structure. Altogether, our studies reveal the kinetochore to be an ideal tool to investigate the non-canonical modes of chromosome segregation and cell division in Plasmodium.
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Affiliation(s)
- Mohammad Zeeshan
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Rajan Pandey
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - David J P Ferguson
- Nuffield Department of Clinical Laboratory Science, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Gipsy Lane, Oxford OX3 0BP, UK
| | - Eelco C Tromer
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Robert Markus
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Steven Abel
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Declan Brady
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | - Emilie Daniel
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
| | | | - Andrew R Bottrill
- School of Life Sciences, Gibbelt Hill Campus, University of Warwick, Coventry CV4 7AL, UK
| | - Karine G Le Roch
- Department of Molecular, Cell and Systems Biology, University of California Riverside, Riverside, CA 92521, USA
| | - Anthony A Holder
- Malaria Parasitology Laboratory, The Francis Crick Institute, London NW1 1AT, UK
| | - Ross F Waller
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - David S Guttery
- Leicester Cancer Research Centre, University of Leicester, Leicester LE2 7LX, UK
| | - Rita Tewari
- School of Life Sciences, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2UH, UK
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16
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The Impact of Centromeres on Spatial Genome Architecture. Trends Genet 2019; 35:565-578. [PMID: 31200946 DOI: 10.1016/j.tig.2019.05.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/06/2019] [Accepted: 05/09/2019] [Indexed: 01/01/2023]
Abstract
The development of new technologies and experimental techniques is enabling researchers to see what was once unable to be seen. For example, the centromere was first seen as the mediator between spindle fiber and chromosome during mitosis and meiosis. Although this continues to be its most prominent role, we now know that the centromere functions beyond cellular division with important roles in genome organization and chromatin regulation. Here we aim to share the structures and functions of centromeres in various organisms beginning with the diversity of their DNA sequence anatomies. We zoom out to describe their position in the nucleus and ultimately detail the different ways they contribute to genome organization and regulation at the spatial level.
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17
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Mittal P, Chavan A, Trakroo D, Shah S, Ghosh SK. Outer kinetochore protein Dam1 promotes centromere clustering in parallel with Slk19 in budding yeast. Chromosoma 2019; 128:133-148. [PMID: 30903360 DOI: 10.1007/s00412-019-00694-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 01/14/2019] [Accepted: 02/11/2019] [Indexed: 12/16/2022]
Abstract
A higher order organization of the centromeres in the form of clustering of these DNA loci has been observed in many organisms. While centromere clustering is biologically significant to achieve faithful chromosome segregation, the underlying molecular mechanism is yet to be fully understood. In budding yeast, a kinetochore-associated protein Slk19 is shown to have a role in clustering in association with the microtubules whereas removal of either Slk19 or microtubules alone does not have any effect on the centromere clustering. Furthermore, Slk19 is non-essential for growth and becomes cleaved during anaphase whereas clustering being an essential event occurs throughout the cell cycle. Hence, we searched for an additional factor involved in the clustering and since the integrity of the kinetochore complex is shown to be crucial for centromere clustering, we restricted our search within the complex. We observed that the outermost kinetochore protein Dam1 promotes centromere clustering through stabilization of the kinetochore integrity. While in the absence of Dam1 we failed to detect Slk19 at the centromere, on the other hand, we found almost no Dam1 at the centromere in the absence of Slk19 and microtubules suggesting interdependency between these two pathways. Strikingly, we observed that overexpression of Dam1 or Slk19 could restore the centromere clustering largely in the cells devoid of Slk19 and microtubules or Dam1, respectively. Thus, we propose that in budding yeast, centromere clustering is achieved at least by two parallel pathways, through Dam1 and another via Slk19, in concert with the microtubules suggesting that having a dual mechanism may be crucial for ensuring microtubule capture by the point centromeres where each attaches to only one microtubule.
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Affiliation(s)
- Priyanka Mittal
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Ankita Chavan
- Molecular and Cell Biology Department, University of Connecticut, Storrs, CT, 06269, USA
| | - Deepika Trakroo
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Sanket Shah
- Advanced Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai, 410210, India
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India.
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18
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Ito K, Takizawa T. Nuclear Architecture in the Nervous System: Development, Function, and Neurodevelopmental Diseases. Front Genet 2018; 9:308. [PMID: 30127803 PMCID: PMC6087739 DOI: 10.3389/fgene.2018.00308] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 07/19/2018] [Indexed: 12/22/2022] Open
Abstract
Decades of study have shown that epigenetic regulation plays an important role in neural development and function. Several layers of epigenetic mechanisms control functions of the eukaryotic cell nucleus, a well-organized subcellular organelle with distinct compartments: chromatin, its related architectural proteins, and nuclear bodies. As these components function together in the epigenetic regulation of cellular development and functions, they are collectively termed nuclear architecture. In the nervous system, dynamic rearrangement of nuclear architecture correlates with alteration of transcription programs. During maturation and upon depolarization, neurons undergo a reorganization of nuclear architecture that alters gene expression programs. As such changes allow for specialized functions, including learning and memory, nuclear architecture is distinct among cell types. Studying nuclear architecture of neurons may uncover cell-division-independent mechanisms of global and local changes to nuclear architecture. We herein review recent research concerning nuclear architecture in the nervous system and will discuss its importance to the development, maturation, function, and diseases of the nervous system.
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Affiliation(s)
- Kenji Ito
- Department of Pediatrics, Graduate School of Medicine, Gunma University, Maebashi, Japan.,Division of Stem Cell Pathology, Center for Experimental Medicine and Systems Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Takumi Takizawa
- Department of Pediatrics, Graduate School of Medicine, Gunma University, Maebashi, Japan
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19
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Lukášová E, Kovařík A, Kozubek S. Consequences of Lamin B1 and Lamin B Receptor Downregulation in Senescence. Cells 2018; 7:cells7020011. [PMID: 29415520 PMCID: PMC5850099 DOI: 10.3390/cells7020011] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/24/2018] [Accepted: 01/31/2018] [Indexed: 01/28/2023] Open
Abstract
Anchoring of heterochromatin to the nuclear envelope appears to be an important process ensuring the spatial organization of the chromatin structure and genome function in eukaryotic nuclei. Proteins of the inner nuclear membrane (INM) mediating these interactions are able to recognize lamina-associated heterochromatin domains (termed LAD) and simultaneously bind either lamin A/C or lamin B1. One of these proteins is the lamin B receptor (LBR) that binds lamin B1 and tethers heterochromatin to the INM in embryonic and undifferentiated cells. It is replaced by lamin A/C with specific lamin A/C binding proteins at the beginning of cell differentiation and in differentiated cells. Our functional experiments in cancer cell lines show that heterochromatin in cancer cells is tethered to the INM by LBR, which is downregulated together with lamin B1 at the onset of cell transition to senescence. The downregulation of these proteins in senescent cells leads to the detachment of centromeric repetitive sequences from INM, their relocation to the nucleoplasm, and distension. In cells, the expression of LBR and LB1 is highly coordinated as evidenced by the reduction of both proteins in LBR shRNA lines. The loss of the constitutive heterochromatin structure containing LADs results in changes in chromatin architecture and genome function and can be the reason for the permanent loss of cell proliferation in senescence.
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Affiliation(s)
- Emilie Lukášová
- Department of Cell Biology and Radiobiology, Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, Brno 61265, Czech Republic.
- Department of Molecular Epigenetics, Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, Brno 61265, Czech Republic.
| | - Aleš Kovařík
- Department of Molecular Epigenetics, Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, Brno 61265, Czech Republic.
| | - Stanislav Kozubek
- Department of Cell Biology and Radiobiology, Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, Brno 61265, Czech Republic.
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20
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Fujita Y, Yamashita T. Spatial organization of genome architecture in neuronal development and disease. Neurochem Int 2017; 119:49-56. [PMID: 28757389 DOI: 10.1016/j.neuint.2017.06.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 06/19/2017] [Accepted: 06/26/2017] [Indexed: 01/19/2023]
Abstract
Although mammalian genomes encode genetic information in their linear sequences, their fundamental function with regard to gene expression depends on the higher-order structure of chromosomes. Current techniques for the evaluation of chromosomal structure have revealed that genomes are arranged at several hierarchical levels in three-dimensional space. The spatial organization of genomes involves the formation of chromatin loops that bypass a wide range of genomic distances, providing a connection between enhancers and chromosomal domains. Furthermore, they form chromatin domains that are arranged into chromosome territories in the three-dimensional space of the cell nucleus. Recent studies have shown that the spatial organization of the genome is essential for normal brain development and function. Activity-dependent alterations in the spatial organization of the genome can regulate transcriptional activity related to neuronal plasticity. Disruptions in the higher-order chromatin architecture have been implicated in neuropsychiatric disorders, such as cognitive dysfunction and anxiety. Here, we discuss the growing interest in the role of genome organization in brain development and neurological disorders.
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Affiliation(s)
- Yuki Fujita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI Immunology Frontier Research Center, Osaka University, Suita, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Graduate School of Frontier Biosciences, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
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21
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Karamysheva TV, Torgasheva AA, Yefremov YR, Bogomolov AG, Liehr T, Borodin PM, Rubtsov NB. Spatial organization of fibroblast and spermatocyte nuclei with different B-chromosome content in Korean field mouse, Apodemus peninsulae (Rodentia, Muridae). Genome 2017; 60:815-824. [PMID: 28732174 DOI: 10.1139/gen-2017-0029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Korean field mouse (Apodemus peninsulae) shows a wide variation in the number of B chromosomes composed of constitutive heterochromatin. For this reason, it provides a good model to study the influence of the number of centromeres and amount of heterochromatin on spatial organization of interphase nuclei. We analyzed the three-dimensional organization of fibroblast and spermatocyte nuclei of the field mice carrying a different number of B chromosomes using laser scanning microscopy and 3D fluorescence in situ hybridization. We detected a co-localization of the B chromosomes with constitutive heterochromatin of the chromosomes of the basic set. We showed a non-random distribution of B chromosomes in the spermatocyte nuclei. Unpaired B chromosomes showed a tendency to occur in the compartment formed by the unpaired part of the XY bivalent.
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Affiliation(s)
- Tatyana V Karamysheva
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Anna A Torgasheva
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia
| | - Yaroslav R Yefremov
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.,b Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Anton G Bogomolov
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.,b Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Thomas Liehr
- c Jena University Hospital, Friedrich Schiller University, Institute of Human Genetics, Kollegiengasse 10, D-07743 Jena, Germany
| | - Pavel M Borodin
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.,b Novosibirsk State University, 630090 Novosibirsk, Russia
| | - Nikolay B Rubtsov
- a Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, 630090 Novosibirsk, Russia.,b Novosibirsk State University, 630090 Novosibirsk, Russia
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22
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Lamina-Associated Domains: Links with Chromosome Architecture, Heterochromatin, and Gene Repression. Cell 2017; 169:780-791. [PMID: 28525751 DOI: 10.1016/j.cell.2017.04.022] [Citation(s) in RCA: 628] [Impact Index Per Article: 89.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 04/11/2017] [Accepted: 04/14/2017] [Indexed: 01/06/2023]
Abstract
In metazoan cell nuclei, hundreds of large chromatin domains are in close contact with the nuclear lamina. Such lamina-associated domains (LADs) are thought to help organize chromosomes inside the nucleus and have been associated with gene repression. Here, we discuss the properties of LADs, the molecular mechanisms that determine their association with the nuclear lamina, their dynamic links with other nuclear compartments, and their proposed roles in gene regulation.
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23
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van de Werken HJG, Haan JC, Feodorova Y, Bijos D, Weuts A, Theunis K, Holwerda SJB, Meuleman W, Pagie L, Thanisch K, Kumar P, Leonhardt H, Marynen P, van Steensel B, Voet T, de Laat W, Solovei I, Joffe B. Small chromosomal regions position themselves autonomously according to their chromatin class. Genome Res 2017; 27:922-933. [PMID: 28341771 PMCID: PMC5453326 DOI: 10.1101/gr.213751.116] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 03/22/2017] [Indexed: 11/24/2022]
Abstract
The spatial arrangement of chromatin is linked to the regulation of nuclear processes. One striking aspect of nuclear organization is the spatial segregation of heterochromatic and euchromatic domains. The mechanisms of this chromatin segregation are still poorly understood. In this work, we investigated the link between the primary genomic sequence and chromatin domains. We analyzed the spatial intranuclear arrangement of a human artificial chromosome (HAC) in a xenospecific mouse background in comparison to an orthologous region of native mouse chromosome. The two orthologous regions include segments that can be assigned to three major chromatin classes according to their gene abundance and repeat repertoire: (1) gene-rich and SINE-rich euchromatin; (2) gene-poor and LINE/LTR-rich heterochromatin; and (3) gene-depleted and satellite DNA-containing constitutive heterochromatin. We show, using fluorescence in situ hybridization (FISH) and 4C-seq technologies, that chromatin segments ranging from 0.6 to 3 Mb cluster with segments of the same chromatin class. As a consequence, the chromatin segments acquire corresponding positions in the nucleus irrespective of their chromosomal context, thereby strongly suggesting that this is their autonomous property. Interactions with the nuclear lamina, although largely retained in the HAC, reveal less autonomy. Taken together, our results suggest that building of a functional nucleus is largely a self-organizing process based on mutual recognition of chromosome segments belonging to the major chromatin classes.
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Affiliation(s)
- Harmen J G van de Werken
- Cancer Computational Biology Center, Erasmus MC Cancer Institute & Department of Urology, Erasmus MC Cancer Institute, Erasmus University Medical Center, 3015 CN, Rotterdam, The Netherlands.,Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Josien C Haan
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Yana Feodorova
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Dominika Bijos
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - An Weuts
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Koen Theunis
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Sjoerd J B Holwerda
- Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Wouter Meuleman
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Ludo Pagie
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Katharina Thanisch
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Parveen Kumar
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Heinrich Leonhardt
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Peter Marynen
- Human Genome Laboratory, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Bas van Steensel
- Division of Gene Regulation, Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands
| | - Thierry Voet
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, 3000, Belgium
| | - Wouter de Laat
- Hubrecht Institute-KNAW & University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Irina Solovei
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Boris Joffe
- Department of Biology II, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
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24
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Making Sense of the Tangle: Insights into Chromatin Folding and Gene Regulation. Genes (Basel) 2016; 7:genes7100071. [PMID: 27669308 PMCID: PMC5083910 DOI: 10.3390/genes7100071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 08/10/2016] [Accepted: 09/07/2016] [Indexed: 01/03/2023] Open
Abstract
Proximity ligation assays such as circularized chromosome conformation capture and high-throughput chromosome capture assays have shed light on the structural organization of the interphase genome. Functional topologically associating domains (TADs) that constitute the building blocks of genomic organization are disrupted and reconstructed during the cell cycle. Epigenetic memory, as well as the sequence of chromosomes, regulate TAD reconstitution. Sub-TAD domains that are invariant across cell types have been identified, and contacts between these domains, rather than looping, are speculated to drive chromatin folding. Replication domains are established simultaneously with TADs during the cell cycle and the two correlate well in terms of characteristic features, such as lamin association and histone modifications. CCCTC-binding factor (CTCF) and cohesin cooperate across different cell types to regulate genes and genome organization. CTCF elements that demarcate TAD boundaries are commonly disrupted in cancer and promote oncogene activation. Chromatin looping facilitates interactions between distant promoters and enhancers, and the resulting enhanceosome complex promotes gene expression. Deciphering the chromatin tangle requires comprehensive integrative analyses of DNA- and protein-dependent factors that regulate genomic organization.
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25
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Meaburn KJ. Spatial Genome Organization and Its Emerging Role as a Potential Diagnosis Tool. Front Genet 2016; 7:134. [PMID: 27507988 PMCID: PMC4961005 DOI: 10.3389/fgene.2016.00134] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 07/13/2016] [Indexed: 12/12/2022] Open
Abstract
In eukaryotic cells the genome is highly spatially organized. Functional relevance of higher order genome organization is implied by the fact that specific genes, and even whole chromosomes, alter spatial position in concert with functional changes within the nucleus, for example with modifications to chromatin or transcription. The exact molecular pathways that regulate spatial genome organization and the full implication to the cell of such an organization remain to be determined. However, there is a growing realization that the spatial organization of the genome can be used as a marker of disease. While global genome organization patterns remain largely conserved in disease, some genes and chromosomes occupy distinct nuclear positions in diseased cells compared to their normal counterparts, with the patterns of reorganization differing between diseases. Importantly, mapping the spatial positioning patterns of specific genomic loci can distinguish cancerous tissue from benign with high accuracy. Genome positioning is an attractive novel biomarker since additional quantitative biomarkers are urgently required in many cancer types. Current diagnostic techniques are often subjective and generally lack the ability to identify aggressive cancer from indolent, which can lead to over- or under-treatment of patients. Proof-of-principle for the use of genome positioning as a diagnostic tool has been provided based on small scale retrospective studies. Future large-scale studies are required to assess the feasibility of bringing spatial genome organization-based diagnostics to the clinical setting and to determine if the positioning patterns of specific loci can be useful biomarkers for cancer prognosis. Since spatial reorganization of the genome has been identified in multiple human diseases, it is likely that spatial genome positioning patterns as a diagnostic biomarker may be applied to many diseases.
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Affiliation(s)
- Karen J. Meaburn
- Cell Biology of Genomes Group, National Cancer Institute, National Institutes of HealthBethesda, MD, USA
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26
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Population-based 3D genome structure analysis reveals driving forces in spatial genome organization. Proc Natl Acad Sci U S A 2016; 113:E1663-72. [PMID: 26951677 DOI: 10.1073/pnas.1512577113] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Conformation capture technologies (e.g., Hi-C) chart physical interactions between chromatin regions on a genome-wide scale. However, the structural variability of the genome between cells poses a great challenge to interpreting ensemble-averaged Hi-C data, particularly for long-range and interchromosomal interactions. Here, we present a probabilistic approach for deconvoluting Hi-C data into a model population of distinct diploid 3D genome structures, which facilitates the detection of chromatin interactions likely to co-occur in individual cells. Our approach incorporates the stochastic nature of chromosome conformations and allows a detailed analysis of alternative chromatin structure states. For example, we predict and experimentally confirm the presence of large centromere clusters with distinct chromosome compositions varying between individual cells. The stability of these clusters varies greatly with their chromosome identities. We show that these chromosome-specific clusters can play a key role in the overall chromosome positioning in the nucleus and stabilizing specific chromatin interactions. By explicitly considering genome structural variability, our population-based method provides an important tool for revealing novel insights into the key factors shaping the spatial genome organization.
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27
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Solovei I, Thanisch K, Feodorova Y. How to rule the nucleus: divide et impera. Curr Opin Cell Biol 2016; 40:47-59. [PMID: 26938331 DOI: 10.1016/j.ceb.2016.02.014] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 02/04/2016] [Accepted: 02/14/2016] [Indexed: 01/14/2023]
Abstract
Genome-wide molecular studies have provided new insights into the organization of nuclear chromatin by revealing the presence of chromatin domains of differing transcriptional activity, frequency of cis-interactions, proximity to scaffolding structures and replication timing. These studies have not only brought our understanding of genome function to a new level, but also offered functional insight for many phenomena observed in microscopic studies. In this review, we discuss the major principles of nuclear organization based on the spatial segregation of euchromatin and heterochromatin, as well as the dynamic genome rearrangements occurring during cell differentiation and development. We hope to unite the existing molecular and microscopic data on genome organization to get a holistic view of the nucleus, and propose a model, in which repeat repertoire together with scaffolding structures blueprint the functional nuclear architecture.
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Affiliation(s)
- Irina Solovei
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany.
| | - Katharina Thanisch
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany
| | - Yana Feodorova
- Department of Biology II, Ludwig Maximilians University Munich, Grosshadernerstrasse 2, Planegg-Martinsried 82152, Germany; Department of Medical Biology, Medical University-Plovdiv, Boulevard Vasil Aprilov 15A, Plovdiv 4000, Bulgaria
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Chabouté ME, Berr A. GIP Contributions to the Regulation of Centromere at the Interface Between the Nuclear Envelope and the Nucleoplasm. FRONTIERS IN PLANT SCIENCE 2016; 7:118. [PMID: 26904080 PMCID: PMC4744857 DOI: 10.3389/fpls.2016.00118] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/22/2016] [Indexed: 05/16/2023]
Abstract
Centromeres are known as specific chromatin domains without which eukaryotic cells cannot divide properly during mitosis. Despite the considerable efforts to understand the centromere/kinetochore assembly during mitosis, until recently, comparatively few studies have dealt with the regulation of centromere during interphase. Here, we briefly review and discuss past and recent advances about the architecture of centromeres and their regulation during the cell cycle. Furthermore, we highlight and discuss new findings and hypotheses regarding the specific regulation of centromeres in both plant and animal nuclei, especially with GIP proteins at the interface between the nuclear envelope and the nucleoplasm.
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Idziak D, Robaszkiewicz E, Hasterok R. Spatial distribution of centromeres and telomeres at interphase varies among Brachypodium species. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6623-6634. [PMID: 26208647 PMCID: PMC4623680 DOI: 10.1093/jxb/erv369] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this study the 3-D distribution of centromeres and telomeres was analysed in the interphase nuclei of three Brachypodium species, i.e. B. distachyon (2n=10), B. stacei (2n=20) and B. hybridum (2n=30), which is presumably a hybrid between the first two species. Using fluorescence in situ hybridization (FISH) with centromeric and telomeric DNA probes, it was observed that the majority of B. distachyon nuclei in the root tip cells displayed the Rabl configuration while both B. stacei and B. hybridum mostly lacked the centromere-telomere polarization. In addition, differentiated leaf cells of B. distachyon did not display the Rabl pattern. In order to analyse the possible connection between the occurrence of the Rabl pattern and the phase of cell cycle or DNA content, FISH was combined with digital image cytometry. The results revealed that the frequency of nuclei with the Rabl configuration in the root tip nuclei was positively correlated with an increase in DNA content, which resulted from DNA replication. Also, the analysis of the influence of the nuclear shape on the nuclear architecture indicated that an increasing elongation of the nuclei negatively affected the occurrence of the Rabl pattern. Some possible explanations of these phenomena are discussed.
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Affiliation(s)
- Dominika Idziak
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, 28 Jagiellonska Street, 40-032 Katowice, Poland
| | - Ewa Robaszkiewicz
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, 28 Jagiellonska Street, 40-032 Katowice, Poland
| | - Robert Hasterok
- Department of Plant Anatomy and Cytology, Faculty of Biology and Environmental Protection, University of Silesia in Katowice, 28 Jagiellonska Street, 40-032 Katowice, Poland
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30
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Simões M, Martins C, Ferreira F. Early intranuclear replication of African swine fever virus genome modifies the landscape of the host cell nucleus. Virus Res 2015; 210:1-7. [PMID: 26183880 DOI: 10.1016/j.virusres.2015.07.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 07/03/2015] [Accepted: 07/06/2015] [Indexed: 12/31/2022]
Abstract
Although African swine fever virus (ASFV) replicates in viral cytoplasmic factories, the presence of viral DNA within the host cell nucleus has been previously reported to be essential for productive infection. Herein, we described, for the first time, the intranuclear distribution patterns of viral DNA replication events, preceding those that occur in the cytoplasmic compartment. Using BrdU pulse-labelling experiments, newly synthesized ASFV genomes were exclusively detected inside the host cell nucleus at the early phase of infection, both in swine monocyte-derived macrophages (MDMs) and Vero cells. From 8hpi onwards, BrdU labelling was only observed in ASFV cytoplasmic factories. Our results also show that ASFV specifically activates the Ataxia Telangiectasia Mutated Rad-3 related (ATR) pathway in ASFV-infected swine MDMs from the early phase of infection, most probably because ASFV genome is recognized as foreign DNA. Morphological changes of promyelocytic leukaemia nuclear bodies (PML-NBs), nuclear speckles and Cajal bodies were also found in ASFV-infected swine MDMs, strongly suggesting the viral modulation of cellular antiviral responses and cellular transcription, respectively. As described for other viral infections, the nuclear reorganization that takes place during ASFV infection may also provide an environment that favours its intranuclear replication events. Altogether, our results contribute for a better understanding of ASFV replication strategies, starting with an essential intranuclear DNA replication phase which induces host nucleus changes towards a successful viral infection.
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Affiliation(s)
- Margarida Simões
- CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Carlos Martins
- CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Fernando Ferreira
- CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal.
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31
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Ollion J, Loll F, Cochennec J, Boudier T, Escudé C. Proliferation-dependent positioning of individual centromeres in the interphase nucleus of human lymphoblastoid cell lines. Mol Biol Cell 2015; 26:2550-60. [PMID: 25947134 PMCID: PMC4571307 DOI: 10.1091/mbc.e14-05-1002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 04/27/2015] [Indexed: 01/01/2023] Open
Abstract
Centromeres are not randomly distributed in interphase nuclei. High-throughput imaging provides an accurate characterization of how their organization varies as a function of the proliferation state in human lymphoblastoid cells. The results suggest the existence of mechanisms that drive the nuclear positioning of centromeres. The cell nucleus is a highly organized structure and plays an important role in gene regulation. Understanding the mechanisms that sustain this organization is therefore essential for understanding genome function. Centromeric regions (CRs) of chromosomes have been known for years to adopt specific nuclear positioning patterns, but the significance of this observation is not yet completely understood. Here, using a combination of fluorescence in situ hybridization and immunochemistry on fixed human cells and high-throughput imaging, we directly and quantitatively investigated the nuclear positioning of specific human CRs. We observe differential attraction of individual CRs toward both the nuclear border and the nucleoli, the former being enhanced in nonproliferating cells and the latter being enhanced in proliferating cells. Similar positioning patterns are observed in two different lymphoblastoid cell lines. Moreover, the positioning of CRs differs from that of noncentromeric regions, and CRs display specific orientations within chromosome territories. These results suggest the existence of not-yet-characterized mechanisms that drive the nuclear positioning of CRs and therefore pave the way toward a better understanding of how CRs affect nuclear organization.
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Affiliation(s)
- Jean Ollion
- Institut National de la Santé et de la Recherche Médicale U1154, Centre National de la Recherche Scientifique UMR7196, Muséum National d'Histoire Naturelle, 75231 Paris, France
| | - François Loll
- Institut National de la Santé et de la Recherche Médicale U1154, Centre National de la Recherche Scientifique UMR7196, Muséum National d'Histoire Naturelle, 75231 Paris, France
| | - Julien Cochennec
- Institut National de la Santé et de la Recherche Médicale U1154, Centre National de la Recherche Scientifique UMR7196, Muséum National d'Histoire Naturelle, 75231 Paris, France
| | - Thomas Boudier
- Université Pierre et Marie Curie, Sorbonne Universités, 75005 Paris, France
| | - Christophe Escudé
- Institut National de la Santé et de la Recherche Médicale U1154, Centre National de la Recherche Scientifique UMR7196, Muséum National d'Histoire Naturelle, 75231 Paris, France
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32
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Chromatin-Driven Behavior of Topologically Associating Domains. J Mol Biol 2015; 427:608-25. [DOI: 10.1016/j.jmb.2014.09.013] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 09/17/2014] [Accepted: 09/23/2014] [Indexed: 12/19/2022]
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Agarwal M, Mehta G, Ghosh SK. Role of Ctf3 and COMA subcomplexes in meiosis: Implication in maintaining Cse4 at the centromere and numeric spindle poles. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:671-84. [PMID: 25562757 DOI: 10.1016/j.bbamcr.2014.12.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 12/24/2014] [Accepted: 12/29/2014] [Indexed: 12/16/2022]
Abstract
During mitosis and meiosis, kinetochore, a conserved multi-protein complex, connects microtubule with the centromere and promotes segregation of the chromosomes. In budding yeast, central kinetochore complex named Ctf19 has been implicated in various functions and is believed to be made up of three biochemically distinct subcomplexes: COMA, Ctf3 and Iml3-Chl4. In this study, we aimed to identify whether Ctf3 and COMA subcomplexes have any unshared function at the kinetochore. Our data suggests that both these subcomplexes may work as a single functional unit without any unique functions, which we tested. Analysis of severity of the defects in the mutants suggests that COMA is epistatic to Ctf3 subcomplex. Interestingly, we noticed that these subcomplexes affect the organization of mitotic and meiotic kinetochores with subtle differences and they promote maintenance of Cse4 at the centromeres specifically during meiosis which is similar to the role of Mis6 (Ctf3 homolog) in fission yeast during mitosis. Interestingly, analysis of ctf3Δ and ctf19Δ mutants revealed a novel role of Ctf19 complex in regulation of SPB cohesion and duplication in meiosis.
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Affiliation(s)
- Meenakshi Agarwal
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai 40076, India
| | - Gunjan Mehta
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai 40076, India
| | - Santanu K Ghosh
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Bombay, Powai, Mumbai 40076, India.
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34
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Strickfaden H, Zunhammer A, van Koningsbruggen S, Köhler D, Cremer T. 4D Chromatin dynamics in cycling cells. Nucleus 2014. [DOI: 10.4161/nucl.11969] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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35
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Padeken J, Heun P. Nucleolus and nuclear periphery: velcro for heterochromatin. Curr Opin Cell Biol 2014; 28:54-60. [PMID: 24690547 DOI: 10.1016/j.ceb.2014.03.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Revised: 03/06/2014] [Accepted: 03/08/2014] [Indexed: 01/09/2023]
Abstract
Heterochromatin was first defined by Emil Heitz in 1928 by light microscopy. In the 1950s electron microscopy studies revealed that heterochromatin preferentially localizes to the nuclear periphery and around the nucleolus. While the use of genomic approaches led to the genome wide identification of lamina-associated and nucleolus-associated chromatin domains (LADs, NADs), recent studies now shed light on the processes mediating this topology and its dynamics. The identification of different factors on all regulatory levels, such as transcription factors, histone modifications, chromatin proteins, DNA sequences and non-coding RNAs, suggests the involvement of multiple distinct tethering pathways. Positioning at these nuclear sub-compartments is often but not always associated with transcriptional silencing, underlining the importance of the pre-existing chromatin context.
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Affiliation(s)
- Jan Padeken
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse, 66, 4058 Basel, Switzerland
| | - Patrick Heun
- Max Planck Institute of Immunobiology and Epigenetics, Stübeweg 51, 79108 Freiburg, Germany.
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36
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Ragoczy T, Telling A, Scalzo D, Kooperberg C, Groudine M. Functional redundancy in the nuclear compartmentalization of the late-replicating genome. Nucleus 2014; 5:626-35. [PMID: 25493640 PMCID: PMC4615584 DOI: 10.4161/19491034.2014.990863] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 10/15/2014] [Accepted: 10/24/2014] [Indexed: 12/14/2022] Open
Abstract
The eukaryotic nucleus is structurally and functionally organized, as reflected in the distribution of its protein and DNA components. The genome itself is segregated into euchromatin and heterochromatin that replicate in a distinct spatio-temporal manner. We used a combination of fluorescence in situ hybridization (FISH) and DamID to investigate the localization of the early and late replicating components of the genome in a lymphoblastoid cell background. Our analyses revealed that the bulk of late replicating chromatin localizes to the nuclear peripheral heterochromatin (PH) in a chromosome size and gene density dependent manner. Late replicating DNA on small chromosomes exhibits a much lower tendency to localize to PH and tends to associate with alternate repressive subcompartments such as pericentromeric (PCH) and perinucleolar heterochromatin (PNH). Furthermore, multicolor FISH analysis revealed that late replicating loci, particularly on the smaller chromosomes, may associate with any of these 3 repressive subcompartments, including more than one at the same time. These results suggest a functional equivalence or redundancy among the 3 subcompartments. Consistent with this notion, disruption of nucleoli resulted in an increased association of late replicating loci with peripheral heterochromatin. Our analysis reveals that rather than considering the morphologically distinct PH, PCH and PNH as individual subcompartments, they should be considered in aggregate as a functional compartment for late replicating chromatin.
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Key Words
- Chr, chromosome
- DamID
- DamID, Dam identification
- EU, 5-Ethynyl uridine
- FISH, fluorescence in situ hybridization
- LAD, lamina associated domain
- NOR, nucleolar organizing region
- PCH, pericentromeric heterochromatin
- PH, peripheral heterochromatin
- PNH, perinucleolar heterochromatin
- heterochromatin
- localization
- nuclear organization
- nuclear periphery, pericentromeric heterochromatin
- perinucleolar heterochromatin
- replication timing
- repressive compartments
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Affiliation(s)
- Tobias Ragoczy
- Division of Basic Sciences; Fred Hutchinson Cancer Research Center; Seattle, WA USA
| | - Agnes Telling
- Division of Basic Sciences; Fred Hutchinson Cancer Research Center; Seattle, WA USA
| | - David Scalzo
- Division of Basic Sciences; Fred Hutchinson Cancer Research Center; Seattle, WA USA
| | - Charles Kooperberg
- Division of Public Health Sciences; Fred Hutchinson Cancer Research Center; Seattle, WA USA
| | - Mark Groudine
- Division of Basic Sciences; Fred Hutchinson Cancer Research Center; Seattle, WA USA
- Department of Radiation Oncology; University of Washington School of Medicine; Seattle, WA USA
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37
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Studying the cerebellar DNA damage response in the tissue culture dish. Mech Ageing Dev 2013; 134:496-505. [DOI: 10.1016/j.mad.2013.04.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/29/2013] [Accepted: 04/01/2013] [Indexed: 11/30/2022]
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38
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Farrell M, Gubbels MJ. The Toxoplasma gondii kinetochore is required for centrosome association with the centrocone (spindle pole). Cell Microbiol 2013; 16:78-94. [PMID: 24015880 DOI: 10.1111/cmi.12185] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 08/01/2013] [Accepted: 08/14/2013] [Indexed: 12/17/2022]
Abstract
The kinetochore is a multi-protein structure assembled on eukaryotic centromeres mediating chromosome attachment to spindle microtubules. Here we identified the kinetochore proteins Nuf2 and Ndc80 in the apicomplexan parasite Toxoplasma gondii. Localization revealed that kinetochores remain clustered throughout the cell cycle and colocalize with clustered centromeres at the centrocone, a structure containing the spindle pole embedded in the nuclear envelope. Pharmacological disruption of microtubules resulted in partial loss of some kinetochore and centromere clustering, indicating microtubules are necessary but not strictly required for kinetochore clustering. Generation of a TgNuf2 conditional knock-down strain revealed it is essential for chromosome segregation, but dispensable for centromere clustering. The centromeres actually remained associated with the centrocone suggesting microtubule binding is not required for their interaction with the spindle pole. The most striking observation upon TgNuf2 depletion was that the centrosome behaved normally, but that it lost its association with the centrocone. This suggests that microtubules are essential to maintain contact between the centrosome and chromosomes, and this interaction is critical for the partitioning of the nuclei into the two daughter parasites. Finally, genetic complementation experiments with mutated TgNuf2 constructs highlighted an apicomplexan-specific motif with a putative role in nuclear localization.
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Affiliation(s)
- Megan Farrell
- Department of Biology, Boston College, 140 Commonwealth Avenue, Higgins Hall 355, Chestnut Hill, MA, 02467, USA
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39
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Ritland Politz JC, Scalzo D, Groudine M. Something silent this way forms: the functional organization of the repressive nuclear compartment. Annu Rev Cell Dev Biol 2013; 29:241-70. [PMID: 23834025 PMCID: PMC3999972 DOI: 10.1146/annurev-cellbio-101512-122317] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The repressive compartment of the nucleus is comprised primarily of telomeric and centromeric regions, the silent portion of ribosomal RNA genes, the majority of transposable element repeats, and facultatively repressed genes specific to different cell types. This compartment localizes into three main regions: the peripheral heterochromatin, perinucleolar heterochromatin, and pericentromeric heterochromatin. Both chromatin remodeling proteins and transcription of noncoding RNAs are involved in maintenance of repression in these compartments. Global reorganization of the repressive compartment occurs at each cell division, during early development, and during terminal differentiation. Differential action of chromatin remodeling complexes and boundary element looping activities are involved in mediating these organizational changes. We discuss the evidence that heterochromatin formation and compartmentalization may drive nuclear organization.
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Affiliation(s)
| | - David Scalzo
- Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
| | - Mark Groudine
- Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
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40
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Wei Z, Huang D, Gao F, Chang WH, An W, Coetzee GA, Wang K, Lu W. Biological implications and regulatory mechanisms of long-range chromosomal interactions. J Biol Chem 2013; 288:22369-77. [PMID: 23779110 DOI: 10.1074/jbc.r113.485292] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Development of high-throughput sequencing-based methods has enabled us to examine nuclear architecture at unprecedented resolution, allowing further examination of the function of long-range chromosomal interactions. Here, we review methods used to investigate novel long-range chromosomal interactions and genome-wide organization of chromatin. We further discuss transcriptional activation and silencing in relation to organization and positioning of gene loci and regulation of chromatin organization through protein complexes and noncoding RNAs.
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Affiliation(s)
- Zong Wei
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA
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41
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Alladin N, Moskovtsev SI, Russell H, Kenigsberg S, Lulat AGM, Librach CL. The three-dimensional image analysis of the chromocenter in motile and immotile human sperm. Syst Biol Reprod Med 2013; 59:146-52. [PMID: 23445178 DOI: 10.3109/19396368.2013.772679] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chromosomes in human spermatozoa are arranged non-randomly with the centromeres of non-homologous chromosomes forming a chromocenter. We have compared motile and immotile sperm populations in normozoospermic patients to determine if there is any dissimilarity in the formation of the chromocenter and the nuclear position of chromosome 17. Based on the differences between motile and immotile populations, we propose for the 'optimal' nuclear organization to be defined as containing 1 to 3 chromocenter(s) with central radial and median longitudinal position for the centromere of chromosome 17. By this definition, 42% of motile spermatozoa had 'optima' nuclei, in comparison to 25% of immotile spermatozoa (P < 0.05). Immotile spermatozoa exhibited a greater disruption in the formation of the chromocenter, altered position of the centromere of chromosome 17, and were more prone to chemical decondensation, resulting in higher nuclear and chromocenter volumes. The altered topology of the chromosomes might lead to the disruption of the sequence of events involved in fertilization and early embryonic development.
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42
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Richmond D, Rizkallah R, Liang F, Hurt MM, Wang Y. Slk19 clusters kinetochores and facilitates chromosome bipolar attachment. Mol Biol Cell 2013; 24:566-77. [PMID: 23283988 PMCID: PMC3583661 DOI: 10.1091/mbc.e12-07-0552] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Yeast kinetochore protein Slk19 is required for kinetochore clustering, and nocodazole exposure to slk19 mutant cells causes impaired kinetochore capture and delayed chromosome bipolar attachment after nocodazole washout. In all eukaryotic cells, DNA is packaged into multiple chromosomes that are linked to microtubules through a large protein complex called a kinetochore. Previous data show that the kinetochores are clustered together during most of the cell cycle, but the mechanism and the biological significance of kinetochore clustering are unknown. As a kinetochore protein in budding yeast, the role of Slk19 in the stability of the anaphase spindle has been well studied, but its function in chromosome segregation has remained elusive. Here we show that Slk19 is required for kinetochore clustering when yeast cells are treated with the microtubule-depolymerizing agent nocodazole. We further find that slk19Δ mutant cells exhibit delayed kinetochore capture and chromosome bipolar attachment after the disruption of the kinetochore–microtubule interaction by nocodazole, which is likely attributed to defective kinetochore clustering. In addition, we show that Slk19 interacts with itself, suggesting that the dimerization of Slk19 may mediate the interaction between kinetochores for clustering. Therefore Slk19 likely acts as kinetochore glue that clusters kinetochores to facilitate efficient and faithful chromosome segregation.
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Affiliation(s)
- Daniel Richmond
- Department of Biomedical Sciences, College of Medicine, Florida State University, Tallahassee, FL 32306, USA
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43
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Fransz P, de Jong H. From nucleosome to chromosome: a dynamic organization of genetic information. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 66:4-17. [PMID: 21443619 DOI: 10.1111/j.1365-313x.2011.04526.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Gene activity is controlled at different levels of chromatin organization, which involve genomic sequences, nucleosome structure, chromatin folding and chromosome arrangement. These levels are interconnected and influence each other. At the basic level nucleosomes generally occlude the DNA sequence from interacting with DNA-binding proteins. Evidently, nucleosome positioning is a major factor in gene control and chromatin organization. Understanding the biological rules that govern the deposition and removal of the nucleosomes to and from the chromatin fiber is the key to understanding gene regulation and chromatin organization. In this review we describe and discuss the relationship between the different levels of chromatin organization in plants and animals.
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Affiliation(s)
- Paul Fransz
- Nuclear Organization Group, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands.
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44
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Berchtold D, Fesser S, Bachmann G, Kaiser A, Eilert JC, Frohns F, Sadoni N, Muck J, Kremmer E, Eick D, Layer PG, Zink D. Nuclei of chicken neurons in tissues and three-dimensional cell cultures are organized into distinct radial zones. Chromosome Res 2011; 19:165-82. [PMID: 21249442 DOI: 10.1007/s10577-010-9182-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 12/22/2010] [Accepted: 12/22/2010] [Indexed: 12/15/2022]
Abstract
We used chicken retinospheroids (RS) to study the nuclear architecture of vertebrate cells in a three-dimensional (3D) cell culture system. The results showed that the different neuronal cell types of RS displayed an extreme form of radial nuclear organization. Chromatin was arranged into distinct radial zones which became already visible after DAPI staining. The distinct zones were enriched in different chromatin modifications and in different types of chromosomes. Active isoforms of RNA polymerase II were depleted in the outermost zone. Also chromocenters and nucleoli were radially aligned in the nuclear interior. The splicing factor SC35 was enriched at the central zone and did not show the typical speckled pattern of distribution. Evaluation of neuronal and non-neuronal chicken tissues showed that the highly ordered form of radial nuclear organization was also present in neuronal chicken tissues. Furthermore, the data revealed that the neuron-specific nuclear organization was remodeled when cells spread on a flat substrate. Monolayer cultures of a chicken cell line did not show this extreme form of radial organization. Rather, such monolayer cultures displayed features of nuclear organization which have been described before for many different types of monolayer cells. The finding that an extreme form radial nuclear organization, which has not been described before, is present in RS and tissues, but not in cells spread on a flat substrate, suggests that it would be important to complement studies on nuclear architecture performed with monolayer cells by studies on 3D cell culture systems and tissues.
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Affiliation(s)
- Doris Berchtold
- Department Biologie II, Ludwig-Maximilians-Universität (LMU) München, Biozentrum, Grosshadernerstr. 2, 82152, Planegg-Martinsried, Germany
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Cremer T, Zakhartchenko V. Nuclear architecture in developmental biology and cell specialisation. Reprod Fertil Dev 2011; 23:94-106. [DOI: 10.1071/rd10249] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Epigenetic changes, including DNA methylation patterns, histone modifications and histone variants, as well as chromatin remodelling play a fundamental role in the regulation of pre‐ and postimplantation mammalian development. Recent studies have indicated that nuclear architecture provides an additional level of regulation, which needs to be explored in order to understand how a fertilised egg is able to develop into a full organism. Studies of 3D preserved nuclei of IVF preimplantation embryos from different mammalian species, such as mouse, rabbit and cow, have demonstrated that nuclear architecture undergoes major changes during early development. Both similarities and species‐specific differences were observed. Nuclear transfer experiments demonstrated changes of nuclear phenotypes, which to some extent reflect changes seen in IVF preimplantation embryos albeit with a different timing compared with IVF embryos. The dynamics of nuclear architecture is further substantiated by major changes during postmitotic terminal cell differentiation. Recent breakthroughs of 3D fluorescence microscopy with resolution beyond the conventional Abbe limit in combination with 3D electron microscopy provide the potential to explore the topography of nuclear structure with unprecedented resolution and detail.
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Grant J, Verrill C, Coustham V, Arneodo A, Palladino F, Monier K, Khalil A. Perinuclear distribution of heterochromatin in developing C. elegans embryos. Chromosome Res 2010; 18:873-85. [PMID: 21116703 DOI: 10.1007/s10577-010-9175-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2010] [Accepted: 11/16/2010] [Indexed: 10/18/2022]
Abstract
Specific nuclear domains are nonrandomly positioned within the nuclear space, and this preferential positioning has been shown to play an important role in genome activity and stability. Well-known examples include the organization of repetitive DNA in telomere clusters or in the chromocenter of Drosophila and mammalian cells, which may provide a means to control the availability of general repressors, such as the heterochromatin protein 1 (HP1). We have specifically characterized the intranuclear positioning of in vivo fluorescence of the Caenorhabditis elegans HP1 homologue HPL-2 as a marker for heterochromatin domains in developing embryos. For this purpose, the wavelet transform modulus maxima (WTMM) segmentation method was generalized and adapted to segment the small embryonic cell nuclei in three dimensions. The implementation of a radial distribution algorithm revealed a preferential perinuclear positioning of HPL-2 fluorescence in wild-type embryos compared with the diffuse and homogeneous nuclear fluorescence observed in the lin-13 mutants. For all other genotypes analyzed, the quantitative analysis highlighted various degrees of preferential HPL-2 positioning at the nuclear periphery, which directly correlates with the number of HPL-2 foci previously counted on 2D projections. Using a probabilistic 3D cell nuclear model, we found that any two nuclei having the same number of foci, but with a different 3D probabilistic positioning scheme, can have significantly different counts in the 2D maximum projection, thus showing the deceptive limitations of using techniques of 2D maximum projection foci counts. By this approach, a strong perinuclear positioning of HPL-2 foci was brought into light upon inactivation of conserved chromatin-associated proteins, including the HAT cofactor TRAPP.
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Affiliation(s)
- Jeremy Grant
- Department of Mathematics and Statistics, University of Maine, Orono, ME 04469, USA
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Abstract
The nuclear lamins are type V intermediate filament proteins that are critically important for the structural properties of the nucleus. In addition, they are involved in the regulation of numerous nuclear processes, including DNA replication, transcription and chromatin organization. The developmentally regulated expression of lamins suggests that they are involved in cellular differentiation. Their assembly dynamic properties throughout the cell cycle, particularly in mitosis, are influenced by posttranslational modifications. Lamins may regulate nuclear functions by direct interactions with chromatin and determining the spatial organization of chromosomes within the nuclear space. They may also regulate chromatin functions by interacting with factors that epigenetically modify the chromatin or directly regulate replication or transcription.
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Affiliation(s)
- Thomas Dechat
- Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
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48
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Andrey P, Kiêu K, Kress C, Lehmann G, Tirichine L, Liu Z, Biot E, Adenot PG, Hue-Beauvais C, Houba-Hérin N, Duranthon V, Devinoy E, Beaujean N, Gaudin V, Maurin Y, Debey P. Statistical analysis of 3D images detects regular spatial distributions of centromeres and chromocenters in animal and plant nuclei. PLoS Comput Biol 2010; 6:e1000853. [PMID: 20628576 PMCID: PMC2900307 DOI: 10.1371/journal.pcbi.1000853] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Accepted: 06/03/2010] [Indexed: 12/16/2022] Open
Abstract
In eukaryotes, the interphase nucleus is organized in morphologically and/or functionally distinct nuclear "compartments". Numerous studies highlight functional relationships between the spatial organization of the nucleus and gene regulation. This raises the question of whether nuclear organization principles exist and, if so, whether they are identical in the animal and plant kingdoms. We addressed this issue through the investigation of the three-dimensional distribution of the centromeres and chromocenters. We investigated five very diverse populations of interphase nuclei at different differentiation stages in their physiological environment, belonging to rabbit embryos at the 8-cell and blastocyst stages, differentiated rabbit mammary epithelial cells during lactation, and differentiated cells of Arabidopsis thaliana plantlets. We developed new tools based on the processing of confocal images and a new statistical approach based on G- and F- distance functions used in spatial statistics. Our original computational scheme takes into account both size and shape variability by comparing, for each nucleus, the observed distribution against a reference distribution estimated by Monte-Carlo sampling over the same nucleus. This implicit normalization allowed similar data processing and extraction of rules in the five differentiated nuclei populations of the three studied biological systems, despite differences in chromosome number, genome organization and heterochromatin content. We showed that centromeres/chromocenters form significantly more regularly spaced patterns than expected under a completely random situation, suggesting that repulsive constraints or spatial inhomogeneities underlay the spatial organization of heterochromatic compartments. The proposed technique should be useful for identifying further spatial features in a wide range of cell types.
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Affiliation(s)
- Philippe Andrey
- INRA, UMR1197 Neurobiologie de l'Olfaction et de la Prise Alimentaire, Jouy-en-Josas, France
- Université Paris-Sud 11, UMR 1197, Orsay, France
- IFR144 Neuro-Sud Paris, France
- UPMC, Université Paris 06, France
| | - Kiên Kiêu
- INRA, UR341, Mathématiques et Informatique Appliquées, Jouy-en-Josas, France
| | - Clémence Kress
- INRA, UR1196 Génomique et Physiologie de la Lactation, Jouy-en-Josas, France
| | - Gaëtan Lehmann
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
| | - Leïla Tirichine
- INRA, Institut J.-P. Bourgin, UMR1318 INRA-AgroParisTech, Versailles, France
| | - Zichuan Liu
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
| | - Eric Biot
- INRA, UMR1197 Neurobiologie de l'Olfaction et de la Prise Alimentaire, Jouy-en-Josas, France
- Université Paris-Sud 11, UMR 1197, Orsay, France
- IFR144 Neuro-Sud Paris, France
- INRA, Institut J.-P. Bourgin, UMR1318 INRA-AgroParisTech, Versailles, France
| | - Pierre-Gaël Adenot
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
| | - Cathy Hue-Beauvais
- INRA, UR1196 Génomique et Physiologie de la Lactation, Jouy-en-Josas, France
| | - Nicole Houba-Hérin
- INRA, Institut J.-P. Bourgin, UMR1318 INRA-AgroParisTech, Versailles, France
| | - Véronique Duranthon
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
| | - Eve Devinoy
- INRA, UR1196 Génomique et Physiologie de la Lactation, Jouy-en-Josas, France
| | - Nathalie Beaujean
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
| | - Valérie Gaudin
- INRA, Institut J.-P. Bourgin, UMR1318 INRA-AgroParisTech, Versailles, France
| | - Yves Maurin
- INRA, UMR1197 Neurobiologie de l'Olfaction et de la Prise Alimentaire, Jouy-en-Josas, France
- Université Paris-Sud 11, UMR 1197, Orsay, France
- IFR144 Neuro-Sud Paris, France
| | - Pascale Debey
- INRA, UMR1198 Biologie du Développement et Reproduction, Jouy-en-Josas, France
- ENVA, Maisons Alfort, France
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Rouquette J, Cremer C, Cremer T, Fakan S. Functional nuclear architecture studied by microscopy: present and future. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2010; 282:1-90. [PMID: 20630466 DOI: 10.1016/s1937-6448(10)82001-5] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In this review we describe major contributions of light and electron microscopic approaches to the present understanding of functional nuclear architecture. The large gap of knowledge, which must still be bridged from the molecular level to the level of higher order structure, is emphasized by differences of currently discussed models of nuclear architecture. Molecular biological tools represent new means for the multicolor visualization of various nuclear components in living cells. New achievements offer the possibility to surpass the resolution limit of conventional light microscopy down to the nanometer scale and require improved bioinformatics tools able to handle the analysis of large amounts of data. In combination with the much higher resolution of electron microscopic methods, including ultrastructural cytochemistry, correlative microscopy of the same cells in their living and fixed state is the approach of choice to combine the advantages of different techniques. This will make possible future analyses of cell type- and species-specific differences of nuclear architecture in more detail and to put different models to critical tests.
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Affiliation(s)
- Jacques Rouquette
- Biocenter, Ludwig Maximilians University (LMU), Martinsried, Germany
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Strickfaden H, Zunhammer A, van Koningsbruggen S, Köhler D, Cremer T. 4D chromatin dynamics in cycling cells: Theodor Boveri's hypotheses revisited. Nucleus 2010; 1:284-97. [PMID: 21327076 DOI: 10.4161/nucl.1.3.11969] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Revised: 04/02/2010] [Accepted: 04/06/2010] [Indexed: 01/14/2023] Open
Abstract
This live cell study of chromatin dynamics in four dimensions (space and time) in cycling human cells provides direct evidence for three hypotheses first proposed by Theodor Boveri in seminal studies of fixed blastomeres from Parascaris equorum embryos: (I) Chromosome territory (CT) arrangements are stably maintained during interphase. (II) Chromosome proximity patterns change profoundly during prometaphase. (III) Similar CT proximity patterns in pairs of daughter nuclei reflect symmetrical chromosomal movements during anaphase and telophase, but differ substantially from the arrangement in mother cell nucleus. Hypothesis I could be confirmed for the majority of interphase cells. A minority, however, showed complex, rotational movements of CT assemblies with large-scale changes of CT proximity patterns, while radial nuclear arrangements were maintained. A new model of chromatin dynamics is proposed. It suggests that long-range DNA-DNA interactions in cell nuclei may depend on a combination of rotational CT movements and locally constrained chromatin movements.
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Affiliation(s)
- Hilmar Strickfaden
- Department Biology II (Anthropology and Human Genetics), LMU Biozentrum, Martinsried, Germany
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