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Xu M, Ito-Kureha T, Kang HS, Chernev A, Raj T, Hoefig KP, Hohn C, Giesert F, Wang Y, Pan W, Ziętara N, Straub T, Feederle R, Daniel C, Adler B, König J, Feske S, Tsokos GC, Wurst W, Urlaub H, Sattler M, Kisielow J, Wulczyn FG, Łyszkiewicz M, Heissmeyer V. The thymocyte-specific RNA-binding protein Arpp21 provides TCR repertoire diversity by binding to the 3'-UTR and promoting Rag1 mRNA expression. Nat Commun 2024; 15:2194. [PMID: 38467629 PMCID: PMC10928157 DOI: 10.1038/s41467-024-46371-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 02/26/2024] [Indexed: 03/13/2024] Open
Abstract
The regulation of thymocyte development by RNA-binding proteins (RBPs) is largely unexplored. We identify 642 RBPs in the thymus and focus on Arpp21, which shows selective and dynamic expression in early thymocytes. Arpp21 is downregulated in response to T cell receptor (TCR) and Ca2+ signals. Downregulation requires Stim1/Stim2 and CaMK4 expression and involves Arpp21 protein phosphorylation, polyubiquitination and proteasomal degradation. Arpp21 directly binds RNA through its R3H domain, with a preference for uridine-rich motifs, promoting the expression of target mRNAs. Analysis of the Arpp21-bound transcriptome reveals strong interactions with the Rag1 3'-UTR. Arpp21-deficient thymocytes show reduced Rag1 expression, delayed TCR rearrangement and a less diverse TCR repertoire. This phenotype is recapitulated in Rag1 3'-UTR mutant mice harboring a deletion of the Arpp21 response region. These findings show how thymocyte-specific Arpp21 promotes Rag1 expression to enable TCR repertoire diversity until signals from the TCR terminate Arpp21 and Rag1 activities.
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Affiliation(s)
- Meng Xu
- Research Unit Molecular Immune Regulation, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Munich, Germany
- Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Taku Ito-Kureha
- Institute for Immunology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany
| | - Hyun-Seo Kang
- Institute of Structural Biology, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Neuherberg, Germany
- Technical University of Munich, TUM School of Natural Sciences, Department of Bioscience and Bavarian NMR Center (BNMRZ), Garching, Germany
| | - Aleksandar Chernev
- Max Planck Institute for Multidisciplinary Sciences, Bioanalytical Mass Spectrometry, Göttingen, Germany
| | - Timsse Raj
- Institute for Immunology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany
| | - Kai P Hoefig
- Research Unit Molecular Immune Regulation, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Munich, Germany
| | - Christine Hohn
- Institute for Immunology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany
| | - Florian Giesert
- Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Yinhu Wang
- Department of Pathology, New York University, Grossman School of Medicine, New York, NY, USA
| | - Wenliang Pan
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Natalia Ziętara
- Institute for Immunology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany
- Cancer Immunology and Immune Modulation, Boehringer Ingelheim Pharma GmbH & Co. KG, Biberach an der Riss, Germany
| | - Tobias Straub
- Institute for Molecular Biology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany
| | - Regina Feederle
- Monoclonal Antibody Core Facility, German Research Center for Environmental Health, Neuherberg, Germany
| | - Carolin Daniel
- Research Unit Type 1 Diabetes Immunology, Helmholtz Diabetes Center at Helmholtz Zentrum München, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Division of Clinical Pharmacology, Department of Medicine IV, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Barbara Adler
- Max von Pettenkofer Institute, Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Munich, Germany
| | - Julian König
- Institute of Molecular Biology (IMB), Mainz, Germany
| | - Stefan Feske
- Department of Pathology, New York University, Grossman School of Medicine, New York, NY, USA
| | - George C Tsokos
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München, Neuherberg, Germany
- Chair of Developmental Genetics, Munich School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
- Munich Cluster of Systems Neurology (SyNergy), Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE) site Munich, Munich, Germany
| | - Henning Urlaub
- Max Planck Institute for Multidisciplinary Sciences, Bioanalytical Mass Spectrometry, Göttingen, Germany
- University Medical Center Göttingen, Department of Clinical Chemistry, Bioanalytics Group, Göttingen, Germany
- Göttingen Center for Molecular Biosciences, Georg-August University Göttingen, Göttingen, Germany
- Cluster of Excellence 'Multiscale Bioimaging: from Molecular Machines to Networks of Excitable Cells' (MBExC), University of Göttingen, Göttingen, Germany
| | - Michael Sattler
- Institute of Structural Biology, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Neuherberg, Germany
- Technical University of Munich, TUM School of Natural Sciences, Department of Bioscience and Bavarian NMR Center (BNMRZ), Garching, Germany
| | - Jan Kisielow
- Institute for Molecular Health Sciences, ETH Zürich, Zürich, Switzerland.
- Repertoire Immune Medicines (Switzerland) AG, Schlieren, Switzerland.
| | - F Gregory Wulczyn
- Institute for Integrative Neuroanatomie, Charite-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.
| | - Marcin Łyszkiewicz
- Research Unit Molecular Immune Regulation, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Munich, Germany.
- Department of Pediatrics and Adolescent Medicine, University Medical Center Ulm, Ulm, Germany.
| | - Vigo Heissmeyer
- Research Unit Molecular Immune Regulation, Molecular Targets and Therapeutics Center, Helmholtz Zentrum München, Munich, Germany.
- Institute for Immunology, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität in Munich, Planegg-Martinsried, Germany.
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2
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Gao Z, Wang M, Smith A, Boyes J. YY1 Binding to Regulatory Elements That Lack Enhancer Activity Promotes Locus Folding and Gene Activation. J Mol Biol 2023; 435:168315. [PMID: 37858706 DOI: 10.1016/j.jmb.2023.168315] [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: 08/14/2023] [Revised: 09/25/2023] [Accepted: 10/12/2023] [Indexed: 10/21/2023]
Abstract
Enhancers activate their cognate promoters over huge distances but how enhancer/promoter interactions become established is not completely understood. There is strong evidence that cohesin-mediated loop extrusion is involved but this does not appear to be a universal mechanism. Here, we identify an element within the mouse immunoglobulin lambda (Igλ) light chain locus, HSCλ1, that has characteristics of active regulatory elements but lacks intrinsic enhancer or promoter activity. Remarkably, knock-out of the YY1 binding site from HSCλ1 reduces Igλ transcription significantly and disrupts enhancer/promoter interactions, even though these elements are >10 kb from HSCλ1. Genome-wide analyses of mouse embryonic stem cells identified 2671 similar YY1-bound, putative genome organizing elements that lie within CTCF/cohesin loop boundaries but that lack intrinsic enhancer activity. We suggest that such elements play a fundamental role in locus folding and in facilitating enhancer/promoter interactions.
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Affiliation(s)
- Zeqian Gao
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Miao Wang
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Alastair Smith
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Joan Boyes
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
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3
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Gao Z, Smith AL, Scott JF, Bevington S, Boyes J. Temporal analyses reveal a pivotal role for sense and antisense enhancer RNAs in coordinate immunoglobulin lambda locus activation. Nucleic Acids Res 2023; 51:10344-10363. [PMID: 37702072 PMCID: PMC10602925 DOI: 10.1093/nar/gkad741] [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] [Received: 03/16/2023] [Revised: 08/24/2023] [Accepted: 08/30/2023] [Indexed: 09/14/2023] Open
Abstract
Transcription enhancers are essential activators of V(D)J recombination that orchestrate non-coding transcription through complementary, unrearranged gene segments. How transcription is coordinately increased at spatially distinct promoters, however, remains poorly understood. Using the murine immunoglobulin lambda (Igλ) locus as model, we find that three enhancer-like elements in the 3' Igλ domain, Eλ3-1, HSCλ1 and HSE-1, show strikingly similar transcription factor binding dynamics and close spatial proximity, suggesting that they form an active enhancer hub. Temporal analyses show coordinate recruitment of complementary V and J gene segments to this hub, with comparable transcription factor binding dynamics to that at enhancers. We find further that E2A, p300, Mediator and Integrator bind to enhancers as early events, whereas YY1 recruitment and eRNA synthesis occur later, corresponding to transcription activation. Remarkably, the interplay between sense and antisense enhancer RNA is central to both active enhancer hub formation and coordinate Igλ transcription: Antisense Eλ3-1 eRNA represses Igλ activation whereas temporal analyses demonstrate that accumulating levels of sense eRNA boost YY1 recruitment to stabilise enhancer hub/promoter interactions and lead to coordinate transcription activation. These studies therefore demonstrate for the first time a critical role for threshold levels of sense versus antisense eRNA in locus activation.
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Affiliation(s)
- Zeqian Gao
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Alastair L Smith
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - James N F Scott
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Sarah L Bevington
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Joan Boyes
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
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4
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Mihai A, Roy S, Krangel MS, Zhuang Y. E protein binding at the Tcra enhancer promotes Tcra repertoire diversity. Front Immunol 2023; 14:1188738. [PMID: 37483636 PMCID: PMC10358851 DOI: 10.3389/fimmu.2023.1188738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 06/21/2023] [Indexed: 07/25/2023] Open
Abstract
V(D)J recombination of antigen receptor loci is a highly developmentally regulated process. During T lymphocyte development, recombination of the Tcra gene occurs in CD4+CD8+ double positive (DP) thymocytes and requires the Tcra enhancer (Eα). E proteins are known regulators of DP thymocyte development and have three identified binding sites in Eα. To understand the contribution of E proteins to Eα function, mutants lacking one or two of the respective binding sites were generated. The double-binding site mutant displayed a partial block at the positive selection stage of αβ T cell development. Further investigation revealed loss of germline transcription within the Tcra locus at the Jα array, along with dysregulated primary and impaired secondary Vα-Jα rearrangement. Eα E protein binding increases Tcra locus accessibility and regulates TCRα recombination, thus directly promoting Tcra repertoire diversity.
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Affiliation(s)
| | | | - Michael S. Krangel
- Department of Immunology, Duke University School of Medicine, Durham, NC, United States
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5
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Sun S, Wijanarko K, Liani O, Strumila K, Ng ES, Elefanty AG, Stanley EG. Lymphoid cell development from fetal hematopoietic progenitors and human pluripotent stem cells. Immunol Rev 2023; 315:154-170. [PMID: 36939073 PMCID: PMC10952469 DOI: 10.1111/imr.13197] [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: 03/21/2023]
Abstract
Lymphoid cells encompass the adaptive immune system, including T and B cells and Natural killer T cells (NKT), and innate immune cells (ILCs), including Natural Killer (NK) cells. During adult life, these lineages are thought to derive from the differentiation of long-term hematopoietic stem cells (HSCs) residing in the bone marrow. However, during embryogenesis and fetal development, the ontogeny of lymphoid cells is both complex and multifaceted, with a large body of evidence suggesting that lymphoid lineages arise from progenitor cell populations antedating the emergence of HSCs. Recently, the application of single cell RNA-sequencing technologies and pluripotent stem cell-based developmental models has provided new insights into lymphoid ontogeny during embryogenesis. Indeed, PSC differentiation platforms have enabled de novo generation of lymphoid immune cells independently of HSCs, supporting conclusions drawn from the study of hematopoiesis in vivo. Here, we examine lymphoid development from non-HSC progenitor cells and technological advances in the differentiation of human lymphoid cells from pluripotent stem cells for clinical translation.
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Affiliation(s)
- Shicheng Sun
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Kevin Wijanarko
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Oniko Liani
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Kathleen Strumila
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Elizabeth S. Ng
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Andrew G. Elefanty
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Edouard G. Stanley
- Murdoch Children's Research InstituteThe Royal Children's HospitalParkvilleVictoriaAustralia
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health SciencesUniversity of MelbourneParkvilleVictoriaAustralia
- The Novo Nordisk Foundation Center for Stem Cell Medicine (reNEW), Murdoch Children's Research InstituteParkvilleVictoriaAustralia
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6
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Barajas-Mora EM, Lee L, Lu H, Valderrama JA, Bjanes E, Nizet V, Feeney AJ, Hu M, Murre C. Enhancer-instructed epigenetic landscape and chromatin compartmentalization dictate a primary antibody repertoire protective against specific bacterial pathogens. Nat Immunol 2023; 24:320-336. [PMID: 36717722 PMCID: PMC10917333 DOI: 10.1038/s41590-022-01402-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 12/06/2022] [Indexed: 01/31/2023]
Abstract
Antigen receptor loci are organized into variable (V), diversity (D) and joining (J) gene segments that rearrange to generate antigen receptor repertoires. Here, we identified an enhancer (E34) in the murine immunoglobulin kappa (Igk) locus that instructed rearrangement of Vκ genes located in a sub-topologically associating domain, including a Vκ gene encoding for antibodies targeting bacterial phosphorylcholine. We show that E34 instructs the nuclear repositioning of the E34 sub-topologically associating domain from a recombination-repressive compartment to a recombination-permissive compartment that is marked by equivalent activating histone modifications. Finally, we found that E34-instructed Vκ-Jκ rearrangement was essential to combat Streptococcus pneumoniae but not methicillin-resistant Staphylococcus aureus or influenza infections. We propose that the merging of Vκ genes with Jκ elements is instructed by one-dimensional epigenetic information imposed by enhancers across Vκ and Jκ genomic regions. The data also reveal how enhancers generate distinct antibody repertoires that provide protection against lethal bacterial infection.
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Affiliation(s)
| | - Lindsay Lee
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Hanbin Lu
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA, USA
| | - J Andrés Valderrama
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Elisabet Bjanes
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Victor Nizet
- Department of Pediatrics, University of California, San Diego, La Jolla, CA, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, USA
| | - Ann J Feeney
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA, USA
| | - Ming Hu
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, USA.
| | - Cornelis Murre
- Department of Molecular Biology, University of California, San Diego, La Jolla, CA, USA.
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7
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Anderson MK, da Rocha JDB. Direct regulation of TCR rearrangement and expression by E proteins during early T cell development. WIREs Mech Dis 2022; 14:e1578. [PMID: 35848146 PMCID: PMC9669112 DOI: 10.1002/wsbm.1578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/22/2022] [Accepted: 06/17/2022] [Indexed: 11/12/2022]
Abstract
γδ T cells are widely distributed throughout mucosal and epithelial cell-rich tissues and are an important early source of IL-17 in response to several pathogens. Like αβ T cells, γδ T cells undergo a stepwise process of development in the thymus that requires recombination of genome-encoded segments to assemble mature T cell receptor (TCR) genes. This process is tightly controlled on multiple levels to enable TCR segment assembly while preventing the genomic instability inherent in the double-stranded DNA breaks that occur during this process. Each TCR locus has unique aspects in its structure and requirements, with different types of regulation before and after the αβ/γδ T cell fate choice. It has been known that Runx and Myb are critical transcriptional regulators of TCRγ and TCRδ expression, but the roles of E proteins in TCRγ and TCRδ regulation have been less well explored. Multiple lines of evidence show that E proteins are involved in TCR expression at many different levels, including the regulation of Rag recombinase gene expression and protein stability, induction of germline V segment expression, chromatin remodeling, and restriction of the fetal and adult γδTCR repertoires. Importantly, E proteins interact directly with the cis-regulatory elements of the TCRγ and TCRδ loci, controlling the predisposition of a cell to become an αβ T cell or a γδ T cell, even before the lineage-dictating TCR signaling events. This article is categorized under: Immune System Diseases > Stem Cells and Development Immune System Diseases > Genetics/Genomics/Epigenetics.
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Affiliation(s)
- Michele K Anderson
- Department Immunology, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada
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8
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Rodríguez-Caparrós A, Tani-ichi S, Casal Á, López-Ros J, Suñé C, Ikuta K, Hernández-Munain C. Interleukin-7 receptor signaling is crucial for enhancer-dependent TCRδ germline transcription mediated through STAT5 recruitment. Front Immunol 2022; 13:943510. [PMID: 36059467 PMCID: PMC9437428 DOI: 10.3389/fimmu.2022.943510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/03/2022] [Indexed: 11/29/2022] Open
Abstract
γδ T cells play important roles in immune responses by rapidly producing large quantities of cytokines. Recently, γδ T cells have been found to be involved in tissue homeostatic regulation, playing roles in thermogenesis, bone regeneration and synaptic plasticity. Nonetheless, the mechanisms involved in γδ T-cell development, especially the regulation of TCRδ gene transcription, have not yet been clarified. Previous studies have established that NOTCH1 signaling plays an important role in the Tcrg and Tcrd germline transcriptional regulation induced by enhancer activation, which is mediated through the recruitment of RUNX1 and MYB. In addition, interleukin-7 signaling has been shown to be required for Tcrg germline transcription, VγJγ rearrangement and γδ T-lymphocyte generation as well as for promoting T-cell survival. In this study, we discovered that interleukin-7 is required for the activation of enhancer-dependent Tcrd germline transcription during thymocyte development. These results indicate that the activation of both Tcrg and Tcrd enhancers during γδ T-cell development in the thymus depends on the same NOTCH1- and interleukin-7-mediated signaling pathways. Understanding the regulation of the Tcrd enhancer during thymocyte development might lead to a better understanding of the enhancer-dependent mechanisms involved in the genomic instability and chromosomal translocations that cause leukemia.
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Affiliation(s)
- Alonso Rodríguez-Caparrós
- Institute of Parasitology and Biomedicine “López-Neyra”- Spanish Scientific Research Council (IPBLN-CSIC), Technological Park of Health Sciences (PTS), Granada, Spain
| | - Shizue Tani-ichi
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Áurea Casal
- Institute of Parasitology and Biomedicine “López-Neyra”- Spanish Scientific Research Council (IPBLN-CSIC), Technological Park of Health Sciences (PTS), Granada, Spain
| | - Jennifer López-Ros
- Institute of Parasitology and Biomedicine “López-Neyra”- Spanish Scientific Research Council (IPBLN-CSIC), Technological Park of Health Sciences (PTS), Granada, Spain
| | - Carlos Suñé
- Institute of Parasitology and Biomedicine “López-Neyra”- Spanish Scientific Research Council (IPBLN-CSIC), Technological Park of Health Sciences (PTS), Granada, Spain
| | - Koichi Ikuta
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto, Japan
| | - Cristina Hernández-Munain
- Institute of Parasitology and Biomedicine “López-Neyra”- Spanish Scientific Research Council (IPBLN-CSIC), Technological Park of Health Sciences (PTS), Granada, Spain
- *Correspondence: Cristina Hernández-Munain,
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9
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Okoreeh MK, Kennedy DE, Emmanuel AO, Veselits M, Moshin A, Ladd RH, Erickson S, McLean KC, Madrigal B, Nemazee D, Maienschein-Cline M, Mandal M, Clark MR. Asymmetrical forward and reverse developmental trajectories determine molecular programs of B cell antigen receptor editing. Sci Immunol 2022; 7:eabm1664. [PMID: 35930652 PMCID: PMC9636592 DOI: 10.1126/sciimmunol.abm1664] [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] [Indexed: 11/02/2022]
Abstract
During B lymphopoiesis, B cell progenitors progress through alternating and mutually exclusive stages of clonal expansion and immunoglobulin (Ig) gene rearrangements. Great diversity is generated through the stochastic recombination of Ig gene segments encoding heavy and light chain variable domains. However, this commonly generates autoreactivity. Receptor editing is the predominant tolerance mechanism for self-reactive B cells in the bone marrow (BM). B cell receptor editing rescues autoreactive B cells from negative selection through renewed light chain recombination first at Igκ then Igλ loci. Receptor editing depends on BM microenvironment cues and key transcription factors such as NF-κB, FOXO, and E2A. The specific BM factor required for receptor editing is unknown. Furthermore, how transcription factors coordinate these developmental programs to promote usage of the λ chain remains poorly defined. Therefore, we used two mouse models that recapitulate pathways by which Igλ light chain-positive B cells develop. The first has deleted J kappa (Jκ) genes and hence models Igλ expression resulting from failed Igκ recombination (Igκdel). The second models autoreactivity by ubiquitous expression of a single-chain chimeric anti-Igκ antibody (κ-mac). Here, we demonstrated that autoreactive B cells transit asymmetric forward and reverse developmental trajectories. This imparted a unique epigenetic landscape on small pre-B cells, which opened chromatin to transcription factors essential for Igλ recombination. The consequences of this asymmetric developmental path were both amplified and complemented by CXCR4 signaling. These findings reveal how intrinsic molecular programs integrate with extrinsic signals to drive receptor editing.
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Affiliation(s)
- Michael K. Okoreeh
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
- Growth, Development, Disabilities Training program (GDDTP), Pritzker School of Medicine, University of Chicago, IL, 60637, USA
| | - Domenick E. Kennedy
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
- Present Address: Drug Discovery Science and Technology, Discovery Platform Technologies, Chemical Biology and Emerging Therapeutics, AbbVie, North Chicago, IL, United States
| | - Akinola Olumide Emmanuel
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
| | - Margaret Veselits
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
| | - Azam Moshin
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
| | - Robert H. Ladd
- Cytometry and Antibody Technologies Facility, University of Chicago, Chicago, IL, 60637, USA
| | - Steven Erickson
- Department of Pathology, University of Chicago, Chicago, IL, 60637, USA
| | - Kaitlin C. McLean
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
| | - Brianna Madrigal
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
| | - David Nemazee
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Malay Mandal
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
| | - Marcus R. Clark
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, 60637, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, 60637, USA
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10
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Calcagno G, Ouzren N, Kaminski S, Ghislin S, Frippiat JP. Chronic Hypergravity Induces a Modification of Histone H3 Lysine 27 Trimethylation at TCRβ Locus in Murine Thymocytes. Int J Mol Sci 2022; 23:ijms23137133. [PMID: 35806138 PMCID: PMC9267123 DOI: 10.3390/ijms23137133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/24/2022] [Accepted: 06/25/2022] [Indexed: 11/16/2022] Open
Abstract
Gravity changes are major stressors encountered during spaceflight that affect the immune system. We previously evidenced that hypergravity exposure during gestation affects the TCRβ repertoire of newborn pups. To identify the mechanisms underlying this observation, we studied post-translational histone modifications. We first showed that among the four studied post-translational histone H3 modifications, only lysine 27 trimethylation (H3K27me3) is downregulated in the thymus of mice exposed to 2× g for 21 days. We then asked whether the TCRβ locus chromatin structure is altered by hypergravity exposure. ChIP studies performed on four Vβ segments of the murine double-negative SCIET27 thymic cell line, which corresponds to the last maturation stage before V(D)J recombination, revealed increases in H3K27me3 after 2× g exposure. Finally, we evaluated the implication for the EZH2 methyltransferase in the regulation of the H3K27me3 level at these Vβ segments by treating SCIET27 cells with the GSK126-specific inhibitor. These experiments showed that the downregulation of H3K27me3 contributes to the regulation of the Vβ germline transcript expression that precedes V(D)J recombination. These data show that modifications of H3K27me3 at the TCRβ locus likely contribute to an explanation of why the TCR repertoire is affected by gravity changes and imply, for the first time, EZH2 in the regulation of the TCRβ locus chromatin structure.
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11
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Rodríguez-Caparrós A, Álvarez-Santiago J, López-Castellanos L, Ruiz-Rodríguez C, Valle-Pastor MJ, López-Ros J, Angulo Ú, Andrés-León E, Suñé C, Hernández-Munain C. Differently Regulated Gene-Specific Activity of Enhancers Located at the Boundary of Subtopologically Associated Domains: TCRα Enhancer. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:910-928. [PMID: 35082160 DOI: 10.4049/jimmunol.2000864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 12/05/2021] [Indexed: 11/19/2022]
Abstract
Enhancers activate transcription through long-distance interactions with their cognate promoters within a particular subtopologically associated domain (sub-TAD). The TCRα enhancer (Eα) is located at the sub-TAD boundary between the TCRα and DAD1 genes and regulates transcription toward both sides in an ∼1-Mb region. Analysis of Eα activity in transcribing the unrearranged TCRα gene at the 5'-sub-TAD has defined Eα as inactive in CD4-CD8- thymocytes, active in CD4+CD8+ thymocytes, and strongly downregulated in CD4+ and CD8+ thymocytes and αβ T lymphocytes. Despite its strongly reduced activity, Eα is still required for high TCRα transcription and expression of TCRαβ in mouse and human T lymphocytes, requiring collaboration with distant sequences for such functions. Because VαJα rearrangements in T lymphocytes do not induce novel long-range interactions between Eα and other genomic regions that remain in cis after recombination, strong Eα connectivity with the 3'-sub-TAD might prevent reduced transcription of the rearranged TCRα gene. Our analyses of transcriptional enhancer dependence during T cell development and non-T lineage tissues at the 3'-sub-TAD revealed that Eα can activate the transcription of specific genes, even when it is inactive to transcribe the TCRα gene at the 5'-sub-TAD. Hence distinct requirements for Eα function are necessary at specific genes at both sub-TADs, implying that enhancers do not merely function as chromatin loop anchors that nucleate the formation of factor condensates to increase gene transcription initiated at their cognate promoters. The observed different regulated Eα activity for activating specific genes at its flanking sub-TADs may be a general feature for enhancers located at sub-TAD boundaries.
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Affiliation(s)
- Alonso Rodríguez-Caparrós
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Jesús Álvarez-Santiago
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Laura López-Castellanos
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Candela Ruiz-Rodríguez
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - María Jesús Valle-Pastor
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Jennifer López-Ros
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Úrsula Angulo
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Eduardo Andrés-León
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Carlos Suñé
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
| | - Cristina Hernández-Munain
- Institute of Parasitology and Biomedicine López-Neyra-Spanish National Research Council and Health Science Technology Park, Granada, Spain
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12
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Baizan-Edge A, Stubbs BA, Stubbington MJT, Bolland DJ, Tabbada K, Andrews S, Corcoran AE. IL-7R signaling activates widespread V H and D H gene usage to drive antibody diversity in bone marrow B cells. Cell Rep 2021; 36:109349. [PMID: 34260907 PMCID: PMC8293627 DOI: 10.1016/j.celrep.2021.109349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 04/05/2021] [Accepted: 06/15/2021] [Indexed: 01/09/2023] Open
Abstract
Generation of the primary antibody repertoire requires V(D)J recombination of hundreds of gene segments in the immunoglobulin heavy chain (Igh) locus. The role of interleukin-7 receptor (IL-7R) signaling in Igh recombination has been difficult to partition from its role in B cell survival and proliferation. With a detailed description of the Igh repertoire in murine IL-7Rα-/- bone marrow B cells, we demonstrate that IL-7R signaling profoundly influences VH gene selection during VH-to-DJH recombination. We find skewing toward 3' VH genes during de novo VH-to-DJH recombination more severe than the fetal liver (FL) repertoire and uncover a role for IL-7R signaling in DH-to-JH recombination. Transcriptome and accessibility analyses suggest reduced expression of B lineage transcription factors (TFs) and targets and loss of DH and VH antisense transcription in IL-7Rα-/- B cells. Thus, in addition to its roles in survival and proliferation, IL-7R signaling shapes the Igh repertoire by activating underpinning mechanisms.
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Affiliation(s)
- Amanda Baizan-Edge
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Bryony A Stubbs
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Michael J T Stubbington
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Daniel J Bolland
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Lymphocyte Signaling and Development Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Kristina Tabbada
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Lymphocyte Signaling and Development Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon Andrews
- Bioinformatics Group, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Anne E Corcoran
- Nuclear Dynamics Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK; Lymphocyte Signaling and Development Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK.
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13
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Regulation of T-cell Receptor Gene Expression by Three-Dimensional Locus Conformation and Enhancer Function. Int J Mol Sci 2020; 21:ijms21228478. [PMID: 33187197 PMCID: PMC7696796 DOI: 10.3390/ijms21228478] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 10/29/2020] [Accepted: 11/04/2020] [Indexed: 11/16/2022] Open
Abstract
The adaptive immune response in vertebrates depends on the expression of antigen-specific receptors in lymphocytes. T-cell receptor (TCR) gene expression is exquisitely regulated during thymocyte development to drive the generation of αβ and γδ T lymphocytes. The TCRα, TCRβ, TCRγ, and TCRδ genes exist in two different configurations, unrearranged and rearranged. A correctly rearranged configuration is required for expression of a functional TCR chain. TCRs can take the form of one of three possible heterodimers, pre-TCR, TCRαβ, or TCRγδ which drive thymocyte maturation into αβ or γδ T lymphocytes. To pass from an unrearranged to a rearranged configuration, global and local three dimensional (3D) chromatin changes must occur during thymocyte development to regulate gene segment accessibility for V(D)J recombination. During this process, enhancers play a critical role by modifying the chromatin conformation and triggering noncoding germline transcription that promotes the recruitment of the recombination machinery. The different signaling that thymocytes receive during their development controls enhancer activity. Here, we summarize the dynamics of long-distance interactions established through chromatin regulatory elements that drive transcription and V(D)J recombination and how different signaling pathways are orchestrated to regulate the activity of enhancers to precisely control TCR gene expression during T-cell maturation.
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14
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Nakagawa R, Muroyama R, Saeki C, Oikawa T, Kaise Y, Koike K, Arai J, Nakano M, Matsubara Y, Takano K, Hirata Y, Saruta M, Zeniya M, Kato N. CD4 + T cells from patients with primary biliary cholangitis show T cell activation and differentially expressed T-cell receptor repertoires. Hepatol Res 2019; 49:653-662. [PMID: 30690835 DOI: 10.1111/hepr.13318] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 01/08/2019] [Accepted: 01/22/2019] [Indexed: 02/08/2023]
Abstract
AIM Primary biliary cholangitis (PBC) is an autoimmune liver disease with unknown pathogenesis. In PBC, activation of T-cell receptor (TCR) signaling is associated with inflammatory cytokine production through N-Ras upregulation. Although the CD4+ T cell TCR repertoire could be associated with PBC pathogenesis, it has not been evaluated. Thus, we analyzed the PBC-CD4+ T cell TCR repertoire using next generation sequencing (NGS). METHODS Four PBC patients (one treatment-naïve and three receiving ursodeoxycholic acid) and three healthy individuals were enrolled. NRAS expression in CD4+ T cells was assessed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). N-Ras dynamics in CD4+ T cells were assessed by qRT-PCR and GTP-N-Ras activation assay. The TCR α- (TRA) and β-chain (TRB) repertoires on CD4+ T cells were analyzed by NGS and profiled using hierarchical analysis. Motif analysis was undertaken to elucidate the structure of PBC-specific TCRs. RESULTS NRAS was upregulated in PBC relative to control CD4+ T cells (P < 0.05), and N-Ras enhanced T cell activation in CD4+ T cells. Among 2668 TRAs and 841 TRBs, 20 and 11, respectively, were differentially expressed in PBC compared to that in controls (P < 0.05, fold-change >2). Among them, TRAV29/J22, TRBV6-5/J2-6, and TRBV10-1/J2-1 were expressed in PBC but the expression was negligible in the controls, with more mature and longer forms observed in PBC-CD4+ T cells. CONCLUSIONS N-Ras was upregulated in PBC-CD4+ T cells, and it enhanced TCR activation, indicating that PBC-CD4+ T cells were activated by N-Ras upregulation with differentially expressed TCR repertoires on their surfaces.
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Affiliation(s)
- Ryo Nakagawa
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan.,Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan.,Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chiba, Japan
| | - Ryosuke Muroyama
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Chisato Saeki
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Tsunekazu Oikawa
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Yoshimi Kaise
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Kazuhiko Koike
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Jun Arai
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Masanori Nakano
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Yasuo Matsubara
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Keiko Takano
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Yoshihiro Hirata
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Masayuki Saruta
- Department of Gastroenterology and Hepatology, Jikei University School of Medicine, Tokyo, Japan
| | - Mikio Zeniya
- Sanno Medical Center, International University of Health and Welfare, Tokyo, Japan
| | - Naoya Kato
- Division of Advanced Genome Medicine, Institute of Medical Science, University of Tokyo, Tokyo, Japan.,Department of Gastroenterology, Graduate School of Medicine, Chiba University, Chiba, Japan
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15
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Abstract
The vertebrate immune system is tasked with the challenge of responding to any pathogen the organism might encounter, and retaining memory of that pathogen in case of future infection. Recognition and memory of pathogens are encoded within the adaptive immune system and production of T and B lymphocytes with diverse antigen receptor repertoires. In B lymphocytes, diversity is generated by sequential recombination between Variable (V), Diversity (D) and Joining (J) gene segments in the immunoglobulin heavy chain gene (Igh) and subsequent V-J recombination in immunoglobulin light chain genes (Igκ followed by Igλ). However, the process by which particular V, D and J segments are selected during recombination, and stochasticity is maintained to ensure antibody repertoire diversity, is still unclear. In this review, we focus on Igκ and recent findings regarding the relationships between gene structure, the generation of diversity and allelic choice. Surprisingly, the nuclear environment in which each Igκ allele resides, including transcription factories assembled on the nuclear matrix, plays critical roles in both gene regulation and in shaping the diversity of Vκ genes accessible to recombination. These findings provide a new paradigm for understanding Igκ recombination and Vκ diversity in the context of B lymphopoiesis.
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16
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Chen S, Luperchio TR, Wong X, Doan EB, Byrd AT, Roy Choudhury K, Reddy KL, Krangel MS. A Lamina-Associated Domain Border Governs Nuclear Lamina Interactions, Transcription, and Recombination of the Tcrb Locus. Cell Rep 2018; 25:1729-1740.e6. [PMID: 30428344 PMCID: PMC6287930 DOI: 10.1016/j.celrep.2018.10.052] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 10/02/2018] [Accepted: 10/12/2018] [Indexed: 12/26/2022] Open
Abstract
Tcrb locus V(D)J recombination is regulated by positioning at the nuclear periphery. Here, we used DamID to profile Tcrb locus interactions with the nuclear lamina at high resolution. We identified a lamina-associated domain (LAD) border composed of several CTCF-binding elements that segregates active non-LAD from inactive LAD regions of the locus. Deletion of the LAD border causes an enhancer-dependent spread of histone H3 lysine 27 acetylation from the active recombination center into recombination center-proximal LAD chromatin. This is associated with a disruption to nuclear lamina association, increased chromatin looping to the recombination center, and increased transcription and recombination of recombination center-proximal gene segments. Our results show that a LAD and LAD border are critical components of Tcrb locus gene regulation and suggest that LAD borders may generally function to constrain the activity of nearby enhancers.
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Affiliation(s)
- Shiwei Chen
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Teresa Romeo Luperchio
- Department of Biological Chemistry, Center for Epigenetics, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Xianrong Wong
- Department of Biological Chemistry, Center for Epigenetics, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Europe B Doan
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Aaron T Byrd
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kingshuk Roy Choudhury
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - Karen L Reddy
- Department of Biological Chemistry, Center for Epigenetics, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA.
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17
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Khamlichi AA, Feil R. Parallels between Mammalian Mechanisms of Monoallelic Gene Expression. Trends Genet 2018; 34:954-971. [PMID: 30217559 DOI: 10.1016/j.tig.2018.08.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/06/2018] [Accepted: 08/16/2018] [Indexed: 02/06/2023]
Abstract
Different types of monoallelic gene expression are present in mammals, some of which are highly flexible, whereas others are more rigid. These include allelic exclusion at antigen receptor loci, the expression of olfactory receptor genes, genomic imprinting, X-chromosome inactivation, and random monoallelic expression (MAE). Although these processes play diverse biological roles, and arose through different selective pressures, the underlying epigenetic mechanisms show striking resemblances. Regulatory transcriptional events are important in all systems, particularly in the specification of MAE. Combined with comparative studies between species, this suggests that the different MAE systems found in mammals may have evolved from analogous ancestral processes.
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Affiliation(s)
- Ahmed Amine Khamlichi
- Institute of Pharmacology and Structural Biology (IPBS), Centre National de la Recherche Scientifique (CNRS) and Paul Sabatier University (UPS), 205 route de Narbonne, 31077 Toulouse, France.
| | - Robert Feil
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS and the University of Montpellier, 1919 route de Mende, 34293 Montpellier, France.
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18
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Carico ZM, Roy Choudhury K, Zhang B, Zhuang Y, Krangel MS. Tcrd Rearrangement Redirects a Processive Tcra Recombination Program to Expand the Tcra Repertoire. Cell Rep 2018; 19:2157-2173. [PMID: 28591585 DOI: 10.1016/j.celrep.2017.05.045] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 04/21/2017] [Accepted: 05/13/2017] [Indexed: 01/01/2023] Open
Abstract
Adaptive immunity depends on diverse T cell receptor repertoires generated by variable, diversity, and joining (V[D]J) recombination. Here, we define the principles by which combinatorial diversity is generated in the murine Tcra repertoire. Tcra and Tcrd gene segments share the Tcra-Tcrd locus, with interspersed Vα and Vδ segments undergoing Vδ-Dδ-Jδ rearrangement in CD4-CD8- thymocytes and then multiple rounds of Vα-Jα rearrangement in CD4+CD8+ thymocytes. We document stepwise, highly coordinated proximal-to-distal progressions of Vα and Jα use on individual Tcra alleles, limiting combinatorial diversity. This behavior is supported by an extended chromatin conformation in CD4+CD8+ thymocytes, with only nearby Vα and Jα segments contacting each other. Tcrd rearrangements can use distal Vδ segments due to a contracted Tcra-Tcrd conformation in CD4-CD8- thymocytes. These rearrangements expand the Tcra repertoire by truncating the Vα array to permit otherwise disfavored Vα-Jα combinations. Therefore, recombination events at two developmental stages with distinct chromatin conformations synergize to promote Tcra repertoire diversity.
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Affiliation(s)
- Zachary M Carico
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Kingshuk Roy Choudhury
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27710, USA
| | - Baojun Zhang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Yuan Zhuang
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA.
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19
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Outters P, Jaeger S, Zaarour N, Ferrier P. Long-Range Control of V(D)J Recombination & Allelic Exclusion: Modeling Views. Adv Immunol 2015; 128:363-413. [PMID: 26477371 DOI: 10.1016/bs.ai.2015.08.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Allelic exclusion of immunoglobulin (Ig) and T-cell receptor (TCR) genes ensures the development of B and T lymphocytes operating under the mode of clonal selection. This phenomenon associates asynchronous V(D)J recombination events at Ig or TCR alleles and inhibitory feedback control. Despite years of intense research, however, the mechanisms that sustain asymmetric choice in random Ig/TCR dual allele usage and the production of Ig/TCR monoallelic expressing B and T lymphocytes remain unclear and open for debate. In this chapter, we first recapitulate the biological evidence that almost from the start appeared to link V(D)J recombination and allelic exclusion. We review the theoretical models previously proposed to explain this connection. Finally, we introduce our own mathematical modeling views based on how the developmental dynamics of individual lymphoid cells combine to sustain allelic exclusion.
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Affiliation(s)
- Pernelle Outters
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Sébastien Jaeger
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Nancy Zaarour
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Pierre Ferrier
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France.
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20
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Histone reader BRWD1 targets and restricts recombination to the Igk locus. Nat Immunol 2015; 16:1094-103. [PMID: 26301565 PMCID: PMC4575638 DOI: 10.1038/ni.3249] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 07/15/2015] [Indexed: 12/12/2022]
Abstract
B lymphopoiesis requires that immunoglobulin genes be accessible to the RAG1-RAG2 recombinase. However, the RAG proteins bind widely to open chromatin suggesting that additional mechanisms must restrict RAG-mediated DNA cleavage. Here, we demonstrate developmental downregulation of interleukin 7 (IL-7) receptor signaling in small pre-B cells induced expression of the bromodomain family member BRWD1, which was recruited to a specific epigenetic landscape at Igk dictated by pre-BCR-dependent Erk activation. BRWD1 enhanced RAG recruitment, increased gene accessibility and positioned nucleosomes 5′ to each Jκ recombination signal sequence. BRWD1 thus targets recombination to Igk and places recombination within the context of signaling cascades that control B cell development. Our findings provide a paradigm in which, at any particular antigen receptor locus, specialized mechanisms enforce lineage and stage specific recombination.
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21
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Proudhon C, Hao B, Raviram R, Chaumeil J, Skok JA. Long-Range Regulation of V(D)J Recombination. Adv Immunol 2015; 128:123-82. [PMID: 26477367 DOI: 10.1016/bs.ai.2015.07.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Given their essential role in adaptive immunity, antigen receptor loci have been the focus of analysis for many years and are among a handful of the most well-studied genes in the genome. Their investigation led initially to a detailed knowledge of linear structure and characterization of regulatory elements that confer control of their rearrangement and expression. However, advances in DNA FISH and imaging combined with new molecular approaches that interrogate chromosome conformation have led to a growing appreciation that linear structure is only one aspect of gene regulation and in more recent years, the focus has switched to analyzing the impact of locus conformation and nuclear organization on control of recombination. Despite decades of work and intense effort from numerous labs, we are still left with an incomplete picture of how the assembly of antigen receptor loci is regulated. This chapter summarizes our advances to date and points to areas that need further investigation.
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Affiliation(s)
- Charlotte Proudhon
- Department of Pathology, New York University School of Medicine, New York, USA
| | - Bingtao Hao
- Department of Pathology, New York University School of Medicine, New York, USA
| | - Ramya Raviram
- Department of Pathology, New York University School of Medicine, New York, USA
| | - Julie Chaumeil
- Institut Curie, CNRS UMR3215, INSERM U934, Paris, France
| | - Jane A Skok
- Department of Pathology, New York University School of Medicine, New York, USA.
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22
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Majumder K, Bassing CH, Oltz EM. Regulation of Tcrb Gene Assembly by Genetic, Epigenetic, and Topological Mechanisms. Adv Immunol 2015; 128:273-306. [PMID: 26477369 DOI: 10.1016/bs.ai.2015.07.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The adaptive immune system endows mammals with an ability to recognize nearly any foreign invader through antigen receptors that are expressed on the surface of all lymphocytes. This defense network is generated by V(D)J recombination, a set of sequentially controlled DNA cleavage and repair events that assemble antigen receptor genes from physically separated variable (V), joining (J), and sometimes diversity (D) gene segments. The recombination process itself must be stringently regulated to minimize oncogenic translocations involving chromosomes that harbor immunoglobulin and T cell receptor loci. Indeed, V(D)J recombination is controlled at several levels, including tissue-, developmental stage-, allele-, and gene segment-specificity. These levels of control are imposed by a collection of architectural and regulatory elements that are distributed throughout each antigen receptor locus. Together, the genetic elements regulate developmental changes in chromatin, transcription, and locus topology that promote or disfavor long-range recombination. This chapter focuses on the cross talk between these mechanisms at the T cell receptor beta (Tcrb) locus, and how they sculpt a diverse TCRβ repertoire while maintaining monospecificity of this antigen receptor on each mature T lymphocyte. We also discuss how insights obtained from studies of Tcrb are more generally relevant to our understanding of gene regulation strategies employed by mammals.
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Affiliation(s)
- Kinjal Majumder
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Craig H Bassing
- Division of Cancer Pathobiology, Department of Pathology and Laboratory Medicine, Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA; Abramson Family Cancer Research Institute, Cell and Molecular Biology Graduate Program, Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Eugene M Oltz
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA.
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Influence of a CTCF-Dependent Insulator on Multiple Aspects of Enhancer-Mediated Chromatin Organization. Mol Cell Biol 2015; 35:3504-16. [PMID: 26240285 DOI: 10.1128/mcb.00514-15] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 07/24/2015] [Indexed: 01/07/2023] Open
Abstract
Developmental stage-specific enhancer-promoter-insulator interactions regulate the chromatin configuration necessary for transcription at various loci and additionally for VDJ recombination at antigen receptor loci that encode immunoglobulins and T-cell receptors. To investigate these regulatory interactions, we analyzed the epigenetic landscape of the murine T-cell receptor β (TCRβ) locus in the presence and absence of an ectopic CTCF-dependent enhancer-blocking insulator, H19-ICR, in genetically manipulated mice. Our analysis demonstrated the ability of the H19-ICR insulator to restrict several aspects of enhancer-based chromatin alterations that are observed during activation of the TCRβ locus for transcription and recombination. The H19-ICR insulator abrogated enhancer-promoter contact-dependent chromatin alterations and additionally prevented Eβ-mediated histone modifications that have been suggested to be independent of enhancer-promoter interaction. Observed enhancer-promoter-insulator interactions, in conjunction with the chromatin structure of the Eβ-regulated domain at the nucleosomal level, provide useful insights regarding the activity of the regulatory elements in addition to supporting the accessibility hypothesis of VDJ recombination. Analysis of H19-ICR in the heterologous context of the developmentally regulated TCRβ locus suggests that different mechanisms proposed for CTCF-dependent insulator action might be manifested simultaneously or selectively depending on the genomic context and the nature of enhancer activity being curtailed.
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Hernández-Munain C. Recent insights into the transcriptional control of the Tcra/Tcrd locus by distant enhancers during the development of T-lymphocytes. Transcription 2015; 6:65-73. [PMID: 26230488 DOI: 10.1080/21541264.2015.1078429] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Tcra/Tcrd includes 2 genes with distinct developmental programs controlled by 2 distant enhancers, Eα and Eδ. These enhancers work as a developmental switch during thymocyte development and they are essential for generation of αβ and γδ T-lymphocytes. Tcra and Tcrd transit from an unrearranged configuration to a rearranged configuration during T-cell development. Eα and Eδ are responsible for transcription of their respective unrearranged genes in thymocytes but are dispensable for such functions in the context of the rearranged genes in mature T-cells. Interestingly, Eα activates transcription of the rearranged Tcrd in γδ T-lymphocytes but it is inactive in αβ T-lymphocytes.
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Affiliation(s)
- Cristina Hernández-Munain
- a Department of Cellular Biology and Immunology ; Instituto de Parasitología y Biomedicina López-Neyra (IPBLN-CSIC); Parque Tecnológico de Ciencias de la Salud (PTS) ; Armilla , Granada , Spain
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25
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Wagatsuma K, Tani-ichi S, Liang B, Shitara S, Ishihara K, Abe M, Miyachi H, Kitano S, Hara T, Nanno M, Ishikawa H, Sakimura K, Nakao M, Kimura H, Ikuta K. STAT5 Orchestrates Local Epigenetic Changes for Chromatin Accessibility and Rearrangements by Direct Binding to the TCRγ Locus. THE JOURNAL OF IMMUNOLOGY 2015. [PMID: 26195811 DOI: 10.4049/jimmunol.1302456] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The transcription factor STAT5, which is activated by IL-7R, controls chromatin accessibility and rearrangements of the TCRγ locus. Although STAT-binding motifs are conserved in Jγ promoters and Eγ enhancers, little is known about their precise roles in rearrangements of the TCRγ locus in vivo. To address this question, we established two lines of Jγ1 promoter mutant mice: one harboring a deletion in the Jγ1 promoter, including three STAT motifs (Jγ1P(Δ/Δ)), and the other carrying point mutations in the three STAT motifs in that promoter (Jγ1P(mS/mS)). Both Jγ1P(Δ/Δ) and Jγ1P(mS/mS) mice showed impaired recruitment of STAT5 and chromatin remodeling factor BRG1 at the Jγ1 gene segment. This resulted in severe and specific reduction in germline transcription, histone H3 acetylation, and histone H4 lysine 4 methylation of the Jγ1 gene segment in adult thymus. Rearrangement and DNA cleavage of the segment were severely diminished, and Jγ1 promoter mutant mice showed profoundly decreased numbers of γδ T cells of γ1 cluster origin. Finally, compared with controls, both mutant mice showed a severe reduction in rearrangements of the Jγ1 gene segment, perturbed development of γδ T cells of γ1 cluster origin in fetal thymus, and fewer Vγ3(+) dendritic epidermal T cells. Furthermore, interaction with the Jγ1 promoter and Eγ1, a TCRγ enhancer, was dependent on STAT motifs in the Jγ1 promoter. Overall, this study strongly suggests that direct binding of STAT5 to STAT motifs in the Jγ promoter is essential for local chromatin accessibility and Jγ/Eγ chromatin interaction, triggering rearrangements of the TCRγ locus.
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Affiliation(s)
- Keisuke Wagatsuma
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan; Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Shizue Tani-ichi
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
| | - Bingfei Liang
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan; Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Soichiro Shitara
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan; Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Ko Ishihara
- Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-0811, Japan
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Hitoshi Miyachi
- Reproductive Engineering Team, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
| | - Satsuki Kitano
- Reproductive Engineering Team, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
| | - Takahiro Hara
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan
| | - Masanobu Nanno
- Yakult Central Institute, Kunitachi, Tokyo 186-8650, Japan
| | | | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Mitsuyoshi Nakao
- Department of Medical Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 860-0811, Japan; Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Hiroshi Kimura
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan; Graduate School of Frontier Bioscience, Osaka University, Suita 565-0871, Japan; and Department of Biological Sciences, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan
| | - Koichi Ikuta
- Laboratory of Biological Protection, Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan;
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26
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Panzeri I, Rossetti G, Abrignani S, Pagani M. Long Intergenic Non-Coding RNAs: Novel Drivers of Human Lymphocyte Differentiation. Front Immunol 2015; 6:175. [PMID: 25926836 PMCID: PMC4397839 DOI: 10.3389/fimmu.2015.00175] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 03/28/2015] [Indexed: 12/29/2022] Open
Abstract
Upon recognition of a foreign antigen, CD4(+) naïve T lymphocytes proliferate and differentiate into subsets with distinct functions. This process is fundamental for the effective immune system function, as CD4(+) T cells orchestrate both the innate and adaptive immune response. Traditionally, this differentiation event has been regarded as the acquisition of an irreversible cell fate so that memory and effector CD4(+) T subsets were considered terminally differentiated cells or lineages. Consequently, these lineages are conventionally defined thanks to their prototypical set of cytokines and transcription factors. However, recent findings suggest that CD4(+) T lymphocytes possess a remarkable phenotypic plasticity, as they can often re-direct their functional program depending on the milieu they encounter. Therefore, new questions are now compelling such as which are the molecular determinants underlying plasticity and stability and how the balance between these two opposite forces drives the cell fate. As already mentioned, in some cases, the mere expression of cytokines and master regulators could not fully explain lymphocytes plasticity. We should consider other layers of regulation, including epigenetic factors such as the modulation of chromatin state or the transcription of non-coding RNAs, whose high cell-specificity give a hint on their involvement in cell fate determination. In this review, we will focus on the recent advances in understanding CD4(+) T lymphocytes subsets specification from an epigenetic point of view. In particular, we will emphasize the emerging importance of non-coding RNAs as key players in these differentiation events. We will also present here new data from our laboratory highlighting the contribution of long non-coding RNAs in driving human CD4(+) T lymphocytes differentiation.
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Affiliation(s)
- Ilaria Panzeri
- Integrative Biology Unit, Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", IRCCS Ospedale Maggiore Policlinico , Milano , Italy
| | - Grazisa Rossetti
- Integrative Biology Unit, Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", IRCCS Ospedale Maggiore Policlinico , Milano , Italy
| | - Sergio Abrignani
- Integrative Biology Unit, Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", IRCCS Ospedale Maggiore Policlinico , Milano , Italy
| | - Massimiliano Pagani
- Integrative Biology Unit, Istituto Nazionale Genetica Molecolare "Romeo ed Enrica Invernizzi", IRCCS Ospedale Maggiore Policlinico , Milano , Italy ; Department of Medical Biotechnology and Translational Medicine, Università degli Studi di Milano , Milano , Italy
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27
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Abstract
The Tcra enhancer (Eα) is essential for Tcra locus germ-line transcription and primary Vα-to-Jα recombination during thymocyte development. We found that Eα is inhibited late during thymocyte differentiation and in αβ T lymphocytes, indicating that it is not required to drive transcription of rearranged Tcra genes. Eα inactivation resulted in the disruption of functional long-range enhancer-promoter interactions and was associated with loss of Eα-dependent histone modifications at promoter and enhancer regions, and reduced expression and recruitment of E2A to the Eα enhanceosome in T cells. Enhancer activity could not be recovered by T-cell activation, by forced expression of E2A or by the up-regulation of this and other transcription factors in the context of T helper differentiation. Our results argue that the major function of Eα is to coordinate the formation of a chromatin hub that drives Vα and Jα germ-line transcription and primary rearrangements in thymocytes and imply the existence of an Eα-independent mechanism to activate transcription of the rearranged Tcra locus in αβ T cells.
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28
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Zacarías-Cabeza J, Belhocine M, Vanhille L, Cauchy P, Koch F, Pekowska A, Fenouil R, Bergon A, Gut M, Gut I, Eick D, Imbert J, Ferrier P, Andrau JC, Spicuglia S. Transcription-dependent generation of a specialized chromatin structure at the TCRβ locus. THE JOURNAL OF IMMUNOLOGY 2015; 194:3432-43. [PMID: 25732733 DOI: 10.4049/jimmunol.1400789] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
V(D)J recombination assembles Ag receptor genes during lymphocyte development. Enhancers at AR loci are known to control V(D)J recombination at associated alleles, in part by increasing chromatin accessibility of the locus, to allow the recombination machinery to gain access to its chromosomal substrates. However, whether there is a specific mechanism to induce chromatin accessibility at AR loci is still unclear. In this article, we highlight a specialized epigenetic marking characterized by high and extended H3K4me3 levels throughout the Dβ-Jβ-Cβ gene segments. We show that extended H3K4 trimethylation at the Tcrb locus depends on RNA polymerase II (Pol II)-mediated transcription. Furthermore, we found that the genomic regions encompassing the two DJCβ clusters are highly enriched for Ser(5)-phosphorylated Pol II and short-RNA transcripts, two hallmarks of transcription initiation and early transcription. Of interest, these features are shared with few other tissue-specific genes. We propose that the entire DJCβ regions behave as transcription "initiation" platforms, therefore linking a specialized mechanism of Pol II transcription with extended H3K4 trimethylation and highly accessible Dβ and Jβ gene segments.
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Affiliation(s)
- Joaquin Zacarías-Cabeza
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France
| | - Mohamed Belhocine
- INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France
| | - Laurent Vanhille
- INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France
| | - Pierre Cauchy
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France; INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France
| | - Frederic Koch
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France
| | - Aleksandra Pekowska
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France
| | - Romain Fenouil
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France
| | - Aurélie Bergon
- INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Transcriptomic and Genomic Marseille-Luminy, Infrastructures en Biologie, Santé et Agronomie, 13288 Marseille, France
| | - Marta Gut
- Centre Nacional D'Anàlisi Genòmica, Parc Científic de Barcelona, Baldiri i Reixac, 08028 Barcelona, Spain
| | - Ivo Gut
- Centre Nacional D'Anàlisi Genòmica, Parc Científic de Barcelona, Baldiri i Reixac, 08028 Barcelona, Spain
| | - Dirk Eick
- Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science, 80336 Munich, Germany; and
| | - Jean Imbert
- INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Transcriptomic and Genomic Marseille-Luminy, Infrastructures en Biologie, Santé et Agronomie, 13288 Marseille, France
| | - Pierre Ferrier
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France;
| | - Jean-Christophe Andrau
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France; Institut de Génétique Moléculaire de Montpellier, Centre National de la Recherche Scientifique, UMR5535, 34293 Montpellier, France
| | - Salvatore Spicuglia
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, UM2, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; Centre National de la Recherche Scientifique, UMR7280, F-13009 Marseille, France; INSERM U1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France; Aix-Marseille University, UMR-S 1090, Technological Advances for Genomics and Clinics, F-13009 Marseille, France;
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29
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Boudil A, Matei IR, Shih HY, Bogdanoski G, Yuan JS, Chang SG, Montpellier B, Kowalski PE, Voisin V, Bashir S, Bader GD, Krangel MS, Guidos CJ. IL-7 coordinates proliferation, differentiation and Tcra recombination during thymocyte β-selection. Nat Immunol 2015; 16:397-405. [PMID: 25729925 PMCID: PMC4368453 DOI: 10.1038/ni.3122] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/10/2015] [Indexed: 12/15/2022]
Abstract
Signaling via the pre-T cell antigen receptor (pre-TCR) and the receptor Notch1 induces transient self-renewal (β-selection) of TCRβ(+) CD4(-)CD8(-) double-negative stage 3 (DN3) and DN4 progenitor cells that differentiate into CD4(+)CD8(+) double-positive (DP) thymocytes, which then rearrange the locus encoding the TCR α-chain (Tcra). Interleukin 7 (IL-7) promotes the survival of TCRβ(-) DN thymocytes by inducing expression of the pro-survival molecule Bcl-2, but the functions of IL-7 during β-selection have remained unclear. Here we found that IL-7 signaled TCRβ(+) DN3 and DN4 thymocytes to upregulate genes encoding molecules involved in cell growth and repressed the gene encoding the transcriptional repressor Bcl-6. Accordingly, IL-7-deficient DN4 cells lacked trophic receptors and did not proliferate but rearranged Tcra prematurely and differentiated rapidly. Deletion of Bcl6 partially restored the self-renewal of DN4 cells in the absence of IL-7, but overexpression of BCL2 did not. Thus, IL-7 critically acts cooperatively with signaling via the pre-TCR and Notch1 to coordinate proliferation, differentiation and Tcra recombination during β-selection.
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Affiliation(s)
- Amine Boudil
- 1] Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada. [2] Department of Immunology, University of Toronto, Toronto, Canada
| | - Irina R Matei
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada
| | - Han-Yu Shih
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Goce Bogdanoski
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada
| | - Julie S Yuan
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada
| | - Stephen G Chang
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada
| | - Bertrand Montpellier
- 1] Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada. [2] Department of Immunology, University of Toronto, Toronto, Canada
| | - Paul E Kowalski
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada
| | | | | | - Gary D Bader
- 1] The Donnelly Centre, University of Toronto, Toronto, Canada. [2] Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA
| | - Cynthia J Guidos
- 1] Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Canada. [2] Department of Immunology, University of Toronto, Toronto, Canada
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30
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The proximal J kappa germline-transcript promoter facilitates receptor editing through control of ordered recombination. PLoS One 2015; 10:e0113824. [PMID: 25559567 PMCID: PMC4283955 DOI: 10.1371/journal.pone.0113824] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Accepted: 10/31/2014] [Indexed: 12/31/2022] Open
Abstract
V(D)J recombination creates antibody light chain diversity by joining a Vκ gene segment with one of four Jκ segments. Two Jκ germline-transcript (GT) promoters control Vκ-Jκ joining, but the mechanisms that govern Jκ choice are unclear. Here, we show in gene-targeted mice that the proximal GT promoter helps targeting rearrangements to Jκ1 by preventing premature DNA breaks at Jκ2. Consequently, cells lacking the proximal GT promoter show a biased utilization of downstream Jκ segments, resulting in a diminished potential for receptor editing. Surprisingly, the proximal—in contrast to the distal—GT promoter is transcriptionally inactive prior to Igκ recombination, indicating that its role in Jκ choice is independent of classical promoter function. Removal of the proximal GT promoter increases H3K4me3 levels at Jκ segments, suggesting that this promoter could act as a suppressor of recombination by limiting chromatin accessibility to RAG. Our findings identify the first cis-element critical for Jκ choice and demonstrate that ordered Igκ recombination facilitates receptor editing.
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31
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Carico Z, Krangel MS. Chromatin Dynamics and the Development of the TCRα and TCRδ Repertoires. Adv Immunol 2015; 128:307-61. [DOI: 10.1016/bs.ai.2015.07.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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32
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de Almeida CR, Hendriks RW, Stadhouders R. Dynamic Control of Long-Range Genomic Interactions at the Immunoglobulin κ Light-Chain Locus. Adv Immunol 2015; 128:183-271. [DOI: 10.1016/bs.ai.2015.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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33
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Ikaros and RAG-2-mediated antisense transcription are responsible for lymphocyte-specific inactivation of NWC promoter. PLoS One 2014; 9:e106927. [PMID: 25198102 PMCID: PMC4157847 DOI: 10.1371/journal.pone.0106927] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 08/03/2014] [Indexed: 02/03/2023] Open
Abstract
Recombination activating gene-2 (RAG-2) and NWC are strongly evolutionarily conserved overlapping genes which are convergently transcribed. In non-lymphoid cells the NWC promoter is active whereas in lymphocytes it is inactive due to the DNA methylation. Analysing the mechanism responsible for lymphocyte-specific methylation and inactivation of NWC promoter we found that Ikaros, a lymphocyte-specific transcription factor, acts as a repressor of NWC promoter - thus identifying a new Ikaros target - but is insufficient for inducing its methylation which depends on the antisense transcription driven by RAG-2 promoter. Possible implications of these observations for understanding evolutionary mechanisms leading to lymphocyte specific expression of RAG genes are discussed.
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34
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Bonelli M, Shih HY, Hirahara K, Singelton K, Laurence A, Poholek A, Hand T, Mikami Y, Vahedi G, Kanno Y, O'Shea JJ. Helper T cell plasticity: impact of extrinsic and intrinsic signals on transcriptomes and epigenomes. Curr Top Microbiol Immunol 2014; 381:279-326. [PMID: 24831346 DOI: 10.1007/82_2014_371] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CD4(+) helper T cells are crucial for autoimmune and infectious diseases; however, the recognition of the many, diverse fates available continues unabated. Precisely what controls specification of helper T cells and preserves phenotypic commitment is currently intensively investigated. In this review, we will discuss the major factors that impact helper T cell fate choice, ranging from cytokines and the microbiome to metabolic control and epigenetic regulation. We will also discuss the technological advances along with the attendant challenges presented by "big data," which allow the understanding of these processes on comprehensive scales.
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Affiliation(s)
- Michael Bonelli
- Molecular Immunology and Inflammation Branch, National Institutes of Arthritis, and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD, USA
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35
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Daley SR, Coakley KM, Hu DY, Randall KL, Jenne CN, Limnander A, Myers DR, Polakos NK, Enders A, Roots C, Balakishnan B, Miosge LA, Sjollema G, Bertram EM, Field MA, Shao Y, Andrews TD, Whittle B, Barnes SW, Walker JR, Cyster JG, Goodnow CC, Roose JP. Rasgrp1 mutation increases naive T-cell CD44 expression and drives mTOR-dependent accumulation of Helios⁺ T cells and autoantibodies. eLife 2013; 2:e01020. [PMID: 24336796 PMCID: PMC3858598 DOI: 10.7554/elife.01020] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Missense variants are a major source of human genetic variation. Here we analyze a new mouse missense variant, Rasgrp1Anaef, with an ENU-mutated EF hand in the Rasgrp1 Ras guanine nucleotide exchange factor. Rasgrp1Anaef mice exhibit anti-nuclear autoantibodies and gradually accumulate a CD44hi Helios+ PD-1+ CD4+ T cell population that is dependent on B cells. Despite reduced Rasgrp1-Ras-ERK activation in vitro, thymocyte selection in Rasgrp1Anaef is mostly normal in vivo, although CD44 is overexpressed on naïve thymocytes and T cells in a T-cell-autonomous manner. We identify CD44 expression as a sensitive reporter of tonic mTOR-S6 kinase signaling through a novel mouse strain, chino, with a reduction-of-function mutation in Mtor. Elevated tonic mTOR-S6 signaling occurs in Rasgrp1Anaef naïve CD4+ T cells. CD44 expression, CD4+ T cell subset ratios and serum autoantibodies all returned to normal in Rasgrp1AnaefMtorchino double-mutant mice, demonstrating that increased mTOR activity is essential for the Rasgrp1Anaef T cell dysregulation. DOI:http://dx.doi.org/10.7554/eLife.01020.001 Our DNA contains more than three billion nucleotides. Each of these nucleotides can be an A, C, G or T, and groups of three neighboring nucleotides within our DNA are used to represent the 20 amino acids that are used to make proteins. This means that changing just one nucleotide can cause one amino acid to be replaced by a different amino acid in the protein encoded by that stretch of DNA: AAA and AAG code for the amino acid lysine, for example, but AAC and AAT code for asparagine. Known as missense gene variants, these changes can also increase or decrease the expression of the gene. Every person has thousands of missense gene variants, including about 12,000 inherited from their parents. Sometimes these variants have no consequence, but they can be harmful if replacing the correct amino acid with a different amino acid prevents the protein from performing an important task. In particular, missense gene variants in genes that encode immune system proteins are likely to play a role in diseases of the immune system. For example, variants near a gene called Rasgrp1 have been linked to two autoimmune diseases – type 1 diabetes and Graves’ disease—in which the immune system mistakenly attacks the body’s own cells and tissues. Now Daley et al. have shed new light on the mechanism by which a missense gene variant in Rasgrp1 can cause autoimmune diseases. Mice with this mutation show signs of autoimmune disease, but their T cells—white blood cells that have a central role in the immune system – develop normally despite this mutation. Instead, Daley et al. found that a specific type of T cell, called T helper cells, accumulated in large numbers in the mutant mice and stimulated cells of a third type—immune cells called B cells—to produce autoantibodies. The production of autoantibodies is a common feature of autoimmune diseases. Daley et al. traced the origins of the T helper cells to excessive activity on a signaling pathway that involves a protein called mTOR, and went on to show that treatment with the drug rapamycin counteracted the accumulation of the T helper cells and reduced the level of autoimmune activity. In addition to exemplifying how changing just one amino acid change can have a profound effect, the work of Daley et al. is an attractive model for exploring how missense gene variants in people can contribute to autoimmune diseases. DOI:http://dx.doi.org/10.7554/eLife.01020.002
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Affiliation(s)
- Stephen R Daley
- Department of Immunology, John Curtin School of Medical Research, The Australian National University, Canberra, Australia
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RNA in unexpected places: long non-coding RNA functions in diverse cellular contexts. Nat Rev Mol Cell Biol 2013; 14:699-712. [PMID: 24105322 DOI: 10.1038/nrm3679] [Citation(s) in RCA: 1106] [Impact Index Per Article: 100.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The increased application of transcriptome-wide profiling approaches has led to an explosion in the number of documented long non-coding RNAs (lncRNAs). While these new and enigmatic players in the complex transcriptional milieu are encoded by a significant proportion of the genome, their functions are mostly unknown. Early discoveries support a paradigm in which lncRNAs regulate transcription via chromatin modulation, but new functions are steadily emerging. Given the biochemical versatility of RNA, lncRNAs may be used for various tasks, including post-transcriptional regulation, organization of protein complexes, cell-cell signalling and allosteric regulation of proteins.
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Jaeger S, Fernandez B, Ferrier P. Epigenetic aspects of lymphocyte antigen receptor gene rearrangement or 'when stochasticity completes randomness'. Immunology 2013; 139:141-50. [PMID: 23278765 DOI: 10.1111/imm.12057] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 12/17/2012] [Accepted: 12/19/2012] [Indexed: 01/05/2023] Open
Abstract
To perform their specific functional role, B and T lymphocytes, cells of the adaptive immune system of jawed vertebrates, need to express one (and, preferably, only one) form of antigen receptor, i.e. the immunoglobulin or T-cell receptor (TCR), respectively. This end goal depends initially on a series of DNA cis-rearrangement events between randomly chosen units from separate clusters of V, D (at some immunoglobulin and TCR loci) and J gene segments, a biomolecular process collectively referred to as V(D)J recombination. V(D)J recombination takes place in immature T and B cells and relies on the so-called RAG nuclease, a site-specific DNA cleavage apparatus that corresponds to the lymphoid-specific moiety of the VDJ recombinase. At the genome level, this recombinase's mission presents substantial biochemical challenges. These relate to the huge distance between (some of) the gene segments that it eventually rearranges and the need to achieve cell-lineage-restricted and developmentally ordered routines with at times, mono-allelic versus bi-allelic discrimination. The entire process must be completed without any recombination errors, instigators of chromosome instability, translocation and, potentially, tumorigenesis. As expected, such a precisely choreographed and yet potentially risky process demands sophisticated controls; epigenetics demonstrates what is possible when calling upon its many facets. In this vignette, we will recall the evidence that almost from the start appeared to link the two topics, V(D)J recombination and epigenetics, before reviewing the latest advances in our knowledge of this joint venture.
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Affiliation(s)
- Sébastien Jaeger
- Centre d'Immunologie de Marseille-Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (Inserm) U1104, Centre National de la Recherche Scientifique (CNRS)UMR7280, Aix-Marseille University UM2, Marseille, France
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Gopalakrishnan S, Collins PL, Oltz EM. Control of Ig gene assembly: lessons from premature activation. EMBO J 2013; 32:1350-1. [PMID: 23612612 DOI: 10.1038/emboj.2013.94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Suhasni Gopalakrishnan
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, MO, USA
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Bevington S, Boyes J. Transcription-coupled eviction of histones H2A/H2B governs V(D)J recombination. EMBO J 2013; 32:1381-92. [PMID: 23463099 PMCID: PMC3655464 DOI: 10.1038/emboj.2013.42] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 02/05/2013] [Indexed: 12/23/2022] Open
Abstract
Initiation of V(D)J recombination critically relies on the formation of an accessible chromatin structure at recombination signal sequences (RSSs) but how this accessibility is generated is poorly understood. Immunoglobulin light-chain loci normally undergo recombination in pre-B cells. We show here that equipping (earlier) pro-B cells with the increased pre-B-cell levels of just one transcription factor, IRF4, triggers the entire cascade of events leading to premature light-chain recombination. We then used this finding to dissect the critical events that generate RSS accessibility and show that the chromatin modifications previously associated with recombination are insufficient. Instead, we establish that non-coding transcription triggers IgL RSS accessibility and find that the accessibility is transient. Transcription transiently evicts H2A/H2B dimers, releasing 35-40 bp of nucleosomal DNA, and we demonstrate that H2A/H2B loss can explain the RSS accessibility observed in vivo. We therefore propose that the transcription-mediated eviction of H2A/H2B dimers is an important mechanism that makes RSSs accessible for the initiation of recombination.
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Affiliation(s)
- Sarah Bevington
- Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Joan Boyes
- Institute of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
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Stubbington MJT, Corcoran AE. Non-coding transcription and large-scale nuclear organisation of immunoglobulin recombination. Curr Opin Genet Dev 2013; 23:81-8. [PMID: 23434028 DOI: 10.1016/j.gde.2013.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 01/07/2013] [Indexed: 02/01/2023]
Abstract
The enormous antigen receptor loci in lymphocytes are a paradigm of dynamic nuclear organisation, which is integral to their need to move extensively in 3D space to achieve distal gene synapse for V(D)J recombination and allelic exclusion. The loci undergo extensive 3D looping to bring distal genes together, controlled by several tissue-specific and ubiquitous factors, but how these factors achieve looping, synapsis and V(D)J recombination has been a mystery. Now several studies provide evidence that non-coding transcription, often proposed to play a role, is indeed an important driver, and furthermore has a specific nuclear destination for recombination. Both local transcription-independent looping and longer range factor-mediated transcription-dependent looping play separate roles in altering AgR architecture to enable V(D)J recombination.
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Affiliation(s)
- Michael J T Stubbington
- Nuclear Dynamics Laboratory, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
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41
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Callen E, Faryabi RB, Luckey M, Hao B, Daniel JA, Yang W, Sun HW, Dressler G, Peng W, Chi H, Ge K, Krangel MS, Park JH, Nussenzweig A. The DNA damage- and transcription-associated protein paxip1 controls thymocyte development and emigration. Immunity 2012; 37:971-85. [PMID: 23159437 PMCID: PMC3525809 DOI: 10.1016/j.immuni.2012.10.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 10/04/2012] [Indexed: 01/21/2023]
Abstract
Histone 3 lysine 4 trimethylation (H3K4me3) is associated with promoters of active genes and found at hot spots for DNA recombination. Here we have shown that PAXIP1 (also known as PTIP), a protein associated with MLL3 and MLL4 methyltransferase and the DNA damage response, regulates RAG-mediated cleavage and repair during V(D)J recombination in CD4(+) CD8(+) DP thymocytes. Loss of PAXIP1 in developing thymocytes diminished Jα H3K4me3 and germline transcription, suppressed double strand break formation at 3' Jα segments, but resulted in accumulation of unresolved T cell receptor α-chain gene (Tcra) breaks. Moreover, PAXIP1 was essential for release of mature single positive (SP) αβ T cells from the thymus through transcriptional activation of sphingosine-1-phosphate receptor S1pr1 as well as for natural killer T cell development. Thus, in addition to maintaining genome integrity during Tcra rearrangements, PAXIP1 controls distinct transcriptional programs during DP differentiation necessary for Tcra locus accessibility, licensing mature thymocytes for trafficking and natural killer T cell development.
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Affiliation(s)
- Elsa Callen
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda MD 20892
| | - Robert B. Faryabi
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda MD 20892
| | - Megan Luckey
- Experimental Immunology Branch, National Cancer Institute, NIH, Bethesda MD 20892
| | - Bingtao Hao
- Department of Immunology, Campus Box 3010, Duke University Medical Center, Durham, NC 27710
| | - Jeremy A. Daniel
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda MD 20892
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Wenjing Yang
- Department of Physics, The George Washington University, Washington, DC 20052
| | - Hong-Wei Sun
- Biodata Mining and Discovery Section, Office of Science and Technology, NIH, Bethesda MD 20892
| | - Greg Dressler
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109, USA. 262 Danny Thomas Place, Room E-7013, Memphis, TN 38105-2794
| | - Weiqun Peng
- Department of Physics, The George Washington University, Washington, DC 20052
| | - Hongbo Chi
- Department of Immunology, St. Jude Children’s Research Hospital, Memphis TN 38105
| | - Kai Ge
- Laboratory of Endocrinology and Receptor Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda MD 20892
| | - Michael S. Krangel
- Department of Immunology, Campus Box 3010, Duke University Medical Center, Durham, NC 27710
| | - Jung-Hyun Park
- Experimental Immunology Branch, National Cancer Institute, NIH, Bethesda MD 20892
| | - André Nussenzweig
- Laboratory of Genome Integrity, National Cancer Institute, NIH, Bethesda MD 20892
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TRIM28 mediates chromatin modifications at the TCRα enhancer and regulates the development of T and natural killer T cells. Proc Natl Acad Sci U S A 2012; 109:20083-8. [PMID: 23169648 DOI: 10.1073/pnas.1214704109] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
T-cell receptor-α (TCRα) rearrangement in CD4(+)CD8(+) double-positive immature thymocytes is a prerequisite for production of αβ T cells and invariant natural killer T cells. This developmental event is regulated by the TCRα enhancer (Eα), which induces chromatin modification and recruitment of the recombination-activating proteins Rag1 and Rag2. However, the molecular mechanism underlying the activation and long-range action of Eα remains incompletely understood. We show here that the chromatin-modifying factor TRIM28 is highly expressed in double-positive thymocytes and persistently phosphorylated at serine 473. TRIM28 binds to Eα and induces histone 3 lysine 4 trimethylation in the Eα and distant regions of the TCRα locus, coupled with recruitment of Rag proteins. T-cell-conditional ablation of TRIM28 impaired TCRα gene rearrangement and compromised the development of αβ T cells and invariant natural killer T cells. These findings establish TRIM28 as a unique regulator of thymocyte development and highlight an epigenetic mechanism involving TRIM28-mediated active chromatin modification in the TCRα locus.
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Verma-Gaur J, Torkamani A, Schaffer L, Head SR, Schork NJ, Feeney AJ. Noncoding transcription within the Igh distal V(H) region at PAIR elements affects the 3D structure of the Igh locus in pro-B cells. Proc Natl Acad Sci U S A 2012; 109:17004-9. [PMID: 23027941 PMCID: PMC3479473 DOI: 10.1073/pnas.1208398109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Noncoding sense and antisense germ-line transcription within the Ig heavy chain locus precedes V(D)J recombination and has been proposed to be associated with Igh locus accessibility, although its precise role remains elusive. However, no global analysis of germ-line transcription throughout the Igh locus has been done. Therefore, we performed directional RNA-seq, demonstrating the locations and extent of both sense and antisense transcription throughout the Igh locus. Surprisingly, the majority of antisense transcripts are localized around two Pax5-activated intergenic repeat (PAIR) elements in the distal IghV region. Importantly, long-distance loops measured by chromosome conformation capture (3C) are observed between these two active PAIR promoters and Eμ, the start site of Iμ germ-line transcription, in a lineage- and stage-specific manner, even though this antisense transcription is Eμ-independent. YY1(-/-) pro-B cells are greatly impaired in distal V(H) gene rearrangement and Igh locus compaction, and we demonstrate that YY1 deficiency greatly reduces antisense transcription and PAIR-Eμ interactions. ChIP-seq shows high level YY1 binding only at Eμ, but low levels near some antisense promoters. PAIR-Eμ interactions are not disrupted by DRB, which blocks transcription elongation without disrupting transcription factories once they are established, but the looping is reduced after heat-shock treatment, which disrupts transcription factories. We propose that transcription-mediated interactions, most likely at transcription factories, initially compact the Igh locus, bringing distal V(H) genes close to the DJ(H) rearrangement which is adjacent to Eμ. Therefore, we hypothesize that one key role of noncoding germ-line transcription is to facilitate locus compaction, allowing distal V(H) genes to undergo efficient rearrangement.
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Affiliation(s)
- Jiyoti Verma-Gaur
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Ali Torkamani
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, and The Scripps Translational Science Institute, La Jolla, CA 92037; and
| | - Lana Schaffer
- Next Generation Sequencing Core Facility, The Scripps Research Institute, La Jolla, CA 92037
| | - Steven R. Head
- Next Generation Sequencing Core Facility, The Scripps Research Institute, La Jolla, CA 92037
| | - Nicholas J. Schork
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, and The Scripps Translational Science Institute, La Jolla, CA 92037; and
| | - Ann J. Feeney
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
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DNA-binding factor CTCF and long-range gene interactions in V(D)J recombination and oncogene activation. Blood 2012; 119:6209-18. [DOI: 10.1182/blood-2012-03-402586] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Abstract
Regulation of V(D)J recombination events at immunoglobulin (Ig) and T-cell receptor loci in lymphoid cells is complex and achieved via changes in substrate accessibility. Various studies over the last year have identified the DNA-binding zinc-finger protein CCCTC-binding factor (CTCF) as a crucial regulator of long-range chromatin interactions. CTCF often controls specific interactions by preventing inappropriate communication between neighboring regulatory elements or independent chromatin domains. Although recent gene targeting experiments demonstrated that the presence of the CTCF protein is not required for the process of V(D)J recombination per se, CTCF turned out to be essential to control order, lineage specificity and to balance the Ig V gene repertoire. Moreover, CTCF was shown to restrict activity of κ enhancer elements to the Ig κ locus. In this review, we discuss CTCF function in the regulation of V(D)J recombination on the basis of established knowledge on CTCF-mediated chromatin loop domains in various other loci, including the imprinted H19-Igf2 locus as well as the complex β-globin, MHC class II and IFN-γ loci. Moreover, we discuss that loss of CTCF-mediated restriction of enhancer activity may well contribute to oncogenic activation, when in chromosomal translocations Ig enhancer elements and oncogenes appear in a novel genomic context.
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45
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Begum NA, Honjo T. Evolutionary comparison of the mechanism of DNA cleavage with respect to immune diversity and genomic instability. Biochemistry 2012; 51:5243-56. [PMID: 22712724 DOI: 10.1021/bi3005895] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It is generally assumed that the genetic mechanism for immune diversity is unique and distinct from that for general genome diversity, in part because of the high efficiency and strict regulation of immune diversity. This expectation was partially met by the discovery of RAG1 and -2, which catalyze V(D)J recombination to generate the immune repertoire of B and T lymphocyte receptors. RAG1 and -2 were later shown to be derived from a transposon. On the other hand, activation-induced cytidine deaminase (AID), which mediates both somatic hypermutation (SHM) and the class-switch recombination (CSR) of the immunoglobulin genes, evolved earlier than RAG1 and -2 in jawless vertebrates. This review compares immune diversity and general genome diversity from an evolutionary perspective, shedding light on the roles of DNA-cleaving enzymes and target recognition markers. This comparison revealed that AID-mediated SHM and CSR share the cleaving enzyme topoisomerase 1 with transcription-associated mutation (TAM) and triplet contraction, which is involved in many genetic diseases. These genome-altering events appear to target DNA with non-B structure, which is induced by the inefficient correction of the excessive supercoiling that is caused by active transcription. Furthermore, an epigenetic modification on chromatin (histone H3K4 trimethylation) is used as a mark for DNA cleavage sites in meiotic recombination, V(D)J recombination, CSR, and SHM. We conclude that acquired immune diversity evolved via the appearance of an AID orthologue that utilized a preexisting mechanism for genomic instability, such as TAM.
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Affiliation(s)
- Nasim A Begum
- Department of Immunology and Genomic Medicine, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
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Berkowska MA, van der Burg M, van Dongen JJM, van Zelm MC. Checkpoints of B cell differentiation: visualizing Ig-centric processes. Ann N Y Acad Sci 2012; 1246:11-25. [PMID: 22236426 DOI: 10.1111/j.1749-6632.2011.06278.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The generation of antibody responses and B cell memory can only take place following multiple steps of differentiation. Key molecular processes during precursor B cell differentiation in bone marrow generate unique antibodies. These antibodies are further optimized via molecular modifications during immune responses in peripheral lymphoid organs. Multiple checkpoints ensure proper differentiation of precursor and mature B lymphocytes. Many of these checkpoints have been found disrupted in patients with a primary immunodeficiency. Based on studies in these patients and in mouse models, new insights have been generated in B cell differentiation and antibody responses. Still, in many patients with impaired antibody formation, it remains unclear how B cells are affected. In this perspective, we present 11 critical processes in B cell differentiation. We discuss how defects in these processes can result in impaired checkpoint selection and how they can be visualized in healthy subjects and patients with immunodeficiency or other immunological disease.
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Affiliation(s)
- Magdalena A Berkowska
- Department of Immunology, Erasmus MC, University Medical Center, Rotterdam, the Netherlands
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47
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Aoki-Ota M, Torkamani A, Ota T, Schork N, Nemazee D. Skewed primary Igκ repertoire and V-J joining in C57BL/6 mice: implications for recombination accessibility and receptor editing. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2012; 188:2305-15. [PMID: 22287713 PMCID: PMC3288532 DOI: 10.4049/jimmunol.1103484] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Previous estimates of the diversity of the mouse Ab repertoire have been based on fragmentary data as a result of many technical limitations, in particular, the many samples necessary to provide adequate coverage. In this study, we used 5'-coding end amplification of Igκ mRNAs from bone marrow, splenic, and lymph node B cells of C57BL/6 mice combined with amplicon pyrosequencing to assess the functional and nonfunctional Vκ repertoire. To evaluate the potential effects of receptor editing, we also compared V/J associations and usage in bone marrows of mouse mutants under constitutive negative selection or an altered ability to undergo secondary recombination. To focus on preimmune B cells, our cell sorting strategy excluded memory B cells and plasma cells. Analysis of ~90 Mbp, representing >250,000 individual transcripts from 59 mice, revealed that 101 distinct functional Vκ genes are used but at frequencies ranging from ~0.001 to ~10%. Usage of seven Vκ genes made up >40% of the repertoire. A small class of transcripts from apparently nonfunctional Vκ genes was found, as were occasional transcripts from several apparently functional genes that carry aberrant recombination signals. Of 404 potential V-J combinations (101 Vκs × 4 Jκs), 398 (98.5%) were found at least once in our sample. For most Vκ transcripts, all Jκs were used, but V-J association biases were common. Usage patterns were remarkably stable in different selective conditions. Overall, the primary κ repertoire is highly skewed by preferred rearrangements, limiting Ab diversity, but potentially facilitating receptor editing.
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Affiliation(s)
- Miyo Aoki-Ota
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037
| | - Ali Torkamani
- Translational Sciences Institute, The Scripps Research Institute, La Jolla, California 92037
| | - Takayuki Ota
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037
| | - Nicholas Schork
- Translational Sciences Institute, The Scripps Research Institute, La Jolla, California 92037
| | - David Nemazee
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037
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Highly diverse TCRα chain repertoire of pre-immune CD8⁺ T cells reveals new insights in gene recombination. EMBO J 2012; 31:1666-78. [PMID: 22373576 DOI: 10.1038/emboj.2012.48] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 02/02/2012] [Indexed: 01/13/2023] Open
Abstract
Although the T-cell receptor αδ (TCRαδ) locus harbours large libraries of variable (TRAV) and junctional (TRAJ) gene segments, according to previous studies the TCRα chain repertoire is of limited diversity due to restrictions imposed by sequential coordinate TRAV-TRAJ recombinations. By sequencing tens of millions of TCRα chain transcripts from naive mouse CD8(+) T cells, we observed a hugely diverse repertoire, comprising nearly all possible TRAV-TRAJ combinations. Our findings are not compatible with sequential coordinate gene recombination, but rather with a model in which contraction and DNA looping in the TCRαδ locus provide equal access to TRAV and TRAJ gene segments, similarly to that demonstrated for IgH gene recombination. Generation of the observed highly diverse TCRα chain repertoire necessitates deletion of failed attempts by thymic-positive selection and is essential for the formation of highly diverse TCRαβ repertoires, capable of providing good protective immunity.
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del Blanco B, García-Mariscal A, Wiest DL, Hernández-Munain C. Tcra enhancer activation by inducible transcription factors downstream of pre-TCR signaling. THE JOURNAL OF IMMUNOLOGY 2012; 188:3278-93. [PMID: 22357628 DOI: 10.4049/jimmunol.1100271] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The Tcra enhancer (Eα) is essential for pre-TCR-mediated activation of germline transcription and V(D)J recombination. Eα is considered an archetypical enhanceosome that acts through the functional synergy and cooperative binding of multiple transcription factors. Based on dimethylsulfate genomic footprinting experiments, there has been a long-standing paradox regarding Eα activation in the absence of differences in enhancer occupancy. Our data provide the molecular mechanism of Eα activation and an explanation of this paradox. We found that germline transcriptional activation of Tcra is dependent on constant phospholipase Cγ, as well as calcineurin- and MAPK/ERK-mediated signaling, indicating that inducible transcription factors are crucially involved. NFAT, AP-1, and early growth response factor 1, together with CREB-binding protein/p300 coactivators, bind to Eα as part of an active enhanceosome assembled during pre-TCR signaling. We favor a scenario in which the binding of lymphoid-restricted and constitutive transcription factors to Eα prior to its activation forms a regulatory scaffold to recruit factors induced by pre-TCR signaling. Thus, the combinatorial assembly of tissue- and signal-specific transcription factors dictates the Eα function. This mechanism for enhancer activation may represent a general paradigm in tissue-restricted and stimulus-responsive gene regulation.
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Affiliation(s)
- Beatriz del Blanco
- Departamento de Biología Celular e Inmunología, Instituto de Parasitología y Biomedicina López-Neyra (IPBLN-CSIC), Consejo Superior de Investigaciones Científicas, 18100-Armilla, Granada, Spain
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Stone JL, McMillan RE, Skaar DA, Bradshaw JM, Jirtle RL, Sikes ML. DNA double-strand breaks relieve USF-mediated repression of Dβ2 germline transcription in developing thymocytes. THE JOURNAL OF IMMUNOLOGY 2012; 188:2266-75. [PMID: 22287717 DOI: 10.4049/jimmunol.1002931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Activation of germline promoters is central to V(D)J recombinational accessibility, driving chromatin remodeling, nucleosome repositioning, and transcriptional read-through of associated DNA. We have previously shown that of the two TCRβ locus (Tcrb) D segments, Dβ1 is flanked by an upstream promoter that directs its transcription and recombinational accessibility. In contrast, transcription within the DJβ2 segment cluster is initially restricted to the J segments and only redirected upstream of Dβ2 after D-to-J joining. The repression of upstream promoter activity prior to Tcrb assembly correlates with evidence that suggests DJβ2 recombination is less efficient than that of DJβ1. Because inefficient DJβ2 assembly offers the potential for V-to-DJβ2 recombination to rescue frameshifted V-to-DJβ1 joints, we wished to determine how Dβ2 promoter activity is modulated upon Tcrb recombination. In this study, we show that repression of the otherwise transcriptionally primed 5'Dβ2 promoter requires binding of upstream stimulatory factor (USF)-1 to a noncanonical E-box within the Dβ2 12-recombination signal sequence spacer prior to Tcrb recombination. USF binding is lost from both rearranged and germline Dβ2 sites in DNA-dependent protein kinase, catalytic subunit-competent thymocytes. Finally, genotoxic dsDNA breaks lead to rapid loss of USF binding and gain of transcriptionally primed 5'Dβ2 promoter activity in a DNA-dependent protein kinase, catalytic subunit-dependent manner. Together, these data suggest a mechanism by which V(D)J recombination may feed back to regulate local Dβ2 recombinational accessibility during thymocyte development.
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Affiliation(s)
- Jennifer L Stone
- Department of Microbiology, North Carolina State University, Raleigh, NC 27695, USA
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