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Aboreden NG, Lam JC, Goel VY, Wang S, Wang X, Midla SC, Quijano A, Keller CA, Giardine BM, Hardison RC, Zhang H, Hansen AS, Blobel GA. LDB1 establishes multi-enhancer networks to regulate gene expression. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.08.23.609430. [PMID: 39229045 PMCID: PMC11370584 DOI: 10.1101/2024.08.23.609430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
How specific enhancer-promoter pairing is established is still mostly unclear. Besides the CTCF/cohesin machinery, only a few nuclear factors have been studied for a direct role in physically connecting regulatory elements. Here, we show via acute degradation experiments that LDB1 directly and broadly promotes enhancer-promoter loops. Most LDB1-mediated contacts, even those spanning hundreds of kb, can form in the absence of CTCF, cohesin, or YY1 as determined via the use of multiple degron systems. Moreover, an engineered LDB1-driven chromatin loop is cohesin independent. Cohesin-driven loop extrusion does not stall at LDB1 occupied sites but may aid the formation of a subset of LDB1 anchored loops. Leveraging the dynamic reorganization of nuclear architecture during the transition from mitosis to G1-phase, we establish a relationship between LDB1-dependent interactions in the context of TAD organization and gene activation. Lastly, Tri-C and Region Capture Micro-C reveal that LDB1 organizes multi-enhancer networks to activate transcription. This establishes LDB1 as a direct driver of regulatory network inter-connectivity.
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Affiliation(s)
- Nicholas G Aboreden
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Jessica C Lam
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Viraat Y Goel
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
| | - Siqing Wang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Xiaokang Wang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Susannah C Midla
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Alma Quijano
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Cheryl A Keller
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Belinda M Giardine
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Ross C Hardison
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA, USA
| | - Haoyue Zhang
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, Guangdong, China
| | - Anders S Hansen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Gene Regulation Observatory, Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Koch Institute for Integrative Cancer Research, Cambridge, MA, USA
| | - Gerd A Blobel
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
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2
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Guckelberger P, Doughty BR, Munson G, Rao SSP, Tan Y, Cai XS, Fulco CP, Nasser J, Mualim KS, Bergman DT, Ray J, Jagoda E, Munger CJ, Gschwind AR, Sheth MU, Tan AS, Pulido SG, Mitra N, Weisz D, Shamim MS, Durand NC, Mahajan R, Khan R, Steinmetz LM, Kanemaki MT, Lander ES, Meissner A, Aiden EL, Engreitz JM. Cohesin-mediated 3D contacts tune enhancer-promoter regulation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.12.603288. [PMID: 39026740 PMCID: PMC11257546 DOI: 10.1101/2024.07.12.603288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Enhancers are key drivers of gene regulation thought to act via 3D physical interactions with the promoters of their target genes. However, genome-wide depletions of architectural proteins such as cohesin result in only limited changes in gene expression, despite a loss of contact domains and loops. Consequently, the role of cohesin and 3D contacts in enhancer function remains debated. Here, we developed CRISPRi of regulatory elements upon degron operation (CRUDO), a novel approach to measure how changes in contact frequency impact enhancer effects on target genes by perturbing enhancers with CRISPRi and measuring gene expression in the presence or absence of cohesin. We systematically perturbed all 1,039 candidate enhancers near five cohesin-dependent genes and identified 34 enhancer-gene regulatory interactions. Of 26 regulatory interactions with sufficient statistical power to evaluate cohesin dependence, 18 show cohesin-dependent effects. A decrease in enhancer-promoter contact frequency upon removal of cohesin is frequently accompanied by a decrease in the regulatory effect of the enhancer on gene expression, consistent with a contact-based model for enhancer function. However, changes in contact frequency and regulatory effects on gene expression vary as a function of distance, with distal enhancers (e.g., >50Kb) experiencing much larger changes than proximal ones (e.g., <50Kb). Because most enhancers are located close to their target genes, these observations can explain how only a small subset of genes - those with strong distal enhancers - are sensitive to cohesin. Together, our results illuminate how 3D contacts, influenced by both cohesin and genomic distance, tune enhancer effects on gene expression.
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Martitz A, Schulz EG. Spatial orchestration of the genome: topological reorganisation during X-chromosome inactivation. Curr Opin Genet Dev 2024; 86:102198. [PMID: 38663040 DOI: 10.1016/j.gde.2024.102198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/21/2024] [Accepted: 04/05/2024] [Indexed: 06/11/2024]
Abstract
Genomes are organised through hierarchical structures, ranging from local kilobase-scale cis-regulatory contacts to large chromosome territories. Most notably, (sub)-compartments partition chromosomes according to transcriptional activity, while topologically associating domains (TADs) define cis-regulatory landscapes. The inactive X chromosome in mammals has provided unique insights into the regulation and function of the three-dimensional (3D) genome. Concurrent with silencing of the majority of genes and major alterations of its chromatin state, the X chromosome undergoes profound spatial rearrangements at multiple scales. These include the emergence of megadomains, alterations of the compartment structure and loss of the majority of TADs. Moreover, the Xist locus, which orchestrates X-chromosome inactivation, has provided key insights into regulation and function of regulatory domains. This review provides an overview of recent insights into the control of these structural rearrangements and contextualises them within a broader understanding of 3D genome organisation.
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Affiliation(s)
- Alexandra Martitz
- Systems Epigenetics, Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany; Department of Biology, Chemistry, Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Edda G Schulz
- Systems Epigenetics, Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.
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4
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Matiz-Ceron L, Okuno M, Itoh T, Yoshida I, Mizushima S, Toyoda A, Jogahara T, Kuroiwa A. Loss of One X and the Y Chromosome Changes the Configuration of the X Inactivation Center in the Genus Tokudaia. Cytogenet Genome Res 2024; 164:23-32. [PMID: 38754392 DOI: 10.1159/000539294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 05/08/2024] [Indexed: 05/18/2024] Open
Abstract
INTRODUCTION X chromosome inactivation (XCI) is an essential mechanism for dosage compensation between females and males in mammals. In females, XCI is controlled by a complex, conserved locus termed the X inactivation center (Xic), in which the lncRNA Xist is the key regulator. However, little is known about the Xic in species with unusual sex chromosomes. The genus Tokudaia includes three rodent species endemic to Japan. Tokudaia osimensis and Tokudaia tokunoshimensis lost the Y chromosome (XO/XO), while Tokudaia muenninki (TMU) acquired a neo-X region by fusion of the X chromosome and an autosome (XX/XY). We compared the gene location and structure in the Xic among Tokudaia species. METHODS Gene structure of nine genes in Xic was predicted, and the gene location and genome sequences of Xic were compared between mouse and Tokudaia species. The expression level of the gene was confirmed by transcripts per million calculation using RNA-seq data. RESULTS Compared to mouse, the Xic gene order and location were conserved in Tokudaia species. However, remarkable structure changes were observed in lncRNA genes, Xist and Tsix, in the XO/XO species. In Xist, important functional repeats, B-, C-, D-, and E-repeats, were partially or completely lost due to deletions in these species. RNA-seq data showed that female-specific expression patterns of Xist and Tsix were confirmed in TMU, however, not in the XO/XO species. Additionally, three deletions and one inversion were confirmed in the intergenic region between Jpx and Ftx in the XO/XO species. CONCLUSION Our findings indicate that even if the Xist and Tsix lncRNAs are expressed, they are incapable of producing a successful and lasting XCI in the XO/XO species. We hypothesized that the significant structure change in the intergenic region of Jpx-Ftx resulted in the inability to perform the XCI, and, as a result, a lack of Xist expression. Our results collectively suggest that structural changes in the Xic occurred in the ancestral lineage of XO/XO species, likely due to the loss of one X chromosome and the Y chromosome as a consequence of the degradation of the XCI system.
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Affiliation(s)
- Luisa Matiz-Ceron
- Reproductive and Developmental Science, Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Miki Okuno
- Division of Microbiology, Department of Infectious Medicine, Kurume University School of Medicine, Kurume, Fukuoka, Japan
| | - Takehiko Itoh
- School of Life Science and Technology, Tokyo Institute of Technology, Tokyo, Japan
| | - Ikuya Yoshida
- Reproductive and Developmental Science, Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
- Division of Reproductive and Developmental Biology, Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Shusei Mizushima
- Reproductive and Developmental Science, Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
- Division of Reproductive and Developmental Biology, Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Shizuoka, Japan
- Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka, Japan
| | - Takamichi Jogahara
- Faculty of Law, Economics and Management, Okinawa University, Naha, Okinawa, Japan
| | - Asato Kuroiwa
- Reproductive and Developmental Science, Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
- Division of Reproductive and Developmental Biology, Department of Biological Sciences, Faculty of Science, Hokkaido University, Sapporo, Japan
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5
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Ferrer J, Dimitrova N. Transcription regulation by long non-coding RNAs: mechanisms and disease relevance. Nat Rev Mol Cell Biol 2024; 25:396-415. [PMID: 38242953 PMCID: PMC11045326 DOI: 10.1038/s41580-023-00694-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2023] [Indexed: 01/21/2024]
Abstract
Long non-coding RNAs (lncRNAs) outnumber protein-coding transcripts, but their functions remain largely unknown. In this Review, we discuss the emerging roles of lncRNAs in the control of gene transcription. Some of the best characterized lncRNAs have essential transcription cis-regulatory functions that cannot be easily accomplished by DNA-interacting transcription factors, such as XIST, which controls X-chromosome inactivation, or imprinted lncRNAs that direct allele-specific repression. A growing number of lncRNA transcription units, including CHASERR, PVT1 and HASTER (also known as HNF1A-AS1) act as transcription-stabilizing elements that fine-tune the activity of dosage-sensitive genes that encode transcription factors. Genetic experiments have shown that defects in such transcription stabilizers often cause severe phenotypes. Other lncRNAs, such as lincRNA-p21 (also known as Trp53cor1) and Maenli (Gm29348) contribute to local activation of gene transcription, whereas distinct lncRNAs influence gene transcription in trans. We discuss findings of lncRNAs that elicit a function through either activation of their transcription, transcript elongation and processing or the lncRNA molecule itself. We also discuss emerging evidence of lncRNA involvement in human diseases, and their potential as therapeutic targets.
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Affiliation(s)
- Jorge Ferrer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain.
- Department of Metabolism, Digestion and Reproduction, Imperial College London, London, UK.
| | - Nadya Dimitrova
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
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6
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van Heyningen V. Stochasticity in genetics and gene regulation. Philos Trans R Soc Lond B Biol Sci 2024; 379:20230476. [PMID: 38432316 PMCID: PMC10909507 DOI: 10.1098/rstb.2023.0476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 12/20/2023] [Indexed: 03/05/2024] Open
Abstract
Development from fertilized egg to functioning multi-cellular organism requires precision. There is no precision, and often no survival, without plasticity. Plasticity is conferred partly by stochastic variation, present inherently in all biological systems. Gene expression levels fluctuate ubiquitously through transcription, alternative splicing, translation and turnover. Small differences in gene expression are exploited to trigger early differentiation, conferring distinct function on selected individual cells and setting in motion regulatory interactions. Non-selected cells then acquire new functions along the spatio-temporal developmental trajectory. The differentiation process has many stochastic components. Meiotic segregation, mitochondrial partitioning, X-inactivation and the dynamic DNA binding of transcription factor assemblies-all exhibit randomness. Non-random X-inactivation generally signals deleterious X-linked mutations. Correct neural wiring, such as retina to brain, arises through repeated confirmatory activity of connections made randomly. In immune system development, both B-cell antibody generation and the emergence of balanced T-cell categories begin through stochastic trial and error followed by functional selection. Aberrant selection processes lead to immune dysfunction. DNA sequence variants also arise through stochastic events: some involving environmental fluctuation (radiation or presence of pollutants), or genetic repair system malfunction. The phenotypic outcome of mutations is also fluid. Mutations may be advantageous in some circumstances, deleterious in others. This article is part of a discussion meeting issue 'Causes and consequences of stochastic processes in development and disease'.
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Affiliation(s)
- Veronica van Heyningen
- UCL Institute of Ophthalmology, University College London, London, EC1V 9EL, UK
- MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh EH4 2XU, UK
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7
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Luchsinger-Morcelle SJ, Gribnau J, Mira-Bontenbal H. Orchestrating Asymmetric Expression: Mechanisms behind Xist Regulation. EPIGENOMES 2024; 8:6. [PMID: 38390897 PMCID: PMC10885031 DOI: 10.3390/epigenomes8010006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/19/2024] [Accepted: 01/22/2024] [Indexed: 02/24/2024] Open
Abstract
Compensation for the gene dosage disequilibrium between sex chromosomes in mammals is achieved in female cells by repressing one of its X chromosomes through a process called X chromosome inactivation (XCI), exemplifying the control of gene expression by epigenetic mechanisms. A critical player in this mechanism is Xist, a long, non-coding RNA upregulated from a single X chromosome during early embryonic development in female cells. Over the past few decades, many factors involved at different levels in the regulation of Xist have been discovered. In this review, we hierarchically describe and analyze the different layers of Xist regulation operating concurrently and intricately interacting with each other to achieve asymmetric and monoallelic upregulation of Xist in murine female cells. We categorize these into five different classes: DNA elements, transcription factors, other regulatory proteins, long non-coding RNAs, and the chromatin and topological landscape surrounding Xist.
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Affiliation(s)
| | - Joost Gribnau
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 GD Rotterdam, The Netherlands
| | - Hegias Mira-Bontenbal
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 GD Rotterdam, The Netherlands
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8
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Keniry A, Blewitt ME. Chromatin-mediated silencing on the inactive X chromosome. Development 2023; 150:dev201742. [PMID: 37991053 DOI: 10.1242/dev.201742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
In mammals, the second X chromosome in females is silenced to enable dosage compensation between XX females and XY males. This essential process involves the formation of a dense chromatin state on the inactive X (Xi) chromosome. There is a wealth of information about the hallmarks of Xi chromatin and the contribution each makes to silencing, leaving the tantalising possibility of learning from this knowledge to potentially remove silencing to treat X-linked diseases in females. Here, we discuss the role of each chromatin feature in the establishment and maintenance of the silent state, which is of crucial relevance for such a goal.
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Affiliation(s)
- Andrew Keniry
- Epigenetics and Development Division, The Walter and Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
- The Department of Medical Biology, University of Melbourne, Parkville, VIC 3010, Australia
| | - Marnie E Blewitt
- Epigenetics and Development Division, The Walter and Eliza Hall Institute for Medical Research, 1G Royal Parade, Parkville, VIC 3052, Australia
- The Department of Medical Biology, University of Melbourne, Parkville, VIC 3010, Australia
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9
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Senapati S, Irshad IU, Sharma AK, Kumar H. Fundamental insights into the correlation between chromosome configuration and transcription. Phys Biol 2023; 20:051002. [PMID: 37467757 DOI: 10.1088/1478-3975/ace8e5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 07/19/2023] [Indexed: 07/21/2023]
Abstract
Eukaryotic chromosomes exhibit a hierarchical organization that spans a spectrum of length scales, ranging from sub-regions known as loops, which typically comprise hundreds of base pairs, to much larger chromosome territories that can encompass a few mega base pairs. Chromosome conformation capture experiments that involve high-throughput sequencing methods combined with microscopy techniques have enabled a new understanding of inter- and intra-chromosomal interactions with unprecedented details. This information also provides mechanistic insights on the relationship between genome architecture and gene expression. In this article, we review the recent findings on three-dimensional interactions among chromosomes at the compartment, topologically associating domain, and loop levels and the impact of these interactions on the transcription process. We also discuss current understanding of various biophysical processes involved in multi-layer structural organization of chromosomes. Then, we discuss the relationships between gene expression and genome structure from perturbative genome-wide association studies. Furthermore, for a better understanding of how chromosome architecture and function are linked, we emphasize the role of epigenetic modifications in the regulation of gene expression. Such an understanding of the relationship between genome architecture and gene expression can provide a new perspective on the range of potential future discoveries and therapeutic research.
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Affiliation(s)
- Swayamshree Senapati
- School of Basic Sciences, Indian Institute of Technology, Bhubaneswar, Argul, Odisha 752050, India
| | - Inayat Ullah Irshad
- Department of Physics, Indian Institute of Technology, Jammu, Jammu 181221, India
| | - Ajeet K Sharma
- Department of Physics, Indian Institute of Technology, Jammu, Jammu 181221, India
- Department of Biosciences and Bioengineering, Indian Institute of Technology Jammu, Jammu 181221, India
| | - Hemant Kumar
- School of Basic Sciences, Indian Institute of Technology, Bhubaneswar, Argul, Odisha 752050, India
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10
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Liu H, Tsai H, Yang M, Li G, Bian Q, Ding G, Wu D, Dai J. Three-dimensional genome structure and function. MedComm (Beijing) 2023; 4:e326. [PMID: 37426677 PMCID: PMC10329473 DOI: 10.1002/mco2.326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 05/31/2023] [Accepted: 06/09/2023] [Indexed: 07/11/2023] Open
Abstract
Linear DNA undergoes a series of compression and folding events, forming various three-dimensional (3D) structural units in mammalian cells, including chromosomal territory, compartment, topologically associating domain, and chromatin loop. These structures play crucial roles in regulating gene expression, cell differentiation, and disease progression. Deciphering the principles underlying 3D genome folding and the molecular mechanisms governing cell fate determination remains a challenge. With advancements in high-throughput sequencing and imaging techniques, the hierarchical organization and functional roles of higher-order chromatin structures have been gradually illuminated. This review systematically discussed the structural hierarchy of the 3D genome, the effects and mechanisms of cis-regulatory elements interaction in the 3D genome for regulating spatiotemporally specific gene expression, the roles and mechanisms of dynamic changes in 3D chromatin conformation during embryonic development, and the pathological mechanisms of diseases such as congenital developmental abnormalities and cancer, which are attributed to alterations in 3D genome organization and aberrations in key structural proteins. Finally, prospects were made for the research about 3D genome structure, function, and genetic intervention, and the roles in disease development, prevention, and treatment, which may offer some clues for precise diagnosis and treatment of related diseases.
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Affiliation(s)
- Hao Liu
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
- School of StomatologyWeifang Medical UniversityWeifangChina
| | - Hsiangyu Tsai
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Maoquan Yang
- School of Clinical MedicineWeifang Medical UniversityWeifangChina
| | - Guozhi Li
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Qian Bian
- Shanghai Institute of Precision MedicineShanghaiChina
| | - Gang Ding
- School of StomatologyWeifang Medical UniversityWeifangChina
| | - Dandan Wu
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
| | - Jiewen Dai
- Department of Oral and Cranio‐Maxillofacial SurgeryShanghai Ninth People's Hospital, Shanghai Jiao Tong University School of MedicineCollege of Stomatology, Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghaiChina
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11
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Schwämmle T, Schulz EG. Regulatory principles and mechanisms governing the onset of random X-chromosome inactivation. Curr Opin Genet Dev 2023; 81:102063. [PMID: 37356341 PMCID: PMC10465972 DOI: 10.1016/j.gde.2023.102063] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 05/23/2023] [Accepted: 05/24/2023] [Indexed: 06/27/2023]
Abstract
X-chromosome inactivation (XCI) has evolved in mammals to compensate for the difference in X-chromosomal dosage between the sexes. In placental mammals, XCI is initiated during early embryonic development through upregulation of the long noncoding RNA Xist from one randomly chosen X chromosome in each female cell. The Xist locus must thus integrate both X-linked and developmental trans-regulatory factors in a dosage-dependent manner. Furthermore, the two alleles must coordinate to ensure inactivation of exactly one X chromosome per cell. In this review, we summarize the regulatory principles that govern the onset of XCI. We go on to provide an overview over the factors that have been implicated in Xist regulation and discuss recent advances in our understanding of how Xist's cis-regulatory landscape integrates information in a precise fashion.
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Affiliation(s)
- Till Schwämmle
- Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, Berlin, Germany. https://twitter.com/@TSchwammle
| | - Edda G Schulz
- Otto Warburg Laboratories, Max Planck Institute for Molecular Genetics, Berlin, Germany.
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12
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Hamley JC, Li H, Denny N, Downes D, Davies JOJ. Determining chromatin architecture with Micro Capture-C. Nat Protoc 2023; 18:1687-1711. [PMID: 36991220 DOI: 10.1038/s41596-023-00817-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 01/11/2023] [Indexed: 03/30/2023]
Abstract
Micro Capture-C (MCC) is a chromatin conformation capture (3C) method for visualizing reproducible three-dimensional contacts of specified regions of the genome at base pair resolution. These methods are an established family of techniques that use proximity ligation to assay the topology of chromatin. MCC can generate data at substantially higher resolution than previous techniques through multiple refinements of the 3C method. Using a sequence agnostic nuclease, the maintenance of cellular integrity and full sequencing of the ligation junctions, MCC achieves subnucleosomal levels of resolution, which can be used to reveal transcription factor binding sites analogous to DNAse I footprinting. Gene dense regions, close-range enhancer-promoter contacts, individual enhancers within super-enhancers and multiple other types of loci or regulatory regions that were previously challenging to assay with conventional 3C techniques, are readily observed using MCC. MCC requires training in common molecular biology techniques and bioinformatics to perform the experiment and analyze the data. The protocol can be expected to be completed in a 3 week timeframe for experienced molecular biologists.
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Affiliation(s)
- Joseph C Hamley
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Hangpeng Li
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Nicholas Denny
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Damien Downes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - James O J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
- Oxford Biomedical Research Centre, Genomic Medicine and Cell and Gene Therapy Themes, Oxford, UK.
- National Institute of Health Research Blood and Transplant Research Unit, Oxford, UK.
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13
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Mattick JS, Amaral PP, Carninci P, Carpenter S, Chang HY, Chen LL, Chen R, Dean C, Dinger ME, Fitzgerald KA, Gingeras TR, Guttman M, Hirose T, Huarte M, Johnson R, Kanduri C, Kapranov P, Lawrence JB, Lee JT, Mendell JT, Mercer TR, Moore KJ, Nakagawa S, Rinn JL, Spector DL, Ulitsky I, Wan Y, Wilusz JE, Wu M. Long non-coding RNAs: definitions, functions, challenges and recommendations. Nat Rev Mol Cell Biol 2023; 24:430-447. [PMID: 36596869 PMCID: PMC10213152 DOI: 10.1038/s41580-022-00566-8] [Citation(s) in RCA: 521] [Impact Index Per Article: 521.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/16/2022] [Indexed: 01/05/2023]
Abstract
Genes specifying long non-coding RNAs (lncRNAs) occupy a large fraction of the genomes of complex organisms. The term 'lncRNAs' encompasses RNA polymerase I (Pol I), Pol II and Pol III transcribed RNAs, and RNAs from processed introns. The various functions of lncRNAs and their many isoforms and interleaved relationships with other genes make lncRNA classification and annotation difficult. Most lncRNAs evolve more rapidly than protein-coding sequences, are cell type specific and regulate many aspects of cell differentiation and development and other physiological processes. Many lncRNAs associate with chromatin-modifying complexes, are transcribed from enhancers and nucleate phase separation of nuclear condensates and domains, indicating an intimate link between lncRNA expression and the spatial control of gene expression during development. lncRNAs also have important roles in the cytoplasm and beyond, including in the regulation of translation, metabolism and signalling. lncRNAs often have a modular structure and are rich in repeats, which are increasingly being shown to be relevant to their function. In this Consensus Statement, we address the definition and nomenclature of lncRNAs and their conservation, expression, phenotypic visibility, structure and functions. We also discuss research challenges and provide recommendations to advance the understanding of the roles of lncRNAs in development, cell biology and disease.
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Affiliation(s)
- John S Mattick
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, NSW, Australia.
- UNSW RNA Institute, UNSW, Sydney, NSW, Australia.
| | - Paulo P Amaral
- INSPER Institute of Education and Research, São Paulo, Brazil
| | - Piero Carninci
- RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
- Human Technopole, Milan, Italy
| | - Susan Carpenter
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Howard Y Chang
- Center for Personal Dynamics Regulomes, Stanford University School of Medicine, Stanford, CA, USA
- Department of Dermatology, Stanford, CA, USA
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Ling-Ling Chen
- CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
| | - Runsheng Chen
- Key Laboratory of RNA Biology, Center for Big Data Research in Health, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Caroline Dean
- John Innes Centre, Norwich Research Park, Norwich, UK
| | - Marcel E Dinger
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, NSW, Australia
- UNSW RNA Institute, UNSW, Sydney, NSW, Australia
| | - Katherine A Fitzgerald
- Division of Innate Immunity, Department of Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | | | - Mitchell Guttman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Tetsuro Hirose
- Graduate School of Frontier Biosciences, Osaka University, Osaka, Japan
| | - Maite Huarte
- Department of Gene Therapy and Regulation of Gene Expression, Center for Applied Medical Research, University of Navarra, Pamplona, Spain
- Institute of Health Research of Navarra, Pamplona, Spain
| | - Rory Johnson
- School of Biology and Environmental Science, University College Dublin, Dublin, Ireland
- Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Dublin, Ireland
| | - Chandrasekhar Kanduri
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Philipp Kapranov
- Institute of Genomics, School of Medicine, Huaqiao University, Xiamen, China
| | - Jeanne B Lawrence
- Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Jeannie T Lee
- Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - Joshua T Mendell
- Howard Hughes Medical Institute, UT Southwestern Medical Center, Dallas, TX, USA
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Timothy R Mercer
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane, QLD, Australia
| | - Kathryn J Moore
- Department of Medicine, New York University Grossman School of Medicine, New York, NY, USA
| | - Shinichi Nakagawa
- RNA Biology Laboratory, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan
| | - John L Rinn
- Department of Biochemistry, University of Colorado Boulder, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado Boulder, Boulder, CO, USA
- Howard Hughes Medical Institute, University of Colorado Boulder, Boulder, CO, USA
| | - David L Spector
- Cold Spring Harbour Laboratory, Cold Spring Harbour, NY, USA
| | - Igor Ulitsky
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Yue Wan
- Laboratory of RNA Genomics and Structure, Genome Institute of Singapore, A*STAR, Singapore, Singapore
- Department of Biochemistry, National University of Singapore, Singapore, Singapore
| | - Jeremy E Wilusz
- Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Therapeutic Innovation Center, Baylor College of Medicine, Houston, TX, USA
| | - Mian Wu
- Translational Research Institute, Henan Provincial People's Hospital, Academy of Medical Science, Zhengzhou University, Zhengzhou, China
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14
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Uyehara CM, Apostolou E. 3D enhancer-promoter interactions and multi-connected hubs: Organizational principles and functional roles. Cell Rep 2023; 42:112068. [PMID: 37059094 PMCID: PMC10556201 DOI: 10.1016/j.celrep.2023.112068] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 11/25/2022] [Accepted: 01/20/2023] [Indexed: 04/16/2023] Open
Abstract
The spatiotemporal control of gene expression is dependent on the activity of cis-acting regulatory sequences, called enhancers, which regulate target genes over variable genomic distances and, often, by skipping intermediate promoters, suggesting mechanisms that control enhancer-promoter communication. Recent genomics and imaging technologies have revealed highly complex enhancer-promoter interaction networks, whereas advanced functional studies have started interrogating the forces behind the physical and functional communication among multiple enhancers and promoters. In this review, we first summarize our current understanding of the factors involved in enhancer-promoter communication, with a particular focus on recent papers that have revealed new layers of complexities to old questions. In the second part of the review, we focus on a subset of highly connected enhancer-promoter "hubs" and discuss their potential functions in signal integration and gene regulation, as well as the putative factors that might determine their dynamics and assembly.
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Affiliation(s)
- Christopher M Uyehara
- Sanford I. Weill Department of Medicine, Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10021, USA
| | - Effie Apostolou
- Sanford I. Weill Department of Medicine, Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10021, USA.
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15
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Chakraborty S, Kopitchinski N, Zuo Z, Eraso A, Awasthi P, Chari R, Mitra A, Tobias IC, Moorthy SD, Dale RK, Mitchell JA, Petros TJ, Rocha PP. Enhancer-promoter interactions can bypass CTCF-mediated boundaries and contribute to phenotypic robustness. Nat Genet 2023; 55:280-290. [PMID: 36717694 PMCID: PMC10758292 DOI: 10.1038/s41588-022-01295-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 12/20/2022] [Indexed: 01/31/2023]
Abstract
How enhancers activate their distal target promoters remains incompletely understood. Here we dissect how CTCF-mediated loops facilitate and restrict such regulatory interactions. Using an allelic series of mouse mutants, we show that CTCF is neither required for the interaction of the Sox2 gene with distal enhancers, nor for its expression. Insertion of various combinations of CTCF motifs, between Sox2 and its distal enhancers, generated boundaries with varying degrees of insulation that directly correlated with reduced transcriptional output. However, in both epiblast and neural tissues, enhancer contacts and transcriptional induction could not be fully abolished, and insertions failed to disrupt implantation and neurogenesis. In contrast, Sox2 expression was undetectable in the anterior foregut of mutants carrying the strongest boundaries, and these animals fully phenocopied loss of SOX2 in this tissue. We propose that enhancer clusters with a high density of regulatory activity can better overcome physical barriers to maintain faithful gene expression and phenotypic robustness.
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Affiliation(s)
- Shreeta Chakraborty
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Nina Kopitchinski
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Zhenyu Zuo
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Ariel Eraso
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Parirokh Awasthi
- Laboratory Animal Sciences Program, Frederick National Lab for Cancer Research, Frederick, MD, USA
| | - Raj Chari
- Laboratory Animal Sciences Program, Frederick National Lab for Cancer Research, Frederick, MD, USA
| | - Apratim Mitra
- Bioinformatics and Scientific Programming Core, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Ian C Tobias
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Sakthi D Moorthy
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Ryan K Dale
- Bioinformatics and Scientific Programming Core, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Jennifer A Mitchell
- Department of Cell and Systems Biology, University of Toronto, Toronto, Ontario, Canada
| | - Timothy J Petros
- Unit on Cellular and Molecular Neurodevelopment, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Pedro P Rocha
- Unit on Genome Structure and Regulation, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
- National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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16
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Bauer M, Payer B, Filion GJ. Causality in transcription and genome folding: Insights from X inactivation. Bioessays 2022; 44:e2200105. [PMID: 36028473 DOI: 10.1002/bies.202200105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/11/2022] [Accepted: 08/14/2022] [Indexed: 11/10/2022]
Abstract
The spatial organization of genomes is becoming increasingly understood. In mammals, where it is most investigated, this organization ties in with transcription, so an important research objective is to understand whether gene activity is a cause or a consequence of genome folding in space. In this regard, the phenomena of X-chromosome inactivation and reactivation open a unique window of investigation because of the singularities of the inactive X chromosome. Here we focus on the cause-consequence nexus between genome conformation and transcription and explain how recent results about the structural changes associated with inactivation and reactivation of the X chromosome shed light on this problem.
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Affiliation(s)
- Moritz Bauer
- Oncode Institute, Hubrecht Institute-KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bernhard Payer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Guillaume J Filion
- Dept. Biological Sciences, University of Toronto Scarborough, Toronto, ON, Canada
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17
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A proposed unified interphase nucleus chromosome structure: Preliminary preponderance of evidence. Proc Natl Acad Sci U S A 2022; 119:e2119101119. [PMID: 35749363 PMCID: PMC9245672 DOI: 10.1073/pnas.2119101119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cryopreservation of the nuclear interior allows a large-scale interphase chromosome structure—present throughout the nucleus—to be seen in its native state by electron tomography. This structure appears as a coiled chain of nucleosomes, wrapped like a Slinky toy. This coiled structure can be further used to explain the enigmatic architectures of polytene and lampbrush chromosomes. In addition, this new structure can further be organized as chromosome territories: for example, all 46 human interphase chromosomes easily fit into a 10-μm-diameter nucleus. Thus, interphase chromosomes can be unified into a flexibly defined structure. Cryoelectron tomography of the cell nucleus using scanning transmission electron microscopy and deconvolution processing technology has highlighted a large-scale, 100- to 300-nm interphase chromosome structure, which is present throughout the nucleus. This study further documents and analyzes these chromosome structures. The paper is divided into four parts: 1) evidence (preliminary) for a unified interphase chromosome structure; 2) a proposed unified interphase chromosome architecture; 3) organization as chromosome territories (e.g., fitting the 46 human chromosomes into a 10-μm-diameter nucleus); and 4) structure unification into a polytene chromosome architecture and lampbrush chromosomes. Finally, the paper concludes with a living light microscopy cell study showing that the G1 nucleus contains very similar structures throughout. The main finding is that this chromosome structure appears to coil the 11-nm nucleosome fiber into a defined hollow structure, analogous to a Slinky helical spring [https://en.wikipedia.org/wiki/Slinky; motif used in Bowerman et al., eLife 10, e65587 (2021)]. This Slinky architecture can be used to build chromosome territories, extended to the polytene chromosome structure, as well as to the structure of lampbrush chromosomes.
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18
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Chromosome organization affects genome evolution in Sulfolobus archaea. Nat Microbiol 2022; 7:820-830. [PMID: 35618771 DOI: 10.1038/s41564-022-01127-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 04/21/2022] [Indexed: 12/16/2022]
Abstract
In all organisms, the DNA sequence and the structural organization of chromosomes affect gene expression. The extremely thermophilic crenarchaeon Sulfolobus has one circular chromosome with three origins of replication. We previously revealed that this chromosome has defined A and B compartments that have high and low gene expression, respectively. As well as higher levels of gene expression, the A compartment contains the origins of replication. To evaluate the impact of three-dimensional organization on genome evolution, we characterized the effect of replication origins and compartmentalization on primary sequence evolution in eleven Sulfolobus species. Using single-nucleotide polymorphism analyses, we found that distance from an origin of replication was associated with increased mutation rates in the B but not in the A compartment. The enhanced polymorphisms distal to replication origins suggest that replication termination may have a causal role in their generation. Further mutational analyses revealed that the sequences in the A compartment are less likely to be mutated, and that there is stronger purifying selection than in the B compartment. Finally, we applied the Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) to show that the B compartment is less accessible than the A compartment. Taken together, our data suggest that compartmentalization of chromosomal DNA can influence chromosome evolution in Sulfolobus. We propose that the A compartment serves as a haven for stable maintenance of gene sequences, while sequences in the B compartment can be diversified.
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19
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Dossin F, Heard E. The Molecular and Nuclear Dynamics of X-Chromosome Inactivation. Cold Spring Harb Perspect Biol 2022; 14:a040196. [PMID: 34312245 PMCID: PMC9121902 DOI: 10.1101/cshperspect.a040196] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
In female eutherian mammals, dosage compensation of X-linked gene expression is achieved during development through transcriptional silencing of one of the two X chromosomes. Following X chromosome inactivation (XCI), the inactive X chromosome remains faithfully silenced throughout somatic cell divisions. XCI is dependent on Xist, a long noncoding RNA that coats and silences the X chromosome from which it is transcribed. Xist coating triggers a cascade of chromosome-wide changes occurring at the levels of transcription, chromatin composition, chromosome structure, and spatial organization within the nucleus. XCI has emerged as a paradigm for the study of such crucial nuclear processes and the dissection of their functional interplay. In the past decade, the advent of tools to characterize and perturb these processes have provided an unprecedented understanding into their roles during XCI. The mechanisms orchestrating the initiation of XCI as well as its maintenance are thus being unraveled, although many questions still remain. Here, we introduce key aspects of the XCI process and review the recent discoveries about its molecular basis.
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Affiliation(s)
- François Dossin
- European Molecular Biology Laboratory, Director's Unit, 69117 Heidelberg, Germany
| | - Edith Heard
- European Molecular Biology Laboratory, Director's Unit, 69117 Heidelberg, Germany
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20
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Galupa R, Picard C, Servant N, Nora EP, Zhan Y, van Bemmel JG, El Marjou F, Johanneau C, Borensztein M, Ancelin K, Giorgetti L, Heard E. Inversion of a topological domain leads to restricted changes in its gene expression and affects interdomain communication. Development 2022; 149:275259. [PMID: 35502750 PMCID: PMC9148567 DOI: 10.1242/dev.200568] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 02/28/2022] [Indexed: 01/02/2023]
Abstract
The interplay between the topological organization of the genome and the regulation of gene expression remains unclear. Depletion of molecular factors (e.g. CTCF) underlying topologically associating domains (TADs) leads to modest alterations in gene expression, whereas genomic rearrangements involving TAD boundaries disrupt normal gene expression and can lead to pathological phenotypes. Here, we targeted the TAD neighboring that of the noncoding transcript Xist, which controls X-chromosome inactivation. Inverting 245 kb within the TAD led to expected rearrangement of CTCF-based contacts but revealed heterogeneity in the 'contact' potential of different CTCF sites. Expression of most genes therein remained unaffected in mouse embryonic stem cells and during differentiation. Interestingly, expression of Xist was ectopically upregulated. The same inversion in mouse embryos led to biased Xist expression. Smaller inversions and deletions of CTCF clusters led to similar results: rearrangement of contacts and limited changes in local gene expression, but significant changes in Xist expression in embryos. Our study suggests that the wiring of regulatory interactions within a TAD can influence the expression of genes in neighboring TADs, highlighting the existence of mechanisms of inter-TAD communication.
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Affiliation(s)
- Rafael Galupa
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | - Christel Picard
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | - Nicolas Servant
- Bioinformatics, Biostatistics, Epidemiology and Computational Systems Unit, Institut Curie, PSL Research University, INSERM U900, Paris 75005, France.,MINES ParisTech, PSL Research University, CBIO-Centre for Computational Biology, Paris 75006, France
| | - Elphège P Nora
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | - Yinxiu Zhan
- Friedrich Miescher Institute for Biomedical Research, Basel 4058, Switzerland.,University of Basel, Basel 4001, Switzerland
| | - Joke G van Bemmel
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | | | | | - Maud Borensztein
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | - Katia Ancelin
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France
| | - Luca Giorgetti
- Friedrich Miescher Institute for Biomedical Research, Basel 4058, Switzerland
| | - Edith Heard
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris 75005, France.,Collège de France, Paris 75231, France
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21
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Hoyt SJ, Storer JM, Hartley GA, Grady PGS, Gershman A, de Lima LG, Limouse C, Halabian R, Wojenski L, Rodriguez M, Altemose N, Rhie A, Core LJ, Gerton JL, Makalowski W, Olson D, Rosen J, Smit AFA, Straight AF, Vollger MR, Wheeler TJ, Schatz MC, Eichler EE, Phillippy AM, Timp W, Miga KH, O’Neill RJ. From telomere to telomere: The transcriptional and epigenetic state of human repeat elements. Science 2022; 376:eabk3112. [PMID: 35357925 PMCID: PMC9301658 DOI: 10.1126/science.abk3112] [Citation(s) in RCA: 121] [Impact Index Per Article: 60.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mobile elements and repetitive genomic regions are sources of lineage-specific genomic innovation and uniquely fingerprint individual genomes. Comprehensive analyses of such repeat elements, including those found in more complex regions of the genome, require a complete, linear genome assembly. We present a de novo repeat discovery and annotation of the T2T-CHM13 human reference genome. We identified previously unknown satellite arrays, expanded the catalog of variants and families for repeats and mobile elements, characterized classes of complex composite repeats, and located retroelement transduction events. We detected nascent transcription and delineated CpG methylation profiles to define the structure of transcriptionally active retroelements in humans, including those in centromeres. These data expand our insight into the diversity, distribution, and evolution of repetitive regions that have shaped the human genome.
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Affiliation(s)
- Savannah J. Hoyt
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | | | - Gabrielle A. Hartley
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Patrick G. S. Grady
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Ariel Gershman
- Department of Molecular Biology and Genetics, Johns Hopkins University, Baltimore, MD, USA
| | | | - Charles Limouse
- Department of Biochemistry, Stanford University, Stanford, CA, USA
| | - Reza Halabian
- Institute of Bioinformatics, Faculty of Medicine, University of Münster, Münster, Germany
| | - Luke Wojenski
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
| | - Matias Rodriguez
- Institute of Bioinformatics, Faculty of Medicine, University of Münster, Münster, Germany
| | - Nicolas Altemose
- Department of Bioengineering, University of California, Berkeley, Berkeley, CA, USA
| | - Arang Rhie
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Leighton J. Core
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
| | | | - Wojciech Makalowski
- Institute of Bioinformatics, Faculty of Medicine, University of Münster, Münster, Germany
| | - Daniel Olson
- Department of Computer Science, University of Montana, Missoula, MT, USA
| | - Jeb Rosen
- Institute for Systems Biology, Seattle, WA, USA
| | | | | | - Mitchell R. Vollger
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Travis J. Wheeler
- Department of Computer Science, University of Montana, Missoula, MT, USA
| | - Michael C. Schatz
- Department of Computer Science and Department of Biology, Johns Hopkins University, Baltimore, MD, USA
| | - Evan E. Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Adam M. Phillippy
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Winston Timp
- Department of Molecular Biology and Genetics, Johns Hopkins University, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Karen H. Miga
- UC Santa Cruz Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - Rachel J. O’Neill
- Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA
- Institute for Systems Genomics, University of Connecticut, Storrs, CT, USA
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
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22
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Mechanisms of Choice in X-Chromosome Inactivation. Cells 2022; 11:cells11030535. [PMID: 35159344 PMCID: PMC8833938 DOI: 10.3390/cells11030535] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/30/2022] [Accepted: 01/31/2022] [Indexed: 12/04/2022] Open
Abstract
Early in development, placental and marsupial mammals harbouring at least two X chromosomes per nucleus are faced with a choice that affects the rest of their lives: which of those X chromosomes to transcriptionally inactivate. This choice underlies phenotypical diversity in the composition of tissues and organs and in their response to the environment, and can determine whether an individual will be healthy or affected by an X-linked disease. Here, we review our current understanding of the process of choice during X-chromosome inactivation and its implications, focusing on the strategies evolved by different mammalian lineages and on the known and unknown molecular mechanisms and players involved.
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23
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Downes DJ, Smith AL, Karpinska MA, Velychko T, Rue-Albrecht K, Sims D, Milne TA, Davies JOJ, Oudelaar AM, Hughes JR. Capture-C: a modular and flexible approach for high-resolution chromosome conformation capture. Nat Protoc 2022; 17:445-475. [PMID: 35121852 PMCID: PMC7613269 DOI: 10.1038/s41596-021-00651-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/27/2021] [Indexed: 12/16/2022]
Abstract
Chromosome conformation capture (3C) methods measure the spatial proximity between DNA elements in the cell nucleus. Many methods have been developed to sample 3C material, including the Capture-C family of protocols. Capture-C methods use oligonucleotides to enrich for interactions of interest from sequencing-ready 3C libraries. This approach is modular and has been adapted and optimized to work for sampling of disperse DNA elements (NuTi Capture-C), including from low cell inputs (LI Capture-C), as well as to generate Hi-C like maps for specific regions of interest (Tiled-C) and to interrogate multiway interactions (Tri-C). We present the design, experimental protocol and analysis pipeline for NuTi Capture-C in addition to the variations for generation of LI Capture-C, Tiled-C and Tri-C data. The entire procedure can be performed in 3 weeks and requires standard molecular biology skills and equipment, access to a next-generation sequencing platform, and basic bioinformatic skills. Implemented with other sequencing technologies, these methods can be used to identify regulatory interactions and to compare the structural organization of the genome in different cell types and genetic models.
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Affiliation(s)
- Damien J Downes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Alastair L Smith
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | | | - Taras Velychko
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Kevin Rue-Albrecht
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - David Sims
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Thomas A Milne
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- NIHR Oxford Biomedical Research Centre, Haematology Theme, Oxford, UK
| | - James O J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | | | - Jim R Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
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24
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Faber MW, Vo TV. Long RNA-Mediated Chromatin Regulation in Fission Yeast and Mammals. Int J Mol Sci 2022; 23:968. [PMID: 35055152 PMCID: PMC8778201 DOI: 10.3390/ijms23020968] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 12/12/2022] Open
Abstract
As part of a complex network of genome control, long regulatory RNAs exert significant influences on chromatin dynamics. Understanding how this occurs could illuminate new avenues for disease treatment and lead to new hypotheses that would advance gene regulatory research. Recent studies using the model fission yeast Schizosaccharomyces pombe (S. pombe) and powerful parallel sequencing technologies have provided many insights in this area. This review will give an overview of key findings in S. pombe that relate long RNAs to multiple levels of chromatin regulation: histone modifications, gene neighborhood regulation in cis and higher-order chromosomal ordering. Moreover, we discuss parallels recently found in mammals to help bridge the knowledge gap between the study systems.
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Affiliation(s)
| | - Tommy V. Vo
- Department of Biochemistry and Molecular Biology, College of Human Medicine, Michigan State University, East Lansing, MI 48824, USA;
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25
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Gene regulation in time and space during X-chromosome inactivation. Nat Rev Mol Cell Biol 2022; 23:231-249. [PMID: 35013589 DOI: 10.1038/s41580-021-00438-7] [Citation(s) in RCA: 93] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/18/2021] [Indexed: 12/21/2022]
Abstract
X-chromosome inactivation (XCI) is the epigenetic mechanism that ensures X-linked dosage compensation between cells of females (XX karyotype) and males (XY). XCI is essential for female embryos to survive through development and requires the accurate spatiotemporal regulation of many different factors to achieve remarkable chromosome-wide gene silencing. As a result of XCI, the active and inactive X chromosomes are functionally and structurally different, with the inactive X chromosome undergoing a major conformational reorganization within the nucleus. In this Review, we discuss the multiple layers of genetic and epigenetic regulation that underlie initiation of XCI during development and then maintain it throughout life, in light of the most recent findings in this rapidly advancing field. We discuss exciting new insights into the regulation of X inactive-specific transcript (XIST), the trigger and master regulator of XCI, and into the mechanisms and dynamics that underlie the silencing of nearly all X-linked genes. Finally, given the increasing interest in understanding the impact of chromosome organization on gene regulation, we provide an overview of the factors that are thought to reshape the 3D structure of the inactive X chromosome and of the relevance of such structural changes for XCI establishment and maintenance.
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26
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Nora EP. Lesson of regulatory anatomy: Using integrated functional genomics to dissect the X-inactivation center. Mol Cell 2022; 82:10-12. [PMID: 34995506 DOI: 10.1016/j.molcel.2021.12.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Gjaltema et al. (2021) perform systematic screens to identify the long-sought cis-regulatory elements of Xist. They discover that distal elements give Xist a boost as cells exit pluripotency, while proximal elements restrict Xist expression to cells with two X chromosomes.
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Affiliation(s)
- Elphège P Nora
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA; Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA.
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27
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Oh HJ, Aguilar R, Kesner B, Lee HG, Kriz AJ, Chu HP, Lee JT. Jpx RNA regulates CTCF anchor site selection and formation of chromosome loops. Cell 2021; 184:6157-6173.e24. [PMID: 34856126 DOI: 10.1016/j.cell.2021.11.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 09/22/2021] [Accepted: 11/09/2021] [Indexed: 01/24/2023]
Abstract
Chromosome loops shift dynamically during development, homeostasis, and disease. CCCTC-binding factor (CTCF) is known to anchor loops and construct 3D genomes, but how anchor sites are selected is not yet understood. Here, we unveil Jpx RNA as a determinant of anchor selectivity. Jpx RNA targets thousands of genomic sites, preferentially binding promoters of active genes. Depleting Jpx RNA causes ectopic CTCF binding, massive shifts in chromosome looping, and downregulation of >700 Jpx target genes. Without Jpx, thousands of lost loops are replaced by de novo loops anchored by ectopic CTCF sites. Although Jpx controls CTCF binding on a genome-wide basis, it acts selectively at the subset of developmentally sensitive CTCF sites. Specifically, Jpx targets low-affinity CTCF motifs and displaces CTCF protein through competitive inhibition. We conclude that Jpx acts as a CTCF release factor and shapes the 3D genome by regulating anchor site usage.
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Affiliation(s)
- Hyun Jung Oh
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Rodrigo Aguilar
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Barry Kesner
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Hun-Goo Lee
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Andrea J Kriz
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Hsueh-Ping Chu
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA
| | - Jeannie T Lee
- Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA.
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28
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Damián A, Ionescu RO, Rodríguez de Alba M, Tamayo A, Trujillo-Tiebas MJ, Cotarelo-Pérez MC, Pérez Rodríguez O, Villaverde C, de la Fuente L, Romero R, Núñez-Moreno G, Mínguez P, Ayuso C, Cortón M. Fine Breakpoint Mapping by Genome Sequencing Reveals the First Large X Inversion Disrupting the NHS Gene in a Patient with Syndromic Cataracts. Int J Mol Sci 2021; 22:ijms222312713. [PMID: 34884523 PMCID: PMC8657747 DOI: 10.3390/ijms222312713] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022] Open
Abstract
Inversions are structural variants that are generally balanced. However, they could lead to gene disruptions or have positional effects leading to diseases. Mutations in the NHS gene cause Nance-Horan syndrome, an X-linked disorder characterised by congenital cataracts and dental anomalies. Here, we aimed to characterise a balanced pericentric inversion X(p22q27), maternally inherited, in a child with syndromic bilateral cataracts by breakpoint mapping using whole-genome sequencing (WGS). 30× Illumina paired-end WGS was performed in the proband, and breakpoints were confirmed by Sanger sequencing. EdU assays and FISH analysis were used to assess skewed X-inactivation patterns. RNA expression of involved genes in the breakpoint boundaries was evaluated by droplet-digital PCR. We defined the breakpoint position of the inversion at Xp22.13, with a 15 bp deletion, disrupting the unusually large intron 1 of the canonical NHS isoform, and also perturbing topologically-associated domains (TADs). Moreover, a microhomology region of 5 bp was found on both sides. RNA analysis confirmed null and reduced NHS expression in the proband and his unaffected mother, respectively. In conclusion, we report the first chromosomal inversion disrupting NHS, fine-mapped by WGS. Our data expand the clinical spectrum and the pathogenic mechanisms underlying the NHS defects.
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Affiliation(s)
- Alejandra Damián
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - Raluca Oancea Ionescu
- Department of Medical Genetics, University Hospital Clínico San Carlos, 28040 Madrid, Spain; (R.O.I.); (M.C.C.P.)
| | - Marta Rodríguez de Alba
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - Alejandra Tamayo
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - María José Trujillo-Tiebas
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - María Carmen Cotarelo-Pérez
- Department of Medical Genetics, University Hospital Clínico San Carlos, 28040 Madrid, Spain; (R.O.I.); (M.C.C.P.)
| | - Olga Pérez Rodríguez
- Department of Pediatrics, University Hospital Clínico San Carlos, 28040 Madrid, Spain;
| | - Cristina Villaverde
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - Lorena de la Fuente
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
- Bioinformatics Unit, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040, Madrid, Spain
| | - Raquel Romero
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - Gonzalo Núñez-Moreno
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Bioinformatics Unit, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040, Madrid, Spain
| | - Pablo Mínguez
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
- Bioinformatics Unit, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040, Madrid, Spain
| | - Carmen Ayuso
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
| | - Marta Cortón
- Department of Genetics & Genomics, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), 28040 Madrid, Spain; (A.D.); (M.R.d.A.); (A.T.); (M.J.T.-T); (C.V.); (L.d.l.F.); (R.R.); (G.N.-M); (P.M.); (C.A.)
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), 28290 Madrid, Spain
- Correspondence:
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29
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Ridnik M, Schoenfelder S, Gonen N. Cis-Regulatory Control of Mammalian Sex Determination. Sex Dev 2021; 15:317-334. [PMID: 34710870 PMCID: PMC8743899 DOI: 10.1159/000519244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 08/10/2021] [Indexed: 11/19/2022] Open
Abstract
Sex determination is the process by which an initial bipotential gonad adopts either a testicular or ovarian cell fate. The inability to properly complete this process leads to a group of developmental disorders classified as disorders of sex development (DSD). To date, dozens of genes were shown to play roles in mammalian sex determination, and mutations in these genes can cause DSD in humans or gonadal sex reversal/dysfunction in mice. However, exome sequencing currently provides genetic diagnosis for only less than half of DSD patients. This points towards a major role for the non-coding genome during sex determination. In this review, we highlight recent advances in our understanding of non-coding, cis-acting gene regulatory elements and discuss how they may control transcriptional programmes that underpin sex determination in the context of the 3-dimensional folding of chromatin. As a paradigm, we focus on the Sox9 gene, a prominent pro-male factor and one of the most extensively studied genes in gonadal cell fate determination.
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Affiliation(s)
- Meshi Ridnik
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
- Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
| | - Stefan Schoenfelder
- Epigenetics Programme, The Babraham Institute, Babraham Research Campus, Cambridge, United Kingdom
| | - Nitzan Gonen
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
- Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat Gan, Israel
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30
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Abstract
Nuclei are central hubs for information processing in eukaryotic cells. The need to fit large genomes into small nuclei imposes severe restrictions on genome organization and the mechanisms that drive genome-wide regulatory processes. How a disordered polymer such as chromatin, which has vast heterogeneity in its DNA and histone modification profiles, folds into discernibly consistent patterns is a fundamental question in biology. Outstanding questions include how genomes are spatially and temporally organized to regulate cellular processes with high precision and whether genome organization is causally linked to transcription regulation. The advent of next-generation sequencing, super-resolution imaging, multiplexed fluorescent in situ hybridization, and single-molecule imaging in individual living cells has caused a resurgence in efforts to understand the spatiotemporal organization of the genome. In this review, we discuss structural and mechanistic properties of genome organization at different length scales and examine changes in higher-order chromatin organization during important developmental transitions.
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Affiliation(s)
- Rajarshi P Ghosh
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California 94720, USA; ,
| | - Barbara J Meyer
- Department of Molecular and Cell Biology and Howard Hughes Medical Institute, University of California, Berkeley, California 94720, USA; ,
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31
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A Novel cis Regulatory Element Regulates Human XIST in a CTCF-Dependent Manner. Mol Cell Biol 2021; 41:e0038220. [PMID: 34060915 DOI: 10.1128/mcb.00382-20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The long noncoding RNA XIST is the master regulator for the process of X chromosome inactivation (XCI) in mammalian females. Here, we report the existence of a hitherto-uncharacterized cis regulatory element (cRE) within the first exon of human XIST, which determines the transcriptional status of XIST during the initiation and maintenance phases of XCI. In the initiation phase, pluripotency factors bind to this cRE and keep XIST repressed. In the maintenance phase of XCI, the cRE is enriched for CTCF, which activates XIST transcription. By employing a CRISPR-dCas9-KRAB-based interference strategy, we demonstrate that binding of CTCF to the newly identified cRE is critical for regulating XIST in a YY1-dependent manner. Collectively, our study uncovers the combinatorial effect of multiple transcriptional regulators influencing XIST expression during the initiation and maintenance phases of XCI.
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Shen Y, Lin Y, Liu K, Chen J, Zhong J, Gao Y, Yuan C. XIST: A Meaningful Long Noncoding RNA in NSCLC Process. Curr Pharm Des 2021; 27:1407-1417. [PMID: 33267757 DOI: 10.2174/1381612826999201202102413] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 11/01/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND A number of studies have proposed that lncRNA XIST plays a role in the development and chemosensitivity of NSCLC. Besides, XIST may become a potential therapeutic target for NSCLC patients. The aim of this review is to reveal the biological functions and exact mechanisms of XIST in NSCLC. METHODS In this review, relevant researches involving the relationship between XIST and NSCLC are collected through systematic retrieval of PubMed. RESULTS XIST is an oncogene in NSCLC and is abnormally upregulated in NSCLC tissues. Considerable evidence has shown that XIST plays a critical role in the proliferation, invasion, migration, apoptosis and chemosensitivity of NSCLC cells. XIST mainly functions as a ceRNA in the NSCLC process, while XIST also functions at transcriptional levels. CONCLUSION LncRNA XIST has the potential to become a novel biomolecular marker of NSCLC and a therapeutic target for NSCLC.
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Affiliation(s)
- Yujie Shen
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Yexiang Lin
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Kai Liu
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Jinlan Chen
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Juanjuan Zhong
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Yisong Gao
- College of Medical Science, China Three Gorges University, Yichang 443002, China
| | - Chengfu Yuan
- College of Medical Science, China Three Gorges University, Yichang 443002, China
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Wang W, Min L, Qiu X, Wu X, Liu C, Ma J, Zhang D, Zhu L. Biological Function of Long Non-coding RNA (LncRNA) Xist. Front Cell Dev Biol 2021; 9:645647. [PMID: 34178980 PMCID: PMC8222981 DOI: 10.3389/fcell.2021.645647] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 05/12/2021] [Indexed: 12/24/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) regulate gene expression in a variety of ways at epigenetic, chromatin remodeling, transcriptional, and translational levels. Accumulating evidence suggests that lncRNA X-inactive specific transcript (lncRNA Xist) serves as an important regulator of cell growth and development. Despites its original roles in X-chromosome dosage compensation, lncRNA Xist also participates in the development of tumor and other human diseases by functioning as a competing endogenous RNA (ceRNA). In this review, we comprehensively summarized recent progress in understanding the cellular functions of lncRNA Xist in mammalian cells and discussed current knowledge regarding the ceRNA network of lncRNA Xist in various diseases. Long non-coding RNAs (lncRNAs) are transcripts that are more than 200 nt in length and without an apparent protein-coding capacity (Furlan and Rougeulle, 2016; Maduro et al., 2016). These RNAs are believed to be transcribed by the approximately 98-99% non-coding regions of the human genome (Derrien et al., 2012; Fu, 2014; Montalbano et al., 2017; Slack and Chinnaiyan, 2019), as well as a large variety of genomic regions, such as exonic, tronic, and intergenic regions. Hence, lncRNAs are also divided into eight categories: Intergenic lncRNAs, Intronic lncRNAs, Enhancer lncRNAs, Promoter lncRNAs, Natural antisense/sense lncRNAs, Small nucleolar RNA-ended lncRNAs (sno-lncRNAs), Bidirectional lncRNAs, and non-poly(A) lncRNAs (Ma et al., 2013; Devaux et al., 2015; St Laurent et al., 2015; Chen, 2016; Quinn and Chang, 2016; Richard and Eichhorn, 2018; Connerty et al., 2020). A range of evidence has suggested that lncRNAs function as key regulators in crucial cellular functions, including proliferation, differentiation, apoptosis, migration, and invasion, by regulating the expression level of target genes via epigenomic, transcriptional, or post-transcriptional approaches (Cao et al., 2018). Moreover, lncRNAs detected in body fluids were also believed to serve as potential biomarkers for the diagnosis, prognosis, and monitoring of disease progression, and act as novel and potential drug targets for therapeutic exploitation in human disease (Jiang W. et al., 2018; Zhou et al., 2019a). Long non-coding RNA X-inactive specific transcript (lncRNA Xist) are a set of 15,000-20,000 nt sequences localized in the X chromosome inactivation center (XIC) of chromosome Xq13.2 (Brown et al., 1992; Debrand et al., 1998; Kay, 1998; Lee et al., 2013; da Rocha and Heard, 2017; Yang Z. et al., 2018; Brockdorff, 2019). Previous studies have indicated that lncRNA Xist regulate X chromosome inactivation (XCI), resulting in the inheritable silencing of one of the X-chromosomes during female cell development. Also, it serves a vital regulatory function in the whole spectrum of human disease (notably cancer) and can be used as a novel diagnostic and prognostic biomarker and as a potential therapeutic target for human disease in the clinic (Liu et al., 2018b; Deng et al., 2019; Dinescu et al., 2019; Mutzel and Schulz, 2020; Patrat et al., 2020; Wang et al., 2020a). In particular, lncRNA Xist have been demonstrated to be involved in the development of multiple types of tumors including brain tumor, Leukemia, lung cancer, breast cancer, and liver cancer, with the prominent examples outlined in Table 1. It was also believed that lncRNA Xist (Chaligne and Heard, 2014; Yang Z. et al., 2018) contributed to other diseases, such as pulmonary fibrosis, inflammation, neuropathic pain, cardiomyocyte hypertrophy, and osteoarthritis chondrocytes, and more specific details can be found in Table 2. This review summarizes the current knowledge on the regulatory mechanisms of lncRNA Xist on both chromosome dosage compensation and pathogenesis (especially cancer) processes, with a focus on the regulatory network of lncRNA Xist in human disease.
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Affiliation(s)
| | | | | | | | | | | | - Dongyi Zhang
- Department of Biology and Chemistry, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, China
| | - Lingyun Zhu
- Department of Biology and Chemistry, College of Liberal Arts and Sciences, National University of Defense Technology, Changsha, China
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34
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Chromosome compartments on the inactive X guide TAD formation independently of transcription during X-reactivation. Nat Commun 2021; 12:3499. [PMID: 34108480 PMCID: PMC8190187 DOI: 10.1038/s41467-021-23610-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 05/10/2021] [Indexed: 12/21/2022] Open
Abstract
A hallmark of chromosome organization is the partition into transcriptionally active A and repressed B compartments, and into topologically associating domains (TADs). Both structures were regarded to be absent from the inactive mouse X chromosome, but to be re-established with transcriptional reactivation and chromatin opening during X-reactivation. Here, we combine a tailor-made mouse iPSC reprogramming system and high-resolution Hi-C to produce a time course combining gene reactivation, chromatin opening and chromosome topology during X-reactivation. Contrary to previous observations, we observe A/B-like compartments on the inactive X harbouring multiple subcompartments. While partial X-reactivation initiates within a compartment rich in X-inactivation escapees, it then occurs rapidly along the chromosome, concomitant with downregulation of Xist. Importantly, we find that TAD formation precedes transcription and initiates from Xist-poor compartments. Here, we show that TAD formation and transcriptional reactivation are causally independent during X-reactivation while establishing Xist as a common denominator.
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35
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Zhang D, Lam J, Blobel GA. Engineering three-dimensional genome folding. Nat Genet 2021; 53:602-611. [PMID: 33958782 DOI: 10.1038/s41588-021-00860-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Accepted: 03/29/2021] [Indexed: 02/02/2023]
Abstract
Animal genomes are partitioned and folded at various scales that contribute distinctly to nuclear processes. While structural features have been disrupted either globally or at select loci in loss-of-function studies, gain-of-function studies that probe the role of genome architecture have lagged behind. Here we examine recent advances in experimentally creating chromatin loops, contact domains, boundaries and compartments. Furthermore, we explore parallels between this emerging theme and natural evolution of mammalian genomes with increasing architectural complexity. Finally, we provide a perspective on how insights arising from recent gain-of-function studies may inform future endeavors toward engineering the three-dimensional genome.
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Affiliation(s)
- Di Zhang
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jessica Lam
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Gerd A Blobel
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA. .,Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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36
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Xiang JF, Corces VG. Regulation of 3D chromatin organization by CTCF. Curr Opin Genet Dev 2021; 67:33-40. [PMID: 33259986 PMCID: PMC8084898 DOI: 10.1016/j.gde.2020.10.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/18/2020] [Accepted: 10/26/2020] [Indexed: 01/12/2023]
Abstract
Studies of nuclear architecture using chromosome conformation capture methods have provided a detailed view of how chromatin folds in the 3D nuclear space. New variants of this technology now afford unprecedented resolution and allow the identification of ever smaller folding domains that offer new insights into the mechanisms by which this organization is established and maintained. Here we review recent results in this rapidly evolving field with an emphasis on CTCF function, with the goal of gaining a mechanistic understanding of the principles by which chromatin is folded in the eukaryotic nucleus.
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Affiliation(s)
- Jian-Feng Xiang
- Emory University School of Medicine, Department of Human Genetics, 615 Michael Street, Atlanta, GA 30322, USA
| | - Victor G Corces
- Emory University School of Medicine, Department of Human Genetics, 615 Michael Street, Atlanta, GA 30322, USA.
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37
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Tracing DNA paths and RNA profiles in cultured cells and tissues with ORCA. Nat Protoc 2021; 16:1647-1713. [PMID: 33619390 PMCID: PMC8525907 DOI: 10.1038/s41596-020-00478-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 11/26/2020] [Indexed: 01/31/2023]
Abstract
Chromatin conformation capture (3C) methods and fluorescent in situ hybridization (FISH) microscopy have been used to investigate the spatial organization of the genome. Although powerful, both techniques have limitations. Hi-C is challenging for low cell numbers and requires very deep sequencing to achieve its high resolution. In contrast, FISH can be done on small cell numbers and capture rare cell populations, but typically targets pairs of loci at a lower resolution. Here we detail a protocol for optical reconstruction of chromatin architecture (ORCA), a microscopy approach to trace the 3D DNA path within the nuclei of fixed tissues and cultured cells with a genomic resolution as fine as 2 kb and a throughput of ~10,000 cells per experiment. ORCA can identify structural features with comparable resolution to Hi-C while providing single-cell resolution and multimodal measurements characteristic of microscopy. We describe how to use this DNA labeling in parallel with multiplexed labeling of dozens of RNAs to relate chromatin structure and gene expression in the same cells. Oligopaint probe design, primary probe making, sample collection, cryosectioning and RNA/DNA primary probe hybridization can be completed in 1.5 weeks, while automated RNA/DNA barcode hybridization and RNA/DNA imaging typically takes 2-6 d for data collection and 2-7 d for the automated steps of image analysis.
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38
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Cavalheiro GR, Pollex T, Furlong EE. To loop or not to loop: what is the role of TADs in enhancer function and gene regulation? Curr Opin Genet Dev 2021; 67:119-129. [PMID: 33497970 DOI: 10.1016/j.gde.2020.12.015] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 12/13/2020] [Accepted: 12/22/2020] [Indexed: 01/22/2023]
Abstract
The past decade has seen a huge jump in the resolution and scale at which we can interrogate the three-dimensional properties of the genome. This revealed different types of chromatin structures including topologically associating domains, partitioning genes and their enhancers into interacting domains. While the visualisation of these topologies and their dynamics has dramatically improved, our understanding of their underlying mechanisms and functional roles in gene expression has lagged behind. A suite of recent studies have addressed this using genetic manipulations to perturb topological features and loops at different scales. Here we assess the new biological insights gained on the functional relationship between genome topology and gene expression, with a particular focus on enhancer function.
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Affiliation(s)
- Gabriel R Cavalheiro
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, D-69117, Heidelberg, Germany; Collaboration for Joint PhD Degree Between EMBL and Heidelberg University, Faculty of Biosciences, Germany
| | - Tim Pollex
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, D-69117, Heidelberg, Germany
| | - Eileen Em Furlong
- European Molecular Biology Laboratory (EMBL), Genome Biology Unit, D-69117, Heidelberg, Germany.
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39
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Downes DJ, Beagrie RA, Gosden ME, Telenius J, Carpenter SJ, Nussbaum L, De Ornellas S, Sergeant M, Eijsbouts CQ, Schwessinger R, Kerry J, Roberts N, Shivalingam A, El-Sagheer A, Oudelaar AM, Brown T, Buckle VJ, Davies JOJ, Hughes JR. High-resolution targeted 3C interrogation of cis-regulatory element organization at genome-wide scale. Nat Commun 2021; 12:531. [PMID: 33483495 PMCID: PMC7822813 DOI: 10.1038/s41467-020-20809-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 12/16/2020] [Indexed: 01/30/2023] Open
Abstract
Chromosome conformation capture (3C) provides an adaptable tool for studying diverse biological questions. Current 3C methods generally provide either low-resolution interaction profiles across the entire genome, or high-resolution interaction profiles at limited numbers of loci. Due to technical limitations, generation of reproducible high-resolution interaction profiles has not been achieved at genome-wide scale. Here, to overcome this barrier, we systematically test each step of 3C and report two improvements over current methods. We show that up to 30% of reporter events generated using the popular in situ 3C method arise from ligations between two individual nuclei, but this noise can be almost entirely eliminated by isolating intact nuclei after ligation. Using Nuclear-Titrated Capture-C, we generate reproducible high-resolution genome-wide 3C interaction profiles by targeting 8055 gene promoters in erythroid cells. By pairing high-resolution 3C interaction calls with nascent gene expression we interrogate the role of promoter hubs and super-enhancers in gene regulation.
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Affiliation(s)
- Damien J Downes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Robert A Beagrie
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Matthew E Gosden
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jelena Telenius
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Stephanie J Carpenter
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Lea Nussbaum
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Sara De Ornellas
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Martin Sergeant
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Chris Q Eijsbouts
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Ron Schwessinger
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jon Kerry
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Nigel Roberts
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Arun Shivalingam
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Afaf El-Sagheer
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - A Marieke Oudelaar
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Tom Brown
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Veronica J Buckle
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - James O J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jim R Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK.
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40
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Ramírez-Colmenero A, Oktaba K, Fernandez-Valverde SL. Evolution of Genome-Organizing Long Non-coding RNAs in Metazoans. Front Genet 2020; 11:589697. [PMID: 33329735 PMCID: PMC7734150 DOI: 10.3389/fgene.2020.589697] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 11/09/2020] [Indexed: 12/28/2022] Open
Abstract
Long non-coding RNAs (lncRNAs) have important regulatory functions across eukarya. It is now clear that many of these functions are related to gene expression regulation through their capacity to recruit epigenetic modifiers and establish chromatin interactions. Several lncRNAs have been recently shown to participate in modulating chromatin within the spatial organization of the genome in the three-dimensional space of the nucleus. The identification of lncRNA candidates is challenging, as it is their functional characterization. Conservation signatures of lncRNAs are different from those of protein-coding genes, making identifying lncRNAs under selection a difficult task, and the homology between lncRNAs may not be readily apparent. Here, we review the evidence for these higher-order genome organization functions of lncRNAs in animals and the evolutionary signatures they display.
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Affiliation(s)
- América Ramírez-Colmenero
- Unidad de Genómica Avanzada (Langebio), Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, México
| | - Katarzyna Oktaba
- Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, México
| | - Selene L Fernandez-Valverde
- Unidad de Genómica Avanzada (Langebio), Centro de Investigación y de Estudios Avanzados del IPN, Irapuato, México
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41
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Panda A, Zylicz JJ, Pasque V. New Insights into X-Chromosome Reactivation during Reprogramming to Pluripotency. Cells 2020; 9:E2706. [PMID: 33348832 PMCID: PMC7766869 DOI: 10.3390/cells9122706] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 02/06/2023] Open
Abstract
Dosage compensation between the sexes results in one X chromosome being inactivated during female mammalian development. Chromosome-wide transcriptional silencing from the inactive X chromosome (Xi) in mammalian cells is erased in a process termed X-chromosome reactivation (XCR), which has emerged as a paradigm for studying the reversal of chromatin silencing. XCR is linked with germline development and induction of naive pluripotency in the epiblast, and also takes place upon reprogramming somatic cells to induced pluripotency. XCR depends on silencing of the long non-coding RNA (lncRNA) X inactive specific transcript (Xist) and is linked with the erasure of chromatin silencing. Over the past years, the advent of transcriptomics and epigenomics has provided new insights into the transcriptional and chromatin dynamics with which XCR takes place. However, multiple questions remain unanswered about how chromatin and transcription related processes enable XCR. Here, we review recent work on establishing the transcriptional and chromatin kinetics of XCR, as well as discuss a model by which transcription factors mediate XCR not only via Xist repression, but also by direct targeting of X-linked genes.
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Affiliation(s)
- Amitesh Panda
- Laboratory of Cellular Reprogramming and Epigenetic Regulation, Department of Development and Regeneration, Leuven Stem Cell Institute, KU Leuven-University of Leuven, 3000 Leuven, Belgium;
| | - Jan J. Zylicz
- The Novo Nordisk Foundation Center for Stem Cell Biology, University of Copenhagen, 2200 Copenhagen, Denmark;
| | - Vincent Pasque
- Laboratory of Cellular Reprogramming and Epigenetic Regulation, Department of Development and Regeneration, Leuven Stem Cell Institute, KU Leuven-University of Leuven, 3000 Leuven, Belgium;
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42
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Rodríguez-Carballo E, Lopez-Delisle L, Willemin A, Beccari L, Gitto S, Mascrez B, Duboule D. Chromatin topology and the timing of enhancer function at the HoxD locus. Proc Natl Acad Sci U S A 2020; 117:31231-31241. [PMID: 33229569 PMCID: PMC7733857 DOI: 10.1073/pnas.2015083117] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The HoxD gene cluster is critical for proper limb formation in tetrapods. In the emerging limb buds, different subgroups of Hoxd genes respond first to a proximal regulatory signal, then to a distal signal that organizes digits. These two regulations are exclusive from one another and emanate from two distinct topologically associating domains (TADs) flanking HoxD, both containing a range of appropriate enhancer sequences. The telomeric TAD (T-DOM) contains several enhancers active in presumptive forearm cells and is divided into two sub-TADs separated by a CTCF-rich boundary, which defines two regulatory submodules. To understand the importance of this particular regulatory topology to control Hoxd gene transcription in time and space, we either deleted or inverted this sub-TAD boundary, eliminated the CTCF binding sites, or inverted the entire T-DOM to exchange the respective positions of the two sub-TADs. The effects of such perturbations on the transcriptional regulation of Hoxd genes illustrate the requirement of this regulatory topology for the precise timing of gene activation. However, the spatial distribution of transcripts was eventually resumed, showing that the presence of enhancer sequences, rather than either their exact topology or a particular chromatin architecture, is the key factor. We also show that the affinity of enhancers to find their natural target genes can overcome the presence of both a strong TAD border and an unfavorable orientation of CTCF sites.
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Affiliation(s)
| | - Lucille Lopez-Delisle
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Andréa Willemin
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland
| | - Leonardo Beccari
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland
| | - Sandra Gitto
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland
| | - Bénédicte Mascrez
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland
| | - Denis Duboule
- Department of Genetics and Evolution, University of Geneva, 1211 Geneva, Switzerland;
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
- Collège de France, 75005 Paris, France
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43
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Hansen AS. CTCF as a boundary factor for cohesin-mediated loop extrusion: evidence for a multi-step mechanism. Nucleus 2020; 11:132-148. [PMID: 32631111 PMCID: PMC7566886 DOI: 10.1080/19491034.2020.1782024] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/01/2020] [Accepted: 06/05/2020] [Indexed: 01/10/2023] Open
Abstract
Mammalian genome structure is closely linked to function. At the scale of kilobases to megabases, CTCF and cohesin organize the genome into chromatin loops. Mechanistically, cohesin is proposed to extrude chromatin loops bidirectionally until it encounters occupied CTCF DNA-binding sites. Curiously, loops form predominantly between CTCF binding sites in a convergent orientation. How CTCF interacts with and blocks cohesin extrusion in an orientation-specific manner has remained a mechanistic mystery. Here, we review recent papers that have shed light on these processes and suggest a multi-step interaction between CTCF and cohesin. This interaction may first involve a pausing step, where CTCF halts cohesin extrusion, followed by a stabilization step of the CTCF-cohesin complex, resulting in a chromatin loop. Finally, we discuss our own recent studies on an internal RNA-Binding Region (RBRi) in CTCF to elucidate its role in regulating CTCF clustering, target search mechanisms and chromatin loop formation and future challenges.
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Affiliation(s)
- Anders S. Hansen
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
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44
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Nora EP, Caccianini L, Fudenberg G, So K, Kameswaran V, Nagle A, Uebersohn A, Hajj B, Saux AL, Coulon A, Mirny LA, Pollard KS, Dahan M, Bruneau BG. Molecular basis of CTCF binding polarity in genome folding. Nat Commun 2020; 11:5612. [PMID: 33154377 PMCID: PMC7645679 DOI: 10.1038/s41467-020-19283-x] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 10/07/2020] [Indexed: 11/09/2022] Open
Abstract
Current models propose that boundaries of mammalian topologically associating domains (TADs) arise from the ability of the CTCF protein to stop extrusion of chromatin loops by cohesin. While the orientation of CTCF motifs determines which pairs of CTCF sites preferentially stabilize loops, the molecular basis of this polarity remains unclear. By combining ChIP-seq and single molecule live imaging we report that CTCF positions cohesin, but does not control its overall binding dynamics on chromatin. Using an inducible complementation system, we find that CTCF mutants lacking the N-terminus cannot insulate TADs properly. Cohesin remains at CTCF sites in this mutant, albeit with reduced enrichment. Given the orientation of CTCF motifs presents the N-terminus towards cohesin as it translocates from the interior of TADs, these observations explain how the orientation of CTCF binding sites translates into genome folding patterns.
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Affiliation(s)
- Elphège P Nora
- Gladstone Institutes, San Francisco, CA, 94158, USA.
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA, 94158, USA.
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, 94143, USA.
- Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, 94143, USA.
| | - Laura Caccianini
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR168, 26 Rue D'Ulm, Paris, 75005, France
| | | | - Kevin So
- Gladstone Institutes, San Francisco, CA, 94158, USA
| | - Vasumathi Kameswaran
- Gladstone Institutes, San Francisco, CA, 94158, USA
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA, 94158, USA
| | - Abigail Nagle
- Gladstone Institutes, San Francisco, CA, 94158, USA
- University of Washington, Seattle, WA, USA
| | - Alec Uebersohn
- Gladstone Institutes, San Francisco, CA, 94158, USA
- University of California Berkeley, Berkeley, CA, USA
| | - Bassam Hajj
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR168, 26 Rue D'Ulm, Paris, 75005, France
| | - Agnès Le Saux
- Institut Curie, PSL Research University, CNRS UMR 3215, INSERM U934, Mammalian Developmental Epigenetics group, F-75005, Paris, France
- Sorbonne Université, F-75005, Paris, France
| | - Antoine Coulon
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR168, 26 Rue D'Ulm, Paris, 75005, France
- Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR3664, Nuclear Dynamics unit, F-75005, Paris, France
| | - Leonid A Mirny
- Institute for Medical Engineering and Science and Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Katherine S Pollard
- Gladstone Institutes, San Francisco, CA, 94158, USA
- Department of Epidemiology & Biostatistics, Institute for Human Genetics, Quantitative Biology Institute, and Institute for Computational Health Sciences, University of California San Francisco, San Francisco, CA, USA
- Chan Zuckerberg Biohub, San Francisco, CA, USA
| | - Maxime Dahan
- Laboratoire Physico Chimie Curie, Institut Curie, PSL Research University, Sorbonne Université, CNRS UMR168, 26 Rue D'Ulm, Paris, 75005, France
| | - Benoit G Bruneau
- Gladstone Institutes, San Francisco, CA, 94158, USA.
- Roddenberry Center for Stem Cell Biology and Medicine at Gladstone, San Francisco, CA, 94158, USA.
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, 94143, USA.
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, 94143, USA.
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45
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Mizi A, Zhang S, Papantonis A. Genome folding and refolding in differentiation and cellular senescence. Curr Opin Cell Biol 2020; 67:56-63. [PMID: 32911122 DOI: 10.1016/j.ceb.2020.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 08/02/2020] [Accepted: 08/03/2020] [Indexed: 12/11/2022]
Abstract
The spatial conformation of chromatin within the confines of eukaryotic cell nuclei is now acknowledged as a decisive epigenetic mechanism for the modulation of such cellular functions as gene expression regulation, DNA replication or DNA damage repair. Of course, these processes are tightly regulated during organismal development and markedly affected by cellular ageing. Thus, the question that arises is to what extent does folding or refolding of the genome in three-dimensional space underlie the progression of development or ageing? Herein, we discuss recent experimental and modelling evidence to address this question and revisit how these seemingly different processed might represent two sides of the same coin.
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Affiliation(s)
- Athanasia Mizi
- Institute of Pathology, University Medical Center Göttingen, 37075, Göttingen, Germany
| | - Shu Zhang
- 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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46
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Enhancer-Promoter Communication: Thinking Outside the TAD. Trends Genet 2020; 36:459-461. [PMID: 32544446 DOI: 10.1016/j.tig.2020.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 04/08/2020] [Indexed: 01/03/2023]
Abstract
How does the folding of the genome relate to the regulation of gene expression? Using fly embryos and quantitative live imaging, a recent study by Yokoshi et al. reveals that the answer might depend on whether enhancer-promoter communication occurs inside or in-between topological domains.
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47
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Ibrahim DM, Mundlos S. Three-dimensional chromatin in disease: What holds us together and what drives us apart? Curr Opin Cell Biol 2020; 64:1-9. [DOI: 10.1016/j.ceb.2020.01.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/22/2019] [Accepted: 01/06/2020] [Indexed: 12/27/2022]
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48
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Ibrahim DM, Mundlos S. The role of 3D chromatin domains in gene regulation: a multi-facetted view on genome organization. Curr Opin Genet Dev 2020; 61:1-8. [PMID: 32199341 DOI: 10.1016/j.gde.2020.02.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/06/2020] [Accepted: 02/07/2020] [Indexed: 02/06/2023]
Abstract
The causal relationship between 3D chromatin domains and gene regulation has been of considerable debate in recent years. Initial Hi-C studies profiling the 3D chromatin structure of the genome described evolutionarily conserved Topologically Associating Domains (TADs) that correlated with gene expression. Subsequent evidence from mouse models and human disease directly linked TADs to gene regulation. However, a number of focused genetic and genome-wide studies questioned the relevance of 3D chromatin domains for orchestrating gene expression, ultimately yielding a more multi-layered view of 3D chromatin structure and gene regulation. We review the evidence for and against the importance of 3D chromatin structure for gene regulation and argue for a more comprehensive classification of regulatory chromatin domains that integrates 3D chromatin structure with genomic, functional, and evolutionary conservation.
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Affiliation(s)
- Daniel M Ibrahim
- RG Development & Disease, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany; Institute for Medical and Human Genetics, Charité Universitätsmedizin Berlin, 13353 Berlin, Germany; Charité - Universitätsmedizin Berlin, BCRT - Berlin Institute of Health Center for Regenerative Therapies, 10178 Berlin, Germany.
| | - Stefan Mundlos
- RG Development & Disease, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany; Institute for Medical and Human Genetics, Charité Universitätsmedizin Berlin, 13353 Berlin, Germany; Charité - Universitätsmedizin Berlin, BCRT - Berlin Institute of Health Center for Regenerative Therapies, 10178 Berlin, Germany.
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49
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Galupa R, Nora EP, Worsley-Hunt R, Picard C, Gard C, van Bemmel JG, Servant N, Zhan Y, El Marjou F, Johanneau C, Diabangouaya P, Le Saux A, Lameiras S, Pipoli da Fonseca J, Loos F, Gribnau J, Baulande S, Ohler U, Giorgetti L, Heard E. A Conserved Noncoding Locus Regulates Random Monoallelic Xist Expression across a Topological Boundary. Mol Cell 2020; 77:352-367.e8. [PMID: 31759823 PMCID: PMC6964159 DOI: 10.1016/j.molcel.2019.10.030] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 09/08/2019] [Accepted: 10/17/2019] [Indexed: 12/11/2022]
Abstract
cis-Regulatory communication is crucial in mammalian development and is thought to be restricted by the spatial partitioning of the genome in topologically associating domains (TADs). Here, we discovered that the Xist locus is regulated by sequences in the neighboring TAD. In particular, the promoter of the noncoding RNA Linx (LinxP) acts as a long-range silencer and influences the choice of X chromosome to be inactivated. This is independent of Linx transcription and independent of any effect on Tsix, the antisense regulator of Xist that shares the same TAD as Linx. Unlike Tsix, LinxP is well conserved across mammals, suggesting an ancestral mechanism for random monoallelic Xist regulation. When introduced in the same TAD as Xist, LinxP switches from a silencer to an enhancer. Our study uncovers an unsuspected regulatory axis for X chromosome inactivation and a class of cis-regulatory effects that may exploit TAD partitioning to modulate developmental decisions.
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Affiliation(s)
- Rafael Galupa
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Elphège Pierre Nora
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Rebecca Worsley-Hunt
- Berlin Institute for Medical Systems Biology, Max Delbruck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Christel Picard
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Chris Gard
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Joke Gerarda van Bemmel
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Nicolas Servant
- Bioinformatics, Biostatistics, Epidemiology and Computational Systems Unit, Institut Curie, PSL Research University, INSERM U900, Paris, France; MINES ParisTech, PSL Research University, Centre for Computational Biology (CBIO), Paris, France
| | - Yinxiu Zhan
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland; University of Basel, Basel, Switzerland
| | | | | | - Patricia Diabangouaya
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Agnès Le Saux
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France
| | - Sonia Lameiras
- Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie, Paris, France
| | | | - Friedemann Loos
- Department of Developmental Biology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands
| | - Joost Gribnau
- Department of Developmental Biology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands
| | - Sylvain Baulande
- Institut Curie Genomics of Excellence (ICGex) Platform, Institut Curie, Paris, France
| | - Uwe Ohler
- Berlin Institute for Medical Systems Biology, Max Delbruck Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany; Department of Biology, Humboldt University, Berlin, Germany
| | - Luca Giorgetti
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Edith Heard
- Mammalian Developmental Epigenetics Group, Genetics and Developmental Biology Unit, Institut Curie, PSL Research University, CNRS UMR3215, INSERM U934, Paris, France; Collège de France, Paris, France.
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Beagan JA, Phillips-Cremins JE. On the existence and functionality of topologically associating domains. Nat Genet 2020; 52:8-16. [PMID: 31925403 PMCID: PMC7567612 DOI: 10.1038/s41588-019-0561-1] [Citation(s) in RCA: 206] [Impact Index Per Article: 51.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Accepted: 11/25/2019] [Indexed: 01/01/2023]
Abstract
Genomes across a wide range of eukaryotic organisms fold into higher-order chromatin domains. Topologically associating domains (TADs) were originally discovered empirically in low-resolution Hi-C heat maps representing ensemble average interaction frequencies from millions of cells. Here, we discuss recent advances in high-resolution Hi-C, single-cell imaging experiments, and functional genetic studies, which provide an increasingly complex view of the genome's hierarchical structure-function relationship. On the basis of these new findings, we update the definitions of distinct classes of chromatin domains according to emerging knowledge of their structural, mechanistic and functional properties.
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Affiliation(s)
- Jonathan A Beagan
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Jennifer E Phillips-Cremins
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
- Epigenetics Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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