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Martin EC, Le Targa L, Tsakou-Ngouafo L, Fan TP, Lin CY, Xiao J, Huang Z, Yuan S, Xu A, Su YH, Petrescu AJ, Pontarotti P, Schatz DG. Insights into RAG Evolution from the Identification of "Missing Link" Family A RAGL Transposons. Mol Biol Evol 2023; 40:msad232. [PMID: 37850912 PMCID: PMC10629977 DOI: 10.1093/molbev/msad232] [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: 08/09/2023] [Revised: 09/28/2023] [Accepted: 10/10/2023] [Indexed: 10/19/2023] Open
Abstract
A series of "molecular domestication" events are thought to have converted an invertebrate RAG-like (RAGL) transposase into the RAG1-RAG2 (RAG) recombinase, a critical enzyme for adaptive immunity in jawed vertebrates. The timing and order of these events are not well understood, in part because of a dearth of information regarding the invertebrate RAGL-A transposon family. In contrast to the abundant and divergent RAGL-B transposon family, RAGL-A most closely resembles RAG and is represented by a single orphan RAG1-like (RAG1L) gene in the genome of the hemichordate Ptychodera flava (PflRAG1L-A). Here, we provide evidence for the existence of complete RAGL-A transposons in the genomes of P. flava and several echinoderms. The predicted RAG1L-A and RAG2L-A proteins encoded by these transposons intermingle sequence features of jawed vertebrate RAG and RAGL-B transposases, leading to a prediction of DNA binding, catalytic, and transposition activities that are a hybrid of RAG and RAGL-B. Similarly, the terminal inverted repeats (TIRs) of the RAGL-A transposons combine features of both RAGL-B transposon TIRs and RAG recombination signal sequences. Unlike all previously described RAG2L proteins, RAG2L-A proteins contain an acidic hinge region, which we demonstrate is capable of efficiently inhibiting RAG-mediated transposition. Our findings provide evidence for a critical intermediate in RAG evolution and argue that certain adaptations thought to be specific to jawed vertebrates (e.g. the RAG2 acidic hinge) actually arose in invertebrates, thereby focusing attention on other adaptations as the pivotal steps in the completion of RAG domestication in jawed vertebrates.
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Affiliation(s)
- Eliza C Martin
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520-8011, USA
| | - Lorlane Le Targa
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille 13005, France
| | - Louis Tsakou-Ngouafo
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille 13005, France
| | - Tzu-Pei Fan
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Che-Yi Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Jianxiong Xiao
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520-8011, USA
| | - Ziwen Huang
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Shaochun Yuan
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Anlong Xu
- State Key Laboratory of Biocontrol, Guangdong Key Laboratory of Pharmaceutical Functional Genes, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
- School of Life Sciences, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Yi-Hsien Su
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei 11529, Taiwan
| | - Andrei-Jose Petrescu
- Department of Bioinformatics and Structural Biochemistry, Institute of Biochemistry of the Romanian Academy, 060031 Bucharest, Romania
| | - Pierre Pontarotti
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille 13005, France
- CNRS SNC 5039, 13005 Marseille, France
| | - David G Schatz
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520-8011, USA
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Martin EC, Le Targa L, Tsakou-Ngouafo L, Fan TP, Lin CY, Xiao J, Su YH, Petrescu AJ, Pontarotti P, Schatz DG. Insights into RAG evolution from the identification of "missing link" family A RAGL transposons. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.20.553239. [PMID: 37645967 PMCID: PMC10462144 DOI: 10.1101/2023.08.20.553239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
A series of "molecular domestication" events are thought to have converted an invertebrate RAG-like (RAGL) transposase into the RAG1-RAG2 (RAG) recombinase, a critical enzyme for adaptive immunity in jawed vertebrates. The timing and order of these events is not well understood, in part because of a dearth of information regarding the invertebrate RAGL-A transposon family. In contrast to the abundant and divergent RAGL-B transposon family, RAGL-A most closely resembles RAG and is represented by a single orphan RAG1-like (RAG1L) gene in the genome of the hemichordate Ptychodera flava (PflRAG1L-A). Here, we provide evidence for the existence of complete RAGL-A transposons in the genomes of P. flava and several echinoderms. The predicted RAG1L-A and RAG2L-A proteins encoded by these transposons intermingle sequence features of jawed vertebrate RAG and RAGL-B transposases, leading to a prediction of DNA binding, catalytic, and transposition activities that are a hybrid of RAG and RAGL-B. Similarly, the terminal inverted repeats (TIRs) of the RAGL-A transposons combine features of both RAGL-B transposon TIRs and RAG recombination signal sequences. Unlike all previously described RAG2L proteins, PflRAG2L-A and echinoderm RAG2L-A contain an acidic hinge region, which we demonstrate is capable of efficiently inhibiting RAG-mediated transposition. Our findings provide evidence for a critical intermediate in RAG evolution and argue that certain adaptations thought to be specific to jawed vertebrates (e.g., the RAG2 acidic hinge) actually arose in invertebrates, thereby focusing attention on other adaptations as the pivotal steps in the completion of RAG domestication in jawed vertebrates.
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Affiliation(s)
- Eliza C. Martin
- Department of Immunobiology, Yale School of Medicine, 300 Cedar Street, Box 208011, New Haven, CT, 06520-8011, United States
| | - Lorlane Le Targa
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille France
| | - Louis Tsakou-Ngouafo
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille France
| | - Tzu-Pei Fan
- Institute of Cellular and Organismic Biology, Academia Sinica, 128 Academia Rd., Sec. 2, Nankang, Taipei 11529, Taiwan
| | - Che-Yi Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, 128 Academia Rd., Sec. 2, Nankang, Taipei 11529, Taiwan
| | - Jianxiong Xiao
- Department of Immunobiology, Yale School of Medicine, 300 Cedar Street, Box 208011, New Haven, CT, 06520-8011, United States
| | - Yi Hsien Su
- Institute of Cellular and Organismic Biology, Academia Sinica, 128 Academia Rd., Sec. 2, Nankang, Taipei 11529, Taiwan
| | - Andrei-Jose Petrescu
- Department of Bioinformatics and Structural Biochemistry, Institute of Biochemistry of the Romanian Academy, Splaiul Independentei 296, 060031, Bucharest, Romania
| | - Pierre Pontarotti
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille France
- CNRS SNC 5039, 13005 Marseille, France
| | - David G. Schatz
- Department of Immunobiology, Yale School of Medicine, 300 Cedar Street, Box 208011, New Haven, CT, 06520-8011, United States
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Braams M, Pike-Overzet K, Staal FJT. The recombinase activating genes: architects of immune diversity during lymphocyte development. Front Immunol 2023; 14:1210818. [PMID: 37497222 PMCID: PMC10367010 DOI: 10.3389/fimmu.2023.1210818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2023] [Accepted: 06/19/2023] [Indexed: 07/28/2023] Open
Abstract
The mature lymphocyte population of a healthy individual has the remarkable ability to recognise an immense variety of antigens. Instead of encoding a unique gene for each potential antigen receptor, evolution has used gene rearrangements, also known as variable, diversity, and joining gene segment (V(D)J) recombination. This process is critical for lymphocyte development and relies on recombination-activating genes-1 (RAG1) and RAG2, here collectively referred to as RAG. RAG serves as powerful genome editing tools for lymphocytes and is strictly regulated to prevent dysregulation. However, in the case of dysregulation, RAG has been implicated in cases of cancer, autoimmunity and severe combined immunodeficiency (SCID). This review examines functional protein domains and motifs of RAG, describes advances in our understanding of the function and (dys)regulation of RAG, discuss new therapeutic options, such as gene therapy, for RAG deficiencies, and explore in vitro and in vivo methods for determining RAG activity and target specificity.
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Affiliation(s)
- Merijn Braams
- Department of Immunology, Leiden University Medical Centre, Leiden, Netherlands
| | - Karin Pike-Overzet
- Department of Immunology, Leiden University Medical Centre, Leiden, Netherlands
| | - Frank J. T. Staal
- Department of Immunology, Leiden University Medical Centre, Leiden, Netherlands
- Novo Nordisk Foundation Centre for Stem Cell Medicine (reNEW), Leiden University Medical Centre, Leiden, Netherlands
- Department of Paediatrics, Leiden University Medical Centre, Leiden, Netherlands
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Abstract
Adaptive immunity in jawed vertebrates relies on the assembly of antigen receptor genes by the recombination activating gene 1 (RAG1)-RAG2 (collectively RAG) recombinase in a reaction known as V(D)J recombination. Extensive biochemical and structural evidence indicates that RAG and V(D)J recombination evolved from the components of a RAG-like (RAGL) transposable element through a process known as transposon molecular domestication. This Review describes recent advances in our understanding of the functional and structural transitions that occurred during RAG evolution. We use the structures of RAG and RAGL enzymes to trace the evolutionary adaptations that yielded a RAG recombinase with exquisitely regulated cleavage activity and a multilayered array of mechanisms to suppress transposition. We describe how changes in modes of DNA binding, alterations in the dynamics of protein-DNA complexes, single amino acid mutations and a modular design likely enabled RAG family enzymes to survive and spread in the genomes of eukaryotes. These advances highlight the insight that can be gained from viewing evolution of vertebrate immunity through the lens of comparative genome analyses coupled with structural biology and biochemistry.
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Bai W, Zhao B, Gu M, Dong J. Alternative end-joining in BCR gene rearrangements and translocations. Acta Biochim Biophys Sin (Shanghai) 2022; 54:782-795. [PMID: 35593472 PMCID: PMC9828324 DOI: 10.3724/abbs.2022051] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Programmed DNA double-strand breaks (DSBs) occur during antigen receptor gene recombination, namely V(D)J recombination in developing B lymphocytes and class switch recombination (CSR) in mature B cells. Repair of these DSBs by classical end-joining (c-NHEJ) enables the generation of diverse BCR repertoires for efficient humoral immunity. Deletion of or mutation in c-NHEJ genes in mice and humans confer various degrees of primary immune deficiency and predisposition to lymphoid malignancies that often harbor oncogenic chromosomal translocations. In the absence of c-NHEJ, alternative end-joining (A-EJ) catalyzes robust CSR and to a much lesser extent, V(D)J recombination, but the mechanisms of A-EJ are only poorly defined. In this review, we introduce recent advances in the understanding of A-EJ in the context of V(D)J recombination and CSR with emphases on DSB end processing, DNA polymerases and ligases, and discuss the implications of A-EJ to lymphoid development and chromosomal translocations.
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Affiliation(s)
- Wanyu Bai
- Department of ImmunologyZhongshan School of MedicineSun Yat-sen UniversityGuangzhou510080China,Key Laboratory of Tropical Disease Control (Sun Yat-sen University)Ministry of EducationGuangzhou510080China
| | - Bo Zhao
- Department of ImmunologyZhongshan School of MedicineSun Yat-sen UniversityGuangzhou510080China,Key Laboratory of Tropical Disease Control (Sun Yat-sen University)Ministry of EducationGuangzhou510080China
| | - Mingyu Gu
- Department of ImmunologyZhongshan School of MedicineSun Yat-sen UniversityGuangzhou510080China,Key Laboratory of Tropical Disease Control (Sun Yat-sen University)Ministry of EducationGuangzhou510080China
| | - Junchao Dong
- Department of ImmunologyZhongshan School of MedicineSun Yat-sen UniversityGuangzhou510080China,Key Laboratory of Tropical Disease Control (Sun Yat-sen University)Ministry of EducationGuangzhou510080China,Correspondence address. Tel: +86-20-87330571; E-mail:
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6
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Luo S, Qiao R, Zhang X. DNA Damage Response and Repair in Adaptive Immunity. Front Cell Dev Biol 2022; 10:884873. [PMID: 35663402 PMCID: PMC9157429 DOI: 10.3389/fcell.2022.884873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 03/31/2022] [Indexed: 11/16/2022] Open
Abstract
The diversification of B-cell receptor (BCR), as well as its secreted product, antibody, is a hallmark of adaptive immunity, which has more specific roles in fighting against pathogens. The antibody diversification is from recombination-activating gene (RAG)-initiated V(D)J recombination, activation-induced cytidine deaminase (AID)-initiated class switch recombination (CSR), and V(D)J exon somatic hypermutation (SHM). The proper repair of RAG- and AID-initiated DNA lesions and double-strand breaks (DSBs) is required for promoting antibody diversification, suppressing genomic instability, and oncogenic translocations. DNA damage response (DDR) factors and DSB end-joining factors are recruited to the RAG- and AID-initiated DNA lesions and DSBs to coordinately resolve them for generating productive recombination products during antibody diversification. Recently, cohesin-mediated loop extrusion is proposed to be the underlying mechanism of V(D)J recombination and CSR, which plays essential roles in promoting the orientation-biased deletional end-joining . Here, we will discuss the mechanism of DNA damage repair in antibody diversification.
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Affiliation(s)
- Sha Luo
- Biomedical Pioneering Innovation Center, Innovation Center for Genomics, Peking University, Beijing, China
- Academy for Advanced Interdisciplinery Studies, Peking University, Beijing, China
| | - Ruolin Qiao
- Biomedical Pioneering Innovation Center, Innovation Center for Genomics, Peking University, Beijing, China
- Academy for Advanced Interdisciplinery Studies, Peking University, Beijing, China
| | - Xuefei Zhang
- Biomedical Pioneering Innovation Center, Innovation Center for Genomics, Peking University, Beijing, China
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7
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Christie SM, Fijen C, Rothenberg E. V(D)J Recombination: Recent Insights in Formation of the Recombinase Complex and Recruitment of DNA Repair Machinery. Front Cell Dev Biol 2022; 10:886718. [PMID: 35573672 PMCID: PMC9099191 DOI: 10.3389/fcell.2022.886718] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/01/2022] [Indexed: 11/13/2022] Open
Abstract
V(D)J recombination is an essential mechanism of the adaptive immune system, producing a diverse set of antigen receptors in developing lymphocytes via regulated double strand DNA break and subsequent repair. DNA cleavage is initiated by the recombinase complex, consisting of lymphocyte specific proteins RAG1 and RAG2, while the repair phase is completed by classical non-homologous end joining (NHEJ). Many of the individual steps of this process have been well described and new research has increased the scale to understand the mechanisms of initiation and intermediate stages of the pathway. In this review we discuss 1) the regulatory functions of RAGs, 2) recruitment of RAGs to the site of recombination and formation of a paired complex, 3) the transition from a post-cleavage complex containing RAGs and cleaved DNA ends to the NHEJ repair phase, and 4) the potential redundant roles of certain factors in repairing the break. Regulatory (non-core) domains of RAGs are not necessary for catalytic activity, but likely influence recruitment and stabilization through interaction with modified histones and conformational changes. To form long range paired complexes, recent studies have found evidence in support of large scale chromosomal contraction through various factors to utilize diverse gene segments. Following the paired cleavage event, four broken DNA ends must now make a regulated transition to the repair phase, which can be controlled by dynamic conformational changes and post-translational modification of the factors involved. Additionally, we examine the overlapping roles of certain NHEJ factors which allows for prevention of genomic instability due to incomplete repair in the absence of one, but are lethal in combined knockouts. To conclude, we focus on the importance of understanding the detail of these processes in regards to off-target recombination or deficiency-mediated clinical manifestations.
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Affiliation(s)
- Shaun M. Christie
- *Correspondence: Shaun M. Christie, ; Carel Fijen, ; Eli Rothenberg,
| | - Carel Fijen
- *Correspondence: Shaun M. Christie, ; Carel Fijen, ; Eli Rothenberg,
| | - Eli Rothenberg
- *Correspondence: Shaun M. Christie, ; Carel Fijen, ; Eli Rothenberg,
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Libri A, Marton T, Deriano L. The (Lack of) DNA Double-Strand Break Repair Pathway Choice During V(D)J Recombination. Front Genet 2022; 12:823943. [PMID: 35082840 PMCID: PMC8785701 DOI: 10.3389/fgene.2021.823943] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 12/13/2021] [Indexed: 01/08/2023] Open
Abstract
DNA double-strand breaks (DSBs) are highly toxic lesions that can be mended via several DNA repair pathways. Multiple factors can influence the choice and the restrictiveness of repair towards a given pathway in order to warrant the maintenance of genome integrity. During V(D)J recombination, RAG-induced DSBs are (almost) exclusively repaired by the non-homologous end-joining (NHEJ) pathway for the benefit of antigen receptor gene diversity. Here, we review the various parameters that constrain repair of RAG-generated DSBs to NHEJ, including the peculiarity of DNA DSB ends generated by the RAG nuclease, the establishment and maintenance of a post-cleavage synaptic complex, and the protection of DNA ends against resection and (micro)homology-directed repair. In this physiological context, we highlight that certain DSBs have limited DNA repair pathway choice options.
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Affiliation(s)
- Alice Libri
- Genome Integrity, Immunity and Cancer Unit, Institut Pasteur, Université de Paris, INSERM U1223, Equipe Labellisée Ligue Contre Le Cancer, Paris, France
| | - Timea Marton
- Genome Integrity, Immunity and Cancer Unit, Institut Pasteur, Université de Paris, INSERM U1223, Equipe Labellisée Ligue Contre Le Cancer, Paris, France
| | - Ludovic Deriano
- Genome Integrity, Immunity and Cancer Unit, Institut Pasteur, Université de Paris, INSERM U1223, Equipe Labellisée Ligue Contre Le Cancer, Paris, France
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Frock RL, Sadeghi C, Meng J, Wang JL. DNA End Joining: G0-ing to the Core. Biomolecules 2021; 11:biom11101487. [PMID: 34680120 PMCID: PMC8533500 DOI: 10.3390/biom11101487] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/05/2021] [Accepted: 10/06/2021] [Indexed: 12/28/2022] Open
Abstract
Humans have evolved a series of DNA double-strand break (DSB) repair pathways to efficiently and accurately rejoin nascently formed pairs of double-stranded DNA ends (DSEs). In G0/G1-phase cells, non-homologous end joining (NHEJ) and alternative end joining (A-EJ) operate to support covalent rejoining of DSEs. While NHEJ is predominantly utilized and collaborates extensively with the DNA damage response (DDR) to support pairing of DSEs, much less is known about A-EJ collaboration with DDR factors when NHEJ is absent. Non-cycling lymphocyte progenitor cells use NHEJ to complete V(D)J recombination of antigen receptor genes, initiated by the RAG1/2 endonuclease which holds its pair of targeted DSBs in a synapse until each specified pair of DSEs is handed off to the NHEJ DSB sensor complex, Ku. Similar to designer endonuclease DSBs, the absence of Ku allows for A-EJ to access RAG1/2 DSEs but with random pairing to complete their repair. Here, we describe recent insights into the major phases of DSB end joining, with an emphasis on synapsis and tethering mechanisms, and bring together new and old concepts of NHEJ vs. A-EJ and on RAG2-mediated repair pathway choice.
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10
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Chong S, Mir M. Towards Decoding the Sequence-Based Grammar Governing the Functions of Intrinsically Disordered Protein Regions. J Mol Biol 2020; 433:166724. [PMID: 33248138 DOI: 10.1016/j.jmb.2020.11.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 11/14/2020] [Accepted: 11/19/2020] [Indexed: 01/03/2023]
Abstract
A substantial portion of the proteome consists of intrinsically disordered regions (IDRs) that do not fold into well-defined 3D structures yet perform numerous biological functions and are associated with a broad range of diseases. It has been a long-standing enigma how different IDRs successfully execute their specific functions. Further putting a spotlight on IDRs are recent discoveries of functionally relevant biomolecular assemblies, which in some cases form through liquid-liquid phase separation. At the molecular level, the formation of biomolecular assemblies is largely driven by weak, multivalent, but selective IDR-IDR interactions. Emerging experimental and computational studies suggest that the primary amino acid sequences of IDRs encode a variety of their interaction behaviors. In this review, we focus on findings and insights that connect sequence-derived features of IDRs to their conformations, propensities to form biomolecular assemblies, selectivity of interaction partners, functions in the context of physiology and disease, and regulation of function. We also discuss directions of future research to facilitate establishing a comprehensive sequence-function paradigm that will eventually allow prediction of selective interactions and specificity of function mediated by IDRs.
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Affiliation(s)
- Shasha Chong
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, United States; The Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA 94720, United States.
| | - Mustafa Mir
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA 94720, United States
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11
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Meek K. Activation of DNA-PK by hairpinned DNA ends reveals a stepwise mechanism of kinase activation. Nucleic Acids Res 2020; 48:9098-9108. [PMID: 32716029 PMCID: PMC7498359 DOI: 10.1093/nar/gkaa614] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 07/08/2020] [Accepted: 07/14/2020] [Indexed: 12/12/2022] Open
Abstract
As its name implies, the DNA dependent protein kinase (DNA-PK) requires DNA double-stranded ends for enzymatic activation. Here, I demonstrate that hairpinned DNA ends are ineffective for activating the kinase toward many of its well-studied substrates (p53, XRCC4, XLF, HSP90). However, hairpinned DNA ends robustly stimulate certain DNA-PK autophosphorylations. Specifically, autophosphorylation sites within the ABCDE cluster are robustly phosphorylated when DNA-PK is activated by hairpinned DNA ends. Of note, phosphorylation of the ABCDE sites is requisite for activation of the Artemis nuclease that associates with DNA-PK to mediate hairpin opening. This finding suggests a multi-step mechanism of kinase activation. Finally, I find that all non-homologous end joining (NHEJ) defective cells (whether deficient in components of the DNA-PK complex or components of the ligase complex) are similarly deficient in joining DNA double-stranded breaks (DSBs) with hairpinned termini.
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Affiliation(s)
- Katheryn Meek
- Department of Microbiology & Molecular Genetics, and Department of Pathobiology & Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
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12
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Zhang Y, Cheng TC, Huang G, Lu Q, Surleac MD, Mandell JD, Pontarotti P, Petrescu AJ, Xu A, Xiong Y, Schatz DG. Transposon molecular domestication and the evolution of the RAG recombinase. Nature 2019; 569:79-84. [PMID: 30971819 PMCID: PMC6494689 DOI: 10.1038/s41586-019-1093-7] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 03/07/2019] [Indexed: 12/11/2022]
Abstract
Domestication of a transposon (a DNA sequence that can change its position in a genome) to give rise to the RAG1-RAG2 recombinase (RAG) and V(D)J recombination, which produces the diverse repertoire of antibodies and T cell receptors, was a pivotal event in the evolution of the adaptive immune system of jawed vertebrates. The evolutionary adaptations that transformed the ancestral RAG transposase into a RAG recombinase with appropriately regulated DNA cleavage and transposition activities are not understood. Here, beginning with cryo-electron microscopy structures of the amphioxus ProtoRAG transposase (an evolutionary relative of RAG), we identify amino acid residues and domains the acquisition or loss of which underpins the propensity of RAG for coupled cleavage, its preference for asymmetric DNA substrates and its inability to perform transposition in cells. In particular, we identify two adaptations specific to jawed-vertebrates-arginine 848 in RAG1 and an acidic region in RAG2-that together suppress RAG-mediated transposition more than 1,000-fold. Our findings reveal a two-tiered mechanism for the suppression of RAG-mediated transposition, illuminate the evolution of V(D)J recombination and provide insight into the principles that govern the molecular domestication of transposons.
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Affiliation(s)
- Yuhang Zhang
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - Tat Cheung Cheng
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | | | - Qingyi Lu
- Beijing University of Chinese Medicine, Beijing, China
| | - Marius D Surleac
- Department of Bioinformatics and Structural Biochemistry, Institute of Biochemistry of the Romanian Academy, Bucharest, Romania
| | - Jeffrey D Mandell
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA
| | - Pierre Pontarotti
- Aix Marseille Univ IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille, France.,Centre National de la Recherche Scientifique, Marseille, France
| | - Andrei J Petrescu
- Department of Bioinformatics and Structural Biochemistry, Institute of Biochemistry of the Romanian Academy, Bucharest, Romania
| | - Anlong Xu
- Beijing University of Chinese Medicine, Beijing, China. .,State Key Laboratory of Biocontrol, Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, Department of Biochemistry, School of Life Sciences, Sun Yat-sen University, Higher Education Mega Center, Guangzhou, China.
| | - Yong Xiong
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
| | - David G Schatz
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, USA.
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13
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Cut-and-Run: A Distinct Mechanism by which V(D)J Recombination Causes Genome Instability. Mol Cell 2019; 74:584-597.e9. [PMID: 30905508 PMCID: PMC6509286 DOI: 10.1016/j.molcel.2019.02.025] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 12/20/2018] [Accepted: 02/14/2019] [Indexed: 12/28/2022]
Abstract
V(D)J recombination is essential to generate antigen receptor diversity but is also a potent cause of genome instability. Many chromosome alterations that result from aberrant V(D)J recombination involve breaks at single recombination signal sequences (RSSs). A long-standing question, however, is how such breaks occur. Here, we show that the genomic DNA that is excised during recombination, the excised signal circle (ESC), forms a complex with the recombinase proteins to efficiently catalyze breaks at single RSSs both in vitro and in vivo. Following cutting, the RSS is released while the ESC-recombinase complex remains intact to potentially trigger breaks at further RSSs. Consistent with this, chromosome breaks at RSSs increase markedly in the presence of the ESC. Notably, these breaks co-localize with those found in acute lymphoblastic leukemia patients and occur at key cancer driver genes. We have named this reaction “cut-and-run” and suggest that it could be a significant cause of lymphocyte genome instability. A complex between the recombination by-product and RAGs triggers multiple DNA breaks The breaks co-localize with chromosome breakpoints in acute lymphoblastic leukemias The breaks occur at many frequently mutated genes in acute lymphoblastic leukemia Cut-and-run may underpin the most common types of lymphocyte chromosome instabilities
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14
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Dorna MB, Barbosa PFA, Rangel-Santos A, Csomos K, Ujhazi B, Dasso JF, Thwaites D, Boyes J, Savic S, Walter JE. Combined Immunodeficiency With Late-Onset Progressive Hypogammaglobulinemia and Normal B Cell Count in a Patient With RAG2 Deficiency. Front Pediatr 2019; 7:122. [PMID: 31058115 PMCID: PMC6477099 DOI: 10.3389/fped.2019.00122] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/12/2019] [Indexed: 11/13/2022] Open
Abstract
Proteins expressed by recombination activating genes 1 and 2 (RAG1/2) are essential in the process of V(D)J recombination that leads to generation of the T and B cell repertoires. Clinical and immunological phenotypes of patients with RAG deficiencies correlate well to the degree of impaired RAG activity and this has been expanding to variants of combined immunodeficiency (CID) or even milder antibody deficiency syndromes. Pathogenic variants that severely impair recombinase activity of RAG1/2 determine a severe combined immunodeficiency (SCID) phenotype, whereas hypomorphic variants result in leaky (partial) SCID and other immunodeficiencies. We report a patient with novel pathogenic compound heterozygous RAG2 variants that result in a CID phenotype with two distinctive characteristics: late-onset progressive hypogammaglobulinemia and highly elevated B cell count. In addition, the patient had early onset of infections, T cell lymphopenia and expansion of lymphocytes after exposure to herpes family viruses. This case highlights the importance of considering pathogenic RAG variants among patients with preserved B cell count and CID phenotype.
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Affiliation(s)
- Mayra B Dorna
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Pamela F A Barbosa
- Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Andréia Rangel-Santos
- Laboratory of Medical Investigation (LIM 36), Department of Pediatrics, Faculdade de Medicina da Universidade de São Paulo, Hospital das Clínicas, São Paulo, Brazil
| | - Krisztian Csomos
- Division of Allergy and Immunology, Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Boglarka Ujhazi
- Division of Allergy and Immunology, Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Joseph F Dasso
- Division of Allergy and Immunology, Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.,Department of Biology, University of Tampa, Tampa, FL, United States
| | - Daniel Thwaites
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Joan Boyes
- School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Sinisa Savic
- Department of Clinical Immunology and Allergy, Leeds Institute of Rheumatic and Musculoskeletal Medicine, St. James's University Hospital, Leeds, United Kingdom
| | - Jolan E Walter
- Division of Allergy and Immunology, Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL, United States.,Johns Hopkins All Children's Hospital, St. Petersburg, FL, United States.,Massachusetts General Hospital, Boston, MA, United States
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15
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Villa A, Notarangelo LD. RAG gene defects at the verge of immunodeficiency and immune dysregulation. Immunol Rev 2019; 287:73-90. [PMID: 30565244 PMCID: PMC6309314 DOI: 10.1111/imr.12713] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 08/21/2018] [Indexed: 12/18/2022]
Abstract
Mutations of the recombinase activating genes (RAG) in humans underlie a broad spectrum of clinical and immunological phenotypes that reflect different degrees of impairment of T- and B-cell development and alterations of mechanisms of central and peripheral tolerance. Recent studies have shown that this phenotypic heterogeneity correlates, albeit imperfectly, with different levels of recombination activity of the mutant RAG proteins. Furthermore, studies in patients and in newly developed animal models carrying hypomorphic RAG mutations have disclosed various mechanisms underlying immune dysregulation in this condition. Careful annotation of clinical outcome and immune reconstitution in RAG-deficient patients who have received hematopoietic stem cell transplantation has shown that progress has been made in the treatment of this disease, but new approaches remain to be tested to improve stem cell engraftment and durable immune reconstitution. Finally, initial attempts have been made to treat RAG deficiency with gene therapy.
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Affiliation(s)
- Anna Villa
- San Raffaele Telethon Institute for Gene Therapy (SR-TIGET), Division of Regenerative Medicine, Stem Cell and Gene Therapy, San Raffaele Scientific Institute, Milan, Italy
- Milan Unit, Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Milan, Italy
| | - Luigi D Notarangelo
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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16
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The RAG-2 Inhibitory Domain Gates Accessibility of the V(D)J Recombinase to Chromatin. Mol Cell Biol 2018; 38:MCB.00159-18. [PMID: 29760281 DOI: 10.1128/mcb.00159-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 05/01/2018] [Indexed: 02/06/2023] Open
Abstract
Accessibility of antigen receptor loci to RAG is correlated with the presence of H3K4me3, which binds to a plant homeodomain (PHD) in the RAG-2 subunit and promotes V(D)J recombination. A point mutation in the PHD, W453A, eliminates binding of H3K4me3 and impairs recombination. The debilitating effect of the W453A mutation is ameliorated by second-site mutations that locate an inhibitory domain in the interval from residues 352 through 405 of RAG-2. Disruption of the inhibitory domain stimulates V(D)J recombination within extrachromosomal substrates and at endogenous antigen receptor loci. Association of RAG-1 and RAG-2 with chromatin at the IgH locus in B cell progenitors is dependent on recognition of H3K4me3 by the PHD. Strikingly, disruption of the inhibitory domain permits association of RAG with the IgH locus in the absence of H3K4me3 binding. Thus, the inhibitory domain acts as a gate that prohibits RAG from accessing the IgH locus unless RAG-2 is engaged by H3K4me3.
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17
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Hewitt SL, Wong JB, Lee JH, Nishana M, Chen H, Coussens M, Arnal SM, Blumenberg LM, Roth DB, Paull TT, Skok JA. The Conserved ATM Kinase RAG2-S365 Phosphorylation Site Limits Cleavage Events in Individual Cells Independent of Any Repair Defect. Cell Rep 2018; 21:979-993. [PMID: 29069605 PMCID: PMC5662208 DOI: 10.1016/j.celrep.2017.09.084] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 08/23/2017] [Accepted: 09/25/2017] [Indexed: 12/03/2022] Open
Abstract
Many DNA lesions associated with lymphoid malignancies are linked to off-target cleavage by the RAG1/2 recombinase. However, off-target cleavage has mostly been analyzed in the context of DNA repair defects, confounding any mechanistic understanding of cleavage deregulation. We identified a conserved SQ phosphorylation site on RAG2 365 to 366 that is involved in feedback control of RAG cleavage. Mutation of serine 365 to a non-phosphorylatable alanine permits bi-allelic and bi-locus RAG-mediated breaks in the same cell, leading to reciprocal translocations. This phenomenon is analogous to the phenotype we described for ATM kinase inactivation. Here, we establish deregulated cleavage itself as a driver of chromosomal instability without the associated repair defect. Intriguingly, a RAG2-S365E phosphomimetic rescues the deregulated cleavage of ATM inactivation, reducing the incidence of reciprocal translocations. These data support a model in which feedback control of cleavage and maintenance of genome stability involves ATM-mediated phosphorylation of RAG2.
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Affiliation(s)
- Susannah L Hewitt
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Jason B Wong
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Ji-Hoon Lee
- Howard Hughes Medical Institute, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | | | - Hongxi Chen
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Marc Coussens
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA; Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Suzzette M Arnal
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Lili M Blumenberg
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - David B Roth
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tanya T Paull
- Howard Hughes Medical Institute, Department of Molecular Biosciences, Institute for Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
| | - Jane A Skok
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA.
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18
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Wu C, Dong Y, Zhao X, Zhang P, Zheng M, Zhang H, Li S, Jin Y, Ma Y, Ren H, Ji Y. RAG2 involves the Igκ locus demethylation during B cell development. Mol Immunol 2017. [PMID: 28641141 DOI: 10.1016/j.molimm.2017.06.026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The genes encoding the immunoglobulin κ light chain are assembled during B cell development by V(D)J recombination. For efficient rearrangement, the Igκ locus must undergo a series of epigenetic changes. One such epigenetic mark is DNA methylation. The mechanism that the Igκ locus is selectively demethylated at the pre-B cell stage has not previously been characterized. Here, we employed bisulfite DNA-modification assays to analyze the methylation status of the Igκ locus in primary pre-B cells from RAG-deficient mice with pre-rearranged Igh knock-in allele. We observed that the Igκ locus was hypermethylated in RAG2-deficient pre-B cells but hypomethylated in RAG1-deficient pre-B cells, indicating that wild-type (WT) RAG2 involves the Igκ locus demethylation in a RAG1-independent manner prior to rearrangement. We generated a series of RAG2 mutants between residue 350 and 383. We showed that these mutants mediated the Igκ rearrangement but failed to regulate the Igκ gene demethylation. We further analyzed that these mutants could increase RAG recombinase activity in vivo. We conclude that residues 350-383 region are responsible for endogenous Igκ locus demethylation at pre-B cells. We propose that WT RAG2 has an intrinsic function to regulate the Igκ locus demethylation.
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Affiliation(s)
- Caijun Wu
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Yanying Dong
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Xiaohui Zhao
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Ping Zhang
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Mingzhe Zheng
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Hua Zhang
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Shichang Li
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Yaofeng Jin
- Department of Pathology, the 2nd Affiliated hospital of Medical College, Xi'an Jiaotong University, Xi'an, Shaanxi, 710004, China
| | - Yunfeng Ma
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Huixun Ren
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China
| | - Yanhong Ji
- Department of Pathogenic Biology and Immunology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education of China, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, No.76 Yanta West Road, Xi'an, Shaanxi,710061, China.
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19
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Rommel PC, Oliveira TY, Nussenzweig MC, Robbiani DF. RAG1/2 induces genomic insertions by mobilizing DNA into RAG1/2-independent breaks. J Exp Med 2017; 214:815-831. [PMID: 28179379 PMCID: PMC5339680 DOI: 10.1084/jem.20161638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/09/2016] [Accepted: 12/12/2016] [Indexed: 11/23/2022] Open
Abstract
Rommel et al. reveal a novel RAG1/2-mediated insertion pathway, which has the potential to destabilize the lymphocyte genome and shares features with DNA insertions observed in human cancer. The RAG recombinase (RAG1/2) plays an essential role in adaptive immunity by mediating V(D)J recombination in developing lymphocytes. In contrast, aberrant RAG1/2 activity promotes lymphocyte malignancies by causing chromosomal translocations and DNA deletions at cancer genes. RAG1/2 can also induce genomic DNA insertions by transposition and trans-V(D)J recombination, but only few such putative events have been documented in vivo. We used next-generation sequencing techniques to examine chromosomal rearrangements in primary murine B cells and discovered that RAG1/2 causes aberrant insertions by releasing cleaved antibody gene fragments that subsequently reintegrate into DNA breaks induced on a heterologous chromosome. We confirmed that RAG1/2 also mobilizes genomic DNA into independent physiological breaks by identifying similar insertions in human lymphoma and leukemia. Our findings reveal a novel RAG1/2-mediated insertion pathway distinct from DNA transposition and trans-V(D)J recombination that destabilizes the genome and shares features with reported oncogenic DNA insertions.
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Affiliation(s)
- Philipp C Rommel
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065
| | - Thiago Y Oliveira
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065 .,Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065
| | - Davide F Robbiani
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065
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20
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Lescale C, Deriano L. The RAG recombinase: Beyond breaking. Mech Ageing Dev 2016; 165:3-9. [PMID: 27863852 DOI: 10.1016/j.mad.2016.11.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 11/04/2016] [Accepted: 11/11/2016] [Indexed: 11/17/2022]
Abstract
DNA double-strand breaks (DSBs) are commonly seen as lesions that threaten genome integrity and contribute to cancer and aging processes. However, in the context of antigen receptor gene assembly, known as V(D)J recombination, DSBs are obligatory intermediates that allow the establishment of genetic diversity and adaptive immunity. V(D)J recombination is initiated when the lymphoid-restricted recombination-activating genes RAG1 and RAG2 are expressed and form a site-specific endonuclease (the RAG nuclease or RAG recombinase). Here, we discuss the ability of the RAG nuclease to minimize the risks of genome disruption by coupling the breakage and repair steps of the V(D)J reaction. This implies that the RAG genes, derived from an ancient transposon, have undergone strong selective pressure to prohibit transposition in favor of promoting controlled DNA end joining in cis by the ubiquitous DNA damage response and DNA repair machineries. We also discuss the idea that, in addition to being essential for the rearrangement of antigen receptor genes, RAG-mediated DSBs could impact cellular processes and outcomes by affecting genetic and epigenetic programs.
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Affiliation(s)
- Chloé Lescale
- Department of Immunology and Department of Genomes and Genetics, Institut Pasteur, 75015 Paris, France
| | - Ludovic Deriano
- Department of Immunology and Department of Genomes and Genetics, Institut Pasteur, 75015 Paris, France.
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21
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Rodgers KK. Riches in RAGs: Revealing the V(D)J Recombinase through High-Resolution Structures. Trends Biochem Sci 2016; 42:72-84. [PMID: 27825771 DOI: 10.1016/j.tibs.2016.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/04/2016] [Accepted: 10/17/2016] [Indexed: 12/15/2022]
Abstract
Development of the adaptive immune system is dependent on V(D)J recombination, which forms functional antigen receptor genes through rearrangement of component gene segments. The V(D)J recombinase, comprising recombination-activating proteins RAG1 and RAG2, guides the initial DNA cleavage events to the recombination signal sequence (RSS), which flanks each gene segment. Although the enzymatic steps for RAG-mediated endonucleolytic activity were established over two decades ago, only recently have high-resolution structural studies of the catalytically active core regions of the RAG proteins shed light on conformational requirements for the reaction. While outstanding questions remain, we have a clearer picture of how RAG proteins function in generating the diverse repertoires of antigen receptors, the underlying foundation of the adaptive immune system.
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Affiliation(s)
- Karla K Rodgers
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73190, USA.
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22
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Meek K, Xu Y, Bailie C, Yu K, Neal JA. The ATM Kinase Restrains Joining of Both VDJ Signal and Coding Ends. THE JOURNAL OF IMMUNOLOGY 2016; 197:3165-3174. [PMID: 27574300 DOI: 10.4049/jimmunol.1600597] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Accepted: 08/06/2016] [Indexed: 11/19/2022]
Abstract
The evidence that ATM affects resolution of RAG-induced DNA double-strand breaks is profuse and unequivocal; moreover, it is clear that the RAG complex itself cooperates (in an undetermined way) with ATM to facilitate repair of these double-strand breaks by the classical nonhomologous end-joining pathway. The mechanistic basis for the cooperation between ATM and the RAG complex has not been defined, although proposed models invoke ATM and RAG2's C terminus in maintaining the RAG postcleavage complex. In this study, we show that ATM reduces the rate of both coding and signal joining in a robust episomal assay; we suggest that this is the result of increased stability of the postcleavage complex. ATM's ability to inhibit VDJ joining requires its enzymatic activity. The noncore C termini of both RAG1 and RAG2 are also required for ATM's capacity to limit signal (but not coding) joining. Moreover, potential phosphorylation targets within the C terminus of RAG2 are also required for ATM's capacity to limit signal joining. These data suggest a model whereby the RAG signal end complex is stabilized by phosphorylation of RAG2 by ATM.
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Affiliation(s)
- Katheryn Meek
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; .,Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; and
| | - Yao Xu
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.,Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; and
| | - Caleb Bailie
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.,Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; and
| | - Kefei Yu
- Department of Microbiology and Molecular Genetics, College of Human Medicine, Michigan State University, East Lansing, MI 48824
| | - Jessica A Neal
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824.,Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; and
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23
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Neal JA, Xu Y, Abe M, Hendrickson E, Meek K. Restoration of ATM Expression in DNA-PKcs-Deficient Cells Inhibits Signal End Joining. THE JOURNAL OF IMMUNOLOGY 2016; 196:3032-42. [PMID: 26921311 DOI: 10.4049/jimmunol.1501654] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 01/26/2016] [Indexed: 11/19/2022]
Abstract
Unlike most DNA-dependent protein kinase, catalytic subunit (DNA-PKcs)-deficient mouse cell strains, we show in the present study that targeted deletion of DNA-PKcs in two different human cell lines abrogates VDJ signal end joining in episomal assays. Although the mechanism is not well defined, DNA-PKcs deficiency results in spontaneous reduction of ATM expression in many cultured cell lines (including those examined in this study) and in DNA-PKcs-deficient mice. We considered that varying loss of ATM expression might explain differences in signal end joining in different cell strains and animal models, and we investigated the impact of ATM and/or DNA-PKcs loss on VDJ recombination in cultured human and rodent cell strains. To our surprise, in DNA-PKcs-deficient mouse cell strains that are proficient in signal end joining, restoration of ATM expression markedly inhibits signal end joining. In contrast, in DNA-PKcs-deficient cells that are deficient in signal end joining, complete loss of ATM enhances signal (but not coding) joint formation. We propose that ATM facilitates restriction of signal ends to the classical nonhomologous end-joining pathway.
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Affiliation(s)
- Jessica A Neal
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824
| | - Yao Xu
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824
| | - Masumi Abe
- National Institute of Radiological Sciences, Chiba 263-8555, Japan; and
| | - Eric Hendrickson
- Department of Biochemistry, Molecular Biology and Biophysics, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Katheryn Meek
- Department of Microbiology and Molecular Genetics, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824; Department of Pathobiology and Diagnostic Investigation, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824;
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24
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Abstract
V(D)J recombination, the mechanism responsible for generating antigen receptor diversity, has the potential to generate aberrant DNA rearrangements in developing lymphocytes. Indeed, the recombinase has been implicated in several different kinds of errors leading to oncogenic transformation. Here we review the basic aspects of V(D)J recombination, mechanisms underlying aberrant DNA rearrangements, and the types of aberrant events uncovered in recent genomewide analyses of lymphoid neoplasms.
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25
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Lescale C, Abramowski V, Bedora-Faure M, Murigneux V, Vera G, Roth DB, Revy P, de Villartay JP, Deriano L. RAG2 and XLF/Cernunnos interplay reveals a novel role for the RAG complex in DNA repair. Nat Commun 2016; 7:10529. [PMID: 26833222 PMCID: PMC4740868 DOI: 10.1038/ncomms10529] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/22/2015] [Indexed: 12/22/2022] Open
Abstract
XRCC4-like factor (XLF) functions in classical non-homologous end-joining (cNHEJ) but is dispensable for the repair of DNA double-strand breaks (DSBs) generated during V(D)J recombination. A long-standing hypothesis proposes that, in addition to its canonical nuclease activity, the RAG1/2 proteins participate in the DNA repair phase of V(D)J recombination. Here we show that in the context of RAG2 lacking the C-terminus domain (Rag2c/c mice), XLF deficiency leads to a profound lymphopenia associated with a severe defect in V(D)J recombination and, in the absence of p53, increased genomic instability at V(D)J sites. In addition, Rag2c/cXLF−/−p53−/− mice develop aggressive pro-B cell lymphomas bearing complex chromosomal translocations and gene amplifications involving Igh and c-myc/pvt1 loci. Our results reveal an unanticipated functional interplay between the RAG complex and XLF in repairing RAG-induced DSBs and maintaining genome integrity during antigen receptor gene assembly. Antigen receptor diversity relies on careful DNA cleavage and repair. Here the authors identify a functional interplay between RAG2 and XLF during V(D)J recombination, revealing an important role for the RAG complex in repairing induced DNA double-strand breaks and maintaining genome integrity.
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Affiliation(s)
- Chloé Lescale
- Departments of Immunology and Genomes and Genetics, Institut Pasteur, CNRS-URA 1961, Paris 75015, France
| | - Vincent Abramowski
- Laboratory of Genome Dynamics in the Immune System, INSERM UMR1163, Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Marie Bedora-Faure
- Departments of Immunology and Genomes and Genetics, Institut Pasteur, CNRS-URA 1961, Paris 75015, France
| | - Valentine Murigneux
- Departments of Immunology and Genomes and Genetics, Institut Pasteur, CNRS-URA 1961, Paris 75015, France
| | - Gabriella Vera
- Laboratory of Genome Dynamics in the Immune System, INSERM UMR1163, Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - David B Roth
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Patrick Revy
- Laboratory of Genome Dynamics in the Immune System, INSERM UMR1163, Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Jean-Pierre de Villartay
- Laboratory of Genome Dynamics in the Immune System, INSERM UMR1163, Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Ludovic Deriano
- Departments of Immunology and Genomes and Genetics, Institut Pasteur, CNRS-URA 1961, Paris 75015, France
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Xu K, Liu H, Shi Z, Song G, Zhu X, Jiang Y, Zhou Z, Liu X. Disruption of the RAG2 zinc finger motif impairs protein stability and causes immunodeficiency. Eur J Immunol 2015; 46:1011-9. [PMID: 26692406 DOI: 10.1002/eji.201545896] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Revised: 11/18/2015] [Accepted: 12/15/2015] [Indexed: 12/28/2022]
Abstract
Although the RAG2 core domain is the minimal region required for V(D)J recombination, the noncore region also plays important roles in the regulation of recombination, and mutations in this region are often related to severe combined immunodeficiency. A complete understanding of the functions of the RAG2 noncore region and the potential contributions of its individual residues has not yet been achieved. Here, we show that the zinc finger motif within the noncore region of RAG2 is indispensable for maintaining the stability of the RAG2 protein. The zinc finger motif in the noncore region of RAG2 is highly conserved from zebrafish to humans. Knock-in mice carrying a zinc finger mutation (C478Y) exhibit decreased V(D)J recombination efficiency and serious impairment in T/B-cell development due to RAG2 instability. Further studies also reveal the importance of the zinc finger motif for RAG2 stability. Moreover, mice harboring a RAG2 noncore region mutation (N474S), which is located near C478 but is not zinc-binding, exhibit no impairment in either RAG2 stability or T/B-cell development. Taken together, our findings contribute to defining critical functions of the RAG2 zinc finger motif and provide insights into the relationships between the mutations within this motif and immunodeficiency diseases.
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Affiliation(s)
- Ke Xu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Haifeng Liu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Zhubing Shi
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Guangrong Song
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiaoyan Zhu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yuzhang Jiang
- Department of Medical Laboratory, Huaian First People's Hospital, Nanjing Medical University, Huaian, Jiangsu, China
| | - Zhaocai Zhou
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiaolong Liu
- State Key Laboratory of Cell Biology, CAS Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
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27
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Abstract
The modular, noncontiguous architecture of the antigen receptor genes necessitates their assembly through V(D)J recombination. This program of DNA breakage and rejoining occurs during early lymphocyte development, and depends on the RAG1 and RAG2 proteins, whose collaborative endonuclease activity targets specific DNA motifs enriched in the antigen receptor loci. This essential gene shuffling reaction requires lymphocytes to traverse several developmental stages wherein DNA breakage is tolerated, while minimizing the expense to overall genome integrity. Thus, RAG activity is subject to stringent temporal and spatial regulation. The RAG proteins themselves also contribute autoregulatory properties that coordinate their DNA cleavage activity with target chromatin structure, cell cycle status, and DNA repair pathways. Even so, lapses in regulatory restriction of RAG activity are apparent in the aberrant V(D)J recombination events that underlie many lymphomas. In this review, we discuss the current understanding of the RAG endonuclease, its widespread binding in the lymphocyte genome, its noncleavage activities that restrain its enzymatic potential, and the growing evidence of its evolution from an ancient transposase.
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28
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Relating sequence encoded information to form and function of intrinsically disordered proteins. Curr Opin Struct Biol 2015; 32:102-12. [PMID: 25863585 DOI: 10.1016/j.sbi.2015.03.008] [Citation(s) in RCA: 287] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 11/23/2022]
Abstract
Intrinsically disordered proteins (IDPs) showcase the importance of conformational plasticity and heterogeneity in protein function. We summarize recent advances that connect information encoded in IDP sequences to their conformational properties and functions. We focus on insights obtained through a combination of atomistic simulations and biophysical measurements that are synthesized into a coherent framework using polymer physics theories.
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29
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An autoregulatory mechanism imposes allosteric control on the V(D)J recombinase by histone H3 methylation. Cell Rep 2014; 10:29-38. [PMID: 25543141 DOI: 10.1016/j.celrep.2014.12.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Revised: 09/29/2014] [Accepted: 11/25/2014] [Indexed: 01/15/2023] Open
Abstract
V(D)J recombination is initiated by a specialized transposase consisting of the subunits RAG-1 and RAG-2. The susceptibility of gene segments to DNA cleavage by the V(D)J recombinase is correlated with epigenetic modifications characteristic of active chromatin, including trimethylation of histone H3 on lysine 4 (H3K4me3). Engagement of H3K4me3 by a plant homeodomain (PHD) in RAG-2 promotes recombination in vivo and stimulates DNA cleavage by RAG in vitro. We now show that H3K4me3 acts allosterically at the PHD finger to relieve autoinhibition imposed by a separate domain within RAG-2. Disruption of this autoinhibitory domain was associated with constitutive increases in recombination frequency, DNA cleavage activity, substrate binding affinity, and catalytic rate, thus mimicking the stimulatory effects of H3K4me3. Our observations support a model in which allosteric control of RAG is enforced by an autoinhibitory domain whose action is relieved by engagement of active chromatin.
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30
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Ghosh S, Hönscheid A, Schwarz K, Eirich K, Schindler D, Schönberger S, Speckmann C, Borkhardt A, Laws HJ. RAG1 deficiency with a shifting B cell phenotype and chromosomal instability. Clin Immunol 2014; 152:65-7. [DOI: 10.1016/j.clim.2014.02.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 02/07/2014] [Indexed: 10/25/2022]
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31
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Gigi V, Lewis S, Shestova O, Mijušković M, Deriano L, Meng W, Luning Prak ET, Roth DB. RAG2 mutants alter DSB repair pathway choice in vivo and illuminate the nature of 'alternative NHEJ'. Nucleic Acids Res 2014; 42:6352-64. [PMID: 24753404 PMCID: PMC4041462 DOI: 10.1093/nar/gku295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
DNA double-stranded breaks (DSBs) can be repaired by several mechanisms, including classical NHEJ (c-NHEJ) and a poorly defined, error-prone process termed alternative NHEJ (a-NHEJ). How cells choose between these alternatives to join physiologic DSBs remains unknown. Here, we show that deletion of RAG2's C-terminus allows a-NHEJ to repair RAG-mediated DSBs in developing lymphocytes from both c-NHEJ-proficient and c-NHEJ-deficient mice, demonstrating that the V(D)J recombinase influences repair pathway choice in vivo. Analysis of V(D)J junctions revealed that, contrary to expectation, junctional characteristics alone do not reliably distinguish between a-NHEJ and c-NHEJ. These data suggest that a-NHEJ is not necessarily mutagenic, and may be more prevalent than previously appreciated. Whole genome sequencing of a lymphoma arising in a p53−/− mouse bearing a C-terminal RAG2 truncation reveals evidence of a-NHEJ and also of aberrant recognition of DNA sequences resembling RAG recognition sites.
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Affiliation(s)
- Vered Gigi
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Susanna Lewis
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Olga Shestova
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Martina Mijušković
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ludovic Deriano
- Departments of Immunology and Genomes & Genetics, Institut Pasteur, CNRS-URA 1961, 75015 Paris, France
| | - Wenzhao Meng
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Eline T Luning Prak
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David B Roth
- Department of Pathology and Laboratory Medicine and Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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32
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Frit P, Barboule N, Yuan Y, Gomez D, Calsou P. Alternative end-joining pathway(s): bricolage at DNA breaks. DNA Repair (Amst) 2014; 17:81-97. [PMID: 24613763 DOI: 10.1016/j.dnarep.2014.02.007] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 02/01/2014] [Accepted: 02/10/2014] [Indexed: 10/25/2022]
Abstract
To cope with DNA double strand break (DSB) genotoxicity, cells have evolved two main repair pathways: homologous recombination which uses homologous DNA sequences as repair templates, and non-homologous Ku-dependent end-joining involving direct sealing of DSB ends by DNA ligase IV (Lig4). During the last two decades a third player most commonly named alternative end-joining (A-EJ) has emerged, which is defined as any Ku- or Lig4-independent end-joining process. A-EJ increasingly appears as a highly error-prone bricolage on DSBs and despite expanding exploration, it still escapes full characterization. In the present review, we discuss the mechanism and regulation of A-EJ as well as its biological relevance under physiological and pathological situations, with a particular emphasis on chromosomal instability and cancer. Whether or not it is a genuine DSB repair pathway, A-EJ is emerging as an important cellular process and understanding A-EJ will certainly be a major challenge for the coming years.
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Affiliation(s)
- Philippe Frit
- CNRS, IPBS (Institut de Pharmacologie et de Biologie Structurale), BP 64182, 205 route de Narbonne, 31077 Toulouse, Cedex4, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France; Equipe labellisée Ligue Nationale Contre le Cancer, France
| | - Nadia Barboule
- CNRS, IPBS (Institut de Pharmacologie et de Biologie Structurale), BP 64182, 205 route de Narbonne, 31077 Toulouse, Cedex4, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France; Equipe labellisée Ligue Nationale Contre le Cancer, France
| | - Ying Yuan
- CNRS, IPBS (Institut de Pharmacologie et de Biologie Structurale), BP 64182, 205 route de Narbonne, 31077 Toulouse, Cedex4, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France; Equipe labellisée Ligue Nationale Contre le Cancer, France
| | - Dennis Gomez
- CNRS, IPBS (Institut de Pharmacologie et de Biologie Structurale), BP 64182, 205 route de Narbonne, 31077 Toulouse, Cedex4, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France; Equipe labellisée Ligue Nationale Contre le Cancer, France
| | - Patrick Calsou
- CNRS, IPBS (Institut de Pharmacologie et de Biologie Structurale), BP 64182, 205 route de Narbonne, 31077 Toulouse, Cedex4, France; Université de Toulouse, UPS, IPBS, F-31077 Toulouse, France; Equipe labellisée Ligue Nationale Contre le Cancer, France.
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