1
|
Martins DJ, Di Lazzaro Filho R, Bertola DR, Hoch NC. Rothmund-Thomson syndrome, a disorder far from solved. FRONTIERS IN AGING 2023; 4:1296409. [PMID: 38021400 PMCID: PMC10676203 DOI: 10.3389/fragi.2023.1296409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 10/17/2023] [Indexed: 12/01/2023]
Abstract
Rothmund-Thomson syndrome (RTS) is a rare autosomal recessive disorder characterized by a range of clinical symptoms, including poikiloderma, juvenile cataracts, short stature, sparse hair, eyebrows/eyelashes, nail dysplasia, and skeletal abnormalities. While classically associated with mutations in the RECQL4 gene, which encodes a DNA helicase involved in DNA replication and repair, three additional genes have been recently identified in RTS: ANAPC1, encoding a subunit of the APC/C complex; DNA2, which encodes a nuclease/helicase involved in DNA repair; and CRIPT, encoding a poorly characterized protein implicated in excitatory synapse formation and splicing. Here, we review the clinical spectrum of RTS patients, analyze the genetic basis of the disease, and discuss molecular functions of the affected genes, drawing some novel genotype-phenotype correlations and proposing avenues for future studies into this enigmatic disorder.
Collapse
Affiliation(s)
- Davi Jardim Martins
- Genomic Stability Unit, Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Ricardo Di Lazzaro Filho
- Center for Human Genome Studies, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
- Dasa Genômica/Genera, Genômica, São Paulo, Brazil
| | - Debora Romeo Bertola
- Center for Human Genome Studies, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
- Genetics Unit, Department of Pediatrics, Faculty of Medicine, Children’s Institute, Hospital das Clínicas, University of São Paulo, São Paulo, Brazil
| | - Nícolas Carlos Hoch
- Genomic Stability Unit, Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| |
Collapse
|
2
|
Dueva R, Krieger LM, Li F, Luo D, Xiao H, Stuschke M, Metzen E, Iliakis G. Chemical Inhibition of RPA by HAMNO Alters Cell Cycle Dynamics by Impeding DNA Replication and G2-to-M Transition but Has Little Effect on the Radiation-Induced DNA Damage Response. Int J Mol Sci 2023; 24:14941. [PMID: 37834389 PMCID: PMC10573259 DOI: 10.3390/ijms241914941] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/28/2023] [Accepted: 10/01/2023] [Indexed: 10/15/2023] Open
Abstract
Replication protein A (RPA) is the major single-stranded DNA (ssDNA) binding protein that is essential for DNA replication and processing of DNA double-strand breaks (DSBs) by homology-directed repair pathways. Recently, small molecule inhibitors have been developed targeting the RPA70 subunit and preventing RPA interactions with ssDNA and various DNA repair proteins. The rationale of this development is the potential utility of such compounds as cancer therapeutics, owing to their ability to inhibit DNA replication that sustains tumor growth. Among these compounds, (1Z)-1-[(2-hydroxyanilino) methylidene] naphthalen-2-one (HAMNO) has been more extensively studied and its efficacy against tumor growth was shown to arise from the associated DNA replication stress. Here, we study the effects of HAMNO on cells exposed to ionizing radiation (IR), focusing on the effects on the DNA damage response and the processing of DSBs and explore its potential as a radiosensitizer. We show that HAMNO by itself slows down the progression of cells through the cell cycle by dramatically decreasing DNA synthesis. Notably, HAMNO also attenuates the progression of G2-phase cells into mitosis by a mechanism that remains to be elucidated. Furthermore, HAMNO increases the fraction of chromatin-bound RPA in S-phase but not in G2-phase cells and suppresses DSB repair by homologous recombination. Despite these marked effects on the cell cycle and the DNA damage response, radiosensitization could neither be detected in exponentially growing cultures, nor in cultures enriched in G2-phase cells. Our results complement existing data on RPA inhibitors, specifically HAMNO, and suggest that their antitumor activity by replication stress induction may not extend to radiosensitization. However, it may render cells more vulnerable to other forms of DNA damaging agents through synthetically lethal interactions, which requires further investigation.
Collapse
Affiliation(s)
- Rositsa Dueva
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Lisa Marie Krieger
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- Division of Experimental Radiation Biology, Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Fanghua Li
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- West German Proton Therapy Centre Essen (WPE), 45147 Essen, Germany
| | - Daxian Luo
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- Division of Experimental Radiation Biology, Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Huaping Xiao
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- Division of Experimental Radiation Biology, Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Martin Stuschke
- Division of Experimental Radiation Biology, Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, 45147 Essen, Germany
- German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Eric Metzen
- Institute of Physiology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - George Iliakis
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (L.M.K.); (F.L.); (D.L.); (H.X.)
- Division of Experimental Radiation Biology, Department of Radiotherapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| |
Collapse
|
3
|
Li F, Mladenov E, Sun Y, Soni A, Stuschke M, Timmermann B, Iliakis G. Low CDK Activity and Enhanced Degradation by APC/C CDH1 Abolishes CtIP Activity and Alt-EJ in Quiescent Cells. Cells 2023; 12:1530. [PMID: 37296650 PMCID: PMC10252496 DOI: 10.3390/cells12111530] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 05/26/2023] [Accepted: 05/27/2023] [Indexed: 06/12/2023] Open
Abstract
Alt-EJ is an error-prone DNA double-strand break (DSBs) repair pathway coming to the fore when first-line repair pathways, c-NHEJ and HR, are defective or fail. It is thought to benefit from DNA end-resection-a process whereby 3' single-stranded DNA-tails are generated-initiated by the CtIP/MRE11-RAD50-NBS1 (MRN) complex and extended by EXO1 or the BLM/DNA2 complex. The connection between alt-EJ and resection remains incompletely characterized. Alt-EJ depends on the cell cycle phase, is at maximum in G2-phase, substantially reduced in G1-phase and almost undetectable in quiescent, G0-phase cells. The mechanism underpinning this regulation remains uncharacterized. Here, we compare alt-EJ in G1- and G0-phase cells exposed to ionizing radiation (IR) and identify CtIP-dependent resection as the key regulator. Low levels of CtIP in G1-phase cells allow modest resection and alt-EJ, as compared to G2-phase cells. Strikingly, CtIP is undetectable in G0-phase cells owing to APC/C-mediated degradation. The suppression of CtIP degradation with bortezomib or CDH1-depletion rescues CtIP and alt-EJ in G0-phase cells. CtIP activation in G0-phase cells also requires CDK-dependent phosphorylation by any available CDK but is restricted to CDK4/6 at the early stages of the normal cell cycle. We suggest that suppression of mutagenic alt-EJ in G0-phase is a mechanism by which cells of higher eukaryotes maintain genomic stability in a large fraction of non-cycling cells in their organisms.
Collapse
Affiliation(s)
- Fanghua Li
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
| | - Emil Mladenov
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Yanjie Sun
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
| | - Aashish Soni
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| | - Martin Stuschke
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, German Cancer Research Center (DKFZ), 45147 Essen, Germany
| | - Beate Timmermann
- Department of Particle Therapy, University Hospital Essen, West German Proton Therapy Centre Essen (WPE), West German Cancer Center (WTZ), German Cancer Consortium (DKTK), 45147 Essen, Germany;
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, German Cancer Research Center (DKFZ), 45147 Essen, Germany
| | - George Iliakis
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany; (F.L.); (E.M.); (Y.S.); (A.S.)
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45147 Essen, Germany;
| |
Collapse
|
4
|
Ceppi I, Cannavo E, Bret H, Camarillo R, Vivalda F, Thakur RS, Romero-Franco A, Sartori AA, Huertas P, Guérois R, Cejka P. PLK1 regulates CtIP and DNA2 interplay in long-range DNA end resection. Genes Dev 2023; 37:119-135. [PMID: 36746606 PMCID: PMC10069449 DOI: 10.1101/gad.349981.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 01/12/2023] [Indexed: 02/08/2023]
Abstract
DNA double-strand break (DSB) repair is initiated by DNA end resection. CtIP acts in short-range resection to stimulate MRE11-RAD50-NBS1 (MRN) to endonucleolytically cleave 5'-terminated DNA to bypass protein blocks. CtIP also promotes the DNA2 helicase-nuclease to accelerate long-range resection downstream from MRN. Here, using AlphaFold2, we identified CtIP-F728E-Y736E as a separation-of-function mutant that is still proficient in conjunction with MRN but is not able to stimulate ssDNA degradation by DNA2. Accordingly, CtIP-F728E-Y736E impairs physical interaction with DNA2. Cellular assays revealed that CtIP-F728E-Y736E cells exhibit reduced DSB-dependent chromatin-bound RPA, impaired long-range resection, and increased sensitivity to DSB-inducing drugs. Previously, CtIP was shown to be targeted by PLK1 to inhibit long-range resection, yet the underlying mechanism was unclear. We show that the DNA2-interacting region in CtIP includes the PLK1 target site at S723. The integrity of S723 in CtIP is necessary for the stimulation of DNA2, and phosphorylation of CtIP by PLK1 in vitro is consequently inhibitory, explaining why PLK1 restricts long-range resection. Our data support a model in which CDK-dependent phosphorylation of CtIP activates resection by MRN in S phase, and PLK1-mediated phosphorylation of CtIP disrupts CtIP stimulation of DNA2 to attenuate long-range resection later at G2/M.
Collapse
Affiliation(s)
- Ilaria Ceppi
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), Bellinzona 6500, Switzerland
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich 8093, Switzerland
| | - Elda Cannavo
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), Bellinzona 6500, Switzerland
| | - Hélène Bret
- Institute for Integrative Biology of the Cell (I2BC), Commissariat à l'Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette 91190, France
| | - Rosa Camarillo
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Sevilla 41080, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, Sevilla 41092, Spain
| | - Francesca Vivalda
- Institute of Molecular Cancer Research, University of Zürich, Zürich 8057, Switzerland
| | - Roshan Singh Thakur
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), Bellinzona 6500, Switzerland
| | - Amador Romero-Franco
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Sevilla 41080, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, Sevilla 41092, Spain
| | - Alessandro A Sartori
- Institute of Molecular Cancer Research, University of Zürich, Zürich 8057, Switzerland
| | - Pablo Huertas
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Sevilla 41080, Spain
- Centro Andaluz de Biología Molecular y Medicina Regenerativa (CABIMER), Universidad de Sevilla-Consejo Superior de Investigaciones Científicas-Universidad Pablo de Olavide, Sevilla 41092, Spain
| | - Raphaël Guérois
- Institute for Integrative Biology of the Cell (I2BC), Commissariat à l'Energie Atomique, Centre National de la Recherche Scientifique, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette 91190, France
| | - Petr Cejka
- Institute for Research in Biomedicine, Faculty of Biomedical Sciences, Università della Svizzera italiana (USI), Bellinzona 6500, Switzerland;
- Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich 8093, Switzerland
| |
Collapse
|
5
|
Shift in G1-Checkpoint from ATM-Alone to a Cooperative ATM Plus ATR Regulation with Increasing Dose of Radiation. Cells 2021; 11:cells11010063. [PMID: 35011623 PMCID: PMC8750242 DOI: 10.3390/cells11010063] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/23/2021] [Accepted: 12/24/2021] [Indexed: 12/13/2022] Open
Abstract
The current view of the involvement of PI3-kinases in checkpoint responses after DNA damage is that ATM is the key regulator of G1-, S- or G2-phase checkpoints, that ATR is only partly involved in the regulation of S- and G2-phase checkpoints and that DNA-PKcs is not involved in checkpoint regulation. However, further analysis of the contributions of these kinases to checkpoint responses in cells exposed to ionizing radiation (IR) recently uncovered striking integrations and interplays among ATM, ATR and DNA-PKcs that adapt not only to the phase of the cell cycle in which cells are irradiated, but also to the load of DNA double-strand breaks (DSBs), presumably to optimize their processing. Specifically, we found that low IR doses in G2-phase cells activate a G2-checkpoint that is regulated by epistatically coupled ATM and ATR. Thus, inhibition of either kinase suppresses almost fully its activation. At high IR doses, the epistatic ATM/ATR coupling relaxes, yielding to a cooperative regulation. Thus, single-kinase inhibition suppresses partly, and only combined inhibition suppresses fully G2-checkpoint activation. Interestingly, DNA-PKcs integrates with ATM/ATR in G2-checkpoint control, but functions in its recovery in a dose-independent manner. Strikingly, irradiation during S-phase activates, independently of dose, an exclusively ATR-dependent G2 checkpoint. Here, ATM couples with DNA-PKcs to regulate checkpoint recovery. In the present work, we extend these studies and investigate organization and functions of these PI3-kinases in the activation of the G1 checkpoint in cells irradiated either in the G0 or G1 phase. We report that ATM is the sole regulator of the G1 checkpoint after exposure to low IR doses. At high IR doses, ATM remains dominant, but contributions from ATR also become detectable and are associated with limited ATM/ATR-dependent end resection at DSBs. Under these conditions, only combined ATM + ATR inhibition fully abrogates checkpoint and resection. Contributions of DNA-PKcs and CHK2 to the regulation of the G1 checkpoint are not obvious in these experiments and may be masked by the endpoint employed for checkpoint analysis and perturbations in normal progression through the cell cycle of cells exposed to DNA-PKcs inhibitors. The results broaden our understanding of organization throughout the cell cycle and adaptation with increasing IR dose of the ATM/ATR/DNA-PKcs module to regulate checkpoint responses. They emphasize notable similarities and distinct differences between G1-, G2- and S-phase checkpoint regulation that may guide DSB processing decisions.
Collapse
|