1
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García Fernández F, Huet S, Miné-Hattab J. Multi-Scale Imaging of the Dynamic Organization of Chromatin. Int J Mol Sci 2023; 24:15975. [PMID: 37958958 PMCID: PMC10649806 DOI: 10.3390/ijms242115975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/27/2023] [Accepted: 10/27/2023] [Indexed: 11/15/2023] Open
Abstract
Chromatin is now regarded as a heterogeneous and dynamic structure occupying a non-random position within the cell nucleus, where it plays a key role in regulating various functions of the genome. This current view of chromatin has emerged thanks to high spatiotemporal resolution imaging, among other new technologies developed in the last decade. In addition to challenging early assumptions of chromatin being regular and static, high spatiotemporal resolution imaging made it possible to visualize and characterize different chromatin structures such as clutches, domains and compartments. More specifically, super-resolution microscopy facilitates the study of different cellular processes at a nucleosome scale, providing a multi-scale view of chromatin behavior within the nucleus in different environments. In this review, we describe recent imaging techniques to study the dynamic organization of chromatin at high spatiotemporal resolution. We also discuss recent findings, elucidated by these techniques, on the chromatin landscape during different cellular processes, with an emphasis on the DNA damage response.
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Affiliation(s)
- Fabiola García Fernández
- Laboratory of Computational and Quantitative Biology, CNRS, Institut de Biologie Paris-Seine, Sorbonne Université, 75005 Paris, France;
| | - Sébastien Huet
- Univ Rennes, CNRS, IGDR (Institut de Génétique et Développement de Rennes)-UMR 6290, BIOSIT-UMS 3480, 35000 Rennes, France;
- Institut Universitaire de France, 75231 Paris, France
| | - Judith Miné-Hattab
- Laboratory of Computational and Quantitative Biology, CNRS, Institut de Biologie Paris-Seine, Sorbonne Université, 75005 Paris, France;
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2
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Rajshekar S, Adame-Arana O, Bajpai G, Lin K, Colmenares S, Safran S, Karpen GH. Affinity hierarchies and amphiphilic proteins underlie the co-assembly of nucleolar and heterochromatin condensates. RESEARCH SQUARE 2023:rs.3.rs-3385692. [PMID: 37841837 PMCID: PMC10571612 DOI: 10.21203/rs.3.rs-3385692/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
Nucleoli are surrounded by Pericentromeric Heterochromatin (PCH), reflecting a close spatial association between the two largest biomolecular condensates in eukaryotic nuclei. This nuclear organizational feature is highly conserved and is disrupted in diseased states like senescence, however, the mechanisms driving PCH-nucleolar association are unclear. High-resolution live imaging during early Drosophila development revealed a highly dynamic process in which PCH and nucleolar formation is coordinated and interdependent. When nucleolus assembly was eliminated by deleting the ribosomal RNA genes (rDNA), PCH showed increased compaction and subsequent reorganization to a shell-like structure. In addition, in embryos lacking rDNA, some nucleolar proteins were redistributed into new bodies or 'neocondensates,' including enrichment in the core of the PCH shell. These observations, combined with physical modeling and simulations, suggested that nucleolar-PCH associations are mediated by a hierarchy of affinities between PCH, nucleoli, and 'amphiphilic' protein(s) that interact with both nucleolar and PCH components. This result was validated by demonstrating that the depletion of one candidate amphiphile, the nucleolar protein Pitchoune, significantly reduced PCH-nucleolar associations. Together, these results unveil a dynamic program for establishing nucleolar-PCH associations during animal development, demonstrate that nucleoli are required for normal PCH organization, and identify Pitchoune as an amphiphilic molecular link that promotes PCH-nucleolar associations. Finally, we propose that disrupting affinity hierarchies between interacting condensates can liberate molecules to form neocondensates or other aberrant structures that could contribute to cellular disease phenotypes.
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Affiliation(s)
- Srivarsha Rajshekar
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, USA
| | - Omar Adame-Arana
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Gaurav Bajpai
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Kyle Lin
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, USA
| | - Serafin Colmenares
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, USA
| | - Samuel Safran
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Gary H Karpen
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, USA
- Division of Biological Sciences and the Environment, Lawrence Berkeley National Laboratory, Berkeley, USA
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3
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Melters DP, Neuman KC, Bentahar RS, Rakshit T, Dalal Y. Single molecule analysis of CENP-A chromatin by high-speed atomic force microscopy. eLife 2023; 12:e86709. [PMID: 37728600 PMCID: PMC10511241 DOI: 10.7554/elife.86709] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 09/01/2023] [Indexed: 09/21/2023] Open
Abstract
Chromatin accessibility is modulated in a variety of ways to create open and closed chromatin states, both of which are critical for eukaryotic gene regulation. At the single molecule level, how accessibility is regulated of the chromatin fiber composed of canonical or variant nucleosomes is a fundamental question in the field. Here, we developed a single-molecule tracking method where we could analyze thousands of canonical H3 and centromeric variant nucleosomes imaged by high-speed atomic force microscopy. This approach allowed us to investigate how changes in nucleosome dynamics in vitro inform us about transcriptional potential in vivo. By high-speed atomic force microscopy, we tracked chromatin dynamics in real time and determined the mean square displacement and diffusion constant for the variant centromeric CENP-A nucleosome. Furthermore, we found that an essential kinetochore protein CENP-C reduces the diffusion constant and mobility of centromeric nucleosomes along the chromatin fiber. We subsequently interrogated how CENP-C modulates CENP-A chromatin dynamics in vivo. Overexpressing CENP-C resulted in reduced centromeric transcription and impaired loading of new CENP-A molecules. From these data, we speculate that factors altering nucleosome mobility in vitro, also correspondingly alter transcription in vivo. Subsequently, we propose a model in which variant nucleosomes encode their own diffusion kinetics and mobility, and where binding partners can suppress or enhance nucleosome mobility.
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Affiliation(s)
- Daniël P Melters
- National Cancer Institute, Center for Cancer Research, Laboratory Receptor Biology and Gene ExpressionBethesdaUnited States
| | - Keir C Neuman
- National Heart, Lung, and Blood Institute, Laboratory of Single Molecule BiophysicsBethesdaUnited States
| | - Reda S Bentahar
- National Cancer Institute, Center for Cancer Research, Laboratory Receptor Biology and Gene ExpressionBethesdaUnited States
| | - Tatini Rakshit
- National Cancer Institute, Center for Cancer Research, Laboratory Receptor Biology and Gene ExpressionBethesdaUnited States
- Department of Chemistry, Shiv Nadar UniversityDadriIndia
| | - Yamini Dalal
- National Cancer Institute, Center for Cancer Research, Laboratory Receptor Biology and Gene ExpressionBethesdaUnited States
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4
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Chen Q, Zhao L, Soman A, Arkhipova AY, Li J, Li H, Chen Y, Shi X, Nordenskiöld L. Chromatin Liquid-Liquid Phase Separation (LLPS) Is Regulated by Ionic Conditions and Fiber Length. Cells 2022; 11:cells11193145. [PMID: 36231107 PMCID: PMC9564186 DOI: 10.3390/cells11193145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/20/2022] [Accepted: 10/02/2022] [Indexed: 11/16/2022] Open
Abstract
The dynamic regulation of the physical states of chromatin in the cell nucleus is crucial for maintaining cellular homeostasis. Chromatin can exist in solid- or liquid-like forms depending on the surrounding ions, binding proteins, post-translational modifications and many other factors. Several recent studies suggested that chromatin undergoes liquid-liquid phase separation (LLPS) in vitro and also in vivo; yet, controversial conclusions about the nature of chromatin LLPS were also observed from the in vitro studies. These inconsistencies are partially due to deviations in the in vitro buffer conditions that induce the condensation/aggregation of chromatin as well as to differences in chromatin (nucleosome array) constructs used in the studies. In this work, we present a detailed characterization of the effects of K+, Mg2+ and nucleosome fiber length on the physical state and property of reconstituted nucleosome arrays. LLPS was generally observed for shorter nucleosome arrays (15-197-601, reconstituted from 15 repeats of the Widom 601 DNA with 197 bp nucleosome repeat length) at physiological ion concentrations. In contrast, gel- or solid-like condensates were detected for the considerably longer 62-202-601 and lambda DNA (~48.5 kbp) nucleosome arrays under the same conditions. In addition, we demonstrated that the presence of reduced BSA and acetate buffer is not essential for the chromatin LLPS process. Overall, this study provides a comprehensive understanding of several factors regarding chromatin physical states and sheds light on the mechanism and biological relevance of chromatin phase separation in vivo.
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Affiliation(s)
- Qinming Chen
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
| | - Lei Zhao
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Aghil Soman
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
| | - Anastasia Yu Arkhipova
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
- Biological Faculty, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Jindi Li
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Hao Li
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Yinglu Chen
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
| | - Xiangyan Shi
- Department of Biology, Shenzhen MSU-BIT University, Shenzhen 518172, China; (L.Z.); (A.Y.A.); (J.L.); (H.L.); (Y.C.)
- Correspondence: (X.S.); (L.N.)
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; (Q.C.); (A.S.)
- Correspondence: (X.S.); (L.N.)
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5
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Liu W, Padhi A, Zhang X, Narendran J, Anastasio MA, Nain AS, Irudayaraj J. Dynamic Heterochromatin States in Anisotropic Nuclei of Cells on Aligned Nanofibers. ACS NANO 2022; 16:10754-10767. [PMID: 35803582 PMCID: PMC9332347 DOI: 10.1021/acsnano.2c02660] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The cancer cell nucleus deforms as it invades the interstitial spaces in tissues and the tumor microenvironment. While alteration of the chromatin structure in a deformed nucleus is expected and documented, the chromatin structure in the nuclei of cells on aligned matrices has not been elucidated. In this work we elucidate the spatiotemporal organization of heterochromatin in the elongated nuclei of cells on aligned nanofibers with stimulated emission depletion nanoscopy and fluorescence correlation spectroscopy. We show that the anisotropy of nuclei is sufficient to drive H3K9me3-heterochromatin alterations, with enhanced H3K9me3 nanocluster compaction and aggregation states that otherwise are indistinguishable from diffraction-limited microscopy. We interrogated the higher-order heterochromatin structures within major chromatin compartments in anisotropic nuclei and discovered a wider spatial dispersion of nanodomain clusters in the nucleoplasm and condensed larger nanoclusters near the periphery and pericentromeric heterochromatin. Upon examining the spatiotemporal dynamics of heterochromatin in anisotropic nuclei, we observed reduced mobility of the constitutive heterochromatin mark H3K9me3 and the associated heterochromatin protein 1 (HP1α) at the nucleoplasm and periphery regions, correlating with increased viscosity and changes in gene expression. Since heterochromatin remodeling is crucial to genome integrity, our results reveal an unconventional H3K9me3 heterochromatin distribution, providing cues to an altered chromatin state due to perturbations of the nuclei in aligned fiber configurations.
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Affiliation(s)
- Wenjie Liu
- Department
of Bioengineering, University of Illinois
at Urbana−Champaign, 1102 Everitt Lab, 1406 W. Green Street, Urbana, Illinois 61801, United States
- Biomedical
Research Center, Mills Breast Cancer Institute, Cancer Center at Illinois,
Micro and Nanotechnology Laboratory, Beckman
Institute, Carl Woese Institute for Genomic Biology, Urbana, Illinois 61801, United States
| | - Abinash Padhi
- Department
of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Xiaohui Zhang
- Department
of Bioengineering, University of Illinois
at Urbana−Champaign, 1102 Everitt Lab, 1406 W. Green Street, Urbana, Illinois 61801, United States
| | - Jairaj Narendran
- Department
of Bioengineering, University of Illinois
at Urbana−Champaign, 1102 Everitt Lab, 1406 W. Green Street, Urbana, Illinois 61801, United States
| | - Mark A. Anastasio
- Department
of Bioengineering, University of Illinois
at Urbana−Champaign, 1102 Everitt Lab, 1406 W. Green Street, Urbana, Illinois 61801, United States
| | - Amrinder S. Nain
- Department
of Mechanical Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Joseph Irudayaraj
- Department
of Bioengineering, University of Illinois
at Urbana−Champaign, 1102 Everitt Lab, 1406 W. Green Street, Urbana, Illinois 61801, United States
- Biomedical
Research Center, Mills Breast Cancer Institute, Cancer Center at Illinois,
Micro and Nanotechnology Laboratory, Beckman
Institute, Carl Woese Institute for Genomic Biology, Urbana, Illinois 61801, United States
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6
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Williams MR, Xiaokang Y, Hathaway NA, Kireev D. A simulation model of heterochromatin formation at submolecular detail. iScience 2022; 25:104590. [PMID: 35800764 PMCID: PMC9254115 DOI: 10.1016/j.isci.2022.104590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 11/16/2021] [Accepted: 06/08/2022] [Indexed: 11/15/2022] Open
Abstract
Heterochromatin is a physical state of the chromatin fiber that maintains gene repression during cell development. Although evidence exists on molecular mechanisms involved in heterochromatin formation, a detailed structural mechanism of heterochromatin formation needs a better understanding. We made use of a simple Monte Carlo simulation model with explicit representation of key molecular events to observe molecular self-organization leading to heterochromatin formation. Our simulations provide a structural interpretation of several important traits of the heterochromatinization process. In particular, this study provides a depiction of how small amounts of HP1 are able to induce a highly condensed chromatin state through HP1 dimerization and bridging of sequence-remote nucleosomes. It also elucidates structural roots of a yet poorly understood phenomenon of a nondeterministic nature of heterochromatin formation and subsequent gene repression. Experimental chromatin in vivo assay provides an unbiased estimate of time scale of repressive response to a heterochromatin-triggering event.
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Affiliation(s)
- Michael R. Williams
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
| | - Yan Xiaokang
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Nathaniel A. Hathaway
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, Chapel Hill, NC 27599, USA
| | - Dmitri Kireev
- Center for Integrative Chemical Biology and Drug Discovery, University of North Carolina, Chapel Hill, NC 27513, USA
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
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7
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Abstract
In eukaryotic cells, protein and RNA factors involved in genome activities like transcription, RNA processing, DNA replication, and repair accumulate in self-organizing membraneless chromatin subcompartments. These structures contribute to efficiently conduct chromatin-mediated reactions and to establish specific cellular programs. However, the underlying mechanisms for their formation are only partly understood. Recent studies invoke liquid-liquid phase separation (LLPS) of proteins and RNAs in the establishment of chromatin activity patterns. At the same time, the folding of chromatin in the nucleus can drive genome partitioning into spatially distinct domains. Here, the interplay between chromatin organization, chromatin binding, and LLPS is discussed by comparing and contrasting three prototypical chromatin subcompartments: the nucleolus, clusters of active RNA polymerase II, and pericentric heterochromatin domains. It is discussed how the different ways of chromatin compartmentalization are linked to transcription regulation, the targeting of soluble factors to certain parts of the genome, and to disease-causing genetic aberrations.
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Affiliation(s)
- Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, 69120 Heidelberg, Germany
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8
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Hausmann M, Hildenbrand G, Pilarczyk G. Networks and Islands of Genome Nano-architecture and Their Potential Relevance for Radiation Biology : (A Hypothesis and Experimental Verification Hints). Results Probl Cell Differ 2022; 70:3-34. [PMID: 36348103 DOI: 10.1007/978-3-031-06573-6_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The cell nucleus is a complex biological system in which simultaneous reactions and functions take place to keep the cell as an individualized, specialized system running well. The cell nucleus contains chromatin packed in various degrees of density and separated in volumes of chromosome territories and subchromosomal domains. Between the chromatin, however, there is enough "free" space for floating RNA, proteins, enzymes, ATPs, ions, water molecules, etc. which are trafficking by super- and supra-diffusion to the interaction points where they are required. It seems that this trafficking works somehow automatically and drives the system perfectly. After exposure to ionizing radiation causing DNA damage from single base damage up to chromatin double-strand breaks, the whole system "cell nucleus" responds, and repair processes are starting to recover the fully functional and intact system. In molecular biology, many individual epigenetic pathways of DNA damage response or repair of single and double-strand breaks are described. How these responses are embedded into the response of the system as a whole is often out of the focus of consideration. In this article, we want to follow the hypothesis of chromatin architecture's impact on epigenetic pathways and vice versa. Based on the assumption that chromatin acts like an "aperiodic solid state within a limited volume," functionally determined networks and local topologies ("islands") can be defined that drive the appropriate repair process at a given damage site. Experimental results of investigations of the chromatin nano-architecture and DNA repair clusters obtained by means of single-molecule localization microscopy offer hints and perspectives that may contribute to verifying the hypothesis.
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Affiliation(s)
- Michael Hausmann
- Kirchhoff-Institute for Physics, Heidelberg University, Heidelberg, Germany.
| | - Georg Hildenbrand
- Kirchhoff-Institute for Physics, Heidelberg University, Heidelberg, Germany
| | - Götz Pilarczyk
- Kirchhoff-Institute for Physics, Heidelberg University, Heidelberg, Germany
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9
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Knoch TA. Simulation of Different Three-Dimensional Models of Whole Interphase Nuclei Compared to Experiments - A Consistent Scale-Bridging Simulation Framework for Genome Organization. Results Probl Cell Differ 2022; 70:495-549. [PMID: 36348120 DOI: 10.1007/978-3-031-06573-6_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The three-dimensional architecture of chromosomes, their arrangement, and dynamics within cell nuclei are still subject of debate. Obviously, the function of genomes-the storage, replication, and transcription of genetic information-has closely coevolved with this architecture and its dynamics, and hence are closely connected. In this work a scale-bridging framework investigates how of the 30 nm chromatin fibre organizes into chromosomes including their arrangement and morphology in the simulation of whole nuclei. Therefore, mainly two different topologies were simulated with corresponding parameter variations and comparing them to experiments: The Multi-Loop-Subcompartment (MLS) model, in which (stable) small loops form (stable) rosettes, connected by chromatin linkers, and the Random-Walk/Giant-Loop (RW/GL) model, in which large loops are attached to a flexible non-protein backbone, were simulated for various loop and linker sizes. The 30 nm chromatin fibre was modelled as a polymer chain with stretching, bending and excluded volume interactions. A spherical boundary potential simulated the confinement to nuclei with different radii. Simulated annealing and Brownian Dynamics methods were applied in a four-step decondensation procedure to generate from metaphase decondensated interphase configurations at thermodynamical equilibrium. Both the MLS and the RW/GL models form chromosome territories, with different morphologies: The MLS rosettes result in distinct subchromosomal domains visible in electron and confocal laser scanning microscopic images. In contrast, the big RW/GL loops lead to a mostly homogeneous chromatin distribution. Even small changes of the model parameters induced significant rearrangements of the chromatin morphology. The low overlap of chromosomes, arms, and subchromosomal domains observed in experiments agrees only with the MLS model. The chromatin density distribution in CLSM image stacks reveals a bimodal behaviour in agreement with recent experiments. Combination of these results with a variety of (spatial distance) measurements favour an MLS like model with loops and linkers of 63 to 126 kbp. The predicted large spaces between the chromatin fibres allow typically sized biological molecules to reach nearly every location in the nucleus by moderately obstructed diffusion and is in disagreement with the much simplified assumption that defined channels between territories for molecular transport as in the Interchromosomal Domain (ICD) hypothesis exist and are necessary for transport. All this is also in agreement with recent selective high-resolution chromosome interaction capture (T2C) experiments, the scaling behaviour of the DNA sequence, the dynamics of the chromatin fibre, the diffusion of molecules, and other measurements. Also all other chromosome topologies can in principle be excluded. In summary, polymer simulations of whole nuclei compared to experimental data not only clearly favour only a stable loop aggregate/rosette like genome architecture whose local topology is tightly connected to the global morphology and dynamics of the cell nucleus and hence can be used for understanding genome organization also in respect to diagnosis and treatment. This is in agreement with and also leads to a general novel framework of genome emergence, function, and evolution.
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Affiliation(s)
- Tobias A Knoch
- Biophysical Genomics, TAKnoch Joined Operations Administrative Office, Mannheim, Germany.
- Human Ecology and Complex Systems, German Society for Human Ecology (DGH), TAKnoch Joined Operations Administrative Office, Mannheim, Germany.
- TAK Renewable Energy UG, TAKnoch Joined Operations Administrative Office, Mannheim, Germany.
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10
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Tsuchiya M, Giuliani A, Zimatore G, Erenpreisa J, Yoshikawa K. A Unified Genomic Mechanism of Cell-Fate Change. Results Probl Cell Differ 2022; 70:35-69. [PMID: 36348104 DOI: 10.1007/978-3-031-06573-6_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The purpose of our studies is to elucidate the nature of massive control of the whole genome expression with a particular emphasis on cell-fate change. The whole genome expression is coordinated by the emergence of a critical point (CP: a peculiar set of biphasic genes) with the genome acting as an integrated dynamical system. In response to stimuli, the genome expression self-organizes into local sub-, near-, and super-critical states, each exhibiting distinct collective behaviors with its center of mass acting as a local attractor, coexisting with the whole genome attractor (GA). The CP serves as the organizing center of cell-fate change, and its activation makes local perturbation to spread over the genome affecting GA. The activation of CP is in turn elicited by genes with elevated temporal variance (oscillating-mode genes), normally in charge to keep genome expression at pace with microenvironment fluctuations. When oscillation exceeds a given threshold, the CP synchronizes with the GA driving genome expression state transition. The expression synchronization wave invading the entire genome is fostered by the fusion-splitting dynamics of silencing pericentromere-associated heterochromatin domains and the consequent folding-unfolding transitions of transcribing euchromatin domains. The proposed mechanism is a unified step toward a time-evolutional transition theory of biological regulation.
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Affiliation(s)
- Masa Tsuchiya
- SEIKO Life Science Laboratory, SEIKO Research Institute for Education, Osaka, Japan.
| | - Alessandro Giuliani
- Environment and Health Department, Istituto Superiore di Sanitá, Rome, Italy.
| | | | | | - Kenichi Yoshikawa
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
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11
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Maslova A, Krasikova A. FISH Going Meso-Scale: A Microscopic Search for Chromatin Domains. Front Cell Dev Biol 2021; 9:753097. [PMID: 34805161 PMCID: PMC8597843 DOI: 10.3389/fcell.2021.753097] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Accepted: 10/08/2021] [Indexed: 12/14/2022] Open
Abstract
The intimate relationships between genome structure and function direct efforts toward deciphering three-dimensional chromatin organization within the interphase nuclei at different genomic length scales. For decades, major insights into chromatin structure at the level of large-scale euchromatin and heterochromatin compartments, chromosome territories, and subchromosomal regions resulted from the evolution of light microscopy and fluorescence in situ hybridization. Studies of nanoscale nucleosomal chromatin organization benefited from a variety of electron microscopy techniques. Recent breakthroughs in the investigation of mesoscale chromatin structures have emerged from chromatin conformation capture methods (C-methods). Chromatin has been found to form hierarchical domains with high frequency of local interactions from loop domains to topologically associating domains and compartments. During the last decade, advances in super-resolution light microscopy made these levels of chromatin folding amenable for microscopic examination. Here we are reviewing recent developments in FISH-based approaches for detection, quantitative measurements, and validation of contact chromatin domains deduced from C-based data. We specifically focus on the design and application of Oligopaint probes, which marked the latest progress in the imaging of chromatin domains. Vivid examples of chromatin domain FISH-visualization by means of conventional, super-resolution light and electron microscopy in different model organisms are provided.
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Affiliation(s)
| | - Alla Krasikova
- Laboratory of Nuclear Structure and Dynamics, Cytology and Histology Department, Saint Petersburg State University, Saint Petersburg, Russia
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12
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Nussinov R, Zhang M, Maloney R, Jang H. Ras isoform-specific expression, chromatin accessibility, and signaling. Biophys Rev 2021; 13:489-505. [PMID: 34466166 PMCID: PMC8355297 DOI: 10.1007/s12551-021-00817-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/29/2021] [Indexed: 12/12/2022] Open
Abstract
The anchorage of Ras isoforms in the membrane and their nanocluster formations have been studied extensively, including their detailed interactions, sizes, preferred membrane environments, chemistry, and geometry. However, the staggering challenge of their epigenetics and chromatin accessibility in distinct cell states and types, which we propose is a major factor determining their specific expression, still awaits unraveling. Ras isoforms are distinguished by their C-terminal hypervariable region (HVR) which acts in intracellular transport, regulation, and membrane anchorage. Here, we review some isoform-specific activities at the plasma membrane from a structural dynamic standpoint. Inspired by physics and chemistry, we recognize that understanding functional specificity requires insight into how biomolecules can organize themselves in different cellular environments. Within this framework, we suggest that isoform-specific expression may largely be controlled by the chromatin density and physical compaction, which allow (or curb) access to "chromatinized DNA." Genes are preferentially expressed in tissues: proteins expressed in pancreatic cells may not be equally expressed in lung cells. It is the rule-not an exception, and it can be at least partly understood in terms of chromatin organization and accessibility state. Genes are expressed when they can be sufficiently exposed to the transcription machinery, and they are less so when they are persistently buried in dense chromatin. Notably, chromatin accessibility can similarly determine expression of drug resistance genes.
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Affiliation(s)
- Ruth Nussinov
- Computational Structural Biology Section Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism National Cancer Institute, 1050 Boyles St, Frederick, MD 21702 USA
- Department of Human Molecular Genetics and Biochemistry, Sackler School of Medicine Tel Aviv University, 69978 Tel Aviv, Israel
| | - Mingzhen Zhang
- Computational Structural Biology Section Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism National Cancer Institute, 1050 Boyles St, Frederick, MD 21702 USA
| | - Ryan Maloney
- Computational Structural Biology Section Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism National Cancer Institute, 1050 Boyles St, Frederick, MD 21702 USA
| | - Hyunbum Jang
- Computational Structural Biology Section Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research in the Laboratory of Cancer Immunometabolism National Cancer Institute, 1050 Boyles St, Frederick, MD 21702 USA
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13
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Basak R, Rosencrans W, Yadav I, Yan P, Berezhnoy NV, Chen Q, van Kan JA, Nordenskiöld L, Zinchenko A, van der Maarel JRC. Internal Motion of Chromatin Fibers Is Governed by Dynamics of Uncompressed Linker Strands. Biophys J 2020; 119:2326-2334. [PMID: 33121944 PMCID: PMC7732777 DOI: 10.1016/j.bpj.2020.10.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/23/2020] [Accepted: 10/13/2020] [Indexed: 11/25/2022] Open
Abstract
Chromatin compaction and internal motion are fundamental aspects of gene expression regulation. Here, we have investigated chromatin fibers comprising recombinant histone octamers reconstituted with double-stranded bacteriophage T4-DNA. The size of the fibers approaches the typical size of genomic topologically associated domains. Atomic force and fluorescence (correlation) microscopy have been used to assess the structural organization, histone-induced compaction, and internal motion. In particular, the fibers are stretched on arrays of nanochannels, each channel with a diameter of 60 or 125 nm. Major intrafiber segregation and fast internal fluctuations are observed. Full compaction was only achieved by triggering an attractive nucleosome interaction through the addition of magnesium cations. Besides compaction, histone complexation results in a dramatic decrease in the fiber's relaxation time. The relaxation times are similar to those of naked DNA with a comparable stretch, which indicates that internal motion is governed by the dynamics of uncompressed linker strands. Furthermore, the main reorganization process is association-dissociation of individually compacted regions. We surmise that the modulation of chromatin's internal motion by histone complexation might have implications for transcriptional bursting.
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Affiliation(s)
- Rajib Basak
- Department of Physics, National University of Singapore, Singapore, Republic of Singapore
| | - William Rosencrans
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Indresh Yadav
- Department of Physics, National University of Singapore, Singapore, Republic of Singapore
| | - Peiyan Yan
- Department of Physics, National University of Singapore, Singapore, Republic of Singapore
| | - Nikolay V Berezhnoy
- School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore
| | - Qinming Chen
- School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore
| | - Jeroen A van Kan
- Department of Physics, National University of Singapore, Singapore, Republic of Singapore
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, Singapore, Republic of Singapore
| | - Anatoly Zinchenko
- Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
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14
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Cremer T, Cremer M, Hübner B, Silahtaroglu A, Hendzel M, Lanctôt C, Strickfaden H, Cremer C. The Interchromatin Compartment Participates in the Structural and Functional Organization of the Cell Nucleus. Bioessays 2020; 42:e1900132. [PMID: 31994771 DOI: 10.1002/bies.201900132] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 11/24/2019] [Indexed: 12/11/2022]
Abstract
This article focuses on the role of the interchromatin compartment (IC) in shaping nuclear landscapes. The IC is connected with nuclear pore complexes (NPCs) and harbors splicing speckles and nuclear bodies. It is postulated that the IC provides routes for imported transcription factors to target sites, for export routes of mRNA as ribonucleoproteins toward NPCs, as well as for the intranuclear passage of regulatory RNAs from sites of transcription to remote functional sites (IC hypothesis). IC channels are lined by less-compacted euchromatin, called the perichromatin region (PR). The PR and IC together form the active nuclear compartment (ANC). The ANC is co-aligned with the inactive nuclear compartment (INC), comprising more compacted heterochromatin. It is postulated that the INC is accessible for individual transcription factors, but inaccessible for larger macromolecular aggregates (limited accessibility hypothesis). This functional nuclear organization depends on still unexplored movements of genes and regulatory sequences between the two compartments.
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Affiliation(s)
- Thomas Cremer
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Marion Cremer
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Barbara Hübner
- Anthropology and Human Genomics, Department of Biology II, Ludwig-Maximilians University (LMU), Biocenter, Grosshadernerstr. 2, 82152, Martinsried, Germany
| | - Asli Silahtaroglu
- Department of Cellular and Molecular Medicine Faculty of Health and Medical Sciences, University of Copenhagen, Nørre Alle 14, Byg.18.03, 2200, Copenhagen N, Denmark
| | - Michael Hendzel
- Department of Oncology, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, T6G 1Z2, Canada
| | - Christian Lanctôt
- Integration Santé, 1250 Avenue de la Station local 2-304, Shawinigan, Québec, G9N 8K9, Canada
| | - Hilmar Strickfaden
- Department of Oncology, Cross Cancer Institute, University of Alberta, 11560 University Avenue, Edmonton, Alberta, T6G 1Z2, Canada
| | - Christoph Cremer
- Institute of Molecular Biology (IMB) Ackermannweg 4, 55128 Mainz, Germany, and Institute of Pharmacy & Molecular Biotechnology (IPMB), University Heidelberg, Im Neuenheimer Feld 364, 69120, Heidelberg, Germany
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15
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Tsuchiya M, Giuliani A, Yoshikawa K. Cell-Fate Determination from Embryo to Cancer Development: Genomic Mechanism Elucidated. Int J Mol Sci 2020; 21:E4581. [PMID: 32605138 PMCID: PMC7369777 DOI: 10.3390/ijms21134581] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 06/12/2020] [Indexed: 12/12/2022] Open
Abstract
Elucidation of the genomic mechanism that guides the cell-fate change is one of the fundamental issues of biology. We previously demonstrated that whole genome expression is coordinated by the emergence of a critical point at both the cell-population and single-cell levels through the physical principle of self-organized criticality. In this paper, we further examine the genomic mechanism that determines the cell-fate changes from embryo to cancer development. The state of the critical point, acting as the organizing center of the cell fate, determines whether the genome resides in a super- or sub-critical state. In the super-critical state, a specific stochastic perturbation can spread over the entire system through the "genome engine", an autonomous critical-control genomic system, whereas in the sub-critical state, the perturbation remains at a local level. The cell-fate changes when the genome becomes super-critical. We provide a consistent framework to develop a time-evolutional transition theory for the biological regulation of the cell-fate change.
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Affiliation(s)
- Masa Tsuchiya
- SEIKO Life Science Laboratory, SRI, Osaka 540-659, Japan
| | - Alessandro Giuliani
- Environment and Health Department, Istituto Superiore di Sanitá, 00161 Rome, Italy;
| | - Kenichi Yoshikawa
- Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe 610-0394, Japan;
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16
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Übelmesser N, Papantonis A. Technologies to study spatial genome organization: beyond 3C. Brief Funct Genomics 2020; 18:395-401. [PMID: 31609405 DOI: 10.1093/bfgp/elz019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/27/2019] [Accepted: 07/15/2019] [Indexed: 01/05/2023] Open
Abstract
The way that chromatin is organized in three-dimensional nuclear space is now acknowledged as a factor critical for the major cell processes, like transcription, replication and cell division. Researchers have been armed with new molecular and imaging technologies to study this structure-to-function link of genomes, spearheaded by the introduction of the 'chromosome conformation capture' technology more than a decade ago. However, this technology is not without shortcomings, and novel variants and orthogonal approaches are being developed to overcome these. As a result, the field of nuclear organization is constantly fueled by methods of increasing resolution and/or throughput that strive to eliminate systematic biases and increase precision. In this review, we attempt to highlight the most recent advances in technology that promise to provide novel insights on how chromosomes fold and function.
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Affiliation(s)
- Nadine Übelmesser
- Institute of Pathology, University Medical Center Göttingen, 37075 Göttingen, Germany
| | - Argyris Papantonis
- Institute of Pathology, University Medical Center Göttingen, 37075 Göttingen, Germany
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17
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Zinchenko A, Chen Q, Berezhnoy NV, Wang S, Nordenskiöld L. Compaction and self-association of megabase-sized chromatin are induced by anionic protein crowding. SOFT MATTER 2020; 16:4366-4372. [PMID: 32253414 DOI: 10.1039/d0sm00162g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Highly compacted chromatin, a complex of DNA with cationic histone proteins, is found in the nucleus of eukaryotic cells in an environment with a high concentration of macromolecular species, many of which possess a negative charge. In the majority of previous studies, however, these crowding conditions were experimentally modelled using neutral synthetic macromolecules such as polyethylene glycol (PEG). Despite the importance of the crowding agent charge in the condensation process of chromatin, to the best of our knowledge, the behavior of chromatin under conditions of anionic protein crowding has not been studied. Here, compaction of nearly megabase-long chromatin in the presence of the anionic globular protein BSA was investigated by single-molecule fluorescent microscopy (FM). We demonstrate different effects of anionic macromolecular crowders (MMCs) on DNA and chromatin, compared to neutral MMCs. While DNA molecules undergo gradual compaction into a globular form in the presence of ca. 20% w/v of BSA, chromatin fibres complete coil to globule transition at a much lower concentration of BSA (ca. 5% w/v). Furthermore, at higher concentrations of BSA in solution (>5% w/v), chromatin fibres self-associate and form large spherical or fibrillar supramolecular microstructures characterized by a high colloidal stability and dynamic intermolecular fluctuations. Formation of such self-organized colloids from chromatin is universal and characteristic of chromatin fibres of various lengths. Our results highlight the hitherto underappreciated effect of anionic MMC environment on chromatin higher-order structures that may play an important role in self-organization of chromatin in vivo.
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Affiliation(s)
- Anatoly Zinchenko
- Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
| | - Qinming Chen
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore.
| | - Nikolay V Berezhnoy
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore.
| | - Sai Wang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore.
| | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551, Singapore.
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18
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Kochanova NY, Schauer T, Mathias GP, Lukacs A, Schmidt A, Flatley A, Schepers A, Thomae AW, Imhof A. A multi-layered structure of the interphase chromocenter revealed by proximity-based biotinylation. Nucleic Acids Res 2020; 48:4161-4178. [PMID: 32182352 PMCID: PMC7192626 DOI: 10.1093/nar/gkaa145] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/18/2020] [Accepted: 02/25/2020] [Indexed: 12/26/2022] Open
Abstract
During interphase centromeres often coalesce into a small number of chromocenters, which can be visualized as distinct, DAPI dense nuclear domains. Intact chromocenters play a major role in maintaining genome stability as they stabilize the transcriptionally silent state of repetitive DNA while ensuring centromere function. Despite its biological importance, relatively little is known about the molecular composition of the chromocenter or the processes that mediate chromocenter formation and maintenance. To provide a deeper molecular insight into the composition of the chromocenter and to demonstrate the usefulness of proximity-based biotinylation as a tool to investigate those questions, we performed super resolution microscopy and proximity-based biotinylation experiments of three distinct proteins associated with the chromocenter in Drosophila. Our work revealed an intricate internal architecture of the chromocenter suggesting a complex multilayered structure of this intranuclear domain.
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Affiliation(s)
- Natalia Y Kochanova
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Tamas Schauer
- Biomedical Center, Bioinformatics Core Facility, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Grusha Primal Mathias
- Biomedical Center, Core Facility Bioimaging, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andrea Lukacs
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andreas Schmidt
- Biomedical Center, Protein Analysis Unit, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Andrew Flatley
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility and Research Group Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Aloys Schepers
- Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility and Research Group Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Andreas W Thomae
- Biomedical Center, Core Facility Bioimaging, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
| | - Axel Imhof
- Biomedical Center, Chromatin Proteomics Group, Department of Molecular Biology, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
- Biomedical Center, Protein Analysis Unit, Faculty of Medicine, Ludwig-Maximilians-Universität München, Großhaderner Strasse 9, 82152 Planegg-Martinsried, Germany
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19
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Shaban HA, Barth R, Recoules L, Bystricky K. Hi-D: nanoscale mapping of nuclear dynamics in single living cells. Genome Biol 2020; 21:95. [PMID: 32312289 PMCID: PMC7168861 DOI: 10.1186/s13059-020-02002-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 03/20/2020] [Indexed: 02/06/2023] Open
Abstract
Bulk chromatin motion has not been analyzed at high resolution. We present Hi-D, a method to quantitatively map dynamics of chromatin and abundant nuclear proteins for every pixel simultaneously over the entire nucleus from fluorescence image series. Hi-D combines reconstruction of chromatin motion and classification of local diffusion processes by Bayesian inference. We show that DNA dynamics in the nuclear interior are spatially partitioned into 0.3-3-μm domains in a mosaic-like pattern, uncoupled from chromatin compaction. This pattern was remodeled in response to transcriptional activity. Hi-D can be applied to any dense and bulk structures opening new perspectives towards understanding motion of nuclear molecules.
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Affiliation(s)
- Haitham A Shaban
- Laboratoire de Biologie Moléculaire Eucaryote (LBME), Centre de Biologie Intégrative (CBI), CNRS, University of Toulouse, UPS, 31062, Toulouse, France.
- Spectroscopy Department, Physics Division, National Research Centre, 33 El Bohouth Str., P.O. 12622, Cairo, Egypt.
| | - Roman Barth
- Laboratoire de Biologie Moléculaire Eucaryote (LBME), Centre de Biologie Intégrative (CBI), CNRS, University of Toulouse, UPS, 31062, Toulouse, France
- Present Address: Bionanoscience Department, Faculty of Applied Sciences, Delft University of Technology, 2628 CJ, Delft, The Netherlands
| | - Ludmila Recoules
- Laboratoire de Biologie Moléculaire Eucaryote (LBME), Centre de Biologie Intégrative (CBI), CNRS, University of Toulouse, UPS, 31062, Toulouse, France
| | - Kerstin Bystricky
- Laboratoire de Biologie Moléculaire Eucaryote (LBME), Centre de Biologie Intégrative (CBI), CNRS, University of Toulouse, UPS, 31062, Toulouse, France.
- Institut Universitaire de France (IUF), Paris, France.
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20
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Oneto M, Scipioni L, Sarmento MJ, Cainero I, Pelicci S, Furia L, Pelicci PG, Dellino GI, Bianchini P, Faretta M, Gratton E, Diaspro A, Lanzanò L. Nanoscale Distribution of Nuclear Sites by Super-Resolved Image Cross-Correlation Spectroscopy. Biophys J 2019; 117:2054-2065. [PMID: 31732142 PMCID: PMC6895719 DOI: 10.1016/j.bpj.2019.10.036] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 10/21/2019] [Accepted: 10/29/2019] [Indexed: 02/07/2023] Open
Abstract
Deciphering the spatiotemporal coordination between nuclear functions is important to understand its role in the maintenance of human genome. In this context, super-resolution microscopy has gained considerable interest because it can be used to probe the spatial organization of functional sites in intact single-cell nuclei in the 20-250 nm range. Among the methods that quantify colocalization from multicolor images, image cross-correlation spectroscopy (ICCS) offers several advantages, namely it does not require a presegmentation of the image into objects and can be used to detect dynamic interactions. However, the combination of ICCS with super-resolution microscopy has not been explored yet. Here, we combine dual-color stimulated emission depletion (STED) nanoscopy with ICCS (STED-ICCS) to quantify the nanoscale distribution of functional nuclear sites. We show that super-resolved ICCS provides not only a value of the colocalized fraction but also the characteristic distances associated to correlated nuclear sites. As a validation, we quantify the nanoscale spatial distribution of three different pairs of functional nuclear sites in MCF10A cells. As expected, transcription foci and a transcriptionally repressive histone marker (H3K9me3) are not correlated. Conversely, nascent DNA replication foci and the proliferating cell nuclear antigen(PCNA) protein have a high level of proximity and are correlated at a nanometer distance scale that is close to the limit of our experimental approach. Finally, transcription foci are found at a distance of 130 nm from replication foci, indicating a spatial segregation at the nanoscale. Overall, our data demonstrate that STED-ICCS can be a powerful tool for the analysis of the nanoscale distribution of functional sites in the nucleus.
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Affiliation(s)
- Michele Oneto
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Lorenzo Scipioni
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, California
| | - Maria J Sarmento
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Isotta Cainero
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy
| | - Simone Pelicci
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy
| | - Laura Furia
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Pier G Pelicci
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Gaetano I Dellino
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy; Department of Oncology and Hemato-Oncology, University of Milan, Milan, Italy
| | - Paolo Bianchini
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Mario Faretta
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, Milan, Italy
| | - Enrico Gratton
- Laboratory for Fluorescence Dynamics, Department of Biomedical Engineering, University of California, Irvine, California
| | - Alberto Diaspro
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy; Department of Physics, University of Genoa, Genoa, Italy.
| | - Luca Lanzanò
- Nanoscopy and NIC@IIT, Istituto Italiano di Tecnologia, Genoa, Italy.
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21
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Liu W, Irudayaraj J. Understanding the dynamics and structure of epigenetic states with single-molecule fluorescence microscopy. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2019. [DOI: 10.1016/j.cobme.2019.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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22
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Polymer coil-globule phase transition is a universal folding principle of Drosophila epigenetic domains. Epigenetics Chromatin 2019; 12:28. [PMID: 31084607 PMCID: PMC6515630 DOI: 10.1186/s13072-019-0269-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 04/06/2019] [Indexed: 01/02/2023] Open
Abstract
Background Localized functional domains within chromosomes, known as topologically associating domains (TADs), have been recently highlighted. In Drosophila, TADs are biochemically defined by epigenetic marks, this suggesting that the 3D arrangement may be the “missing link” between epigenetics and gene activity. Recent observations (Boettiger et al. in Nature 529(7586):418–422, 2016) provide access to structural features of these domains with unprecedented resolution thanks to super-resolution experiments. In particular, they give access to the distribution of the radii of gyration for domains of different linear length and associated with different transcriptional activity states: active, inactive or repressed. Intriguingly, the observed scaling laws lack consistent interpretation in polymer physics. Results We develop a new methodology conceived to extract the best information from such super-resolution data by exploiting the whole distribution of gyration radii, and to place these experimental results on a theoretical framework. We show that the experimental data are compatible with the finite-size behavior of a self-attracting polymer. The same generic polymer model leads to quantitative differences between active, inactive and repressed domains. Active domains behave as pure polymer coils, while inactive and repressed domains both lie at the coil–globule crossover. For the first time, the “color-specificity” of both the persistence length and the mean interaction energy are estimated, leading to important differences between epigenetic states. Conclusion These results point toward a crucial role of criticality to enhance the system responsivity, resulting in both energy transitions and structural rearrangements. We get strong indications that epigenetically induced changes in nucleosome–nucleosome interaction can cause chromatin to shift between different activity states. Electronic supplementary material The online version of this article (10.1186/s13072-019-0269-6) contains supplementary material, which is available to authorized users.
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23
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Phasor histone FLIM-FRET microscopy quantifies spatiotemporal rearrangement of chromatin architecture during the DNA damage response. Proc Natl Acad Sci U S A 2019; 116:7323-7332. [PMID: 30918123 PMCID: PMC6462080 DOI: 10.1073/pnas.1814965116] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
To investigate how chromatin architecture is spatiotemporally organized at a double-strand break (DSB) repair locus, we established a biophysical method to quantify chromatin compaction at the nucleosome level during the DNA damage response (DDR). The method is based on phasor image-correlation spectroscopy of histone fluorescence lifetime imaging microscopy (FLIM)-Förster resonance energy transfer (FRET) microscopy data acquired in live cells coexpressing H2B-eGFP and H2B-mCherry. This multiplexed approach generates spatiotemporal maps of nuclear-wide chromatin compaction that, when coupled with laser microirradiation-induced DSBs, quantify the size, stability, and spacing between compact chromatin foci throughout the DDR. Using this technology, we identify that ataxia-telangiectasia mutated (ATM) and RNF8 regulate rapid chromatin decompaction at DSBs and formation of compact chromatin foci surrounding the repair locus. This chromatin architecture serves to demarcate the repair locus from the surrounding nuclear environment and modulate 53BP1 mobility.
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24
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Knoch TA. A Guided Protocol for Array Based T2C: A High-Quality Selective High-Resolution High-Throughput Chromosome Interaction Capture. ACTA ACUST UNITED AC 2018; 99:e55. [PMID: 30199150 DOI: 10.1002/cphg.55] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
After now more than 170 years of research the dynamic three-dimensional chromatin architecture of genomes and the co-evolved interaction networks of regulatory elements which create genome function - i.e. the storage, expression, and finally replication of genetic information - involves ever more investigative efforts in respect to not only the pure understanding of living organisms, but also diagnosis, treatment, and even future genome engineering. To study genomic interactions, we developed a novel and superior high-quality selective high-resolution, high-throughput chromosome interaction capture method - T2C (targeted chromatin capture) - which allows to arbitrarily balance resolution, frequency range of interactions, and the investigated general genetic region or single interactions in a highly cost-effective manner in respect to the obtainable result and compared to other techniques. Beyond, T2C has such a high signal-to-noise ratio at high resolution that the "genomic" statistical mechanics level can be reached. With the guided T2C protocol described here, we were already able to finally determine the chromatin quasi-fiber conformation and its folding into stable multi-loop aggregates/rosettes connected by a linker. Actually, this guided T2C protocol provides the means for architectural genome sequencing from the level of the single base pair to the entire cell nucleus and thus to analyze genetic interactions in respect to genome function in a systems biological manner in general as well as in settings ranging from basic research, via diagnostics and treatment, to genome engineering. © 2018 by John Wiley & Sons, Inc.
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Affiliation(s)
- Tobias A Knoch
- Biophysical Genomics, Department of Cell Biology & Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
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25
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Feng ZX, Li QZ, Meng JJ. Recognition of the long range enhancer-promoter interactions by further adding DNA structure properties and transcription factor binding motifs in human cell lines. J Theor Biol 2018; 445:136-150. [PMID: 29476833 DOI: 10.1016/j.jtbi.2018.02.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 02/07/2018] [Accepted: 02/20/2018] [Indexed: 11/17/2022]
Abstract
The enhancer-promoter interactions (EPIs) with strong tissue-specificity play an important role in cis-regulatory mechanism of human cell lines. However, it still remains a challenging work to predict these interactions so far. Due to that these interactions are regulated by the cooperativeness of diverse functional genomic signatures, DNA spatial structure and DNA sequence elements. In this paper, by adding DNA structure properties and transcription factor binding motifs, we presented an improved computational method to predict EPIs in human cell lines. In comparison with the results of other group on the same datasets, our best accuracies by cross-validation test were about 15%-24% higher in the same cell lines, and the accuracies by independent test were about 11%-15% higher in new cell lines. Meanwhile, we found that transcription factor binding motifs and DNA structure properties have important information that would largely determine long range EPIs prediction. From the distribution comparisons, we also found their distinct differences between interacting and non-interacting sets in each cell line. Then, the correlation analysis and network models for relationships among top-ranked functional genomic signatures indicated that diverse genomic signatures would cooperatively establish a complex regulatory network to facilitate long range EPIs. The experimental results provided additional insights about the roles of DNA intrinsic properties and functional genomic signatures in EPIs prediction.
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Affiliation(s)
- Zhen-Xing Feng
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China
| | - Qian-Zhong Li
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China; The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, Hohhot, 010070, China.
| | - Jian-Jun Meng
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China
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26
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Erdel F, Rippe K. Formation of Chromatin Subcompartments by Phase Separation. Biophys J 2018; 114:2262-2270. [PMID: 29628210 DOI: 10.1016/j.bpj.2018.03.011] [Citation(s) in RCA: 233] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 02/19/2018] [Accepted: 03/06/2018] [Indexed: 10/17/2022] Open
Abstract
Chromatin is partitioned on multiple length scales into subcompartments that differ from each other with respect to their molecular composition and biological function. It is a key question how these compartments can form even though diffusion constantly mixes the nuclear interior and rapidly balances concentration gradients of soluble nuclear components. Different biophysical concepts are currently used to explain the formation of "chromatin bodies" in a self-organizing manner and without consuming energy. They rationalize how soluble protein factors that are dissolved in the liquid nuclear phase, the nucleoplasm, bind and organize transcriptionally active or silenced chromatin domains. In addition to cooperative binding of proteins to a preformed chromatin structure, two different mechanisms for the formation of phase-separated chromatin subcompartments have been proposed. One is based on bridging proteins that cross-link polymer segments with particular properties. Bridging can induce a collapse of the nucleosome chain and associated factors into an ordered globular phase. The other mechanism is based on multivalent interactions among soluble molecules that bind to chromatin. These interactions can induce liquid-liquid phase separation, which drives the assembly of liquid-like nuclear bodies around the respective binding sites on chromatin. Both phase separation mechanisms can explain that chromatin bodies are dynamic spherical structures, which can coalesce and are in constant and rapid exchange with the surrounding nucleoplasm. However, they make distinct predictions about how the size, density, and stability of chromatin bodies depends on the concentration and interaction behavior of the molecules involved. Here, we compare the different biophysical mechanisms for the assembly of chromatin bodies and discuss experimental strategies to distinguish them from each other. Furthermore, we outline the implications for the establishment and memory of functional chromatin state patterns.
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Affiliation(s)
- Fabian Erdel
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany.
| | - Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany.
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27
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Developing novel methods to image and visualize 3D genomes. Cell Biol Toxicol 2018; 34:367-380. [PMID: 29577183 PMCID: PMC6133007 DOI: 10.1007/s10565-018-9427-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 03/11/2018] [Indexed: 02/07/2023]
Abstract
To investigate three-dimensional (3D) genome organization in prokaryotic and eukaryotic cells, three main strategies are employed, namely nuclear proximity ligation-based methods, imaging tools (such as fluorescence in situ hybridization (FISH) and its derivatives), and computational/visualization methods. Proximity ligation-based methods are based on digestion and re-ligation of physically proximal cross-linked chromatin fragments accompanied by massively parallel DNA sequencing to measure the relative spatial proximity between genomic loci. Imaging tools enable direct visualization and quantification of spatial distances between genomic loci, and advanced implementation of (super-resolution) microscopy helps to significantly improve the resolution of images. Computational methods are used to map global 3D genome structures at various scales driven by experimental data, and visualization methods are used to visualize genome 3D structures in virtual 3D space-based on algorithms. In this review, we focus on the introduction of novel imaging and visualization methods to study 3D genomes. First, we introduce the progress made recently in 3D genome imaging in both fixed cell and live cells based on long-probe labeling, short-probe labeling, RNA FISH, and the CRISPR system. As the fluorescence-capturing capability of a particular microscope is very important for the sensitivity of bioimaging experiments, we also introduce two novel super-resolution microscopy methods, SDOM and low-power super-resolution STED, which have potential for time-lapse super-resolution live-cell imaging of chromatin. Finally, we review some software tools developed recently to visualize proximity ligation-based data. The imaging and visualization methods are complementary to each other, and all three strategies are not mutually exclusive. These methods provide powerful tools to explore the mechanisms of gene regulation and transcription in cell nuclei.
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Scipioni L, Di Bona M, Vicidomini G, Diaspro A, Lanzanò L. Local raster image correlation spectroscopy generates high-resolution intracellular diffusion maps. Commun Biol 2018; 1:10. [PMID: 30271897 PMCID: PMC6053083 DOI: 10.1038/s42003-017-0010-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 12/15/2017] [Indexed: 01/01/2023] Open
Abstract
Raster image correlation spectroscopy (RICS) is a powerful method for measuring molecular diffusion in live cells directly from images acquired on a laser scanning microscope. However, RICS only provides single average diffusion coefficients from regions with a lateral size on the order of few micrometers, which means that its spatial resolution is mainly limited to the cellular level. Here we introduce the local RICS (L-RICS), an easy-to-use tool that generates high resolution maps of diffusion coefficients from images acquired on a laser scanning microscope. As an application we show diffusion maps of a green fluorescent protein (GFP) within the nucleus and within the nucleolus of live cells at an effective spatial resolution of 500 nm. We find not only that diffusion in the nucleolus is slowed down compared to diffusion in the nucleoplasm, but also that diffusion in the nucleolus is highly heterogeneous. Lorenzo Scipioni et al. present Local Raster Image Correlation Spectroscopy (L-RICS), a method for generating sub-micrometer diffusion maps. They apply L-RICS to GFP in live cells and find that diffusion coefficients differ between the nucleus and nucleolus and are highly heterogeneous within compartments.
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Affiliation(s)
- Lorenzo Scipioni
- Nanoscopy, Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.,Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genoa, Via All'Opera Pia, 13, 16145, Genoa, Italy
| | - Melody Di Bona
- Nanoscopy, Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.,Department of Physics, University of Genoa, via Dodecaneso 33, 16146, Genoa, Italy
| | - Giuseppe Vicidomini
- Molecular Microscopy and Spectroscopy, Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy
| | - Alberto Diaspro
- Nanoscopy, Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.,Department of Physics, University of Genoa, via Dodecaneso 33, 16146, Genoa, Italy.,Nikon Imaging Center, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy
| | - Luca Lanzanò
- Nanoscopy, Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, 16163, Genoa, Italy.
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Kolovos P, Brouwer RWW, Kockx CEM, Lesnussa M, Kepper N, Zuin J, Imam AMA, van de Werken HJG, Wendt KS, Knoch TA, van IJcken WFJ, Grosveld F. Investigation of the spatial structure and interactions of the genome at sub-kilobase-pair resolution using T2C. Nat Protoc 2018; 13:459-477. [DOI: 10.1038/nprot.2017.132] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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30
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Zinchenko A, Berezhnoy NV, Wang S, Rosencrans WM, Korolev N, van der Maarel JR, Nordenskiöld L. Single-molecule compaction of megabase-long chromatin molecules by multivalent cations. Nucleic Acids Res 2018; 46:635-649. [PMID: 29145649 PMCID: PMC5778610 DOI: 10.1093/nar/gkx1135] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 10/18/2017] [Accepted: 10/29/2017] [Indexed: 11/21/2022] Open
Abstract
To gain insight into the conformational properties and compaction of megabase-long chromatin molecules, we reconstituted chromatin from T4 phage DNA (165 kb) and recombinant human histone octamers (HO). The unimolecular compaction, induced by divalent Mg2+ or tetravalent spermine4+ cations, studied by single-molecule fluorescence microscopy (FM) and dynamic light scattering (DLS) techniques, resulted in the formation of 250-400 nm chromatin condensates. The compaction on this scale of DNA size is comparable to that of chromatin topologically associated domains (TAD) in vivo. Variation of HO loading revealed a number of unique features related to the efficiency of chromatin compaction by multivalent cations, the mechanism of compaction, and the character of partly compact chromatin structures. The observations may be relevant for how DNA accessibility in chromatin is maintained. Compaction of saturated chromatin, in turn, is accompanied by an intra-chain segregation at the level of single chromatin molecules, suggesting an intriguing scenario of selective activation/deactivation of DNA as a result of chromatin fiber heterogeneity due to the nucleosome positioning. We suggest that this chromatin, reconstituted on megabase-long DNA because of its large size, is a useful model of eukaryotic chromatin.
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Affiliation(s)
- Anatoly Zinchenko
- Graduate School of Environmental Studies, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
| | - Nikolay V Berezhnoy
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
| | - Sai Wang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
| | - William M Rosencrans
- Department of Physics and Astronomy, Colgate University, Hamilton, NY 13346, USA
| | - Nikolay Korolev
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
| | | | - Lars Nordenskiöld
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, 637551 Singapore
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31
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Jia R, Chai P, Zhang H, Fan X. Novel insights into chromosomal conformations in cancer. Mol Cancer 2017; 16:173. [PMID: 29149895 PMCID: PMC5693495 DOI: 10.1186/s12943-017-0741-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 11/06/2017] [Indexed: 12/20/2022] Open
Abstract
Exploring gene function is critical for understanding the complexity of life. DNA sequences and the three-dimensional organization of chromatin (chromosomal interactions) are considered enigmatic factors underlying gene function, and interactions between two distant fragments can regulate transactivation activity via mediator proteins. Thus, a series of chromosome conformation capture techniques have been developed, including chromosome conformation capture (3C), circular chromosome conformation capture (4C), chromosome conformation capture carbon copy (5C), and high-resolution chromosome conformation capture (Hi-C). The application of these techniques has expanded to various fields, but cancer remains one of the major topics. Interactions mediated by proteins or long noncoding RNAs (lncRNAs) are typically found using 4C-sequencing and chromatin interaction analysis by paired-end tag sequencing (ChIA-PET). Currently, Hi-C is used to identify chromatin loops between cancer risk-associated single-nucleotide polymorphisms (SNPs) found by genome-wide association studies (GWAS) and their target genes. Chromosomal conformations are responsible for altered gene regulation through several typical mechanisms and contribute to the biological behavior and malignancy of different tumors, particularly prostate cancer, breast cancer and hematologic neoplasms. Moreover, different subtypes may exhibit different 3D-chromosomal conformations. Thus, C-tech can be used to help diagnose cancer subtypes and alleviate cancer progression by destroying specific chromosomal conformations. Here, we review the fundamentals and improvements in chromosome conformation capture techniques and their clinical applications in cancer to provide insight for future research.
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Affiliation(s)
- Ruobing Jia
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, People's Republic of China
| | - Peiwei Chai
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, People's Republic of China
| | - He Zhang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China. .,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, People's Republic of China.
| | - Xianqun Fan
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China. .,Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology, Shanghai, People's Republic of China.
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32
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Feng ZX, Li QZ. Recognition of long-range enhancer-promoter interactions by adding genomic signatures of segmented regulatory regions. Genomics 2017; 109:341-352. [PMID: 28579514 DOI: 10.1016/j.ygeno.2017.05.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 05/16/2017] [Accepted: 05/31/2017] [Indexed: 01/21/2023]
Abstract
Enhancer-promoter interaction (EPI) is an important cis-regulatory mechanism in the regulation of tissue-specific gene expression. However, it still has limitation to precisely identity these interactions so far. In this paper, using diverse genomic features for various regulatory regions, we presented a computational approach to predict EPIs with improved accuracies. Meanwhile, we comprehensively studied more potential regulatory factors that are important to EPIs prediction, such as nucleosome occupancy, enhancer RNA; and found the cell line-specificity and region-specificity of the contributions of diverse regulatory signatures. By adding genomic signatures of segmented regulatory regions, our best accuracies of cross-validation test were about 11%-16% higher than the previous results, indicating the location-specificity of genomic signatures in a regulatory region for predicting EPIs. Additionally, more training samples and related features can provide reliable performances in new cell lines. Consequently, our study provided additional insights into the roles of diverse signature features for predicting long-range EPIs.
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Affiliation(s)
- Zhen-Xing Feng
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China
| | - Qian-Zhong Li
- Laboratory of Theoretical Biophysics, School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China.
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33
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Knoch TA, Wachsmuth M, Kepper N, Lesnussa M, Abuseiris A, Ali Imam AM, Kolovos P, Zuin J, Kockx CEM, Brouwer RWW, van de Werken HJG, van IJcken WFJ, Wendt KS, Grosveld FG. The detailed 3D multi-loop aggregate/rosette chromatin architecture and functional dynamic organization of the human and mouse genomes. Epigenetics Chromatin 2016; 9:58. [PMID: 28035242 PMCID: PMC5192698 DOI: 10.1186/s13072-016-0089-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 09/01/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The dynamic three-dimensional chromatin architecture of genomes and its co-evolutionary connection to its function-the storage, expression, and replication of genetic information-is still one of the central issues in biology. Here, we describe the much debated 3D architecture of the human and mouse genomes from the nucleosomal to the megabase pair level by a novel approach combining selective high-throughput high-resolution chromosomal interaction capture (T2C), polymer simulations, and scaling analysis of the 3D architecture and the DNA sequence. RESULTS The genome is compacted into a chromatin quasi-fibre with ~5 ± 1 nucleosomes/11 nm, folded into stable ~30-100 kbp loops forming stable loop aggregates/rosettes connected by similar sized linkers. Minor but significant variations in the architecture are seen between cell types and functional states. The architecture and the DNA sequence show very similar fine-structured multi-scaling behaviour confirming their co-evolution and the above. CONCLUSIONS This architecture, its dynamics, and accessibility, balance stability and flexibility ensuring genome integrity and variation enabling gene expression/regulation by self-organization of (in)active units already in proximity. Our results agree with the heuristics of the field and allow "architectural sequencing" at a genome mechanics level to understand the inseparable systems genomic properties.
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Affiliation(s)
- Tobias A. Knoch
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Malte Wachsmuth
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Nick Kepper
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
- Genome Organization and Function, BioQuant and German Cancer Research Center, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
| | - Michael Lesnussa
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Anis Abuseiris
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - A. M. Ali Imam
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
- Cell Biology, Department Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Petros Kolovos
- Biophysical Genomics, Department of Cell Biology and Genetics, Erasmus MC, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
- Cell Biology, Department Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Jessica Zuin
- Cohesin in Chromatin Structure and Gene Regulation, Department of Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Christel E. M. Kockx
- Center for Biomics, Department of Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Rutger W. W. Brouwer
- Center for Biomics, Department of Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Harmen J. G. van de Werken
- Cell Biology, Department Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Wilfred F. J. van IJcken
- Center for Biomics, Department of Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Kerstin S. Wendt
- Cohesin in Chromatin Structure and Gene Regulation, Department of Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
| | - Frank G. Grosveld
- Cell Biology, Department Cell Biology and Genetics, Erasmus MC, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands
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