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Yang X, Wang X, Lei L, Su Y, Zou Y, Liu H, Jiao A, Zhang C, Liu J, Li W, Ding R, Zhou X, Shi L, Zhang D, Sun C, Zhang B. Arid1a promotes thymocyte development through β-selection-dependent and β-selection-independent mechanisms. Immunology 2021; 165:402-413. [PMID: 34921692 DOI: 10.1111/imm.13440] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/15/2021] [Accepted: 12/15/2021] [Indexed: 01/16/2023] Open
Abstract
Early T-cell development from CD4- CD8- double-negative (DN) stage to CD4+ CD8+ double-positive (DP) stage in the thymus is regulated through multiple steps involving a batch of sequentially expressed factors. Our preliminary data and a recent report showed that AT-rich interaction domain 1A (Arid1a) is required for the transition from DN to DP stages, but the mechanism is not fully understood. In this study, we consolidated that conditional deletion of Arid1a in T-cell lineage intrinsically caused developmental blocks from DN3 to DN4 stages, as well as from DN4 to DP stages using both in vivo adoptive T-cell transfer model and in vitro culture system. The expression of intracellular TCRβ is significantly decreased in Arid1a-deficient DN4 cells compared with WT cells. OT1 transgenic TCR can rescue the defect in the transition from DN3 to DN4 stages, but not from DN to DP stages. Furthermore, we observed a comparable or stronger proliferation capacity accompanied by a significant increase in cell death in Arid1a-/- DP cells compared with that in WT controls. RNA-Seq analysis shows a significant enrichment of apoptotic pathway within differentially expressed genes between Arid1a-/- and WT DP cells, including the upregulation of Bim, Casp3 and Trp53 and the downregulation of Rorc, Bcl-XL and Mcl1. Therefore, our study reveals a novel mechanism that Arid1a controls early T-cell development by maintaining intracellular TCRβ expression-mediated β-selection and activating parallel cell survival pathways.
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Affiliation(s)
- Xiaofeng Yang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Xin Wang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Lei Lei
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Yanhong Su
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Yujing Zou
- Duke University Medical Center, Durham, North Carolina, USA
| | - Haiyan Liu
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Anjun Jiao
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Cangang Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Jun Liu
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Wenhua Li
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Renyi Ding
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Xiaobo Zhou
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Lin Shi
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Dan Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China
| | - Chenming Sun
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
| | - Baojun Zhang
- Department of Pathogenic Microbiology and Immunology, School of Basic Medical Sciences; Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, China.,Institute of Infection and Immunity, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, China.,Key Laboratory of Environment and Genes Related to Diseases (Xi'an Jiaotong University), Ministry of Education, Xi'an, China.,Xi'an Key Laboratory of Immune Related Diseases, Xi'an, China
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2
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Babushkina NP, Postrigan AE, Kucher AN. Involvement of Variants in the Genes Encoding BRCA1-Associated Genome Surveillance Complex (BASC) in the Development of Human Common Diseases. Mol Biol 2021. [DOI: 10.1134/s0026893321020047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Chen Y, Sun J, Ju Z, Wang ZQ, Li T. Nbs1-mediated DNA damage repair pathway regulates haematopoietic stem cell development and embryonic haematopoiesis. Cell Prolif 2021; 54:e12972. [PMID: 33586242 PMCID: PMC7941224 DOI: 10.1111/cpr.12972] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/27/2020] [Accepted: 12/07/2020] [Indexed: 12/16/2022] Open
Abstract
Objectives DNA damages pose threats to haematopoietic stem cells (HSC) maintenance and haematopoietic system homeostasis. Quiescent HSCs in adult mouse bone marrow are resistant to DNA damage, while human umbilical cord blood‐derived proliferative HSCs are prone to cell death upon ionizing radiation. Murine embryonic HSCs proliferate in foetal livers and divide symmetrically to generate HSC pool. How murine embryonic HSCs respond to DNA damages is not well‐defined. Materials and methods Mice models with DNA repair molecule Nbs1 or Nbs1/p53 specifically deleted in embryonic HSCs were generated. FACS analysis, in vitro and in vivo HSC differentiation assays, qPCR, immunofluorescence and Western blotting were used to delineate roles of Nbs1‐p53 signaling in HSCs and haematopoietic progenitors. Results Nbs1 deficiency results in persistent DNA breaks in embryonic HSCs, compromises embryonic HSC development and finally results in mouse perinatal lethality. The persistent DNA breaks in Nbs1 deficient embryonic HSCs render cell cycle arrest, while driving a higher rate of cell death in haematopoietic progenitors. Although Nbs1 deficiency promotes Atm‐Chk2‐p53 axis activation in HSCs and their progenies, ablation of p53 in Nbs1 deficient HSCs accelerates embryonic lethality. Conclusions Our study discloses that DNA double‐strand repair molecule Nbs1 is essential in embryonic HSC development and haematopoiesis. Persistent DNA damages result in distinct cell fate in HSCs and haematopoietic progenitors. Nbs1 null HSCs tend to be maintained through cell cycle arrest, while Nbs1 null haematopoietic progenitors commit cell death. The discrepancies are mediated possibly by different magnitude of p53 signaling.
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Affiliation(s)
- Yu Chen
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Jie Sun
- Jiangsu Hansoh Pharmaceutical Group Co., Ltd., Lianyungang, China
| | - Zhenyu Ju
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Zhao-Qi Wang
- Leibniz Institute on Aging - Fritz Lipmann Institute, Jena, Germany.,Faculty of Biology and Pharmacy, Friedrich-Schiller University of Jena, Jena, Germany
| | - Tangliang Li
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China.,State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,NHC Key Laboratory of Birth Defect for Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
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4
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Piatosa B, Wolska-Kuśnierz B, Tkaczyk K, Heropolitanska-Pliszka E, Grycuk U, Wakulinska A, Gregorek H. T Lymphocytes in Patients With Nijmegen Breakage Syndrome Demonstrate Features of Exhaustion and Senescence in Flow Cytometric Evaluation of Maturation Pathway. Front Immunol 2020; 11:1319. [PMID: 32695108 PMCID: PMC7338427 DOI: 10.3389/fimmu.2020.01319] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 05/26/2020] [Indexed: 01/10/2023] Open
Abstract
Patients with Nijmegen Breakage Syndrome (NBS) suffer from recurrent infections due to humoral and cellular immune deficiency. Despite low number of T lymphocytes and their maturation defect, the clinical manifestations of cell-mediated deficiency are not as severe as in case of patients with other types of combined immune deficiencies and similar T cell lymphopenia. In this study, multicolor flow cytometry was used for evaluation of peripheral T lymphocyte maturation according to the currently known differentiation pathway, in 46 patients with genetically confirmed NBS and 46 sex and age-matched controls. Evaluation of differential expression of CD27, CD31, CD45RA, CD95, and CD197 revealed existence of cell subsets so far not described in NBS patients. Although recent thymic emigrants and naïve T lymphocyte cell populations were significantly lower, the generation of antigen-primed T cells was similar or even greater in NBS patients than in healthy controls. Moreover, the senescent and exhausted T cell populations defined by expression of CD57, KLRG1, and PD1 were more numerous than in healthy people. Although this hypothesis needs further investigations, such properties might be related to an increased susceptibility to malignancy and milder clinical course than expected in view of T cell lymphopenia in patients with NBS.
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Affiliation(s)
- Barbara Piatosa
- Histocompatibility Laboratory, Children's Memorial Health Institute, Warsaw, Poland
| | | | - Katarzyna Tkaczyk
- Histocompatibility Laboratory, Children's Memorial Health Institute, Warsaw, Poland
| | | | - Urszula Grycuk
- Histocompatibility Laboratory, Children's Memorial Health Institute, Warsaw, Poland
| | - Anna Wakulinska
- Department of Oncology, Children's Memorial Health Institute, Warsaw, Poland
| | - Hanna Gregorek
- Department of Microbiology and Clinical Immunology, Children's Memorial Health Institute, Warsaw, Poland
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5
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An integrated transcriptional switch at the β-selection checkpoint determines T cell survival, development and leukaemogenesis. Biochem Soc Trans 2019; 47:1077-1089. [DOI: 10.1042/bst20180414] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/05/2019] [Accepted: 06/06/2019] [Indexed: 02/06/2023]
Abstract
Abstract
In T cell development, a pivotal decision-making stage, termed β-selection, integrates a TCRβ checkpoint to coordinate survival, proliferation and differentiation to an αβ T cell. Here, we review how transcriptional regulation coordinates fate determination in early T cell development to enable β-selection. Errors in this transcription control can trigger T cell acute lymphoblastic leukaemia. We describe how the β-selection checkpoint goes awry in leukaemic transformation.
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6
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Diao D, Wang H, Li T, Shi Z, Jin X, Sperka T, Zhu X, Zhang M, Yang F, Cong Y, Shen L, Zhan Q, Yan J, Song Z, Ju Z. Telomeric epigenetic response mediated by Gadd45a regulates stem cell aging and lifespan. EMBO Rep 2018; 19:embr.201745494. [PMID: 30126922 DOI: 10.15252/embr.201745494] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 07/26/2018] [Accepted: 07/27/2018] [Indexed: 12/17/2022] Open
Abstract
Progressive attrition of telomeres triggers DNA damage response (DDR) and limits the regenerative capacity of adult stem cells during mammalian aging. Intriguingly, telomere integrity is not only determined by telomere length but also by the epigenetic status of telomeric/sub-telomeric regions. However, the functional interplay between DDR induced by telomere shortening and epigenetic modifications in aging remains unclear. Here, we show that deletion of Gadd45a improves the maintenance and function of intestinal stem cells (ISCs) and prolongs lifespan of telomerase-deficient mice (G3Terc -/-). Mechanistically, Gadd45a facilitates the generation of a permissive chromatin state for DDR signaling by inducing base excision repair-dependent demethylation of CpG islands specifically at sub-telomeric regions of short telomeres. Deletion of Gadd45a promotes chromatin compaction in sub-telomeric regions and attenuates DDR initiation at short telomeres of G3Terc -/- ISCs. Treatment with a small molecule inhibitor of base excision repair reduces DDR and improves the maintenance and function of G3Terc -/- ISCs. Taken together, our study proposes a therapeutic approach to enhance stem cell function and prolong lifespan by targeting epigenetic modifiers.
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Affiliation(s)
- Daojun Diao
- Key Laboratory of Regenerative Medicine of Ministry of Education, Institute of Aging and Regenerative Medicine, Jinan University, Guangzhou, China
| | - Hu Wang
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Tangliang Li
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Zhencan Shi
- Key Laboratory of Regenerative Medicine of Ministry of Education, Institute of Aging and Regenerative Medicine, Jinan University, Guangzhou, China
| | | | - Tobias Sperka
- Leibniz Institute on Aging, Fritz Lipmann Institute (FLI), Jena, Germany
| | - Xudong Zhu
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Meimei Zhang
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Fan Yang
- Key Laboratory of Regenerative Medicine of Ministry of Education, Institute of Aging and Regenerative Medicine, Jinan University, Guangzhou, China
| | - Yusheng Cong
- Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Li Shen
- Life Sciences Institute, Zhejiang University, Hangzhou, China
| | - Qimin Zhan
- State Key Laboratory of Molecular Oncology and Cancer Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
| | - Jing Yan
- Zhejiang Hospital, Hangzhou, China
| | - Zhangfa Song
- Department of Colorectal Surgery, Sir Run Run Shaw Hospital affiliated to Zhejiang University, Hangzhou, China
| | - Zhenyu Ju
- Key Laboratory of Regenerative Medicine of Ministry of Education, Institute of Aging and Regenerative Medicine, Jinan University, Guangzhou, China .,Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, China
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7
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DNA Damage Response in Hematopoietic Stem Cell Ageing. GENOMICS PROTEOMICS & BIOINFORMATICS 2016; 14:147-154. [PMID: 27221660 PMCID: PMC4936660 DOI: 10.1016/j.gpb.2016.04.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 04/20/2016] [Accepted: 04/24/2016] [Indexed: 12/30/2022]
Abstract
Maintenance of tissue-specific stem cells is vital for organ homeostasis and organismal longevity. Hematopoietic stem cells (HSCs) are the most primitive cell type in the hematopoietic system. They divide asymmetrically and give rise to daughter cells with HSC identity (self-renewal) and progenitor progenies (differentiation), which further proliferate and differentiate into full hematopoietic lineages. Mammalian ageing process is accompanied with abnormalities in the HSC self-renewal and differentiation. Transcriptional changes and epigenetic modulations have been implicated as the key regulators in HSC ageing process. The DNA damage response (DDR) in the cells involves an orchestrated signaling pathway, consisting of cell cycle regulation, cell death and senescence, transcriptional regulation, as well as chromatin remodeling. Recent studies employing DNA repair-deficient mouse models indicate that DDR could intrinsically and extrinsically regulate HSC maintenance and play important roles in tissue homeostasis of the hematopoietic system. In this review, we summarize the current understanding of how the DDR determines the HSC fates and finally contributes to organismal ageing.
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8
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Thornton TM, Delgado P, Chen L, Salas B, Krementsov D, Fernandez M, Vernia S, Davis RJ, Heimann R, Teuscher C, Krangel MS, Ramiro AR, Rincón M. Inactivation of nuclear GSK3β by Ser(389) phosphorylation promotes lymphocyte fitness during DNA double-strand break response. Nat Commun 2016; 7:10553. [PMID: 26822034 PMCID: PMC4740185 DOI: 10.1038/ncomms10553] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Accepted: 12/28/2015] [Indexed: 12/16/2022] Open
Abstract
Variable, diversity and joining (V(D)J) recombination and immunoglobulin class switch recombination (CSR) are key processes in adaptive immune responses that naturally generate DNA double-strand breaks (DSBs) and trigger a DNA repair response. It is unclear whether this response is associated with distinct survival signals that protect T and B cells. Glycogen synthase kinase 3β (GSK3β) is a constitutively active kinase known to promote cell death. Here we show that phosphorylation of GSK3β on Ser389 by p38 MAPK (mitogen-activated protein kinase) is induced selectively by DSBs through ATM (ataxia telangiectasia mutated) as a unique mechanism to attenuate the activity of nuclear GSK3β and promote survival of cells undergoing DSBs. Inability to inactivate GSK3β through Ser389 phosphorylation in Ser389Ala knockin mice causes a decrease in the fitness of cells undergoing V(D)J recombination and CSR. Preselection-Tcrβ repertoire is impaired and antigen-specific IgG antibody responses following immunization are blunted in Ser389GSK3β knockin mice. Thus, GSK3β emerges as an important modulator of the adaptive immune response. Double stranded DNA breaks are generated during rearrangements of lymphocyte antigen receptors. Here the authors show that the DNA breaks induce phosphorylation of nuclear GSK3β at Ser389/Thr390, protecting the activated lymphocytes from necroptosis-mediated cell death.
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Affiliation(s)
- Tina M Thornton
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Pilar Delgado
- B Cell Biology Lab, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 328029, Spain
| | - Liang Chen
- Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Beatriz Salas
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Dimitry Krementsov
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Miriam Fernandez
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Santiago Vernia
- Program in Molecular Medicine, University of Massachusetts, Worcester, Massachusetts 01605, USA
| | - Roger J Davis
- Program in Molecular Medicine, University of Massachusetts, Worcester, Massachusetts 01605, USA.,Howard Hughes Medical Institute, Worcester, Massachusetts 01605, USA
| | - Ruth Heimann
- Department of Medicine/Radiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Cory Teuscher
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
| | - Michael S Krangel
- Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Almudena R Ramiro
- B Cell Biology Lab, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid 328029, Spain
| | - Mercedes Rincón
- Department of Medicine/Immunobiology, University of Vermont, Burlington, Vermont 05405, USA
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9
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Prochazkova J, Loizou JI. Programmed DNA breaks in lymphoid cells: repair mechanisms and consequences in human disease. Immunology 2016; 147:11-20. [PMID: 26455503 PMCID: PMC4988471 DOI: 10.1111/imm.12547] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/05/2015] [Accepted: 10/06/2015] [Indexed: 01/08/2023] Open
Abstract
In recent years, several novel congenital human disorders have been described with defects in lymphoid B-cell and T-cell functions that arise due to mutations in known and/or novel components of DNA repair and damage response pathways. Examples include impaired DNA double-strand break repair, as well as compromised DNA damage-induced signal transduction, including phosphorylation and ubiquitination. These disorders reinforce the importance of genome stability pathways in the development of lymphoid cells in humans. Furthermore, these conditions inform our knowledge of the biology of the mechanisms of genome stability and in some cases may provide potential routes to help exploit these pathways therapeutically. Here we review the mechanisms that repair programmed DNA lesions that occur during B-cell and T-cell development, as well as human diseases that arise through defects in these pathways.
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Affiliation(s)
- Jana Prochazkova
- CeMM Research Centre for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
| | - Joanna I. Loizou
- CeMM Research Centre for Molecular Medicine of the Austrian Academy of SciencesViennaAustria
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10
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Balestrini A, Nicolas L, Yang-Lott K, Guryanova OA, Levine RL, Bassing CH, Chaudhuri J, Petrini JHJ. Defining ATM-Independent Functions of the Mre11 Complex with a Novel Mouse Model. Mol Cancer Res 2015; 14:185-95. [PMID: 26538284 DOI: 10.1158/1541-7786.mcr-15-0281] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 08/25/2015] [Indexed: 01/09/2023]
Abstract
UNLABELLED The Mre11 complex (Mre11, Rad50, and Nbs1) occupies a central node of the DNA damage response (DDR) network and is required for ATM activation in response to DNA damage. Hypomorphic alleles of MRE11 and NBS1 confer embryonic lethality in ATM-deficient mice, indicating that the complex exerts ATM-independent functions that are essential when ATM is absent. To delineate those functions, a conditional ATM allele (ATM(flox)) was crossed to hypomorphic NBS1 mutants (Nbs1(ΔB/ΔB) mice). Nbs1(ΔB/ΔB) Atm(-/-) hematopoietic cells derived by crossing to vav(cre) were viable in vivo. Nbs1(ΔB/ΔB) Atm(-/-) (VAV) mice exhibited a pronounced defect in double-strand break repair and completely penetrant early onset lymphomagenesis. In addition to repair defects observed, fragile site instability was noted, indicating that the Mre11 complex promotes genome stability upon replication stress in vivo. The data suggest combined influences of the Mre11 complex on DNA repair, as well as the responses to DNA damage and DNA replication stress. IMPLICATIONS A novel mouse model was developed, by combining a vav(cre)-inducible ATM knockout mouse with an NBS1 hypomorphic mutation, to analyze ATM-independent functions of the Mre11 complex in vivo. These data show that the DNA repair, rather than DDR signaling functions of the complex, is acutely required in the context of ATM deficiency to suppress genome instability and lymphomagenesis.
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Affiliation(s)
- Alessia Balestrini
- Molecular Biology Program, Sloan-Kettering Institute, New York, New York
| | - Laura Nicolas
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Katherine Yang-Lott
- Department of Pathology and Laboratory Medicine, Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. Abramson Family Cancer Research Institute, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Olga A Guryanova
- Human Oncology and Pathogenesis Program, Leukemia Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Ross L Levine
- Human Oncology and Pathogenesis Program, Leukemia Service, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York
| | - Craig H Bassing
- Department of Pathology and Laboratory Medicine, Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania. Abramson Family Cancer Research Institute, Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jayanta Chaudhuri
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, New York
| | - John H J Petrini
- Molecular Biology Program, Sloan-Kettering Institute, New York, New York.
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11
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Prochazkova J, Sakaguchi S, Owusu M, Mazouzi A, Wiedner M, Velimezi G, Moder M, Turchinovich G, Hladik A, Gurnhofer E, Hayday A, Behrens A, Knapp S, Kenner L, Ellmeier W, Loizou JI. DNA Repair Cofactors ATMIN and NBS1 Are Required to Suppress T Cell Activation. PLoS Genet 2015; 11:e1005645. [PMID: 26544571 PMCID: PMC4636180 DOI: 10.1371/journal.pgen.1005645] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Accepted: 10/12/2015] [Indexed: 12/11/2022] Open
Abstract
Proper development of the immune system is an intricate process dependent on many factors, including an intact DNA damage response. The DNA double-strand break signaling kinase ATM and its cofactor NBS1 are required during T cell development and for the maintenance of genomic stability. The role of a second ATM cofactor, ATMIN (also known as ASCIZ) in T cells is much less clear, and whether ATMIN and NBS1 function in synergy in T cells is unknown. Here, we investigate the roles of ATMIN and NBS1, either alone or in combination, using murine models. We show loss of NBS1 led to a developmental block at the double-positive stage of T cell development, as well as reduced TCRα recombination, that was unexpectedly neither exacerbated nor alleviated by concomitant loss of ATMIN. In contrast, loss of both ATMIN and NBS1 enhanced DNA damage that drove spontaneous peripheral T cell hyperactivation, proliferation as well as excessive production of proinflammatory cytokines and chemokines, leading to a highly inflammatory environment. Intriguingly, the disease causing T cells were largely proficient for both ATMIN and NBS1. In vivo this resulted in severe intestinal inflammation, colitis and premature death. Our findings reveal a novel model for an intestinal bowel disease phenotype that occurs upon combined loss of the DNA repair cofactors ATMIN and NBS1.
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Affiliation(s)
- Jana Prochazkova
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Shinya Sakaguchi
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Michel Owusu
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Abdelghani Mazouzi
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Marc Wiedner
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Georgia Velimezi
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Martin Moder
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Gleb Turchinovich
- London Research Institute, Cancer Research UK, London, United Kingdom
| | - Anastasiya Hladik
- Department of Medicine I, Laboratory of Infection Biology, Medical University of Vienna, Vienna, Austria
| | - Elisabeth Gurnhofer
- Clinical Institute for Pathology, Medical University Vienna, Vienna, Austria
| | - Adrian Hayday
- London Research Institute, Cancer Research UK, London, United Kingdom
| | - Axel Behrens
- London Research Institute, Cancer Research UK, London, United Kingdom
| | - Sylvia Knapp
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
- Department of Medicine I, Laboratory of Infection Biology, Medical University of Vienna, Vienna, Austria
| | - Lukas Kenner
- Clinical Institute for Pathology, Medical University Vienna, Vienna, Austria
| | - Wilfried Ellmeier
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Vienna, Austria
| | - Joanna I. Loizou
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
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12
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Abstract
The field of anatomic pathology has changed significantly over the last decades and, as a result of the technological developments in molecular pathology and genetics, has had increasing pressures put on it to become quantitative and to provide more information about protein expression on a cellular level in tissue sections. Multispectral imaging (MSI) has a long history as an advanced imaging modality and has been used for over a decade now in pathology to improve quantitative accuracy, enable the analysis of multicolor immunohistochemistry, and drastically reduce the impact of contrast-robbing tissue autofluorescence common in formalin-fixed, paraffin-embedded tissues. When combined with advanced software for the automated segmentation of different tissue morphologies (eg, tumor vs stroma) and cellular and subcellular segmentation, MSI can enable the per-cell quantitation of many markers simultaneously. This article covers the role that MSI has played in anatomic pathology in the analysis of formalin-fixed, paraffin-embedded tissue sections, discusses the technological aspects of why MSI has been adopted, and provides a review of the literature of the application of MSI in anatomic pathology.
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13
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Wang JQ, Chen JH, Chen YC, Chen MY, Hsieh CY, Teng SC, Wu KJ. Interaction between NBS1 and the mTOR/Rictor/SIN1 complex through specific domains. PLoS One 2013; 8:e65586. [PMID: 23762398 PMCID: PMC3675082 DOI: 10.1371/journal.pone.0065586] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 04/26/2013] [Indexed: 11/24/2022] Open
Abstract
Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome. The NBS gene product, NBS1 (p95 or nibrin), is a part of the Mre11-Rad50-NBS1 complex. SIN1 is a component of the mTOR/Rictor/SIN1 complex mediating the activation of Akt. Here we show that NBS1 interacted with mTOR, Rictor, and SIN1. The specific domains of mTOR, Rictor, or SIN1 interacted with the internal domain (a.a. 221-402) of NBS1. Sucrose density gradient showed that NBS1 was located in the same fractions as the mTOR/Rictor/SIN1 complex. Knockdown of NBS1 decreased the levels of phosphorylated Akt and its downstream targets. Ionizing radiation (IR) increased the NBS1 levels and activated Akt activity. These results demonstrate that NBS1 interacts with the mTOR/Rictor/SIN1 complex through the a.a. 221–402 domain and contributes to the activation of Akt activity.
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Affiliation(s)
- Jian-Qiu Wang
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
- Institute of Aging Research, Department of Basic Medical Science, School of Medicine, Hangzhou Normal University, Hangzhou, China
| | - Jian-Hong Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Chung Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Mei-Yu Chen
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Chia-Ying Hsieh
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
| | - Shu-Chun Teng
- Institute of Microbiology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Kou-Juey Wu
- Institute of Biochemistry and Molecular Biology, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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14
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Conti F, Ghigo E. PC3 (BTG2/TIS21) possible role in chromosome instability syndromes. Med Hypotheses 2013; 81:82-5. [PMID: 23639285 DOI: 10.1016/j.mehy.2013.03.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 03/12/2013] [Accepted: 03/25/2013] [Indexed: 11/18/2022]
Abstract
Chromosome instability syndromes (CIS) are autosomal recessive genetic disorders associated with defects in cell cycle regulation following DNA damage. Although most of the proteins involved in these syndromes have been identified as part of the MRN complex, little is known about their physiological functions and their interactions with other molecules that might explain the wide clinical presentation found in CIS patients. Here we discuss several observations suggesting that PC3 (BTG2/TIS21) - a protein involved in G1-S checkpoint progression control - might play a role in these pathologies.
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Affiliation(s)
- Filippo Conti
- Equipe Infections, Genre et Grossesse, URMITE-IRD198, CNRS UMR7278, INSERM U1095, Faculté de Médecine, 27 boulevard Jean Moulin, 13385 Marseille Cedex 05, France.
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15
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Abstract
Developing lymphocytes must assemble antigen receptor genes encoding the B cell and T cell receptors. This process is executed by the V(D)J recombination reaction, which can be divided into DNA cleavage and DNA joining steps. The former is carried out by a lymphocyte-specific RAG endonuclease, which mediates DNA cleavage at two recombining gene segments and their flanking RAG recognition sequences. RAG cleavage generates four broken DNA ends that are repaired by nonhomologous end joining forming coding and signal joints. On rare occasions, these DNA ends may join aberrantly forming chromosomal lesions such as translocations, deletions and inversions that have the potential to cause cellular transformation and lymphoid tumors. We discuss the activation of DNA damage responses by RAG-induced DSBs focusing on the component pathways that promote their normal repair and guard against their aberrant resolution. Moreover, we discuss how this DNA damage response impacts processes important for lymphocyte development.
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Affiliation(s)
- Beth A Helmink
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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16
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Li T, Wang ZQ. Point mutation at the Nbs1 Threonine 278 site does not affect mouse development, but compromises the Chk2 and Smc1 phosphorylation after DNA damage. Mech Ageing Dev 2011; 132:382-8. [PMID: 21664921 DOI: 10.1016/j.mad.2011.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 05/13/2011] [Accepted: 05/21/2011] [Indexed: 11/28/2022]
Abstract
NBS1, mutated in Nijmegen breakage syndrome (NBS), senses the DNA double strand breaks (DSBs) and initiates the DNA damage response (DDR) by activating ATM kinase. Meanwhile, NBS1 is phosphorylated by ATM at Serine 278 and Serine 343 and thereby assists the activation of the ATM downstream targets. To study the physiological function of the Nbs1 phosphorylation, we have knocked in a point mutation in the moue genome that results in the replacement of Threonine 278 (equivalent to the human Serine 278) by Alanine. The Nbs1(T278A) knock-in mice develop normally and show no gross defects. The mutation of this phosphorylation site does not affect the proliferation or genomic stability. Ionizing radiation (IR) of primary Nbs1(T278A) MEFs reveals no obvious defects in the Chk2 phosphorylation at 1Gy, but a delayed phosphorylation of Chk2 and Smc1 only at intermediate (4.5Gy) and high (10Gy) doses, respectively. In contrast to Serine 343 mutant, Threonine 278 mutation has no effect on the HU-induced ATR-Chk1 activation. Our study thus shows that Nbs1 phosphorylation at the Threonine 278 is dispensable for mouse development and plays a differential function in assisting the DDR of downstream effectors in vivo, depending on the doses of DNA damage.
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Affiliation(s)
- Tangliang Li
- Leibniz Institute for Age Research - Fritz Lipmann Institute, Jena, Germany
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17
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Loizou J, Sancho R, Kanu N, Bolland D, Yang F, Rada C, Corcoran A, Behrens A. ATMIN is required for maintenance of genomic stability and suppression of B cell lymphoma. Cancer Cell 2011; 19:587-600. [PMID: 21575860 PMCID: PMC4452547 DOI: 10.1016/j.ccr.2011.03.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Revised: 01/05/2011] [Accepted: 03/28/2011] [Indexed: 12/03/2022]
Abstract
Defective V(D)J rearrangement of immunoglobulin heavy or light chain (IgH or IgL) or class switch recombination (CSR) can initiate chromosomal translocations. The DNA-damage kinase ATM is required for the suppression of chromosomal translocations but ATM regulation is incompletely understood. Here, we show that mice lacking the ATM cofactor ATMIN in B cells (ATMIN(ΔB/ΔB)) have impaired ATM signaling and develop B cell lymphomas. Notably, ATMIN(ΔB/ΔB) cells exhibited defective peripheral V(D)J rearrangement and CSR, resulting in translocations involving the Igh and Igl loci, indicating that ATMIN is required for efficient repair of DNA breaks generated during somatic recombination. Thus, our results identify a role for ATMIN in regulating the maintenance of genomic stability and tumor suppression in B cells.
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MESH Headings
- Animals
- Antigens, CD19/genetics
- Antigens, CD19/metabolism
- Ataxia Telangiectasia Mutated Proteins
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Cycle Proteins/metabolism
- Cells, Cultured
- DNA Breaks
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Neoplastic
- Genes, Immunoglobulin Heavy Chain
- Genes, Immunoglobulin Light Chain
- Genomic Instability
- Immunoglobulin Class Switching
- Lymphoma, B-Cell/genetics
- Lymphoma, B-Cell/immunology
- Lymphoma, B-Cell/metabolism
- Lymphoma, B-Cell/pathology
- Lymphoma, B-Cell/prevention & control
- Mice
- Mice, Inbred ICR
- Mice, Knockout
- Mice, Nude
- Nuclear Proteins/deficiency
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Protein Serine-Threonine Kinases/metabolism
- Recombination, Genetic
- Signal Transduction
- Time Factors
- Transcription Factors
- Tumor Suppressor Proteins/deficiency
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/metabolism
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Affiliation(s)
- Joanna I. Loizou
- Mammalian Genetics Lab, Cancer Research UK, London Research Institute, 44, Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Rocio Sancho
- Mammalian Genetics Lab, Cancer Research UK, London Research Institute, 44, Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Nnennaya Kanu
- Mammalian Genetics Lab, Cancer Research UK, London Research Institute, 44, Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Daniel J. Bolland
- The Babraham Institute, Laboratory of Chromatin and Gene Expression, Cambridge CB22 3AT, UK
| | - Fengtang Yang
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Cristina Rada
- Medical Research Council Laboratory of Molecular Biology, Hills Road, Cambridge CB2 0QH, UK
| | - Anne E. Corcoran
- The Babraham Institute, Laboratory of Chromatin and Gene Expression, Cambridge CB22 3AT, UK
| | - Axel Behrens
- Mammalian Genetics Lab, Cancer Research UK, London Research Institute, 44, Lincoln's Inn Fields, London WC2A 3LY, UK
- Corresponding author
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18
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van Zelm MC, van der Burg M, Langerak AW, van Dongen JJM. PID comes full circle: applications of V(D)J recombination excision circles in research, diagnostics and newborn screening of primary immunodeficiency disorders. Front Immunol 2011; 2:12. [PMID: 22566803 PMCID: PMC3342366 DOI: 10.3389/fimmu.2011.00012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2011] [Accepted: 04/20/2011] [Indexed: 12/21/2022] Open
Abstract
The vast majority of patients suffering from a primary immunodeficiency (PID) have defects in their T- and/or B-cell compartments. Despite advances in molecular diagnostics, in many patients no underlying genetic defect has been identified. B- and T-lymphocytes are unique in their ability to create a receptor by genomic rearrangement of their antigen receptor genes via V(D)J recombination. During this process, stable circular excision products are formed that do not replicate when the cell proliferates. Excision circles can be reliably quantified using real-time quantitative (RQ-)PCR techniques. Frequently occurring δREC-ψJα T-cell receptor excision circles (TRECs) have been used to assess thymic output and intronRSS-Kde recombination excision circles (KREC) to quantify B-cell replication history. In this perspective, we describe how TRECs and KRECs are formed during precursor - T- and B-cell differentiation, respectively. Furthermore, we discuss new insights obtained with TRECs and KRECs and specifically how these excision circles can be applied to support therapy monitoring, patient classification and newborn screening of PID.
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Affiliation(s)
- Menno C van Zelm
- Department of Immunology, Erasmus MC, University Medical Center Rotterdam, Netherlands.
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19
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Abstract
The maintenance of genome stability depends on the DNA damage response (DDR), which is a functional network comprising signal transduction, cell cycle regulation and DNA repair. The metabolism of DNA double-strand breaks governed by the DDR is important for preventing genomic alterations and sporadic cancers, and hereditary defects in this response cause debilitating human pathologies, including developmental defects and cancer. The MRE11 complex, composed of the meiotic recombination 11 (MRE11), RAD50 and Nijmegen breakage syndrome 1 (NBS1; also known as nibrin) proteins is central to the DDR, and recent insights into its structure and function have been gained from in vitro structural analysis and studies of animal models in which the DDR response is deficient.
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Affiliation(s)
- Travis H Stracker
- Institute for Research in Biomedicine Barcelona, C/ Baldiri Reixac 10, 08028 Barcelona, Spain.
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