1
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Mielczarek O, Rogers CH, Zhan Y, Matheson LS, Stubbington MJT, Schoenfelder S, Bolland DJ, Javierre BM, Wingett SW, Várnai C, Segonds-Pichon A, Conn SJ, Krueger F, Andrews S, Fraser P, Giorgetti L, Corcoran AE. Intra- and interchromosomal contact mapping reveals the Igh locus has extensive conformational heterogeneity and interacts with B-lineage genes. Cell Rep 2023; 42:113074. [PMID: 37676766 PMCID: PMC10548092 DOI: 10.1016/j.celrep.2023.113074] [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: 02/27/2023] [Revised: 06/28/2023] [Accepted: 08/18/2023] [Indexed: 09/09/2023] Open
Abstract
To produce a diverse antibody repertoire, immunoglobulin heavy-chain (Igh) loci undergo large-scale alterations in structure to facilitate juxtaposition and recombination of spatially separated variable (VH), diversity (DH), and joining (JH) genes. These chromosomal alterations are poorly understood. Uncovering their patterns shows how chromosome dynamics underpins antibody diversity. Using tiled Capture Hi-C, we produce a comprehensive map of chromatin interactions throughout the 2.8-Mb Igh locus in progenitor B cells. We find that the Igh locus folds into semi-rigid subdomains and undergoes flexible looping of the VH genes to its 3' end, reconciling two views of locus organization. Deconvolution of single Igh locus conformations using polymer simulations identifies thousands of different structures. This heterogeneity may underpin the diversity of V(D)J recombination events. All three immunoglobulin loci also participate in a highly specific, developmentally regulated network of interchromosomal interactions with genes encoding B cell-lineage factors. This suggests a model of interchromosomal coordination of B cell development.
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Affiliation(s)
- Olga Mielczarek
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Carolyn H Rogers
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Yinxiu Zhan
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Louise S Matheson
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Michael J T Stubbington
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Stefan Schoenfelder
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Daniel J Bolland
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Biola M Javierre
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Steven W Wingett
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Csilla Várnai
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Anne Segonds-Pichon
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon J Conn
- Flinders Health and Medical Research Institute, College of Medicine and Public Health, Flinders University, Bedford Park, SA 5042, Australia
| | - Felix Krueger
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon Andrews
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Peter Fraser
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Luca Giorgetti
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Anne E Corcoran
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Immunology Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
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2
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Jaros RK, Fadason T, Cameron-Smith D, Golovina E, O'Sullivan JM. Comorbidity genetic risk and pathways impact SARS-CoV-2 infection outcomes. Sci Rep 2023; 13:9879. [PMID: 37336921 DOI: 10.1038/s41598-023-36900-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 06/12/2023] [Indexed: 06/21/2023] Open
Abstract
Understanding the genetic risk and mechanisms through which SARS-CoV-2 infection outcomes and comorbidities interact to impact acute and long-term sequelae is essential if we are to reduce the ongoing health burdens of the COVID-19 pandemic. Here we use a de novo protein diffusion network analysis coupled with tissue-specific gene regulatory networks, to examine putative mechanisms for associations between SARS-CoV-2 infection outcomes and comorbidities. Our approach identifies a shared genetic aetiology and molecular mechanisms for known and previously unknown comorbidities of SARS-CoV-2 infection outcomes. Additionally, genomic variants, genes and biological pathways that provide putative causal mechanisms connecting inherited risk factors for SARS-CoV-2 infection and coronary artery disease and Parkinson's disease are identified for the first time. Our findings provide an in depth understanding of genetic impacts on traits that collectively alter an individual's predisposition to acute and post-acute SARS-CoV-2 infection outcomes. The existence of complex inter-relationships between the comorbidities we identify raises the possibility of a much greater post-acute burden arising from SARS-CoV-2 infection if this genetic predisposition is realised.
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Affiliation(s)
- Rachel K Jaros
- The Liggins Institute, The University of Auckland, Auckland, 1023, New Zealand
| | - Tayaza Fadason
- The Liggins Institute, The University of Auckland, Auckland, 1023, New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, 1010, New Zealand
| | - David Cameron-Smith
- College of Health, Medicine and Wellbeing, The University of Newcastle, Callaghan, 2308, Australia
| | - Evgeniia Golovina
- The Liggins Institute, The University of Auckland, Auckland, 1023, New Zealand
| | - Justin M O'Sullivan
- The Liggins Institute, The University of Auckland, Auckland, 1023, New Zealand.
- Maurice Wilkins Centre for Molecular Biodiscovery, The University of Auckland, Auckland, 1010, New Zealand.
- MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK.
- Singapore Institute for Clinical Sciences, Agency for Science, Technology and Research (A*STAR), Singapore, Singapore.
- Australian Parkinson's Mission, Garvan Institute of Medical Research, Sydney, NSW, Australia.
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3
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Cuartero S, Stik G, Stadhouders R. Three-dimensional genome organization in immune cell fate and function. Nat Rev Immunol 2022; 23:206-221. [PMID: 36127477 DOI: 10.1038/s41577-022-00774-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2022] [Indexed: 11/09/2022]
Abstract
Immune cell development and activation demand the precise and coordinated control of transcriptional programmes. Three-dimensional (3D) organization of the genome has emerged as an important regulator of chromatin state, transcriptional activity and cell identity by facilitating or impeding long-range genomic interactions among regulatory elements and genes. Chromatin folding thus enables cell type-specific and stimulus-specific transcriptional responses to extracellular signals, which are essential for the control of immune cell fate, for inflammatory responses and for generating a diverse repertoire of antigen receptor specificities. Here, we review recent findings connecting 3D genome organization to the control of immune cell differentiation and function, and discuss how alterations in genome folding may lead to immune dysfunction and malignancy.
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Affiliation(s)
- Sergi Cuartero
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, Spain. .,Germans Trias i Pujol Research Institute (IGTP), Badalona, Spain.
| | - Grégoire Stik
- Centre for Genomic Regulation (CRG), Institute of Science and Technology (BIST), Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain.
| | - Ralph Stadhouders
- Department of Pulmonary Medicine, Erasmus MC, University Medical Center, Rotterdam, The Netherlands. .,Department of Cell Biology, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
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4
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Gilbertson SE, Walter HC, Gardner K, Wren SN, Vahedi G, Weinmann AS. Topologically associating domains are disrupted by evolutionary genome rearrangements forming species-specific enhancer connections in mice and humans. Cell Rep 2022; 39:110769. [PMID: 35508135 PMCID: PMC9142060 DOI: 10.1016/j.celrep.2022.110769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 03/08/2022] [Accepted: 04/11/2022] [Indexed: 12/11/2022] Open
Abstract
Distinguishing between conserved and divergent regulatory mechanisms is
essential for translating preclinical research from mice to humans, yet there is
a lack of information about how evolutionary genome rearrangements affect the
regulation of the immune response, a rapidly evolving system. The current model
is topologically associating domains (TADs) are conserved between species,
buffering evolutionary rearrangements and conserving long-range interactions
within a TAD. However, we find that TADs frequently span evolutionary
translocation and inversion breakpoints near genes with species-specific
expression in immune cells, creating unique enhancer-promoter interactions
exclusive to the mouse or human genomes. This includes TADs encompassing
immune-related transcription factors, cytokines, and receptors. For example, we
uncover an evolutionary rearrangement that created a shared LPS-inducible
regulatory module between OASL and P2RX7 in
human macrophages that is absent in mice. Therefore, evolutionary genome
rearrangements disrupt TAD boundaries, enabling sequence-conserved enhancer
elements from divergent genomic locations between species to create unique
regulatory modules. It is currently unclear how evolutionary genome rearrangements affecting
the mouse and human genomes influence the expression of genes important in
immunity. Gilbertson et al. report that evolutionary genome rearrangements
disrupt topologically associating domain boundaries, enabling sequence-conserved
enhancer elements from divergent locations between species to create unique
regulatory modules.
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Affiliation(s)
- Sarah E Gilbertson
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Hannah C Walter
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Katherine Gardner
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Spencer N Wren
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Golnaz Vahedi
- Department of Genetics, Institute of Immunology, Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Amy S Weinmann
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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5
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Landa B, Zhang TTCK, Kluger Y. Biwhitening Reveals the Rank of a Count Matrix. SIAM JOURNAL ON MATHEMATICS OF DATA SCIENCE 2022; 4:1420-1446. [PMID: 37576699 PMCID: PMC10417917 DOI: 10.1137/21m1456807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Estimating the rank of a corrupted data matrix is an important task in data analysis, most notably for choosing the number of components in PCA. Significant progress on this task was achieved using random matrix theory by characterizing the spectral properties of large noise matrices. However, utilizing such tools is not straightforward when the data matrix consists of count random variables, e.g., Poisson, in which case the noise can be heteroskedastic with an unknown variance in each entry. In this work, we focus on a Poisson random matrix with independent entries and propose a simple procedure, termed biwhitening, for estimating the rank of the underlying signal matrix (i.e., the Poisson parameter matrix) without any prior knowledge. Our approach is based on the key observation that one can scale the rows and columns of the data matrix simultaneously so that the spectrum of the corresponding noise agrees with the standard Marchenko-Pastur (MP) law, justifying the use of the MP upper edge as a threshold for rank selection. Importantly, the required scaling factors can be estimated directly from the observations by solving a matrix scaling problem via the Sinkhorn-Knopp algorithm. Aside from the Poisson, our approach is extended to families of distributions that satisfy a quadratic relation between the mean and the variance, such as the generalized Poisson, binomial, negative binomial, gamma, and many others. This quadratic relation can also account for missing entries in the data. We conduct numerical experiments that corroborate our theoretical findings, and showcase the advantage of our approach for rank estimation in challenging regimes. Furthermore, we demonstrate the favorable performance of our approach on several real datasets of single-cell RNA sequencing (scRNA-seq), High-Throughput Chromosome Conformation Capture (Hi-C), and document topic modeling.
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Affiliation(s)
- Boris Landa
- Program in Applied Mathematics, Yale University
| | - Thomas T C K Zhang
- Department of Electrical and Systems Engineering, University of Pennsylvania
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6
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Chan WF, Coughlan HD, Zhou JHS, Keenan CR, Bediaga NG, Hodgkin PD, Smyth GK, Johanson TM, Allan RS. Pre-mitotic genome re-organisation bookends the B cell differentiation process. Nat Commun 2021; 12:1344. [PMID: 33637722 PMCID: PMC7910489 DOI: 10.1038/s41467-021-21536-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 02/02/2021] [Indexed: 01/08/2023] Open
Abstract
During cellular differentiation chromosome conformation is intricately remodelled to support the lineage-specific transcriptional programs required for initiating and maintaining lineage identity. When these changes occur in relation to cell cycle, division and time in response to cellular activation and differentiation signals has yet to be explored, although it has been proposed to occur during DNA synthesis or after mitosis. Here, we elucidate the chromosome conformational changes in B lymphocytes as they differentiate and expand from a naive, quiescent state into antibody secreting plasma cells. We find gene-regulatory chromosome reorganization in late G1 phase before the first division, and that this configuration is remarkably stable as the cells massively and rapidly clonally expand. A second wave of conformational change occurs as cells terminally differentiate into plasma cells, coincident with increased time in G1 phase. These results provide further explanation for how lymphocyte fate is imprinted prior to the first division. They also suggest that chromosome reconfiguration occurs prior to DNA replication and mitosis, and is linked to a gene expression program that controls the differentiation process required for the generation of immunity.
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Affiliation(s)
- Wing Fuk Chan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Hannah D Coughlan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Jie H S Zhou
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Christine R Keenan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Naiara G Bediaga
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Philip D Hodgkin
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Gordon K Smyth
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,School of Mathematics and Statistics, The University of Melbourne, Parkville, VIC, Australia
| | - Timothy M Johanson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Rhys S Allan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia. .,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia.
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7
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Keenan CR, Mlodzianoski MJ, Coughlan HD, Bediaga NG, Naselli G, Lucas EC, Wang Q, de Graaf CA, Hilton DJ, Harrison LC, Smyth GK, Rogers KL, Boudier T, Allan RS, Johanson TM. Chromosomes distribute randomly to, but not within, human neutrophil nuclear lobes. iScience 2021; 24:102161. [PMID: 33665577 PMCID: PMC7905186 DOI: 10.1016/j.isci.2021.102161] [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: 10/12/2020] [Revised: 11/24/2020] [Accepted: 02/03/2021] [Indexed: 11/19/2022] Open
Abstract
The proximity pattern and radial distribution of chromosome territories within spherical nuclei are random and non-random, respectively. Whether this distribution pattern is conserved in the partitioned or lobed nuclei of polymorphonuclear cells is unclear. Here we use chromosome paint technology to examine the chromosome territories of all 46 chromosomes in hundreds of single human neutrophils - an abundant and famously polymorphonuclear immune cell. By comparing the distribution of chromosomes to randomly shuffled controls and validating with orthogonal chromosome conformation capture technology, we show for the first time that human chromosomes randomly distribute to neutrophil nuclear lobes, while maintaining a non-random radial distribution within these lobes. Furthermore, we demonstrate that chromosome length correlates with three-dimensional volume not only in neutrophils but other human immune cells. This work demonstrates that chromosomes are largely passive passengers during the neutrophil lobing process but are able to subsequently maintain their macro-level organization within lobes.
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Affiliation(s)
- Christine R. Keenan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Michael J. Mlodzianoski
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hannah D. Coughlan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Naiara G. Bediaga
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Gaetano Naselli
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Erin C. Lucas
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Qike Wang
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Carolyn A. de Graaf
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Douglas J. Hilton
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Leonard C. Harrison
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Gordon K. Smyth
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- School of Mathematics and Statistics, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Kelly L. Rogers
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Thomas Boudier
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
- Institute of Biology Paris-Seine, Sorbonne Université, Paris, France
| | - Rhys S. Allan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Timothy M. Johanson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville, VIC, 3010, Australia
- Corresponding author
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8
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Multi-level remodelling of chromatin underlying activation of human T cells. Sci Rep 2021; 11:528. [PMID: 33436846 PMCID: PMC7804404 DOI: 10.1038/s41598-020-80165-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 12/15/2020] [Indexed: 02/06/2023] Open
Abstract
Remodelling of chromatin architecture is known to regulate gene expression and has been well characterized in cell lineage development but less so in response to cell perturbation. Activation of T cells, which triggers extensive changes in transcriptional programs, serves as an instructive model to elucidate how changes in chromatin architecture orchestrate gene expression in response to cell perturbation. To characterize coordinate changes at different levels of chromatin architecture, we analyzed chromatin accessibility, chromosome conformation and gene expression in activated human T cells. T cell activation was characterized by widespread changes in chromatin accessibility and interactions that were shared between activated CD4+ and CD8+ T cells, and with the formation of active regulatory regions associated with transcription factors relevant to T cell biology. Chromatin interactions that increased and decreased were coupled, respectively, with up- and down-regulation of corresponding target genes. Furthermore, activation was associated with disruption of long-range chromatin interactions and with partitioning of topologically associating domains (TADs) and remodelling of their TAD boundaries. Newly formed/strengthened TAD boundaries were associated with higher nucleosome occupancy and lower accessibility, linking changes in lower and higher order chromatin architecture. T cell activation exemplifies coordinate multi-level remodelling of chromatin underlying gene transcription.
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9
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Chan WF, Coughlan HD, Iannarella N, Smyth GK, Johanson TM, Keenan CR, Allan RS. Identification and characterization of the long noncoding RNA Dreg1 as a novel regulator of Gata3. Immunol Cell Biol 2020; 99:323-332. [PMID: 32970351 DOI: 10.1111/imcb.12408] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/22/2020] [Indexed: 01/05/2023]
Abstract
The eukaryotic genome is three-dimensionally segregated into discrete globules of topologically associating domains (TADs), within which numerous cis-regulatory elements such as enhancers and promoters interact to regulate gene expression. In this study, we identify a T-cell-specific sub-TAD containing the Gata3 locus, and reveal a previously uncharacterized long noncoding RNA (Dreg1) within a distant enhancer lying approximately 280 kb downstream of Gata3. Dreg1 expression is highly correlated with that of Gata3 during early immune system development and T helper type 2 cell differentiation. Inhibition and overexpression of Dreg1 suggest that it may be involved in the establishment, but not in the maintenance of Gata3 expression. Overall, we propose that Dreg1 is a novel regulator of Gata3 and may inform therapeutic strategies in diseases such allergy and lymphoma, where Gata3 has a pathological role.
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Affiliation(s)
- Wing Fuk Chan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Hannah D Coughlan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Nadia Iannarella
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - Gordon K Smyth
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,School of Mathematics and Statistics, The University of Melbourne, Parkville, VIC, Australia
| | - Timothy M Johanson
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Christine R Keenan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Rhys S Allan
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
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10
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Abstract
Tumor immunology is undergoing a renaissance due to the recent profound clinical successes of tumor immunotherapy. These advances have coincided with an exponential growth in the development of -omics technologies. Armed with these technologies and their associated computational and modeling toolsets, systems biologists have turned their attention to tumor immunology in an effort to understand the precise nature and consequences of interactions between tumors and the immune system. Such interactions are inherently multivariate, spanning multiple time and size scales, cell types, and organ systems, rendering systems biology approaches particularly amenable to their interrogation. While in its infancy, the field of 'Cancer Systems Immunology' has already influenced our understanding of tumor immunology and immunotherapy. As the field matures, studies will move beyond descriptive characterizations toward functional investigations of the emergent behavior that govern tumor-immune responses. Thus, Cancer Systems Immunology holds incredible promise to advance our ability to fight this disease.
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Affiliation(s)
| | - Edgar G Engleman
- Department of Pathology, Stanford University School of MedicineStanfordUnited States
- Division of Immunology and Rheumatology, Department of Medicine, Stanford University School of MedicineStanfordUnited States
- Stanford Cancer Institute, Stanford UniversityStanfordUnited States
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11
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Bashkirova E, Lomvardas S. Olfactory receptor genes make the case for inter-chromosomal interactions. Curr Opin Genet Dev 2019; 55:106-113. [PMID: 31491591 DOI: 10.1016/j.gde.2019.07.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 12/11/2022]
Abstract
The partitioning of the interphase nucleus into chromosome territories generally precludes DNA from making specific and reproducible inter-chromosomal contacts. However, with the development of powerful genomic and imaging tools for the analysis of the 3D genome, and with their application on an increasing number of cell types, it becomes apparent that regulated, specific, and functionally important inter-chromosomal contacts exist. Widespread and stereotypic inter-chromosomal interactions are at the center of chemosensation, where they regulate the singular and stochastic expression of olfactory receptor genes. In olfactory sensory neurons (OSNs) coalescence of multiple intergenic enhancers to a multi-chromosomal hub orchestrates the expression of a single OR allele, whereas convergence of the remaining OR genes from 18 chromosomes into a few heterochromatic compartments mediates their effective transcriptional silencing. In this review we describe the role of interchromosomal interactions in OR gene choice, and we describe other biological systems where such genomic interactions may contribute to regulatory robustness and transcriptional diversification.
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Affiliation(s)
- Elizaveta Bashkirova
- Department of Biochemistry and Molecular Biophysics, Roy Vangelos Columbia University Medical Center, New York, NY 10032, United States
| | - Stavros Lomvardas
- Department of Biochemistry and Molecular Biophysics, Roy Vangelos Columbia University Medical Center, New York, NY 10032, United States; Department of Neuroscience, Roy Vangelos Columbia University Medical Center, Columbia University, New York, NY 10032, United States; Zuckerman Mind Brain and Behavior Institute, Columbia University, New York, NY 10027, United States; Kavli Institute for Neurosciences at Columbia University, New York, NY 10027, United States.
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12
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13
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Eijsbouts CQ, Burren OS, Newcombe PJ, Wallace C. Fine mapping chromatin contacts in capture Hi-C data. BMC Genomics 2019; 20:77. [PMID: 30674271 PMCID: PMC6343296 DOI: 10.1186/s12864-018-5314-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 11/27/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Hi-C and capture Hi-C (CHi-C) are used to map physical contacts between chromatin regions in cell nuclei using high-throughput sequencing. Analysis typically proceeds considering the evidence for contacts between each possible pair of fragments independent from other pairs. This can produce long runs of fragments which appear to all make contact with the same baited fragment of interest. RESULTS We hypothesised that these long runs could result from a smaller subset of direct contacts and propose a new method, based on a Bayesian sparse variable selection approach, which attempts to fine map these direct contacts. Our model is conceptually novel, exploiting the spatial pattern of counts in CHi-C data. Although we use only the CHi-C count data in fitting the model, we show that the fragments prioritised display biological properties that would be expected of true contacts: for bait fragments corresponding to gene promoters, we identify contact fragments with active chromatin and contacts that correspond to edges found in previously defined enhancer-target networks; conversely, for intergenic bait fragments, we identify contact fragments corresponding to promoters for genes expressed in that cell type. We show that long runs of apparently co-contacting fragments can typically be explained using a subset of direct contacts consisting of <10% of the number in the full run, suggesting that greater resolution can be extracted from existing datasets. CONCLUSIONS Our results appear largely complementary to those from a per-fragment analytical approach, suggesting that they provide an additional level of interpretation that may be used to increase resolution for mapping direct contacts in CHi-C experiments.
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Affiliation(s)
- Christiaan Q Eijsbouts
- Department of Medicine, University of Cambridge, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
- MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge, UK
- Current address: Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, UK
| | - Oliver S Burren
- Department of Medicine, University of Cambridge, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
| | - Paul J Newcombe
- MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge, UK
| | - Chris Wallace
- Department of Medicine, University of Cambridge, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
- MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge, UK
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14
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LHX2- and LDB1-mediated trans interactions regulate olfactory receptor choice. Nature 2019; 565:448-453. [PMID: 30626972 PMCID: PMC6436840 DOI: 10.1038/s41586-018-0845-0] [Citation(s) in RCA: 190] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 12/06/2018] [Indexed: 01/28/2023]
Abstract
The genome is partitioned into topologically associated domains (TADs) and genomic compartments of shared chromatin valance. This architecture is constrained by the DNA polymer, which precludes genic interactions between chromosomes. Here, we report a dramatic divergence from this pattern of nuclear organization that occurs in mouse olfactory sensory neurons (OSNs). In situ HiC on FAC-sorted OSNs and their progenitors shows that olfactory receptor (OR) gene clusters from 18 chromosomes make specific and robust interchromosomal contacts that increase with differentiation. These contacts are orchestrated by intergenic OR enhancers, the Greek Islands, which first contribute to the formation of OR compartments and then form a multi-chromosomal super-enhancer that associates with the single active OR. Greek Island-bound transcription factor Lhx2 and adaptor protein Ldb1 regulate the assembly and maintenance of OR compartments, Greek Island hubs, and OR transcription, providing mechanistic insight and functional support for the role of trans interactions in gene expression.
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15
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Szalaj P, Plewczynski D. Three-dimensional organization and dynamics of the genome. Cell Biol Toxicol 2018; 34:381-404. [PMID: 29568981 PMCID: PMC6133016 DOI: 10.1007/s10565-018-9428-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 03/11/2018] [Indexed: 12/30/2022]
Abstract
Genome is a complex hierarchical structure, and its spatial organization plays an important role in its function. Chromatin loops and topological domains form the basic structural units of this multiscale organization and are essential to orchestrate complex regulatory networks and transcription mechanisms. They also form higher-order structures such as chromosomal compartments and chromosome territories. Each level of this intrinsic architecture is governed by principles and mechanisms that we only start to understand. In this review, we summarize the current view of the genome architecture on the scales ranging from chromatin loops to the whole genome. We describe cell-to-cell variability, links between genome reorganization and various genomic processes, such as chromosome X inactivation and cell differentiation, and the interplay between different experimental techniques.
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Affiliation(s)
- Przemyslaw Szalaj
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland.
- I-BioStat, Hasselt University, Hasselt, Belgium.
- Centre of New Technologies, University of Warsaw, Warsaw, Poland.
| | - Dariusz Plewczynski
- Centre for Innovative Research, Medical University of Bialystok, Białystok, Poland
- Centre of New Technologies, University of Warsaw, Warsaw, Poland
- Faculty of Mathematics and Information Science, Warsaw University of Technology, Warsaw, Poland
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