1
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Abukwaik R, Vera-Siguenza E, Tennant DA, Spill F. Interplay of p53 and XIAP protein dynamics orchestrates cell fate in response to chemotherapy. J Theor Biol 2023; 572:111562. [PMID: 37348784 DOI: 10.1016/j.jtbi.2023.111562] [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: 12/06/2022] [Revised: 04/06/2023] [Accepted: 06/16/2023] [Indexed: 06/24/2023]
Abstract
Chemotherapeutic drugs are used to treat almost all types of cancer, but the intended response, i.e., elimination, is often incomplete, with a subset of cancer cells resisting treatment. Two critical factors play a role in chemoresistance: the p53 tumour suppressor gene and the X-linked inhibitor of apoptosis (XIAP). These proteins have been shown to act synergistically to elicit cellular responses upon DNA damage induced by chemotherapy, yet, the mechanism is poorly understood. This study introduces a mathematical model characterising the apoptosis pathway activation by p53 before and after mitochondrial outer membrane permeabilisation upon treatment with the chemotherapy Doxorubicin (Dox). "In-silico" simulations show that the p53 dynamics change dose-dependently. Under medium to high doses of Dox, p53 concentration ultimately stabilises to a high level regardless of XIAP concentrations. However, caspase-3 activation may be triggered or not depending on the XIAP induction rate, ultimately determining whether the cell will perish or resist. Consequently, the model predicts that failure to activate apoptosis in some cancer cells expressing wild-type p53 might be due to heterogeneity between cells in upregulating the XIAP protein, rather than due to the p53 protein concentration. Our model suggests that the interplay of the p53 dynamics and the XIAP induction rate is critical to determine the cancer cells' therapeutic response.
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Affiliation(s)
- Roba Abukwaik
- Mathematics Department, Faculty of Science and Arts, King Abdulaziz University, Rabigh, Saudi Arabia; School of Mathematics, University of Birmingham, B15 2TS, United Kingdom.
| | - Elias Vera-Siguenza
- School of Mathematics, University of Birmingham, B15 2TS, United Kingdom; Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, B15 2TT, United Kingdom.
| | - Daniel A Tennant
- Institute of Metabolism and Systems Research, College of Medical and Dental Sciences, University of Birmingham, B15 2TT, United Kingdom
| | - Fabian Spill
- School of Mathematics, University of Birmingham, B15 2TS, United Kingdom.
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2
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Pozzi E, Giorgio E, Mancini C, Lo Buono N, Augeri S, Ferrero M, Di Gregorio E, Riberi E, Vinciguerra M, Nanetti L, Bianchi FT, Sassi MP, Costanzo V, Mariotti C, Funaro A, Cavalieri S, Brusco A. In vitro dexamethasone treatment does not induce alternative ATM transcripts in cells from Ataxia-Telangiectasia patients. Sci Rep 2020; 10:20182. [PMID: 33214630 PMCID: PMC7677391 DOI: 10.1038/s41598-020-77352-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 11/05/2020] [Indexed: 11/17/2022] Open
Abstract
Short term treatment with low doses of glucocorticoid analogues has been shown to ameliorate neurological symptoms in Ataxia–Telangiectasia (A–T), a rare autosomal recessive multisystem disease that mainly affects the cerebellum, immune system, and lungs. Molecular mechanisms underlying this clinical observation are unclear. We aimed at evaluating the effect of dexamethasone on the induction of alternative ATM transcripts (ATMdexa1). We showed that dexamethasone cannot induce an alternative ATM transcript in control and A–T lymphoblasts and primary fibroblasts, or in an ATM-knockout HeLa cell line. We also demonstrated that some of the reported readouts associated with ATMdexa1 are due to cellular artifacts and the direct induction of γH2AX by dexamethasone via DNA-PK. Finally, we suggest caution in interpreting dexamethasone effects in vitro for the results to be translated into a rational use of the drug in A–T patients.
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Affiliation(s)
- Elisa Pozzi
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Elisa Giorgio
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Cecilia Mancini
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Nicola Lo Buono
- Laboratory of Immune-Mediated Diseases, San Raffaele Diabetes Research Institute (DRI), 20132, Milan, Italy
| | - Stefania Augeri
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Marta Ferrero
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Eleonora Di Gregorio
- Unit of Medical Genetics, "Città Della Salute E Della Scienza" University Hospital, 10126, Turin, Italy
| | - Evelise Riberi
- Department of Public Health and Pediatrics, University of Torino, 10126, Turin, Italy
| | - Maria Vinciguerra
- DNA Metabolism Laboratory, FIRC Institute of Molecular Oncology (IFOM), 20139, Milan, Italy
| | - Lorenzo Nanetti
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico "Carlo Besta", 20133, Milan, Italy
| | - Federico Tommaso Bianchi
- Department of Molecular Biotechnologies and Health Sciences, Neuroscience Institute Cavalieri Ottolenghi, 10043, Orbassano, TO, Italy
| | - Maria Paola Sassi
- Istituto Nazionale di RIcerca Metrologica INRIM, 10135, Turin, Italy
| | - Vincenzo Costanzo
- DNA Metabolism Laboratory, FIRC Institute of Molecular Oncology (IFOM), 20139, Milan, Italy
| | - Caterina Mariotti
- Unit of Genetics of Neurodegenerative and Metabolic Diseases, Fondazione IRCCS Istituto Neurologico "Carlo Besta", 20133, Milan, Italy
| | - Ada Funaro
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Simona Cavalieri
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy
| | - Alfredo Brusco
- Department of Medical Sciences, University of Torino, via Santena 19, 10126, Turin, Italy. .,Unit of Medical Genetics, "Città Della Salute E Della Scienza" University Hospital, 10126, Turin, Italy.
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3
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Wappenschmidt B, Hauke J, Faust U, Niederacher D, Wiesmüller L, Schmidt G, Groß E, Gehrig A, Sutter C, Ramser J, Rump A, Arnold N, Meindl A. Criteria of the German Consortium for Hereditary Breast and Ovarian Cancer for the Classification of Germline Sequence Variants in Risk Genes for Hereditary Breast and Ovarian Cancer. Geburtshilfe Frauenheilkd 2020; 80:410-429. [PMID: 32322110 PMCID: PMC7174002 DOI: 10.1055/a-1110-0909] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 12/14/2022] Open
Abstract
More than ten years ago, the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC) set up a panel of experts (VUS Task Force) which was tasked with reviewing the classifications of genetic variants reported by individual centres of the GC-HBOC to the central database in Leipzig and reclassifying them, where necessary, based on the most recent data. When it evaluates variants, the VUS Task Force must arrive at a consensus. The resulting classifications are recorded in a central database where they serve as a basis for ensuring the consistent evaluation of previously known and newly identified variants in the different centres of the GC-HBOC. The standardised VUS evaluation by the VUS Task Force is a key element of the recall system which has also been set up by the GC-HBOC. The system will be used to pass on information to families monitored and managed by GC-HBOC centres in the event that previously classified variants are reclassified based on new information. The evaluation algorithm of the VUS Task Force was compiled using internationally established assessment methods (IARC, ACMG, ENIGMA) and is presented here together with the underlying evaluation criteria used to arrive at the classification decision using a flow chart. In addition, the characteristics and special features of specific individual risk genes associated with breast and/or ovarian cancer are discussed in separate subsections. The URLs of relevant databases have also been included together with extensive literature references to provide additional information and cover the scope and dynamism of the current state of knowledge on the evaluation of genetic variants. In future, if criteria are updated based on new information, the update will be published on the website of the GC-HBOC (
https://www.konsortium-familiaerer-brustkrebs.de/
).
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Affiliation(s)
- Barbara Wappenschmidt
- Zentrum familiärer Brust- und Eierstockkrebs, Universitätsklinikum Köln, Köln, Germany
| | - Jan Hauke
- Zentrum familiärer Brust- und Eierstockkrebs, Universitätsklinikum Köln, Köln, Germany
| | - Ulrike Faust
- Institut für Medizinische Genetik und Angewandte Genomik, Universität Tübingen, Tübingen, Germany
| | - Dieter Niederacher
- Klinik für Frauenheilkunde und Geburtshilfe, Universitätsklinikum Düsseldorf, Düsseldorf, Germany
| | - Lisa Wiesmüller
- Frauenklinik, Sektion Gynäkologische Onkologie, Uniklinik Ulm, Ulm, Germany
| | - Gunnar Schmidt
- Institut für Humangenetik, Medizinische Hochschule Hannover, Hannover, Germany
| | - Evi Groß
- Klinik und Poliklinik für Frauenheilkunde und Geburtshilfe, Klinikum der Universität München, Campus Großhadern, München, Germany
| | - Andrea Gehrig
- Institut für Humangenetik, Universität Würzburg, Würzburg, Germany
| | - Christian Sutter
- Institut für Humangenetik, Universität Heidelberg, Heidelberg, Germany
| | - Juliane Ramser
- Frauenklinik der Technischen Universität München, Klinikum rechts der Isar, München, Germany
| | - Andreas Rump
- Institut für klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Norbert Arnold
- Universitätsklinikum Kiel, Klinik für Gynäkologie und Geburtshilfe, Kiel, Germany.,Institut für Klinische Molekularbiologie, Universitätsklinikum Kiel, Kiel, Germany
| | - Alfons Meindl
- Klinik und Poliklinik für Frauenheilkunde und Geburtshilfe, Klinikum der Universität München, Campus Großhadern, München, Germany.,Frauenklinik der Technischen Universität München, Klinikum rechts der Isar, München, Germany
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4
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Venkatesh J, Sekhar SC, Cheriyan VT, Muthu M, Meister P, Levi E, Dzinic S, Gauld JW, Polin LA, Rishi AK. Antagonizing binding of cell cycle and apoptosis regulatory protein 1 (CARP-1) to the NEMO/IKKγ protein enhances the anticancer effect of chemotherapy. J Biol Chem 2020; 295:3532-3552. [PMID: 32024692 DOI: 10.1074/jbc.ra119.009898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 01/03/2020] [Indexed: 12/11/2022] Open
Abstract
NF-κB is a pro-inflammatory transcription factor that critically regulates immune responses and other distinct cellular pathways. However, many NF-κB-mediated pathways for cell survival and apoptosis signaling in cancer remain to be elucidated. Cell cycle and apoptosis regulatory protein 1 (CARP-1 or CCAR1) is a perinuclear phosphoprotein that regulates signaling induced by anticancer chemotherapy and growth factors. Although previous studies have reported that CARP-1 is a part of the NF-κB proteome, regulation of NF-κB signaling by CARP-1 and the molecular mechanism(s) involved are unclear. Here, we report that CARP-1 directly binds the NF-κB-activating kinase IκB kinase subunit γ (NEMO or NF-κB essential modulator) and regulates the chemotherapy-activated canonical NF-κB pathway. Importantly, blockade of NEMO-CARP-1 binding diminished NF-κB activation, indicated by reduced phosphorylation of its subunit p65/RelA by the chemotherapeutic agent adriamycin (ADR), but not NF-κB activation induced by tumor necrosis factor α (TNFα), interleukin (IL)-1β, or epidermal growth factor. High-throughput screening of a chemical library yielded a small molecule inhibitor of NEMO-CARP-1 binding, termed selective NF-κB inhibitor 1 (SNI)-1). We noted that SNI-1 enhances chemotherapy-dependent growth inhibition of a variety of cancer cells, including human triple-negative breast cancer (TNBC) and patient-derived TNBC cells in vitro, and attenuates chemotherapy-induced secretion of the pro-inflammatory cytokines TNFα, IL-1β, and IL-8. SNI-1 also enhanced ADR or cisplatin inhibition of murine TNBC tumors in vivo and reduced systemic levels of pro-inflammatory cytokines. We conclude that inhibition of NEMO-CARP-1 binding enhances responses of cancer cells to chemotherapy.
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Affiliation(s)
- Jaganathan Venkatesh
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201; Department of Oncology, Wayne State University, Detroit, Michigan 48201
| | - Sreeja C Sekhar
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201; Department of Oncology, Wayne State University, Detroit, Michigan 48201
| | - Vino T Cheriyan
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201; Department of Oncology, Wayne State University, Detroit, Michigan 48201
| | - Magesh Muthu
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201; Department of Oncology, Wayne State University, Detroit, Michigan 48201
| | - Paul Meister
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Edi Levi
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Department of Pathology, Wayne State University, Detroit, Michigan 48201
| | - Sijana Dzinic
- Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201
| | - James W Gauld
- Department of Chemistry and Biochemistry, University of Windsor, Windsor, Ontario N9B 3P4, Canada
| | - Lisa A Polin
- Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201
| | - Arun K Rishi
- John D. Dingell Veterans Affairs Medical Center, Wayne State University, Detroit, Michigan 48201; Karmanos Cancer Institute, Wayne State University, Detroit, Michigan 48201; Department of Oncology, Wayne State University, Detroit, Michigan 48201.
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5
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Eliaš J. Positive effect of Mdm2 on p53 expression explains excitability of p53 in response to DNA damage. J Theor Biol 2017; 418:94-104. [DOI: 10.1016/j.jtbi.2017.01.038] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 09/07/2016] [Accepted: 01/21/2017] [Indexed: 11/28/2022]
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6
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He C, Chiam KH, Chew LY. Comparison of cellular oscillations driven by noise or deterministic mechanisms under cell-size scaling. Phys Rev E 2016; 94:042425. [PMID: 27841613 DOI: 10.1103/physreve.94.042425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2016] [Indexed: 11/07/2022]
Abstract
Ultradian cycles are frequently observed in biological systems. They serve important roles in regulating, for example, cell fate and the development of the organism. Many mathematical models have been developed to analyze their behavior. Generally, these models can be classified into two classes: Deterministic models that generate oscillatory behavior by incorporating time delays or Hopf bifurcations, and stochastic models that generate oscillatory behavior by noise driven resonance. However, it is still unclear which of these two mechanisms applies to cellular oscillations. In this paper, we show through theoretical analysis and numerical simulation that we can distinguish which of these two mechanisms govern cellular oscillations, by measuring statistics of oscillation amplitudes for cells of different sizes. We found that, for oscillations driven deterministically, the normalized average amplitude is constant with respect to cell size, while the coefficient of variation of the amplitude scales with cell size with an exponent of -0.5. On the other hand, for oscillations driven stochastically, the coefficient of variation of the amplitude is constant with respect to cell size, while the normalized average amplitude scales with cell size with an exponent of -0.5. Our results provide a theoretical basis to discern whether a particular oscillatory behavior is governed by a deterministic or stochastic mechanism.
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Affiliation(s)
- Chong He
- School of Physical & Mathematical Science, Nanyang Technological University, 21 Nanyang Link, SPMS-PAP-04-04, Singapore 637371, Singapore
| | - Keng-Hwee Chiam
- Mechanobiology Institute, Level 10, T-Lab, National University of Singapore, Singapore 117411, Singapore.,A*STAR Bioinformatics Institute, 07-01 Matrix, Singapore 138671, Singapore
| | - Lock Yue Chew
- School of Physical & Mathematical Science, Nanyang Technological University, 21 Nanyang Link, SPMS-PAP-04-04, Singapore 637371, Singapore.,Complexity Institute, Nanyang Technological University, Singapore 637723, Singapore
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7
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Burgess JT, Bolderson E, Adams MN, Baird AM, Zhang SD, Gately KA, Umezawa K, O'Byrne KJ, Richard DJ. Activation and cleavage of SASH1 by caspase-3 mediates an apoptotic response. Cell Death Dis 2016; 7:e2469. [PMID: 27831555 PMCID: PMC5260870 DOI: 10.1038/cddis.2016.364] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 09/08/2016] [Accepted: 10/05/2016] [Indexed: 12/27/2022]
Abstract
Apoptosis is a highly regulated cellular process that functions to remove undesired cells from multicellular organisms. This pathway is often disrupted in cancer, providing tumours with a mechanism to avoid cell death and promote growth and survival. The putative tumour suppressor, SASH1 (SAM and SH3 domain containing protein 1), has been previously implicated in the regulation of apoptosis; however, the molecular role of SASH1 in this process is still unclear. In this study, we demonstrate that SASH1 is cleaved by caspase-3 following UVC-induced apoptosis. Proteolysis of SASH1 enables the C-terminal fragment to translocate from the cytoplasm to the nucleus where it associates with chromatin. The overexpression of wild-type SASH1 or a cleaved form of SASH1 representing amino acids 231-1247 leads to an increase in apoptosis. Conversely, mutation of the SASH1 cleavage site inhibits nuclear translocation and prevents the initiation of apoptosis. SASH1 cleavage is also required for the efficient translocation of the transcription factor nuclear factor-κB (NF-κB) to the nucleus. The use of the NF-κB inhibitor DHMEQ demonstrated that the effect of SASH1 on apoptosis was dependent on NF-κB, indicating a codependence between SASH1 and NF-κB for this process.
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Affiliation(s)
- Joshua T Burgess
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia
| | - Emma Bolderson
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia.,Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Mark N Adams
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia
| | - Anne-Marie Baird
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia
| | - Shu-Dong Zhang
- Northern Ireland Centre for Stratified Medicine, University of Ulster, C-TRIC Building, Altnagelvin Hospital Campus, Glenshane Road, Londonderry BT47 6SB, UK.,Center for Cancer Research and Cell Biology, Queen's University Belfast, Belfast, UK
| | - Kathy A Gately
- Thoracic Oncology Research Group, Institute of Molecular Medicine, Trinity College Dublin, St. James's Hospital, Dublin, Republic of Ireland
| | - Kazuo Umezawa
- Department of Molecular Target Medicine Screening, Aichi Medical University, Nagakute, Japan
| | - Kenneth J O'Byrne
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia.,Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, QLD 4102, Australia
| | - Derek J Richard
- Cancer and Ageing Program, Institute of Health and Biomedical Innovation at the Translational Research Institute (TRI), Queensland University of Technology (QUT) and Princess Alexandra Hospital, Level 6, Translational Research Institute, Brisbane, QLD, Australia.,Princess Alexandra Hospital, Ipswich Road, Woolloongabba, Brisbane, QLD 4102, Australia
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8
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Kanu N, Grönroos E, Martinez P, Burrell RA, Yi Goh X, Bartkova J, Maya-Mendoza A, Mistrík M, Rowan AJ, Patel H, Rabinowitz A, East P, Wilson G, Santos CR, McGranahan N, Gulati S, Gerlinger M, Birkbak NJ, Joshi T, Alexandrov LB, Stratton MR, Powles T, Matthews N, Bates PA, Stewart A, Szallasi Z, Larkin J, Bartek J, Swanton C. SETD2 loss-of-function promotes renal cancer branched evolution through replication stress and impaired DNA repair. Oncogene 2015; 34:5699-708. [PMID: 25728682 PMCID: PMC4660036 DOI: 10.1038/onc.2015.24] [Citation(s) in RCA: 128] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 12/29/2014] [Accepted: 01/06/2015] [Indexed: 12/13/2022]
Abstract
Defining mechanisms that generate intratumour heterogeneity and branched evolution may inspire novel therapeutic approaches to limit tumour diversity and adaptation. SETD2 (Su(var), Enhancer of zeste, Trithorax-domain containing 2) trimethylates histone-3 lysine-36 (H3K36me3) at sites of active transcription and is mutated in diverse tumour types, including clear cell renal carcinomas (ccRCCs). Distinct SETD2 mutations have been identified in spatially separated regions in ccRCC, indicative of intratumour heterogeneity. In this study, we have addressed the consequences of SETD2 loss-of-function through an integrated bioinformatics and functional genomics approach. We find that bi-allelic SETD2 aberrations are not associated with microsatellite instability in ccRCC. SETD2 depletion in ccRCC cells revealed aberrant and reduced nucleosome compaction and chromatin association of the key replication proteins minichromosome maintenance complex component (MCM7) and DNA polymerase δ hindering replication fork progression, and failure to load lens epithelium-derived growth factor and the Rad51 homologous recombination repair factor at DNA breaks. Consistent with these data, we observe chromosomal breakpoint locations are biased away from H3K36me3 sites in SETD2 wild-type ccRCCs relative to tumours with bi-allelic SETD2 aberrations and that H3K36me3-negative ccRCCs display elevated DNA damage in vivo. These data suggest a role for SETD2 in maintaining genome integrity through nucleosome stabilization, suppression of replication stress and the coordination of DNA repair.
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Affiliation(s)
- N Kanu
- UCL Cancer Institute, Paul O'Gorman Building, London, UK
| | - E Grönroos
- Cancer Research UK London Research Institute, London, UK
| | - P Martinez
- Cancer Research UK London Research Institute, London, UK
| | - R A Burrell
- Cancer Research UK London Research Institute, London, UK
| | - X Yi Goh
- Cancer Research UK London Research Institute, London, UK
| | - J Bartkova
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | - A Maya-Mendoza
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | - M Mistrík
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacky University, Olomouc, Czech Republic
| | - A J Rowan
- Cancer Research UK London Research Institute, London, UK
| | - H Patel
- Cancer Research UK London Research Institute, London, UK
| | - A Rabinowitz
- Cancer Research UK London Research Institute, London, UK
| | - P East
- Cancer Research UK London Research Institute, London, UK
| | - G Wilson
- Cancer Research UK London Research Institute, London, UK
| | - C R Santos
- Cancer Research UK London Research Institute, London, UK
| | - N McGranahan
- Cancer Research UK London Research Institute, London, UK
| | - S Gulati
- Cancer Research UK London Research Institute, London, UK
| | - M Gerlinger
- Cancer Research UK London Research Institute, London, UK
| | - N J Birkbak
- UCL Cancer Institute, Paul O'Gorman Building, London, UK
- Cancer Research UK London Research Institute, London, UK
- Department of Systems Biology, Center for Biological Sequence Analysis, Technical University of Denmark, Kongens Lyngby, Denmark
| | - T Joshi
- Department of Systems Biology, Center for Biological Sequence Analysis, Technical University of Denmark, Kongens Lyngby, Denmark
| | - L B Alexandrov
- Cancer Genome Project, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridgeshire, UK
| | - M R Stratton
- Cancer Genome Project, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridgeshire, UK
| | - T Powles
- Barts Cancer Institute, Experimental Cancer Medicine Centre, Queen Mary University of London, London, UK
| | - N Matthews
- Cancer Research UK London Research Institute, London, UK
| | - P A Bates
- Cancer Research UK London Research Institute, London, UK
| | - A Stewart
- Cancer Research UK London Research Institute, London, UK
| | - Z Szallasi
- Department of Systems Biology, Center for Biological Sequence Analysis, Technical University of Denmark, Kongens Lyngby, Denmark
- Children's Hospital Boston, Informatics—Enders 1506, Boston, MA, USA
| | - J Larkin
- Department of Medicine, The Royal Marsden Hospital, London, UK
| | - J Bartek
- Danish Cancer Society Research Center, Copenhagen, Denmark
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacky University, Olomouc, Czech Republic
| | - C Swanton
- UCL Cancer Institute, Paul O'Gorman Building, London, UK
- Cancer Research UK London Research Institute, London, UK
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9
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Lavin MF, Kozlov S, Gatei M, Kijas AW. ATM-Dependent Phosphorylation of All Three Members of the MRN Complex: From Sensor to Adaptor. Biomolecules 2015; 5:2877-902. [PMID: 26512707 PMCID: PMC4693261 DOI: 10.3390/biom5042877] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 10/14/2015] [Accepted: 10/16/2015] [Indexed: 11/16/2022] Open
Abstract
The recognition, signalling and repair of DNA double strand breaks (DSB) involves the participation of a multitude of proteins and post-translational events that ensure maintenance of genome integrity. Amongst the proteins involved are several which when mutated give rise to genetic disorders characterised by chromosomal abnormalities, cancer predisposition, neurodegeneration and other pathologies. ATM (mutated in ataxia-telangiectasia (A-T) and members of the Mre11/Rad50/Nbs1 (MRN complex) play key roles in this process. The MRN complex rapidly recognises and locates to DNA DSB where it acts to recruit and assist in ATM activation. ATM, in the company of several other DNA damage response proteins, in turn phosphorylates all three members of the MRN complex to initiate downstream signalling. While ATM has hundreds of substrates, members of the MRN complex play a pivotal role in mediating the downstream signalling events that give rise to cell cycle control, DNA repair and ultimately cell survival or apoptosis. Here we focus on the interplay between ATM and the MRN complex in initiating signaling of breaks and more specifically on the adaptor role of the MRN complex in mediating ATM signalling to downstream substrates to control different cellular processes.
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Affiliation(s)
- Martin F Lavin
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4029, Australia.
| | - Sergei Kozlov
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4029, Australia.
| | - Magtouf Gatei
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4029, Australia.
| | - Amanda W Kijas
- UQ Centre for Clinical Research, The University of Queensland, Brisbane, QLD 4029, Australia.
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10
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Hwang B, McCool K, Wan J, Wuerzberger-Davis SM, Young EWK, Choi EY, Cingolani G, Weaver BA, Miyamoto S. IPO3-mediated Nonclassical Nuclear Import of NF-κB Essential Modulator (NEMO) Drives DNA Damage-dependent NF-κB Activation. J Biol Chem 2015; 290:17967-17984. [PMID: 26060253 DOI: 10.1074/jbc.m115.645960] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Indexed: 11/06/2022] Open
Abstract
Activation of IκB kinase (IKK) and NF-κB by genotoxic stresses modulates apoptotic responses and production of inflammatory mediators, thereby contributing to therapy resistance and premature aging. We previously reported that genotoxic agents induce nuclear localization of NF-κB essential modulator (NEMO) via an undefined mechanism to arbitrate subsequent DNA damage-dependent IKK/NF-κB signaling. Here we show that a nonclassical nuclear import pathway via IPO3 (importin 3, transportin 2) mediates stress-induced NEMO nuclear translocation. We found putative nuclear localization signals in NEMO whose mutations disrupted stress-inducible nuclear translocation of NEMO and IKK/NF-κB activation in stably reconstituted NEMO-deficient cells. RNAi screening of both importin α and β family members, as well as co-immunoprecipitation analyses, revealed that a nonclassical importin β family member, IPO3, was the only importin that was able to associate with NEMO and whose reduced expression prevented genotoxic stress-induced NEMO nuclear translocation, IKK/NF-κB activation, and inflammatory cytokine transcription. Recombinant IPO3 interacted with recombinant NEMO but not the nuclear localization signal mutant version and induced nuclear import of NEMO in digitonin-permeabilized cells. We also provide evidence that NEMO is disengaged from IKK complex following genotoxic stress induction. Thus, the IPO3 nuclear import pathway is an early and crucial determinant of the IKK/NF-κB signaling arm of the mammalian DNA damage response.
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Affiliation(s)
- Byounghoon Hwang
- Department of Oncology, University of Wisconsin, Madison, Wisconsin
| | - Kevin McCool
- Department of Oncology, University of Wisconsin, Madison, Wisconsin; Molecular and Cellular Pharmacology Program, University of Wisconsin, Madison, Wisconsin
| | - Jun Wan
- Department of Cell and Regenerative Biology, University of Wisconsin, Madison, Wisconsin
| | - Shelly M Wuerzberger-Davis
- Department of Oncology, University of Wisconsin, Madison, Wisconsin; University of Wisconsin Carbone Cancer Center, University of Wisconsin, Madison, Wisconsin
| | - Edmond W K Young
- Department of Mechanical and Industrial Engineering and Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Eun Young Choi
- Department of Oncology, University of Wisconsin, Madison, Wisconsin
| | - Gino Cingolani
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Beth A Weaver
- Department of Cell and Regenerative Biology, University of Wisconsin, Madison, Wisconsin; University of Wisconsin Carbone Cancer Center, University of Wisconsin, Madison, Wisconsin
| | - Shigeki Miyamoto
- Department of Oncology, University of Wisconsin, Madison, Wisconsin; University of Wisconsin Carbone Cancer Center, University of Wisconsin, Madison, Wisconsin.
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11
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Herrup K, Chen J, Li J, Plummer MR. Ataxia-Telangiectasia and the Biology of Ataxia-Telangiectasia Mutated (ATM). Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00066-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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12
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Eliaš J, Dimitrio L, Clairambault J, Natalini R. The dynamics of p53 in single cells: physiologically based ODE and reaction-diffusion PDE models. Phys Biol 2014; 11:045001. [PMID: 25075792 DOI: 10.1088/1478-3975/11/4/045001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The intracellular signalling network of the p53 protein plays important roles in genome protection and the control of cell cycle phase transitions. Recently observed oscillatory behaviour in single cells under stress conditions has inspired several research groups to simulate and study the dynamics of the protein with the aim of gaining a proper understanding of the physiological meanings of the oscillations. We propose compartmental ODE and PDE models of p53 activation and regulation in single cells following DNA damage and we show that the p53 oscillations can be retrieved by plainly involving p53-Mdm2 and ATM-p53-Wip1 negative feedbacks, which are sufficient for oscillations experimentally, with no further need to introduce any delays into the protein responses and without considering additional positive feedback.
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Affiliation(s)
- Ján Eliaš
- UPMC, Laboratoire Jacques-Louis Lions, 4 Place Jussieu, F-75005 Paris, France & INRIA Paris-Rocquencourt, MAMBA project-team, Paris and Rocquencourt, France
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13
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Cremona CA, Behrens A. ATM signalling and cancer. Oncogene 2014; 33:3351-60. [PMID: 23851492 DOI: 10.1038/onc.2013.275] [Citation(s) in RCA: 152] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/17/2013] [Accepted: 05/20/2013] [Indexed: 12/12/2022]
Abstract
ATM, the protein kinase mutated in the rare human disease ataxia telangiectasia (A-T), has been the focus of intense scrutiny over the past two decades. Initially this was because of the unusual radiosensitive phenotype of cells from A-T patients, and latterly because investigating ATM signalling has yielded valuable insights into the DNA damage response, redox signalling and cancer. With the recent explosion in genomic data, ATM alterations have been revealed both in the germline as a predisposing factor for cancer and as somatic changes in tumours themselves. Here we review these findings, as well as advances in the understanding of ATM signalling mechanisms in cancer and ATM inhibition as a strategy for cancer treatment.
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Affiliation(s)
- C A Cremona
- Mammalian Genetics Lab, Cancer Research UK London Research Institute, London, UK
| | - A Behrens
- Mammalian Genetics Lab, Cancer Research UK London Research Institute, London, UK
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14
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Bolderson E, Petermann E, Croft L, Suraweera A, Pandita RK, Pandita TK, Helleday T, Khanna KK, Richard DJ. Human single-stranded DNA binding protein 1 (hSSB1/NABP2) is required for the stability and repair of stalled replication forks. Nucleic Acids Res 2014; 42:6326-36. [PMID: 24753408 PMCID: PMC4041449 DOI: 10.1093/nar/gku276] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aberrant DNA replication is a primary cause of mutations that are associated with pathological disorders including cancer. During DNA metabolism, the primary causes of replication fork stalling include secondary DNA structures, highly transcribed regions and damaged DNA. The restart of stalled replication forks is critical for the timely progression of the cell cycle and ultimately for the maintenance of genomic stability. Our previous work has implicated the single-stranded DNA binding protein, hSSB1/NABP2, in the repair of DNA double-strand breaks via homologous recombination. Here, we demonstrate that hSSB1 relocates to hydroxyurea (HU)-damaged replication forks where it is required for ATR and Chk1 activation and recruitment of Mre11 and Rad51. Consequently, hSSB1-depleted cells fail to repair and restart stalled replication forks. hSSB1 deficiency causes accumulation of DNA strand breaks and results in chromosome aberrations observed in mitosis, ultimately resulting in hSSB1 being required for survival to HU and camptothecin. Overall, our findings demonstrate the importance of hSSB1 in maintaining and repairing DNA replication forks and for overall genomic stability.
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Affiliation(s)
- Emma Bolderson
- Genome Stability Laboratory, Cancer and Ageing Research Program, Institute of Health and Biomedical Innovation, Translational Research Institute, Queensland University of Technology, Woolloongabba, Queensland, 4102, Australia
| | - Eva Petermann
- School of Cancer Sciences, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Laura Croft
- Genome Stability Laboratory, Cancer and Ageing Research Program, Institute of Health and Biomedical Innovation, Translational Research Institute, Queensland University of Technology, Woolloongabba, Queensland, 4102, Australia
| | - Amila Suraweera
- Genome Stability Laboratory, Cancer and Ageing Research Program, Institute of Health and Biomedical Innovation, Translational Research Institute, Queensland University of Technology, Woolloongabba, Queensland, 4102, Australia
| | - Raj K Pandita
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Tej K Pandita
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Thomas Helleday
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, S-171 21 Stockholm, Sweden
| | - Kum Kum Khanna
- Signal Transduction Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4029, Australia
| | - Derek J Richard
- Genome Stability Laboratory, Cancer and Ageing Research Program, Institute of Health and Biomedical Innovation, Translational Research Institute, Queensland University of Technology, Woolloongabba, Queensland, 4102, Australia
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15
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Eliaš J, Dimitrio L, Clairambault J, Natalini R. The p53 protein and its molecular network: modelling a missing link between DNA damage and cell fate. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1844:232-47. [PMID: 24113167 DOI: 10.1016/j.bbapap.2013.09.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 09/23/2013] [Accepted: 09/25/2013] [Indexed: 12/29/2022]
Abstract
Various molecular pharmacokinetic-pharmacodynamic (PK-PD) models have been proposed in the last decades to represent and predict drug effects in anticancer chemotherapies. Most of these models are cell population based since clearly measurable effects of drugs can be seen much more easily on populations of cells, healthy and tumour, than in individual cells. The actual targets of drugs are, however, cells themselves. The drugs in use either disrupt genome integrity by causing DNA strand breaks, and consequently initiate programmed cell death, or block cell proliferation mainly by inhibiting factors that enable cells to proceed from one cell cycle phase to the next through checkpoints in the cell division cycle. DNA damage caused by cytotoxic drugs (and also cytostatic drugs at high concentrations) activates, among others, the p53 protein-modulated signalling pathways that directly or indirectly force the cell to make a decision between survival and death. The paper aims to become the first-step in a larger scale enterprise that should bridge the gap between intracellular and population PK-PD models, providing oncologists with a rationale to predict and optimise the effects of anticancer drugs in the clinic. So far, it only sticks at describing p53 activation and regulation in single cells following their exposure to DNA damaging stress agents. We show that p53 oscillations that have been observed in individual cells can be reconstructed and predicted by compartmentalising cellular events occurring after DNA damage, either in the nucleus or in the cytoplasm, and by describing network interactions, using ordinary differential equations (ODEs), between the ATM, p53, Mdm2 and Wip1 proteins, in each compartment, nucleus or cytoplasm, and between the two compartments. This article is part of a Special Issue entitled: Computational Proteomics, Systems Biology & Clinical Implications.
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Affiliation(s)
- Ján Eliaš
- UPMC, Laboratoire Jacques-Louis Lions, 4 Place Jussieu, F-75005 Paris, France; INRIA Paris-Rocquencourt, Bang project-team, Paris and Rocquencourt, France.
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16
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Stankovic T, Skowronska A. The role of ATM mutations and 11q deletions in disease progression in chronic lymphocytic leukemia. Leuk Lymphoma 2013; 55:1227-39. [PMID: 23906020 DOI: 10.3109/10428194.2013.829919] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abstract ATM gene alteration is a frequent event in pathogenesis of chronic lymphocytic leukemia (CLL) and occurs as monoallelic loss in the form of 11q23 deletion, with and without mutation in the remaining ATM allele. ATM is a principal DNA damage response gene and biallelic ATM alterations lead to ATM functional loss and chemoresistance. The introduction of new therapies, such as intensive chemoimmunotherapy and inhibition of B-cell receptor (BCR) signaling, has changed clinical responses for the majority of CLL tumors including those with 11q deletion, but it remains to be determined whether these strategies can prevent clonal evolution of tumors with biallelic ATM alterations. In this review we discuss ATM function and the consequences of its loss during CLL pathogenesis, differences in clinical behavior of tumors with monoallelic and biallelic ATM alterations, and we outline possible approaches for targeting the ATM null CLL phenotype.
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Affiliation(s)
- Tatjana Stankovic
- School of Cancer Sciences, University of Birmingham , Birmingham , UK
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17
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Stracker TH, Roig I, Knobel PA, Marjanović M. The ATM signaling network in development and disease. Front Genet 2013; 4:37. [PMID: 23532176 PMCID: PMC3607076 DOI: 10.3389/fgene.2013.00037] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 03/04/2013] [Indexed: 12/15/2022] Open
Abstract
The DNA damage response (DDR) rapidly recognizes DNA lesions and initiates the appropriate cellular programs to maintain genome integrity. This includes the coordination of cell cycle checkpoints, transcription, translation, DNA repair, metabolism, and cell fate decisions, such as apoptosis or senescence (Jackson and Bartek, 2009). DNA double-strand breaks (DSBs) represent one of the most cytotoxic DNA lesions and defects in their metabolism underlie many human hereditary diseases characterized by genomic instability (Stracker and Petrini, 2011; McKinnon, 2012). Patients with hereditary defects in the DDR display defects in development, particularly affecting the central nervous system, the immune system and the germline, as well as aberrant metabolic regulation and cancer predisposition. Central to the DDR to DSBs is the ataxia-telangiectasia mutated (ATM) kinase, a master controller of signal transduction. Understanding how ATM signaling regulates various aspects of the DDR and its roles in vivo is critical for our understanding of human disease, its diagnosis and its treatment. This review will describe the general roles of ATM signaling and highlight some recent advances that have shed light on the diverse roles of ATM and related proteins in human disease.
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Affiliation(s)
- Travis H. Stracker
- Oncology Programme, Institute for Research in Biomedicine (IRB Barcelona)Barcelona, Spain
| | - Ignasi Roig
- Departament de Biologia Cellular, Fisiologia i Immunologia, Institut de Biotecnologia i Biomedicina, Universitat Autònoma de BarcelonBarcelona, Spain
| | - Philip A. Knobel
- Oncology Programme, Institute for Research in Biomedicine (IRB Barcelona)Barcelona, Spain
| | - Marko Marjanović
- Oncology Programme, Institute for Research in Biomedicine (IRB Barcelona)Barcelona, Spain
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18
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Davis AJ, Lee KJ, Chen DJ. The N-terminal region of the DNA-dependent protein kinase catalytic subunit is required for its DNA double-stranded break-mediated activation. J Biol Chem 2013; 288:7037-46. [PMID: 23322783 DOI: 10.1074/jbc.m112.434498] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
DNA-dependent protein kinase (DNA-PK) plays an essential role in the repair of DNA double-stranded breaks (DSBs) mediated by the nonhomologous end-joining pathway. DNA-PK is a holoenzyme consisting of a DNA-binding (Ku70/Ku80) and catalytic (DNA-PKcs) subunit. DNA-PKcs is a serine/threonine protein kinase that is recruited to DSBs via Ku70/80 and is activated once the kinase is bound to the DSB ends. In this study, two large, distinct fragments of DNA-PKcs, consisting of the N terminus (amino acids 1-2713), termed N-PKcs, and the C terminus (amino acids 2714-4128), termed C-PKcs, were produced to determine the role of each terminal region in regulating the activity of DNA-PKcs. N-PKcs but not C-PKcs interacts with the Ku-DNA complex and is required for the ability of DNA-PKcs to localize to DSBs. C-PKcs has increased basal kinase activity compared with DNA-PKcs, suggesting that the N-terminal region of DNA-PKcs keeps basal activity low. The kinase activity of C-PKcs is not stimulated by Ku70/80 and DNA, further supporting that the N-terminal region is required for binding to the Ku-DNA complex and full activation of kinase activity. Collectively, the results show the N-terminal region mediates the interaction between DNA-PKcs and the Ku-DNA complex and is required for its DSB-induced enzymatic activity.
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Affiliation(s)
- Anthony J Davis
- Division of Molecular Radiation Biology, Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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19
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Menotta M, Biagiotti S, Bianchi M, Chessa L, Magnani M. Dexamethasone partially rescues ataxia telangiectasia-mutated (ATM) deficiency in ataxia telangiectasia by promoting a shortened protein variant retaining kinase activity. J Biol Chem 2012; 287:41352-63. [PMID: 23055520 DOI: 10.1074/jbc.m112.344473] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ataxia telangiectasia (AT) is a rare genetic disease, still incurable, resulting from biallelic mutations in the ataxia telangiectasia-mutated (ATM) gene. Recently, short term treatment with glucocorticoid analogues improved neurological symptoms characteristic of this syndrome. Nevertheless, the molecular mechanism involved in glucocorticoid action in AT patients is not yet known. Here we describe, for the first time in mammalian cells, a short direct repeat-mediated noncanonical splicing event induced by dexamethasone, which leads to the skipping of mutations upstream of nucleotide residue 8450 of ATM coding sequence. The resulting transcript provides an alternative ORF translated in a new ATM variant with the complete kinase domain. This miniATM variant was also highlighted in lymphoblastoid cell lines from AT patients and was shown to be likely active. In conclusion, dexamethasone treatment may partly restore ATM activity in ataxia telangiectasia cells by a new molecular mechanism that overcomes most of the mutations so far described within this gene.
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Affiliation(s)
- Michele Menotta
- Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy.
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20
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Bolderson E, Savage KI, Mahen R, Pisupati V, Graham ME, Richard DJ, Robinson PJ, Venkitaraman AR, Khanna KK. Kruppel-associated Box (KRAB)-associated co-repressor (KAP-1) Ser-473 phosphorylation regulates heterochromatin protein 1β (HP1-β) mobilization and DNA repair in heterochromatin. J Biol Chem 2012; 287:28122-31. [PMID: 22715096 DOI: 10.1074/jbc.m112.368381] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The DNA damage response encompasses a complex series of signaling pathways that function to regulate and facilitate the repair of damaged DNA. Recent studies have shown that the repair of transcriptionally inactive chromatin, named heterochromatin, is dependent upon the phosphorylation of the co-repressor, Krüppel-associated box (KRAB) domain-associated protein (KAP-1), by the ataxia telangiectasia-mutated (ATM) kinase. Co-repressors, such as KAP-1, function to regulate the rigid structure of heterochromatin by recruiting histone-modifying enzymes, such HDAC1/2, SETDB1, and nucleosome-remodeling complexes such as CHD3. Here, we have characterized a phosphorylation site in the HP1-binding domain of KAP-1, Ser-473, which is phosphorylated by the cell cycle checkpoint kinase Chk2. Expression of a nonphosphorylatable S473A mutant conferred cellular sensitivity to DNA-damaging agents and led to defective repair of DNA double-strand breaks in heterochromatin. In addition, cells expressing S473A also displayed defective mobilization of the HP1-β chromodomain protein. The DNA repair defect observed in cells expressing S473A was alleviated by depletion of HP1-β, suggesting that phosphorylation of KAP-1 on Ser-473 promotes the mobilization of HP1-β from heterochromatin and subsequent DNA repair. These results suggest a novel mechanism of KAP-1-mediated chromatin restructuring via Chk2-regulated HP1-β exchange from heterochromatin, promoting DNA repair.
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Affiliation(s)
- Emma Bolderson
- Signal Transduction Laboratory, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
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21
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Tomimatsu N, Mukherjee B, Deland K, Kurimasa A, Bolderson E, Khanna KK, Burma S. Exo1 plays a major role in DNA end resection in humans and influences double-strand break repair and damage signaling decisions. DNA Repair (Amst) 2012; 11:441-8. [PMID: 22326273 DOI: 10.1016/j.dnarep.2012.01.006] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 12/28/2011] [Accepted: 01/09/2012] [Indexed: 02/03/2023]
Abstract
The resection of DNA double-strand breaks (DSBs) to generate ssDNA tails is a pivotal event in the cellular response to these breaks. In the two-step model of resection, primarily elucidated in yeast, initial resection by Mre11-CtIP is followed by extensive resection by two distinct pathways involving Exo1 or BLM/WRN-Dna2. However, resection pathways and their exact contributions in humans in vivo are not as clearly worked out as in yeast. Here, we examined the contribution of Exo1 to DNA end resection in humans in vivo in response to ionizing radiation (IR) and its relationship with other resection pathways (Mre11-CtIP or BLM/WRN). We find that Exo1 plays a predominant role in resection in human cells along with an alternate pathway dependent on WRN. While Mre11 and CtIP stimulate resection in human cells, they are not absolutely required for this process and Exo1 can function in resection even in the absence of Mre11-CtIP. Interestingly, the recruitment of Exo1 to DNA breaks appears to be inhibited by the NHEJ protein Ku80, and the higher level of resection that occurs upon siRNA-mediated depletion of Ku80 is dependent on Exo1. In addition, Exo1 may be regulated by 53BP1 and Brca1, and the restoration of resection in BRCA1-deficient cells upon depletion of 53BP1 is dependent on Exo1. Finally, we find that Exo1-mediated resection facilitates a transition from ATM- to ATR-mediated cell cycle checkpoint signaling. Our results identify Exo1 as a key mediator of DNA end resection and DSB repair and damage signaling decisions in human cells.
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Affiliation(s)
- Nozomi Tomimatsu
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, USA
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22
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Jacquemin V, Rieunier G, Jacob S, Bellanger D, d'Enghien CD, Laugé A, Stoppa-Lyonnet D, Stern MH. Underexpression and abnormal localization of ATM products in ataxia telangiectasia patients bearing ATM missense mutations. Eur J Hum Genet 2011; 20:305-12. [PMID: 22071889 DOI: 10.1038/ejhg.2011.196] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Ataxia telangiectasia (A-T) is a rare autosomal recessive disorder characterized by progressive cerebellar ataxia, oculocutaneous telangiectasia, immune defects and predisposition to malignancies. A-T is caused by biallelic inactivation of the ATM gene, in most cases by frameshift or nonsense mutations. More rarely, ATM missense mutations with unknown consequences on ATM function are found, making definitive diagnosis more challenging. In this study, a series of 15 missense mutations, including 11 not previously reported, were identified in 16 patients with clinical diagnosis of A-T belonging to 14 families and 1 patient with atypical clinical features. ATM function was evaluated in patient lymphoblastoid cell lines by measuring H2AX and KAP1 phosphorylation in response to ionizing radiation, confirming the A-T diagnosis for 16 cases. In accordance with previous studies, we showed that missense mutations associated with A-T often lead to ATM protein underexpression (15 out of 16 cases). In addition, we demonstrated that most missense mutations lead to an abnormal cytoplasmic localization of ATM, correlated with its decreased expression. This new finding highlights ATM mislocalization as a new mechanism of ATM dysfunction, which may lead to therapeutic strategies for missense mutation associated A-T.
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23
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Bhatti S, Kozlov S, Farooqi AA, Naqi A, Lavin M, Khanna KK. ATM protein kinase: the linchpin of cellular defenses to stress. Cell Mol Life Sci 2011; 68:2977-3006. [PMID: 21533982 PMCID: PMC11115042 DOI: 10.1007/s00018-011-0683-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 03/24/2011] [Accepted: 03/29/2011] [Indexed: 01/23/2023]
Abstract
ATM is the most significant molecule involved in monitoring the genomic integrity of the cell. Any damage done to DNA relentlessly challenges the cellular machinery involved in recognition, processing and repair of these insults. ATM kinase is activated early to detect and signal lesions in DNA, arrest the cell cycle, establish DNA repair signaling and faithfully restore the damaged chromatin. ATM activation plays an important role as a barrier to tumorigenesis, metabolic syndrome and neurodegeneration. Therefore, studies of ATM-dependent DNA damage signaling pathways hold promise for treatment of a variety of debilitating diseases through the development of new therapeutics capable of modulating cellular responses to stress. In this review, we have tried to untangle the complex web of ATM signaling pathways with the purpose of pinpointing multiple roles of ATM underlying the complex phenotypes observed in AT patients.
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Affiliation(s)
- Shahzad Bhatti
- Institute of Molecular Biology and Biotechnology, The University of Lahore, 1 Km Raiwind Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Sergei Kozlov
- Queensland Institute of Medical Research, QIMR, 300 Herston Rd, Herston, Brisbane, 4029 Australia
| | - Ammad Ahmad Farooqi
- Institute of Molecular Biology and Biotechnology, The University of Lahore, 1 Km Raiwind Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Ali Naqi
- Institute of Molecular Biology and Biotechnology, The University of Lahore, 1 Km Raiwind Road, Thokar Niaz Baig, Lahore, Pakistan
| | - Martin Lavin
- Queensland Institute of Medical Research, QIMR, 300 Herston Rd, Herston, Brisbane, 4029 Australia
| | - Kum Kum Khanna
- Queensland Institute of Medical Research, QIMR, 300 Herston Rd, Herston, Brisbane, 4029 Australia
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24
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Kozlov SV, Graham ME, Jakob B, Tobias F, Kijas AW, Tanuji M, Chen P, Robinson PJ, Taucher-Scholz G, Suzuki K, So S, Chen D, Lavin MF. Autophosphorylation and ATM activation: additional sites add to the complexity. J Biol Chem 2011; 286:9107-19. [PMID: 21149446 PMCID: PMC3059052 DOI: 10.1074/jbc.m110.204065] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2010] [Indexed: 12/18/2022] Open
Abstract
The recognition and signaling of DNA double strand breaks involves the participation of multiple proteins, including the protein kinase ATM (mutated in ataxia-telangiectasia). ATM kinase is activated in the vicinity of the break and is recruited to the break site by the Mre11-Rad50-Nbs1 complex, where it is fully activated. In human cells, the activation process involves autophosphorylation on three sites (Ser(367), Ser(1893), and Ser(1981)) and acetylation on Lys(3016). We now describe the identification of a new ATM phosphorylation site, Thr(P)(1885) and an additional autophosphorylation site, Ser(P)(2996), that is highly DNA damage-inducible. We also confirm that human and murine ATM share five identical phosphorylation sites. We targeted the ATM phosphorylation sites, Ser(367) and Ser(2996), for further study by generating phosphospecific antibodies against these sites and demonstrated that phosphorylation of both was rapidly induced by radiation. These phosphorylations were abolished by a specific inhibitor of ATM and were dependent on ATM and the Mre11-Rad50-Nbs1 complex. As found for Ser(P)(1981), ATM phosphorylated at Ser(367) and Ser(2996) localized to sites of DNA damage induced by radiation, but ATM recruitment was not dependent on phosphorylation at these sites. Phosphorylation at Ser(367) and Ser(2996) was functionally important because mutant forms of ATM were defective in correcting the S phase checkpoint defect and restoring radioresistance in ataxia-telangiectasia cells. These data provide further support for the importance of autophosphorylation in the activation and function of ATM in vivo.
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Affiliation(s)
- Sergei V. Kozlov
- From Radiation Biology and Oncology, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
| | - Mark E. Graham
- the Children's Medical Research Institute, University of Sydney, Westmead, New South Wales 2145, Australia
| | - Burkhard Jakob
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Biophysik, Planckstrasse 1, D-64291 Darmstadt, Germany
| | - Frank Tobias
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Biophysik, Planckstrasse 1, D-64291 Darmstadt, Germany
| | - Amanda W. Kijas
- From Radiation Biology and Oncology, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
| | - Marcel Tanuji
- From Radiation Biology and Oncology, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
| | - Philip Chen
- From Radiation Biology and Oncology, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
| | - Phillip J. Robinson
- the Children's Medical Research Institute, University of Sydney, Westmead, New South Wales 2145, Australia
| | - Gisela Taucher-Scholz
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Biophysik, Planckstrasse 1, D-64291 Darmstadt, Germany
| | - Keiji Suzuki
- the Department of Molecular Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | - Sairai So
- the University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
| | - David Chen
- the University of Texas Southwestern Medical Center, Dallas, Texas 75390, and
| | - Martin F. Lavin
- From Radiation Biology and Oncology, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
- the University of Queensland Centre for Clinical Research, Brisbane, Queensland 4029, Australia
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Ishikawa T, Kamei Y, Otozai S, Kim J, Sato A, Kuwahara Y, Tanaka M, Deguchi T, Inohara H, Tsujimura T, Todo T. High-resolution melting curve analysis for rapid detection of mutations in a Medaka TILLING library. BMC Mol Biol 2010; 11:70. [PMID: 20840787 PMCID: PMC2949603 DOI: 10.1186/1471-2199-11-70] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Accepted: 09/15/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND During the last two decades, DNA sequencing has led to the identification of numerous genes in key species; however, in most cases, their functions are still unknown. In this situation, reverse genetics is the most suitable method to assign function to a gene. TILLING (Targeting Induced Local Lesions IN Genomes) is a reverse-genetic strategy that combines random chemical mutagenesis with high-throughput discovery of the induced mutations in target genes. The method has been applied to a variety of plant and animal species. Screening of the induced mutations is the most important step in TILLING. Currently, direct sequencing or nuclease-mediated screening of heteroduplexes is widely used for detection of mutations in TILLING. Both methods are useful, but the costs are substantial and turnaround times are relatively long. Thus, there is a need for an alternative method that is of higher throughput and more cost effective. RESULTS In this study, we developed a high resolution melting (HRM) assay and evaluated its effectiveness for screening ENU-induced mutations in a medaka TILLING library. We had previously screened mutations in the p53 gene by direct sequencing. Therefore, we first tested the efficiency of the HRM assay by screening mutations in p53, which indicated that the HRM assay is as useful as direct sequencing. Next, we screened mutations in the atr and atm genes with the HRM assay. Nonsense mutations were identified in each gene, and the phenotypes of these nonsense mutants confirmed their loss-of-function nature. CONCLUSIONS These results demonstrate that the HRM assay is useful for screening mutations in TILLING. Furthermore, the phenotype of the obtained mutants indicates that medaka is an excellent animal model for investigating genome stability and gene function, especially when combined with TILLING.
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Affiliation(s)
- Tomoko Ishikawa
- Department of Radiation Biology and Medical Genetics, Graduate School of Medicine, Osaka University, B4, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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26
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Ataxia telangiectasia mutated nuclear localization in head and neck cancer cells is PPP2R2B-dependent. ASIAN BIOMED 2010. [DOI: 10.2478/abm-2010-0046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Background: Protein phosphatase 2A (PP2A) has been implicated in radiation-induced activation of cellular responses, likely by its ability to regulate the autophosphorylation of the ataxia telangiectasia mutated (ATM) protein, a key molecule involved in the DNA damage response initiated by double-stranded DNA breaks. Interestingly, a hereditary defect in the PPP2R2B gene, which encodes the beta isoform of PP2A regulatory subunit B, causes autosomal dominant spinocerebellar ataxia 12, a clinical condition resembling that of ataxia telangiectasia patients. Moreover, PPP2R2B is significantly down-regulated in many human cancers, including head and neck squamous cell carcinomas (HNSCCs). Objective: Examine whether PPP2R2B regulates ATM function, thereby contributing to tumor progression due to the resulting defective DNA repair. Methods: The roles of PPP2R2B were evaluated in irradiated HNSCC cell lines, siRNAPPP2R2B cells and okadaic acid treated cells. Expression of PPP2R2B was measured by microarray, Western blot analysis and real time quantitative rtPCR. ATM quantity and localization, ATM phosphorylation and γ-H2AX were determined by Western blot analysis and/or immunofluorescence assay. Clonogenic cell survival assay was performed to determine ionizing radiation sensitivity. Results: PPP2R2B expression is reduced in multiple tumor types, including HNSCCs. Indeed, HNSCC cell lines that have lower PPP2R2B mRNA expression and siRNAPPP2R2B cells lower basal and radiation-induced levels of phosphorylated ATM and the consequent reduction in the levels of phosphorylation of the downstream ATM target, γ-H2AX. Depletion of PPP2R2B and inhibition of PP2A with okadaic acid resulted in limited ATM nuclear localization. Finally, siRNAPPP2R2B cells displayed enhanced sensitivity to death after radiation. Conclusion: In HNSCCs, ATM nuclear localization is PPP2R2B dependent, and decreased PPP2R2B expression may result in limited ATM activation by preventing its nuclear accumulation and ATM-chromatin interaction. Therefore, decreased PPP2R2B expression in HNSCCs may contribute to genomic instability, cancer development and radiation sensitivity by limiting ATM functions.
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So S, Davis AJ, Chen DJ. Autophosphorylation at serine 1981 stabilizes ATM at DNA damage sites. J Cell Biol 2009; 187:977-90. [PMID: 20026654 PMCID: PMC2806275 DOI: 10.1083/jcb.200906064] [Citation(s) in RCA: 153] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Accepted: 11/20/2009] [Indexed: 11/22/2022] Open
Abstract
Ataxia telangiectasia mutated (ATM) plays a critical role in the cellular response to DNA damage. In response to DNA double-strand breaks (DSBs), ATM is autophosphorylated at serine 1981. Although this autophosphorylation is widely considered a sign of ATM activation, it is still not clear if autophosphorylation is required for ATM functions including localization to DSBs and activation of ATM kinase activity. In this study, we show that localization of ATM to DSBs is differentially regulated with the initial localization requiring the MRE11-RAD50-NBS1 complex and sustained retention requiring autophosphorylation of ATM at serine 1981. Autophosphorylated ATM interacts with MDC1 and the latter is required for the prolonged association of ATM to DSBs. Ablation of ATM autophosphorylation or knock-down of MDC1 protein affects the ability of ATM to phosphorylate downstream substrates and confer radioresistance. Together, these data suggest that autophosphorylation at serine 1981 stabilizes ATM at the sites of DSBs, and this is required for a proper DNA damage response.
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Affiliation(s)
- Sairei So
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, 75390, USA
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28
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Bolderson E, Tomimatsu N, Richard DJ, Boucher D, Kumar R, Pandita TK, Burma S, Khanna KK. Phosphorylation of Exo1 modulates homologous recombination repair of DNA double-strand breaks. Nucleic Acids Res 2009; 38:1821-31. [PMID: 20019063 PMCID: PMC2847229 DOI: 10.1093/nar/gkp1164] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
DNA double-strand break (DSB) repair via the homologous recombination pathway is a multi-stage process, which results in repair of the DSB without loss of genetic information or fidelity. One essential step in this process is the generation of extended single-stranded DNA (ssDNA) regions at the break site. This ssDNA serves to induce cell cycle checkpoints and is required for Rad51 mediated strand invasion of the sister chromatid. Here, we show that human Exonuclease 1 (Exo1) is required for the normal repair of DSBs by HR. Cells depleted of Exo1 show chromosomal instability and hypersensitivity to ionising radiation (IR) exposure. We find that Exo1 accumulates rapidly at DSBs and is required for the recruitment of RPA and Rad51 to sites of DSBs, suggesting a role for Exo1 in ssDNA generation. Interestingly, the phosphorylation of Exo1 by ATM appears to regulate the activity of Exo1 following resection, allowing optimal Rad51 loading and the completion of HR repair. These data establish a role for Exo1 in resection of DSBs in human cells, highlighting the critical requirement of Exo1 for DSB repair via HR and thus the maintenance of genomic stability.
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Affiliation(s)
- Emma Bolderson
- Signal Transduction Laboratory, Queensland Institute of Medical Research, Brisbane, Queensland 4029, Australia
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Bolderson E, Richard DJ, Edelmann W, Khanna KK. Involvement of Exo1b in DNA damage-induced apoptosis. Nucleic Acids Res 2009; 37:3452-63. [PMID: 19339515 PMCID: PMC2691832 DOI: 10.1093/nar/gkp194] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Apoptosis is essential for the maintenance of inherited genomic integrity. During DNA damage-induced apoptosis, mechanisms of cell survival, such as DNA repair are inactivated to allow cell death to proceed. Here, we describe a role for the mammalian DNA repair enzyme Exonuclease 1 (Exo1) in DNA damage-induced apoptosis. Depletion of Exo1 in human fibroblasts, or mouse embryonic fibroblasts led to a delay in DNA damage-induced apoptosis. Furthermore, we show that Exo1 acts upstream of caspase-3, DNA fragmentation and cytochrome c release. In addition, induction of apoptosis with DNA-damaging agents led to cleavage of both isoforms of Exo1. The cleavage of Exo1 was mapped to Asp514, and shown to be mediated by caspase-3. Expression of a caspase-3 cleavage site mutant form of Exo1, Asp514Ala, prevented formation of the previously observed fragment without any affect on the onset of apoptosis. We conclude that Exo1 has a role in the timely induction of apoptosis and that it is subsequently cleaved and degraded during apoptosis, potentially inhibiting DNA damage repair.
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Affiliation(s)
- Emma Bolderson
- Signal Transduction Laboratory, Queensland Institute of Medical Research, Brisbane, Queensland 4006, Australia
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30
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A novel Tel1/ATM N-terminal motif, TAN, is essential for telomere length maintenance and a DNA damage response. Mol Cell Biol 2008; 28:5736-46. [PMID: 18625723 DOI: 10.1128/mcb.00326-08] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tel1/ATM, a conserved phosphatidylinositol 3-kinase-related kinase (PIKK), acts in the response to DNA damage and regulates telomere maintenance. PIKK family members share an extended N-terminal region of low sequence homology. Sequence alignment of the N terminus of Tel1/ATM orthologs revealed a conserved, novel motif we term TAN (for Tel1/ATM N-terminal motif). Point mutations in conserved residues of the TAN motif resulted in telomere shortening, and its deletion caused the same short telomere phenotype as complete deletion of Tel1 did. Overexpressing Tel1 TAN mutants did not rescue telomere shortening. The TAN motif was also essential for the function of Tel1 in the response to DNA damage, as TAN-deleted Tel1 was indistinguishable from the complete lack of Tel1 in causing reduced viability and signaling through Rad53 upon DNA damage. Strikingly, TAN deletion reduced recruitment of Tel1 to a double-strand DNA break. Together, these results define a conserved sequence motif within an otherwise poorly defined region of the Tel1/ATM kinase family proteins that is essential for normal Tel1 function in Saccharomyces cerevisiae.
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31
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Dombernowsky SL, Weischer M, Allin KH, Bojesen SE, Tybjaerg-Hansen A, Nordestgaard BG. Risk of cancer by ATM missense mutations in the general population. J Clin Oncol 2008; 26:3057-62. [PMID: 18565893 DOI: 10.1200/jco.2007.14.6613] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
PURPOSE Truncating and missense mutations in the ATM gene, which cause insufficient DNA damage surveillance, allow damaged cells to proceed into mitosis, which eventually results in increased cancer susceptibility. We tested the hypotheses that ATM Ser49Cys and ATM Ser707Pro heterozygosity increase the risk of cancer overall, of breast cancer, and of 26 other cancer subtypes in the general population. PATIENTS AND METHODS We genotyped 10,324 individuals from the Danish general population who were observed prospectively for 36 years, during which 2,056 developed cancer. RESULTS Multifactorially adjusted hazard ratios for ATM Ser49Cys heterozygotes versus noncarriers were 1.2 (95% CI, 0.9 to 1.5) for cancer overall, 0.8 (95% CI, 0.3 to 2.0) for breast cancer, 4.8 (95% CI, 2.2 to 11) for melanoma, 2.3 (95% CI, 1.1 to 5.0) for prostate cancer, and 3.4 (95% CI, 1.1 to 11) for cancer of the oral cavity/pharynx. Multifactorially adjusted hazard ratios for ATM Ser707Pro heterozygotes versus noncarriers were 0.8 (95% CI, 0.6 to 1.2) for cancer overall, 0.6 (95% CI, 0.2 to 1.6) for breast cancer, 10 (95% CI, 1.1 to 93) for thyroid/other endocrine tumors, and 2.7 (95% CI, 1.0 to 7.6) for cancer of corpus uteri. CONCLUSION ATM missense mutations do not increase the risk of cancer overall or of breast cancer in the general population; however, we observed in exploratory analyses that ATM missense mutations may be associated with an increased risk of other cancer subtypes. As we did multiple comparisons, some of these findings could represent chance findings rather than real phenomena.
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Affiliation(s)
- Sarah Louise Dombernowsky
- Department of Clinical Biochemistry, Herlev University Hospital, Herlev Ringvej 75, DK-2730 Herlev, Denmark
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32
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Lee JH, Paull TT. Activation and regulation of ATM kinase activity in response to DNA double-strand breaks. Oncogene 2007; 26:7741-8. [PMID: 18066086 DOI: 10.1038/sj.onc.1210872] [Citation(s) in RCA: 412] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The ataxia-telangiectasia-mutated (ATM) protein kinase is rapidly and specifically activated in response to DNA double-strand breaks in eukaryotic cells. In this review, we summarize recent insights into the mechanism of ATM activation, focusing on the role of the Mre11/Rad50/Nbs1 (MRN) complex in this process. We also compare observations of the ATM activation process in different biological systems and highlight potential candidates for cellular factors that may participate in regulating ATM activity in human cells.
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Affiliation(s)
- J-H Lee
- Department of Molecular Genetics and Microbiology, Institute of Cellular and Molecular Biology, University of Texas at Austin, Austin, TX 78712, USA
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33
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Lai CK, Jeng KS, Machida K, Cheng YS, Lai MMC. Hepatitis C virus NS3/4A protein interacts with ATM, impairs DNA repair and enhances sensitivity to ionizing radiation. Virology 2007; 370:295-309. [PMID: 17931678 DOI: 10.1016/j.virol.2007.08.037] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2007] [Revised: 07/05/2007] [Accepted: 08/25/2007] [Indexed: 02/08/2023]
Abstract
Hepatitis C virus (HCV) infection is frequently associated with the development of hepatocellular carcinomas and non-Hodgkin's B-cell lymphomas. Nonstructural protein 3 (NS3) of HCV possesses serine protease, nucleoside triphosphatase, and helicase activities, while NS4A functions as a cofactor for the NS3 serine protease. Here, we show that HCV NS3/4A interacts with the ATM (ataxia-telangiectasia mutated), a cellular protein essential for cellular response to irradiation. The expression of NS3/4A caused cytoplasmic translocation of either endogenous or exogenous ATM and delayed dephosphorylation of the phosphorylated ATM and gamma-H2AX following ionizing irradiation. As a result, the irradiation-induced gamma-H2AX foci persisted longer in the NS3/4A-expressing cells. Furthermore, these cells showed increased comet tail moment in single-cell electrophoresis assay, indicating increased double-strand DNA breaks. The cells harboring an HCV replicon also exhibited cytoplasmic localization of ATM and increased sensitivity to irradiation. These results demonstrate that NS3/4A impairs the efficiency of DNA repair by interacting with ATM and renders the cells more sensitive to DNA damage. This effect may contribute to HCV oncogenesis.
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Affiliation(s)
- Chao-Kuen Lai
- Institute of Molecular Biology, Academia Sinica, Taipei, 115, Taiwan
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Berkovich E, Monnat RJ, Kastan MB. Roles of ATM and NBS1 in chromatin structure modulation and DNA double-strand break repair. Nat Cell Biol 2007; 9:683-90. [PMID: 17486112 DOI: 10.1038/ncb1599] [Citation(s) in RCA: 360] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Accepted: 04/24/2007] [Indexed: 12/20/2022]
Abstract
We developed a novel system to create DNA double-strand breaks (DSBs) at defined endogenous sites in the human genome, and used this system to detect protein recruitment and loss at and around these breaks by chromatin immunoprecipitation (ChIP). The detection of human ATM protein at site-specific DSBs required functional NBS1 protein, ATM kinase activity and ATM autophosphorylation on Ser 1981. DSB formation led to the localized disruption of nucleosomes, a process that depended on both functional NBS1 and ATM. These two proteins were also required for efficient recruitment of the repair cofactor XRCC4 to DSBs, and for efficient DSB repair. These results demonstrate the functional importance of ATM kinase activity and phosphorylation in the response to DSBs, and support a model in which ordered chromatin structure changes that occur after DNA breakage depend on functional NBS1 and ATM, and facilitate DNA DSB repair.
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Affiliation(s)
- Elijahu Berkovich
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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35
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Haince JF, Kozlov S, Dawson VL, Dawson TM, Hendzel MJ, Lavin MF, Poirier GG. Ataxia telangiectasia mutated (ATM) signaling network is modulated by a novel poly(ADP-ribose)-dependent pathway in the early response to DNA-damaging agents. J Biol Chem 2007; 282:16441-53. [PMID: 17428792 DOI: 10.1074/jbc.m608406200] [Citation(s) in RCA: 199] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Poly(ADP-ribosyl)ation is a post-translational modification that is instantly stimulated by DNA strand breaks creating a unique signal for the modulation of protein functions in DNA repair and cell cycle checkpoint pathways. Here we report that lack of poly(ADP-ribose) synthesis leads to a compromised response to DNA damage. Deficiency in poly(ADP-ribosyl)ation metabolism induces profound cellular sensitivity to DNA-damaging agents, particularly in cells deficient for the protein kinase ataxia telangiectasia mutated (ATM). At the biochemical level, we examined the significance of poly(ADP-ribose) synthesis on the regulation of early DNA damage-induced signaling cascade initiated by ATM. Using potent PARP inhibitors and PARP-1 knock-out cells, we demonstrate a functional interplay between ATM and poly(ADP-ribose) that is important for the phosphorylation of p53, SMC1, and H2AX. For the first time, we demonstrate a functional and physical interaction between the major DSB signaling kinase, ATM and poly(ADP-ribosyl)ation by PARP-1, a key enzyme of chromatin remodeling. This study suggests that poly(ADP-ribose) might serve as a DNA damage sensory molecule that is critical for early DNA damage signaling.
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Affiliation(s)
- Jean-François Haince
- Health and Environment Unit, Laval University Hospital Research Center, CHUQ, Faculty of Medicine, Laval University, Quebec, Quebec G1V 4G2, Canada
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36
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Stredrick DL, Garcia-Closas M, Pineda MA, Bhatti P, Alexander BH, Doody MM, Lissowska J, Peplonska B, Brinton LA, Chanock SJ, Struewing JP, Sigurdson AJ. The ATM missense mutation p.Ser49Cys (c.146C>G) and the risk of breast cancer. Hum Mutat 2006; 27:538-44. [PMID: 16652348 PMCID: PMC1850333 DOI: 10.1002/humu.20323] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Homozygous mutation in the ATM gene causes ataxia telangiectasia and heterozygous mutation carriers may be at increased risk of breast cancer. We studied a total of 22 ATM variants; 18 variants were analyzed in one of two large population-based studies from the U.S. and Poland, and four variants were analyzed in all 2,856 breast cancer cases and 3,344 controls from the two studies. The missense mutation Ser49Cys (c.146C>G, p.S49C), carried by approximately 2% of subjects, was more common in cases than controls in both study populations, combined odds ratio (OR) 1.69 (95% CI, 1.19-2.40; P=0.004). Another missense mutation at approximately 2% frequency, Phe858Leu (c.2572T>C, p.F858L), was associated with a significant increased risk in the U.S. study but not in Poland, and had a combined OR of 1.44 (95% CI, 0.98-2.11; P=0.06). These analyses provide the most convincing evidence thus far that missense mutations in ATM, particularly p.S49C, may be breast cancer susceptibility alleles. Because of their low frequency, even larger sample sizes are required to more firmly establish these associations.
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Affiliation(s)
- Denise L. Stredrick
- Laboratory of Population Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Montserrat Garcia-Closas
- Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Marbin A. Pineda
- Laboratory of Population Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Parveen Bhatti
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Bruce H. Alexander
- Division of Environmental and Occupational Health, University of Minnesota, Minneapolis, MN, USA
| | - Michele M. Doody
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jolanta Lissowska
- Division of Cancer Epidemiology and Prevention, Cancer Center and M. Sklodowska-Curie Institute of Oncology, Warsaw, Poland
| | - Beata Peplonska
- Department of Occupational and Environmental Epidemiology, Nofer Institute of Occupational Medicine, Łódź, Poland
| | - Louise A. Brinton
- Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Stephen J. Chanock
- Core Genotyping Facility, National Cancer Institute, National Institutes of Health, Gaithersburg, MD, USA
| | - Jeffery P. Struewing
- Laboratory of Population Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Correspondence to: Jeffery P Struewing, Laboratory of Population Genetics, National Cancer Institute, 41 Library Dr, Room D702, Bethesda, MD 20892-5060, USA;
| | - Alice J. Sigurdson
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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Kutty RK, Chen S, Samuel W, Vijayasarathy C, Duncan T, Tsai JY, Fariss RN, Carper D, Jaworski C, Wiggert B. Cell density-dependent nuclear/cytoplasmic localization of NORPEG (RAI14) protein. Biochem Biophys Res Commun 2006; 345:1333-41. [PMID: 16729964 DOI: 10.1016/j.bbrc.2006.04.184] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2006] [Accepted: 04/29/2006] [Indexed: 11/21/2022]
Abstract
NORPEG (RAI14), a developmentally regulated gene induced by retinoic acid, encodes a 980 amino acid (aa) residue protein containing six ankyrin repeats and a long coiled-coil domain [Kutty et al., J. Biol. Chem. 276 (2001), pp. 2831-2840]. We have expressed aa residues 1-287 of NORPEG and used the recombinant protein to produce an anti-NORPEG polyclonal antibody. Confocal immunofluorescence analysis showed that the subcellular localization of NORPEG in retinal pigment epithelial (ARPE-19) cells varies with cell density, with predominantly nuclear localization in nonconfluent cells, but a cytoplasmic localization, reminiscent of cytoskeleton, in confluent cultures. Interestingly, an evolutionarily conserved putative monopartite nuclear localization signal (P(270)KKRKAP(276)) was identified by analyzing the sequences of NORPEG and its orthologs. GFP-NORPEG (2-287 aa), a fusion protein containing this signal, was indeed localized to nuclei when expressed in ARPE-19 or COS-7 cells. Deletion and mutation analysis indicated that the identified nuclear localization sequence is indispensable for nuclear targeting.
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Affiliation(s)
- R Krishnan Kutty
- Section on Biochemistry, Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Biton S, Dar I, Mittelman L, Pereg Y, Barzilai A, Shiloh Y. Nuclear ataxia-telangiectasia mutated (ATM) mediates the cellular response to DNA double strand breaks in human neuron-like cells. J Biol Chem 2006; 281:17482-17491. [PMID: 16627474 DOI: 10.1074/jbc.m601895200] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The protein kinase ATM (ataxia-telangiectasia mutated) activates the cellular response to double strand breaks (DSBs), a highly cytotoxic DNA lesion. ATM is activated by DSBs and in turn phosphorylates key players in numerous damage response pathways. ATM is missing or inactivated in the autosomal recessive disorder ataxia-telangiectasia (A-T), which is characterized by neuronal degeneration, immunodeficiency, genomic instability, radiation sensitivity, and cancer predisposition. The predominant symptom of A-T is a progressive loss of movement coordination due to ongoing degeneration of the cerebellar cortex and peripheral neuropathy. A major deficiency in understanding A-T is the lack of information on the role of ATM in neurons. It is unclear whether the ATM-mediated DSB response operates in these cells similarly to proliferating cells. Furthermore, ATM was reported to be cytoplasmic in neurons and suggested to function in these cells in capacities other than the DNA damage response. Recently we obtained genetic molecular evidence that the neuronal degeneration in A-T does result from defective DNA damage response. We therefore undertook to investigate this response in a model system of human neuron-like cells (NLCs) obtained by neuronal differentiation in culture. ATM was largely nuclear in NLCs, and their ATM-mediated responses to DSBs were similar to those of proliferating cells. Knocking down ATM did not interfere with neuronal differentiation but abolished ATM-mediated damage responses in NLCs. We concluded that nuclear ATM mediates the DSB response in NLCs similarly to in proliferating cells. Attempts to understand the neurodegeneration in A-T should be directed to investigating the DSB response in the nervous system.
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Affiliation(s)
- Sharon Biton
- The David and Inez Myers Laboratory for Genetic Research, Department of Molecular Genetics and Biochemistry, Tel Aviv University, Tel Aviv 69978, Israel
| | - Inbal Dar
- Department of Neurobiochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Leonid Mittelman
- Interdepartmental Core Facility, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yaron Pereg
- The David and Inez Myers Laboratory for Genetic Research, Department of Molecular Genetics and Biochemistry, Tel Aviv University, Tel Aviv 69978, Israel
| | - Ari Barzilai
- Department of Neurobiochemistry, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel
| | - Yosef Shiloh
- The David and Inez Myers Laboratory for Genetic Research, Department of Molecular Genetics and Biochemistry, Tel Aviv University, Tel Aviv 69978, Israel.
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