1
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Mackay HL, Stone HR, Ronson GE, Ellis K, Lanz A, Aghabi Y, Walker AK, Starowicz K, Garvin AJ, Van Eijk P, Koestler SA, Anthony EJ, Piberger AL, Chauhan AS, Conway-Thomas P, Vaitsiankova A, Vijayendran S, Beesley JF, Petermann E, Brown EJ, Densham RM, Reed SH, Dobbs F, Saponaro M, Morris JR. USP50 suppresses alternative RecQ helicase use and deleterious DNA2 activity during replication. Nat Commun 2024; 15:8102. [PMID: 39284827 PMCID: PMC11405836 DOI: 10.1038/s41467-024-52250-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 08/30/2024] [Indexed: 09/22/2024] Open
Abstract
Mammalian DNA replication relies on various DNA helicase and nuclease activities to ensure accurate genetic duplication, but how different helicase and nuclease activities are properly directed remains unclear. Here, we identify the ubiquitin-specific protease, USP50, as a chromatin-associated protein required to promote ongoing replication, fork restart, telomere maintenance, cellular survival following hydroxyurea or pyridostatin treatment, and suppression of DNA breaks near GC-rich sequences. We find that USP50 supports proper WRN-FEN1 localisation at or near stalled replication forks. Nascent DNA in cells lacking USP50 shows increased association of the DNA2 nuclease and RECQL4 and RECQL5 helicases and replication defects in cells lacking USP50, or FEN1 are driven by these proteins. Consequently, suppression of DNA2 or RECQL4/5 improves USP50-depleted cell resistance to agents inducing replicative stress and restores telomere stability. These data define an unexpected regulatory protein that promotes the balance of helicase and nuclease use at ongoing and stalled replication forks.
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Affiliation(s)
- Hannah L Mackay
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Helen R Stone
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- CCTT-C Cancer Research UK, Clinical trials unit, Sir Robert Aitken building, College of Medicine and Health, University of Birmingham, Birmingham, B15 2TT, UK
| | - George E Ronson
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Katherine Ellis
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- School of Chemical, Materials and Biological Engineering, University of Sheffield, Mappin Street, Sheffield, S1 3JD, UK
| | - Alexander Lanz
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Yara Aghabi
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Alexandra K Walker
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Katarzyna Starowicz
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- Adthera Bio, Lyndon House, 62 Hagley Road, Birmingham, B16 8PE, UK
| | - Alexander J Garvin
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- SUMO Biology Lab, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Patrick Van Eijk
- Broken String Biosciences Ltd., BioData Innovation Centre, Unit AB3-03, Level 3, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1DR, UK
- Division of Cancer & Genetics School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK
| | - Stefan A Koestler
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Elizabeth J Anthony
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Ann Liza Piberger
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Anoop S Chauhan
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Poppy Conway-Thomas
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Alina Vaitsiankova
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9RQ, UK
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, New York, NY, USA
| | - Sobana Vijayendran
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
- University Hospital Birmingham N.H.S. Foundation Trust, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Birmingham, B15 2TH, UK
| | - James F Beesley
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Eva Petermann
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Eric J Brown
- Abramson Family Cancer Research Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, 421 Curie Boulevard PA, 19104-6160, USA
| | - Ruth M Densham
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Simon H Reed
- Broken String Biosciences Ltd., BioData Innovation Centre, Unit AB3-03, Level 3, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1DR, UK
- Division of Cancer & Genetics School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK
| | - Felix Dobbs
- Broken String Biosciences Ltd., BioData Innovation Centre, Unit AB3-03, Level 3, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1DR, UK
- Division of Cancer & Genetics School of Medicine, Cardiff University, Heath Park, Cardiff, CF14 4XN, UK
| | - Marco Saponaro
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Joanna R Morris
- Birmingham Centre for Genome Biology and Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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2
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Hwang SY, Kim H, Denisko D, Zhao B, Lee D, Jeong J, Kim J, Park K, Park J, Jeong D, Park S, Choi HJ, Kim S, Lee EA, Ahn K. Human cytomegalovirus harnesses host L1 retrotransposon for efficient replication. Nat Commun 2024; 15:7640. [PMID: 39223139 PMCID: PMC11369119 DOI: 10.1038/s41467-024-51961-y] [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: 12/17/2023] [Accepted: 08/20/2024] [Indexed: 09/04/2024] Open
Abstract
Genetic parasites, including viruses and transposons, exploit components from the host for their own replication. However, little is known about virus-transposon interactions within host cells. Here, we discover a strategy where human cytomegalovirus (HCMV) hijacks L1 retrotransposon encoded protein during its replication cycle. HCMV infection upregulates L1 expression by enhancing both the expression of L1-activating transcription factors, YY1 and RUNX3, and the chromatin accessibility of L1 promoter regions. Increased L1 expression, in turn, promotes HCMV replicative fitness. Affinity proteomics reveals UL44, HCMV DNA polymerase subunit, as the most abundant viral binding protein of the L1 ribonucleoprotein (RNP) complex. UL44 directly interacts with L1 ORF2p, inducing DNA damage responses in replicating HCMV compartments. While increased L1-induced mutagenesis is not observed in HCMV for genetic adaptation, the interplay between UL44 and ORF2p accelerates viral DNA replication by alleviating replication stress. Our findings shed light on how HCMV exploits host retrotransposons for enhanced viral fitness.
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Affiliation(s)
- Sung-Yeon Hwang
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hyewon Kim
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Danielle Denisko
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA
| | - Boxun Zhao
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02115, USA
- Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, 02115, USA
| | - Dohoon Lee
- Bioinformatics Institute, Seoul National University, Seoul, 08826, Republic of Korea
- BK21 FOUR Intelligence Computing, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jiseok Jeong
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Jinuk Kim
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Kiwon Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Junhyun Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Dongjoon Jeong
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sehong Park
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hee-Jung Choi
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sun Kim
- Department of Computer Science and Engineering, Seoul National University, Seoul, 08826, Republic of Korea
| | - Eunjung Alice Lee
- Division of Genetics and Genomics, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, 02115, USA.
- Broad Institute of MIT and Harvard, Cambridge, MA, 02115, USA.
- Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA, 02115, USA.
| | - Kwangseog Ahn
- Center for RNA Research, Institute for Basic Science, Seoul, 08826, Republic of Korea.
- School of Biological Sciences, Seoul National University, Seoul, 08826, Republic of Korea.
- SNU Institute for Virus Research, Seoul National University, Seoul, 08826, Republic of Korea.
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Krasikova YS, Maltseva EA, Khodyreva SN, Evdokimov AN, Rechkunova NI, Lavrik OI. Does the XPA-FEN1 Interaction Concern to Nucleotide Excision Repair or Beyond? Biomolecules 2024; 14:814. [PMID: 39062528 PMCID: PMC11274875 DOI: 10.3390/biom14070814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/28/2024] [Accepted: 07/04/2024] [Indexed: 07/28/2024] Open
Abstract
Nucleotide excision repair (NER) is the most universal repair pathway, which removes a wide range of DNA helix-distorting lesions caused by chemical or physical agents. The final steps of this repair process are gap-filling repair synthesis and subsequent ligation. XPA is the central NER scaffolding protein factor and can be involved in post-incision NER stages. Replication machinery is loaded after the first incision of the damaged strand that is performed by the XPF-ERCC1 nuclease forming a damaged 5'-flap processed by the XPG endonuclease. Flap endonuclease I (FEN1) is a critical component of replication machinery and is absolutely indispensable for the maturation of newly synthesized strands. FEN1 also contributes to the long-patch pathway of base excision repair. Here, we use a set of DNA substrates containing a fluorescently labeled 5'-flap and different size gap to analyze possible repair factor-replication factor interactions. Ternary XPA-FEN1-DNA complexes with each tested DNA are detected. Furthermore, we demonstrate XPA-FEN1 complex formation in the absence of DNA due to protein-protein interaction. Functional assays reveal that XPA moderately inhibits FEN1 catalytic activity. Using fluorescently labeled XPA, formation of ternary RPA-XPA-FEN1 complex, where XPA accommodates FEN1 and RPA contacts simultaneously, can be proposed. We discuss possible functional roles of the XPA-FEN1 interaction in NER related DNA resynthesis and/or other DNA metabolic processes where XPA can be involved in the complex with FEN1.
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Affiliation(s)
- Yuliya S. Krasikova
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
| | - Ekaterina A. Maltseva
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
| | - Svetlana N. Khodyreva
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
| | - Alexey N. Evdokimov
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
| | - Nadejda I. Rechkunova
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
| | - Olga I. Lavrik
- Institute of Chemical Biology and Fundamental Medicine, 630090 Novosibirsk, Russia; (Y.S.K.); (E.A.M.); (S.N.K.); (A.N.E.); (N.I.R.)
- Department of Natural Sciences, Novosibirsk State University, 630090 Novosibirsk, Russia
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Berfelde J, Hildebrand LS, Kuhlmann L, Fietkau R, Distel LV. FEN1 Inhibition as a Potential Novel Targeted Therapy against Breast Cancer and the Prognostic Relevance of FEN1. Int J Mol Sci 2024; 25:2110. [PMID: 38396787 PMCID: PMC10889347 DOI: 10.3390/ijms25042110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Revised: 02/05/2024] [Accepted: 02/07/2024] [Indexed: 02/25/2024] Open
Abstract
To improve breast cancer treatment and to enable new strategies for therapeutic resistance, therapeutic targets are constantly being studied. Potential targets are proteins of DNA repair and replication and genomic integrity, such as Flap Endonuclease 1 (FEN1). This study investigated the effects of FEN1 inhibitor FEN1-IN-4 in combination with ionizing radiation on cell death, clonogenic survival, the cell cycle, senescence, doubling time, DNA double-strand breaks and micronuclei in breast cancer cells, breast cells and healthy skin fibroblasts. Furthermore, the variation in the baseline FEN1 level and its influence on treatment prognosis was investigated. The cell lines show specific response patterns in the aspects studied and have heterogeneous baseline FEN1 levels. FEN1-IN-4 has cytotoxic, cytostatic and radiosensitizing effects, expressed through increasing cell death by apoptosis and necrosis, G2M share, senescence, double-strand breaks and a reduced survival fraction. Nevertheless, some cells are less affected by the cytotoxicity and fibroblasts show a rather limited response. In vivo, high FEN1 mRNA expression worsens the prognosis of breast cancer patients. Due to the increased expression in breast cancer tissue, FEN1 could represent a new tumor and prognosis marker and FEN1-IN-4 may serve as a new potent agent in personalized medicine and targeted breast cancer therapy.
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Affiliation(s)
- Johanna Berfelde
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Laura S. Hildebrand
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Lukas Kuhlmann
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Rainer Fietkau
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
| | - Luitpold V. Distel
- Department of Radiation Oncology, Universitätsklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
- Comprehensive Cancer Center Erlangen-Europäische Metropolregion Nürnberg (CCC ER-EMN), 91054 Erlangen, Germany
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5
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Nickoloff JA, Jaiswal AS, Sharma N, Williamson EA, Tran MT, Arris D, Yang M, Hromas R. Cellular Responses to Widespread DNA Replication Stress. Int J Mol Sci 2023; 24:16903. [PMID: 38069223 PMCID: PMC10707325 DOI: 10.3390/ijms242316903] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Replicative DNA polymerases are blocked by nearly all types of DNA damage. The resulting DNA replication stress threatens genome stability. DNA replication stress is also caused by depletion of nucleotide pools, DNA polymerase inhibitors, and DNA sequences or structures that are difficult to replicate. Replication stress triggers complex cellular responses that include cell cycle arrest, replication fork collapse to one-ended DNA double-strand breaks, induction of DNA repair, and programmed cell death after excessive damage. Replication stress caused by specific structures (e.g., G-rich sequences that form G-quadruplexes) is localized but occurs during the S phase of every cell division. This review focuses on cellular responses to widespread stress such as that caused by random DNA damage, DNA polymerase inhibition/nucleotide pool depletion, and R-loops. Another form of global replication stress is seen in cancer cells and is termed oncogenic stress, reflecting dysregulated replication origin firing and/or replication fork progression. Replication stress responses are often dysregulated in cancer cells, and this too contributes to ongoing genome instability that can drive cancer progression. Nucleases play critical roles in replication stress responses, including MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, FEN1, and TATDN2. Several of these nucleases cleave branched DNA structures at stressed replication forks to promote repair and restart of these forks. We recently defined roles for EEPD1 in restarting stressed replication forks after oxidative DNA damage, and for TATDN2 in mitigating replication stress caused by R-loop accumulation in BRCA1-defective cells. We also discuss how insights into biological responses to genome-wide replication stress can inform novel cancer treatment strategies that exploit synthetic lethal relationships among replication stress response factors.
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Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Aruna S. Jaiswal
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Elizabeth A. Williamson
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Manh T. Tran
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Dominic Arris
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Ming Yang
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Robert Hromas
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
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6
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Laverde EE, Polyzos AA, Tsegay PP, Shaver M, Hutcheson JD, Balakrishnan L, McMurray CT, Liu Y. Flap Endonuclease 1 Endonucleolytically Processes RNA to Resolve R-Loops through DNA Base Excision Repair. Genes (Basel) 2022; 14:genes14010098. [PMID: 36672839 PMCID: PMC9859040 DOI: 10.3390/genes14010098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 12/22/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022] Open
Abstract
Flap endonuclease 1 (FEN1) is an essential enzyme that removes RNA primers and base lesions during DNA lagging strand maturation and long-patch base excision repair (BER). It plays a crucial role in maintaining genome stability and integrity. FEN1 is also implicated in RNA processing and biogenesis. A recent study from our group has shown that FEN1 is involved in trinucleotide repeat deletion by processing the RNA strand in R-loops through BER, further suggesting that the enzyme can modulate genome stability by facilitating the resolution of R-loops. However, it remains unknown how FEN1 can process RNA to resolve an R-loop. In this study, we examined the FEN1 cleavage activity on the RNA:DNA hybrid intermediates generated during DNA lagging strand processing and BER in R-loops. We found that both human and yeast FEN1 efficiently cleaved an RNA flap in the intermediates using its endonuclease activity. We further demonstrated that FEN1 was recruited to R-loops in normal human fibroblasts and senataxin-deficient (AOA2) fibroblasts, and its R-loop recruitment was significantly increased by oxidative DNA damage. We showed that FEN1 specifically employed its endonucleolytic cleavage activity to remove the RNA strand in an R-loop during BER. We found that FEN1 coordinated its DNA and RNA endonucleolytic cleavage activity with the 3'-5' exonuclease of APE1 to resolve the R-loop. Our results further suggest that FEN1 employed its unique tracking mechanism to endonucleolytically cleave the RNA strand in an R-loop by coordinating with other BER enzymes and cofactors during BER. Our study provides the first evidence that FEN1 endonucleolytic cleavage can result in the resolution of R-loops via the BER pathway, thereby maintaining genome integrity.
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Affiliation(s)
- Eduardo E. Laverde
- Biochemistry Ph.D. Program, Florida International University, Miami, FL 33199, USA
| | - Aris A. Polyzos
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Pawlos P. Tsegay
- Biochemistry Ph.D. Program, Florida International University, Miami, FL 33199, USA
| | - Mohammad Shaver
- Department of Biomedical Engineering, Florida International University, Miami, FL 33199, USA
| | - Joshua D. Hutcheson
- Department of Biomedical Engineering, Florida International University, Miami, FL 33199, USA
| | - Lata Balakrishnan
- Department of Biology, Indiana-Purdue University, Indianapolis, IN 46202, USA
| | - Cynthia T. McMurray
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Yuan Liu
- Biochemistry Ph.D. Program, Florida International University, Miami, FL 33199, USA
- Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
- Correspondence:
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7
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Tang Q, Liu Y, Liu Y, Zhu F, Yu Q, Chen H, Chen L, Ma S, Xu H, Chen K, Li G. Bombyx mori Flap endonuclease 1 correlates with the repair of ultraviolet-induced DNA damage. JOURNAL OF INSECT PHYSIOLOGY 2022; 142:104424. [PMID: 35878701 DOI: 10.1016/j.jinsphys.2022.104424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
Solar ultraviolet radiation (UV) can cause DNA damage in microorganisms. Flap endonuclease 1 (FEN1) is a structure-specific nuclease and plays important roles in DNA replication and repair. At present, the properties and functions of FEN1 have not been characterized in detail in invertebrates such as Bombyx mori. In this study, Bombyx mori FEN1 (BmFEN1) was expressed in E. coli, and was shown to have nuclease activity that nonspecifically cleaved DNA in vitro. However, inside the cell, BmFEN1 did not cleave DNA randomly. Truncated BmFEN1 missing the nuclear localization signal (346-380 aa) still had the nuclease activity, but was no longer precisely localized to the sites of UV-induced DNA damage. It was further found that BmFEN1 favored the faster repair of UV-damaged DNA. The present study will provide a reference for further understanding the functions of BmFEN1 and UV-induced DNA damage repair mechanisms in insects.
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Affiliation(s)
- Qi Tang
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Yue Liu
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Yutong Liu
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Feifei Zhu
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Qian Yu
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Huiqing Chen
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Liang Chen
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Shangshang Ma
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Huixin Xu
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China
| | - Keping Chen
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China.
| | - Guohui Li
- School of Life Sciences, Jiangsu University, 301# Xuefu Road, Zhenjiang 212013, China.
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Small-Molecule Inhibitors Targeting FEN1 for Cancer Therapy. Biomolecules 2022; 12:biom12071007. [PMID: 35883563 PMCID: PMC9312813 DOI: 10.3390/biom12071007] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/15/2022] [Accepted: 07/19/2022] [Indexed: 01/27/2023] Open
Abstract
DNA damage repair plays a key role in maintaining genomic stability and integrity. Flap endonuclease 1 (FEN1) is a core protein in the base excision repair (BER) pathway and participates in Okazaki fragment maturation during DNA replication. Several studies have implicated FEN1 in the regulation of other DNA repair pathways, including homologous recombination repair (HRR) and non-homologous end joining (NHEJ). Abnormal expression or mutation of FEN1 in cells can cause a series of pathological responses, leading to various diseases, including cancers. Moreover, overexpression of FEN1 contributes to drug resistance in several types of cancers. All this supports the hypothesis that FEN1 could be a therapeutic target for cancer treatment. Targeting FEN1 has been verified as an effective strategy in mono or combined treatment of cancer. Small-molecule compounds targeting FEN1 have also been developed and detected in cancer regression. In this review, we summarize the recent development of small-molecule inhibitors targeting FEN1 in recent years, thereby expanding their therapeutic potential and application.
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Zhang J, Chen M, Pang Y, Cheng M, Huang B, Xu S, Liu M, Lian H, Zhong C. Flap endonuclease 1 and DNA-PKcs synergistically participate in stabilizing replication fork to encounter replication stress in glioma cells. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2022; 41:140. [PMID: 35414100 PMCID: PMC9006432 DOI: 10.1186/s13046-022-02334-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 03/17/2022] [Indexed: 12/15/2022]
Abstract
Background Selectively utilizing alternative mechanisms to repair damaged DNA in essential factors deficient cancer facilitates tumor genetic evolution and contributes to treatment resistance. Synthetic lethality strategies provide a novel scenario to anticancer therapy with DNA repair protein mutation, such as glioma with DNA-PKcs-deficiency, a core factor crucial for non-homologous end joining (NHEJ) mediated DNA damage repair. Nevertheless, the clinical significance and molecular mechanisms of synthetic lethality function by interfering tumor DNA replication remain largely unexplored. Methods Cancer clinic treatment resistance-related replication core factors were identified through bioinformatics analysis and RNA-sequencing and verified in clinical specimens by immunoblotting and in situ Proximity Ligation Analysis (PLA). Then, in vitro and in vivo experiments, including visible single molecular tracking system were performed to determine functional roles, the molecular mechanisms and clinical significance of synthetic lethality on glioma tumors. Results Hyperactive DNA replication and regulator Flap endonuclease 1 (FEN1) provides high efficiency DNA double strand breaks (DSB) repair abilities preventing replication forks collapse during DNA replication which facilitate adaptation to selective pressures. DNA-PKcs deficient glioma cells are highly dependent on FEN1/BRCA1/RAD51 to survival and counteract replication stress. FEN1 protects perturbed forks from erroneous over-resection by MRE11 through regulating of BRCA1-RAD51 and WRN helicase, uncovering an essential genetic interaction between FEN1 and DNA-PKcs in mitigating replication-stress induced tumor genomic instability. Therapeutically, genetic depletion or molecular inhibition of FEN1 and DNA-PKcs perturb glioma progression. Conclusions Our findings highlight an unanticipated synthetic interaction between FEN1/BRCA1/RAD51 and DNA-PKcs when dysfunction leads to incompatible with cell survival under conditions of interrupted replication progression by disrupting addictive alternative tumor evolution and demonstrate the applicability of combined FEN1 and DNA-PKcs targeting in the treatment of glioma. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02334-0.
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Affiliation(s)
- Jing Zhang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China. .,Institute for Advanced Study, Tongji University, 1239 Siping Road, Shanghai, 200092, China.
| | - Mu Chen
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Ying Pang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Meng Cheng
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Bingsong Huang
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Siyi Xu
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Min Liu
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Hao Lian
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China
| | - Chunlong Zhong
- Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, 150 Jimo Road, Shanghai, 200120, China.
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Nickoloff JA, Sharma N, Taylor L, Allen SJ, Hromas R. Nucleases and Co-Factors in DNA Replication Stress Responses. DNA 2022; 2:68-85. [PMID: 36203968 PMCID: PMC9534323 DOI: 10.3390/dna2010006] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
DNA replication stress is a constant threat that cells must manage to proliferate and maintain genome integrity. DNA replication stress responses, a subset of the broader DNA damage response (DDR), operate when the DNA replication machinery (replisome) is blocked or replication forks collapse during S phase. There are many sources of replication stress, such as DNA lesions caused by endogenous and exogenous agents including commonly used cancer therapeutics, and difficult-to-replicate DNA sequences comprising fragile sites, G-quadraplex DNA, hairpins at trinucleotide repeats, and telomeres. Replication stress is also a consequence of conflicts between opposing transcription and replication, and oncogenic stress which dysregulates replication origin firing and fork progression. Cells initially respond to replication stress by protecting blocked replisomes, but if the offending problem (e.g., DNA damage) is not bypassed or resolved in a timely manner, forks may be cleaved by nucleases, inducing a DNA double-strand break (DSB) and providing a means to accurately restart stalled forks via homologous recombination. However, DSBs pose their own risks to genome stability if left unrepaired or misrepaired. Here we focus on replication stress response systems, comprising DDR signaling, fork protection, and fork processing by nucleases that promote fork repair and restart. Replication stress nucleases include MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, and FEN1. Replication stress factors are important in cancer etiology as suppressors of genome instability associated with oncogenic mutations, and as potential cancer therapy targets to enhance the efficacy of chemo- and radiotherapeutics.
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Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Lynn Taylor
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Sage J. Allen
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
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11
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Tsutakawa SE, Bacolla A, Katsonis P, Bralić A, Hamdan SM, Lichtarge O, Tainer JA, Tsai CL. Decoding Cancer Variants of Unknown Significance for Helicase-Nuclease-RPA Complexes Orchestrating DNA Repair During Transcription and Replication. Front Mol Biosci 2021; 8:791792. [PMID: 34966786 PMCID: PMC8710748 DOI: 10.3389/fmolb.2021.791792] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 11/16/2021] [Indexed: 01/13/2023] Open
Abstract
All tumors have DNA mutations, and a predictive understanding of those mutations could inform clinical treatments. However, 40% of the mutations are variants of unknown significance (VUS), with the challenge being to objectively predict whether a VUS is pathogenic and supports the tumor or whether it is benign. To objectively decode VUS, we mapped cancer sequence data and evolutionary trace (ET) scores onto crystallography and cryo-electron microscopy structures with variant impacts quantitated by evolutionary action (EA) measures. As tumors depend on helicases and nucleases to deal with transcription/replication stress, we targeted helicase–nuclease–RPA complexes: (1) XPB-XPD (within TFIIH), XPF-ERCC1, XPG, and RPA for transcription and nucleotide excision repair pathways and (2) BLM, EXO5, and RPA plus DNA2 for stalled replication fork restart. As validation, EA scoring predicts severe effects for most disease mutations, but disease mutants with low ET scores not only are likely destabilizing but also disrupt sophisticated allosteric mechanisms. For sites of disease mutations and VUS predicted to be severe, we found strong co-localization to ordered regions. Rare discrepancies highlighted the different survival requirements between disease and tumor mutations, as well as the value of examining proteins within complexes. In a genome-wide analysis of 33 cancer types, we found correlation between the number of mutations in each tumor and which pathways or functional processes in which the mutations occur, revealing different mutagenic routes to tumorigenesis. We also found upregulation of ancient genes including BLM, which supports a non-random and concerted cancer process: reversion to a unicellular, proliferation-uncontrolled, status by breaking multicellular constraints on cell division. Together, these genes and global analyses challenge the binary “driver” and “passenger” mutation paradigm, support a gradient impact as revealed by EA scoring from moderate to severe at a single gene level, and indicate reduced regulation as well as activity. The objective quantitative assessment of VUS scoring and gene overexpression in the context of functional interactions and pathways provides insights for biology, oncology, and precision medicine.
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Affiliation(s)
- Susan E Tsutakawa
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Albino Bacolla
- Department of Molecular and Cellular Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX, United States
| | - Panagiotis Katsonis
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Amer Bralić
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Samir M Hamdan
- Laboratory of DNA Replication and Recombination, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
| | - Olivier Lichtarge
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - John A Tainer
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.,Department of Molecular and Cellular Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX, United States.,Department of Cancer Biology, University of Texas M.D. Anderson Cancer Center, Houston, TX, United States
| | - Chi-Lin Tsai
- Department of Molecular and Cellular Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX, United States
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12
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Zheng Q, You YL, Li F, Lai QN, Chen JM. Interaction between 038R and 125R of Cherax quadricarinatus iridovirus (CQIV) and their effects on virus replication. J Invertebr Pathol 2021; 187:107699. [PMID: 34838791 DOI: 10.1016/j.jip.2021.107699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 11/15/2021] [Accepted: 11/22/2021] [Indexed: 11/28/2022]
Abstract
Iridovirids are a group icosahedral viruses containing linear double-stranded DNA, and mainly infect invertebrates and poikilothermic vertebrates. Cherax quadricarinatus iridovirus (CQIV) is a new species of the family Iridoviridae and can cause high mortality in shrimps. In CQIV genome, there are 25 conserved genes and the putative products are involved in several viral processes. In this study, three core protein including CQIV-032R, CQIV-125R and CQIV-160L were identified to interact with CQIV-038R by yeast two-hybrid (Y2H), and the interaction between CQIV-038R and CQIV-125R was further confirmed by co-immunoprecipitation (Co-IP) assays. In the expression system, EGFP-038R and mCherry-125R were colocalized in the cytoplasm when co-expressed in Sf9 cells. Moreover, silencing the expression of 038R, 125R or both of these two proteins respectively in C. quadricarinatus cells by small interfering RNAs showed significantly inhibit CQIV replication. Collectively, we identified the interaction between 038R and 125R, and demonstrated they are essential for CQIV replication.
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Affiliation(s)
- Qin Zheng
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Yan-Lin You
- College of Biological Sciences and Engineering, Fuzhou University, Fuzhou 350108, China
| | - Fang Li
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen 361005, China
| | - Qing-Na Lai
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China
| | - Jian-Ming Chen
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China.
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13
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Wilson DM, Deacon AM, Duncton MAJ, Pellicena P, Georgiadis MM, Yeh AP, Arvai AS, Moiani D, Tainer JA, Das D. Fragment- and structure-based drug discovery for developing therapeutic agents targeting the DNA Damage Response. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 163:130-142. [PMID: 33115610 PMCID: PMC8666131 DOI: 10.1016/j.pbiomolbio.2020.10.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/13/2020] [Accepted: 10/23/2020] [Indexed: 12/12/2022]
Abstract
Cancer will directly affect the lives of over one-third of the population. The DNA Damage Response (DDR) is an intricate system involving damage recognition, cell cycle regulation, DNA repair, and ultimately cell fate determination, playing a central role in cancer etiology and therapy. Two primary therapeutic approaches involving DDR targeting include: combinatorial treatments employing anticancer genotoxic agents; and synthetic lethality, exploiting a sporadic DDR defect as a mechanism for cancer-specific therapy. Whereas, many DDR proteins have proven "undruggable", Fragment- and Structure-Based Drug Discovery (FBDD, SBDD) have advanced therapeutic agent identification and development. FBDD has led to 4 (with ∼50 more drugs under preclinical and clinical development), while SBDD is estimated to have contributed to the development of >200, FDA-approved medicines. Protein X-ray crystallography-based fragment library screening, especially for elusive or "undruggable" targets, allows for simultaneous generation of hits plus details of protein-ligand interactions and binding sites (orthosteric or allosteric) that inform chemical tractability, downstream biology, and intellectual property. Using a novel high-throughput crystallography-based fragment library screening platform, we screened five diverse proteins, yielding hit rates of ∼2-8% and crystal structures from ∼1.8 to 3.2 Å. We consider current FBDD/SBDD methods and some exemplary results of efforts to design inhibitors against the DDR nucleases meiotic recombination 11 (MRE11, a.k.a., MRE11A), apurinic/apyrimidinic endonuclease 1 (APE1, a.k.a., APEX1), and flap endonuclease 1 (FEN1).
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Affiliation(s)
- David M Wilson
- Hasselt University, Biomedical Research Institute, Diepenbeek, Belgium; Boost Scientific, Heusden-Zolder, Belgium; XPose Therapeutics Inc., San Carlos, CA, USA
| | - Ashley M Deacon
- Accelero Biostructures Inc., San Francisco, CA, USA; XPose Therapeutics Inc., San Carlos, CA, USA
| | | | | | - Millie M Georgiadis
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, USA; XPose Therapeutics Inc., San Carlos, CA, USA
| | - Andrew P Yeh
- Accelero Biostructures Inc., San Francisco, CA, USA
| | - Andrew S Arvai
- Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Davide Moiani
- Department of Cancer Biology, MD Anderson Cancer Center, Houston, TX, USA; Department of Molecular and Cellular Oncology, MD Anderson Cancer Center, Houston, TX, USA
| | - John A Tainer
- Department of Cancer Biology, MD Anderson Cancer Center, Houston, TX, USA; Department of Molecular and Cellular Oncology, MD Anderson Cancer Center, Houston, TX, USA
| | - Debanu Das
- Accelero Biostructures Inc., San Francisco, CA, USA; XPose Therapeutics Inc., San Carlos, CA, USA.
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14
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Willaume S, Rass E, Fontanilla-Ramirez P, Moussa A, Wanschoor P, Bertrand P. A Link between Replicative Stress, Lamin Proteins, and Inflammation. Genes (Basel) 2021; 12:genes12040552. [PMID: 33918867 PMCID: PMC8070205 DOI: 10.3390/genes12040552] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 03/23/2021] [Accepted: 04/08/2021] [Indexed: 12/12/2022] Open
Abstract
Double-stranded breaks (DSB), the most toxic DNA lesions, are either a consequence of cellular metabolism, programmed as in during V(D)J recombination, or induced by anti-tumoral therapies or accidental genotoxic exposure. One origin of DSB sources is replicative stress, a major source of genome instability, especially when the integrity of the replication forks is not properly guaranteed. To complete stalled replication, restarting the fork requires complex molecular mechanisms, such as protection, remodeling, and processing. Recently, a link has been made between DNA damage accumulation and inflammation. Indeed, defects in DNA repair or in replication can lead to the release of DNA fragments in the cytosol. The recognition of this self-DNA by DNA sensors leads to the production of inflammatory factors. This beneficial response activating an innate immune response and destruction of cells bearing DNA damage may be considered as a novel part of DNA damage response. However, upon accumulation of DNA damage, a chronic inflammatory cellular microenvironment may lead to inflammatory pathologies, aging, and progression of tumor cells. Progress in understanding the molecular mechanisms of DNA damage repair, replication stress, and cytosolic DNA production would allow to propose new therapeutical strategies against cancer or inflammatory diseases associated with aging. In this review, we describe the mechanisms involved in DSB repair, the replicative stress management, and its consequences. We also focus on new emerging links between key components of the nuclear envelope, the lamins, and DNA repair, management of replicative stress, and inflammation.
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15
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A bibliometric analysis of researches on flap endonuclease 1 from 2005 to 2019. BMC Cancer 2021; 21:374. [PMID: 33827468 PMCID: PMC8028219 DOI: 10.1186/s12885-021-08101-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2020] [Accepted: 03/24/2021] [Indexed: 12/21/2022] Open
Abstract
Background Flap endonuclease 1 (FEN1) is a structure-specific nuclease that plays a role in a variety of DNA metabolism processes. FEN1 is important for maintaining genomic stability and regulating cell growth and development. It is associated with the occurrence and development of several diseases, especially cancers. There is a lack of systematic bibliometric analyses focusing on research trends and knowledge structures related to FEN1. Purpose To analyze hotspots, the current state and research frontiers performed for FEN1 over the past 15 years. Methods Publications were retrieved from the Web of Science Core Collection (WoSCC) database, analyzing publication dates ranging from 2005 to 2019. VOSviewer1.6.15 and Citespace5.7 R1 were used to perform a bibliometric analysis in terms of countries, institutions, authors, journals and research areas related to FEN1. A total of 421 publications were included in this analysis. Results Our findings indicated that FEN1 has received more attention and interest from researchers in the past 15 years. Institutes in the United States, specifically the Beckman Research Institute of City of Hope published the most research related to FEN1. Shen BH, Zheng L and Bambara Ra were the most active researchers investigating this endonuclease and most of this research was published in the Journal of Biological Chemistry. The main scientific areas of FEN1 were related to biochemistry, molecular biology, cell biology, genetics and oncology. Research hotspots included biological activities, DNA metabolism mechanisms, protein-protein interactions and gene mutations. Research frontiers included oxidative stress, phosphorylation and tumor progression and treatment. Conclusion This bibliometric study may aid researchers in the understanding of the knowledge base and research frontiers associated with FEN1. In addition, emerging hotspots for research can be used as the subjects of future studies.
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16
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Zhou X, Chen X, An Y, Lu H, Wang L, Xu H, Tian B, Zhao Y, Hua Y. Biochemical characterization of a unique DNA polymerase A from the extreme radioresistant organism Deinococcus radiodurans. Biochimie 2021; 185:22-32. [PMID: 33727139 DOI: 10.1016/j.biochi.2021.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 01/30/2021] [Accepted: 02/19/2021] [Indexed: 01/07/2023]
Abstract
Deinococcus radiodurans survives extraordinary doses of ionizing radiation and desiccation that cause numerous DNA strand breaks. D. radiodurans DNA polymerase A (DrPolA) is essential for reassembling the shattered genome, while its biochemical property has not been fully demonstrated. In this study, we systematically examined the enzymatic activities of DrPolA and characterized its unique features. DrPolA contains an N-terminal nuclease domain (DrPolA-NTD) and a C-terminal Klenow fragment (KlenDr). Compared with the Klenow fragment of E. coli Pol I, KlenDr shows higher fidelity despite the lacking of 3'-5' exonuclease proofreading activity and prefers double-strand DNA rather than Primer-Template substrates. Apart from the well-annotated 5'-3' exonuclease and flap endonuclease activities, DrPolA-NTD displays approximately 140-fold higher gap endonuclease activity than its homolog in E. coli and Human FEN1. Its 5'-3' exonuclease activity on ssDNA, gap endonuclease, and Holliday junction cleavage activities are greatly enhanced by Mn2+. The DrPolA-NTD deficient strain shows increased sensitivity to UV and gamma-ray radiation. Collectively, our results reveal distinct biochemical characteristics of DrPolA during DNA degradation and re-synthesis, which provide new insight into the outstanding DNA repair capacity of D. radiodurans.
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Affiliation(s)
- Xingru Zhou
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Xuanyi Chen
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Ying An
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Huizhi Lu
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Liangyan Wang
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Hong Xu
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Bing Tian
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Ye Zhao
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China
| | - Yuejin Hua
- The MOE Key Laboratory of Biosystems Homeostasis & Protection, Institute of Biophysics, College of Life Sciences, Zhejiang University, China.
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Pauszek RF, Lamichhane R, Rajkarnikar Singh A, Millar DP. Single-molecule view of coordination in a multi-functional DNA polymerase. eLife 2021; 10:e62046. [PMID: 33704066 PMCID: PMC7952088 DOI: 10.7554/elife.62046] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 12/28/2020] [Indexed: 01/01/2023] Open
Abstract
Replication and repair of genomic DNA requires the actions of multiple enzymatic functions that must be coordinated in order to ensure efficient and accurate product formation. Here, we have used single-molecule FRET microscopy to investigate the physical basis of functional coordination in DNA polymerase I (Pol I) from Escherichia coli, a key enzyme involved in lagging-strand replication and base excision repair. Pol I contains active sites for template-directed DNA polymerization and 5' flap processing in separate domains. We show that a DNA substrate can spontaneously transfer between polymerase and 5' nuclease domains during a single encounter with Pol I. Additionally, we show that the flexibly tethered 5' nuclease domain adopts different positions within Pol I-DNA complexes, depending on the nature of the DNA substrate. Our results reveal the structural dynamics that underlie functional coordination in Pol I and are likely relevant to other multi-functional DNA polymerases.
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Affiliation(s)
- Raymond F Pauszek
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
| | - Rajan Lamichhane
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
| | - Arishma Rajkarnikar Singh
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
| | - David P Millar
- Department of Integrative Structural and Computational Biology, The Scripps Research InstituteLa JollaUnited States
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18
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Schilling EM, Scherer M, Rothemund F, Stamminger T. Functional regulation of the structure-specific endonuclease FEN1 by the human cytomegalovirus protein IE1 suggests a role for the re-initiation of stalled viral replication forks. PLoS Pathog 2021; 17:e1009460. [PMID: 33770148 PMCID: PMC8026080 DOI: 10.1371/journal.ppat.1009460] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 04/07/2021] [Accepted: 03/08/2021] [Indexed: 11/19/2022] Open
Abstract
Flap endonuclease 1 (FEN1) is a member of the family of structure-specific endonucleases implicated in regulation of DNA damage response and DNA replication. So far, knowledge on the role of FEN1 during viral infections is limited. Previous publications indicated that poxviruses encode a conserved protein that acts in a manner similar to FEN1 to stimulate homologous recombination, double-strand break (DSB) repair and full-size genome formation. Only recently, cellular FEN1 has been identified as a key component for hepatitis B virus cccDNA formation. Here, we report on a novel functional interaction between Flap endonuclease 1 (FEN1) and the human cytomegalovirus (HCMV) immediate early protein 1 (IE1). Our results provide evidence that IE1 manipulates FEN1 in an unprecedented manner: we observed that direct IE1 binding does not only enhance FEN1 protein stability but also phosphorylation at serine 187. This correlates with nucleolar exclusion of FEN1 stimulating its DSB-generating gap endonuclease activity. Depletion of FEN1 and inhibition of its enzymatic activity during HCMV infection significantly reduced nascent viral DNA synthesis demonstrating a supportive role for efficient HCMV DNA replication. Furthermore, our results indicate that FEN1 is required for the formation of DSBs during HCMV infection suggesting that IE1 acts as viral activator of FEN1 in order to re-initiate stalled replication forks. In summary, we propose a novel mechanism of viral FEN1 activation to overcome replication fork barriers at difficult-to-replicate sites in viral genomes.
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Affiliation(s)
| | - Myriam Scherer
- Institute of Virology, Ulm University Medical Center, Ulm, Germany
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19
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Xu L, Shen JM, Qu JL, Song N, Che XF, Hou KZ, Shi J, Zhao L, Shi S, Liu YP, Qu XJ, Teng YE. FEN1 is a prognostic biomarker for ER+ breast cancer and associated with tamoxifen resistance through the ERα/cyclin D1/Rb axis. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:258. [PMID: 33708885 PMCID: PMC7940940 DOI: 10.21037/atm-20-3068] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Background Tamoxifen is an important choice in endocrine therapy for patients with oestrogen receptor-positive (ER+) breast cancer, and disease progression-associated resistance to tamoxifen therapy is still challenging. Flap endonuclease-1 (FEN1) is used as a prognostic biomarker and is considered to participate in proliferation, migration, and drug resistance in multiple cancers, especially breast cancer, but the prognostic function of FEN1 in ER+ breast cancer, and whether FEN1 is related to tamoxifen resistance or not, remain to be explored. Methods On-line database Kaplan-Meier (KM) plotter, GEO datasets, and immunohistochemistry were used to analyse the prognostic value of FEN1 in ER+ breast cancer from mRNA and protein levels. Cell viability assay and colony formation assays showed the response of tamoxifen in MCF-7 and T47D cells. Microarray data with FEN1 siRNA versus control group in MCF-7 cells were analysed by Gene Set Enrichment Analysis (GSEA). The protein levels downstream of FEN1 were detected by western blot assay. Results ER+ breast cancer patients who received tamoxifen for adjuvant endocrine therapy with poor prognosis showed a high expression of FEN1. MCF-7 and T47D appeared resistant to tamoxifen after FEN1 over-expression and increased sensitivity to tamoxifen after FEN1 knockdown. Importantly, FEN1 over-expression could activate tamoxifen resistance through the ERα/cyclin D1/Rb axis. Conclusions As a biomarker of tamoxifen effectiveness, FEN1 participates in tamoxifen resistance through ERα/cyclin D1/Rb axis. In the future, reversing tamoxifen resistance by knocking-down FEN1 or by way of action as a small molecular inhibitor of FEN1 warrants further investigation.
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Affiliation(s)
- Lu Xu
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Ji-Ming Shen
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Jing-Lei Qu
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Na Song
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Xiao-Fang Che
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Ke-Zuo Hou
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Jing Shi
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Lei Zhao
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Sha Shi
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Yun-Peng Liu
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Xiu-Juan Qu
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
| | - Yue-E Teng
- Department of Medical Oncology, the First Hospital of China Medical University, Shenyang, China.,Key Laboratory of Anticancer Drugs and Biotherapy of Liaoning Province, the First Hospital of China Medical University, Shenyang, China
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20
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Shi R, Wang Y, Gao Y, Xu X, Mao S, Xiao Y, Song S, Wang L, Tian B, Zhao Y, Hua Y, Xu H. Succinylation at a key residue of FEN1 is involved in the DNA damage response to maintain genome stability. Am J Physiol Cell Physiol 2020; 319:C657-C666. [PMID: 32783654 DOI: 10.1152/ajpcell.00137.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human flap endonuclease 1 (FEN1) is a structure-specific, multifunctional endonuclease essential for DNA replication and repair. Our previous study showed that in response to DNA damage, FEN1 interacts with the PCNA-like Rad9-Rad1-Hus1 complex instead of PCNA to engage in DNA repair activities, such as stalled DNA replication fork repair, and undergoes SUMOylation by SUMO-1. Here, we report that succinylation of FEN1 was stimulated in response to DNA replication fork-stalling agents, such as ultraviolet (UV) irradiation, hydroxyurea, camptothecin, and mitomycin C. K200 is a key succinylation site of FEN1 that is essential for gap endonuclease activity and could be suppressed by methylation and stimulated by phosphorylation to promote SUMO-1 modification. Succinylation at K200 of FEN1 promoted the interaction of FEN1 with the Rad9-Rad1-Hus1 complex to rescue stalled replication forks. Impairment of FEN1 succinylation led to the accumulation of DNA damage and heightened sensitivity to fork-stalling agents. Altogether, our findings suggest an important role of FEN1 succinylation in regulating its roles in DNA replication and repair, thus maintaining genome stability.
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Affiliation(s)
- Rongyi Shi
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Yiyi Wang
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Ya Gao
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Xiaoli Xu
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Shuyu Mao
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Yue Xiao
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Shuang Song
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Liangyan Wang
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Bing Tian
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Ye Zhao
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Yuejin Hua
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
| | - Hong Xu
- MOE Key Laboratory of Biosystems Homeostasis and Protection, Institute of Biophysics, College of Life Science, Zhejiang University, Hangzhou, China
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21
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Karakaidos P, Karagiannis D, Rampias T. Resolving DNA Damage: Epigenetic Regulation of DNA Repair. Molecules 2020; 25:molecules25112496. [PMID: 32471288 PMCID: PMC7321228 DOI: 10.3390/molecules25112496] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 12/18/2022] Open
Abstract
Epigenetic research has rapidly evolved into a dynamic field of genome biology. Chromatin regulation has been proved to be an essential aspect for all genomic processes, including DNA repair. Chromatin structure is modified by enzymes and factors that deposit, erase, and interact with epigenetic marks such as DNA and histone modifications, as well as by complexes that remodel nucleosomes. In this review we discuss recent advances on how the chromatin state is modulated during this multi-step process of damage recognition, signaling, and repair. Moreover, we examine how chromatin is regulated when different pathways of DNA repair are utilized. Furthermore, we review additional modes of regulation of DNA repair, such as through the role of global and localized chromatin states in maintaining expression of DNA repair genes, as well as through the activity of epigenetic enzymes on non-nucleosome substrates. Finally, we discuss current and future applications of the mechanistic interplays between chromatin regulation and DNA repair in the context cancer treatment.
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Affiliation(s)
| | - Dimitris Karagiannis
- Department of Genetics and Development, Columbia University Medical Center, New York, NY 10032, USA;
| | - Theodoros Rampias
- Biomedical Research Foundation of the Academy of Athens, 11527 Athens, Greece;
- Correspondence: ; Tel.: +30-210-659-7469
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22
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Witkin AE, Banerji J, Bullock PA. A model for the formation of the duplicated enhancers found in polyomavirus regulatory regions. Virology 2020; 543:27-33. [PMID: 32056844 DOI: 10.1016/j.virol.2020.01.013] [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: 01/09/2020] [Revised: 01/27/2020] [Accepted: 01/27/2020] [Indexed: 12/14/2022]
Abstract
When purified from persistent infections, the genomes of most human polyomaviruses contain single enhancers. However, when isolated from productively infected cells from immunocompromised individuals, the genomes of several polyomaviruses contain duplicated enhancers that promote a number of polyoma-based diseases. The mechanism(s) that gives rise to the duplicated enhancers in the polyomaviruses is, however, not known. Herein we propose a model for the duplication of the enhancers that is based on recent advances in our understanding of; 1) the initiation of polyomavirus DNA replication, 2) the formation of long flaps via displacement synthesis and 3) the subsequent generation of duplicated enhancers via double stranded break repair. Finally, we discuss the possibility that the polyomavirus based replication dependent enhancer duplication model may be relevant to the enhancer-associated rearrangements detected in human genomes that are associated with various diseases, including cancers.
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Affiliation(s)
- Anna E Witkin
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, 02111, USA
| | - Julian Banerji
- Center for Computational and Integrative Biology, Simches Research Center, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA, 02114, USA
| | - Peter A Bullock
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA, 02111, USA.
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23
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Xu X, Shi R, Zheng L, Guo Z, Wang L, Zhou M, Zhao Y, Tian B, Truong K, Chen Y, Shen B, Hua Y, Xu H. SUMO-1 modification of FEN1 facilitates its interaction with Rad9-Rad1-Hus1 to counteract DNA replication stress. J Mol Cell Biol 2019; 10:460-474. [PMID: 30184152 PMCID: PMC6231531 DOI: 10.1093/jmcb/mjy047] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 09/03/2018] [Indexed: 01/25/2023] Open
Abstract
Human flap endonuclease 1 (FEN1) is a structure-specific, multi-functional endonuclease essential for DNA replication and repair. We and others have shown that during DNA replication, FEN1 processes Okazaki fragments via its interaction with the proliferating cell nuclear antigen (PCNA). Alternatively, in response to DNA damage, FEN1 interacts with the PCNA-like Rad9–Rad1–Hus1 complex instead of PCNA to engage in DNA repair activities, such as homology-directed repair of stalled DNA replication forks. However, it is unclear how FEN1 is able to switch between these interactions and its roles in DNA replication and DNA repair. Here, we report that FEN1 undergoes SUMOylation by SUMO-1 in response to DNA replication fork-stalling agents, such as UV irradiation, hydroxyurea, and mitomycin C. This DNA damage-induced SUMO-1 modification promotes the interaction of FEN1 with the Rad9–Rad1–Hus1 complex. Furthermore, we found that FEN1 mutations that prevent its SUMO-1 modification also impair its ability to interact with HUS1 and to rescue stalled replication forks. These impairments lead to the accumulation of DNA damage and heightened sensitivity to fork-stalling agents. Altogether, our findings suggest an important role of the SUMO-1 modification of FEN1 in regulating its roles in DNA replication and repair.
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Affiliation(s)
- Xiaoli Xu
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Rongyi Shi
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA, USA
| | - Zhigang Guo
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology and College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Liangyan Wang
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Mian Zhou
- Department of Cancer Genetics and Epigenetics, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA, USA
| | - Ye Zhao
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Bing Tian
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Khue Truong
- Department of Molecular Medicine, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA, USA
| | - Yuan Chen
- Department of Molecular Medicine, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA, USA
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA, USA
| | - Yuejin Hua
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Hong Xu
- Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
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24
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Xu H, Shi R, Han W, Cheng J, Xu X, Cheng K, Wang L, Tian B, Zheng L, Shen B, Hua Y, Zhao Y. Structural basis of 5' flap recognition and protein-protein interactions of human flap endonuclease 1. Nucleic Acids Res 2019; 46:11315-11325. [PMID: 30295841 PMCID: PMC6265464 DOI: 10.1093/nar/gky911] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 10/06/2018] [Indexed: 01/30/2023] Open
Abstract
Human flap endonuclease 1 (hFEN1) is a structure-specific nuclease essential for DNA replication and repair processes. hFEN1 has 5′ flap removal activity, as well as gap endonuclease activity that is critical for restarting stalled replication forks. Here, we report the crystal structures of wild-type and mutant hFEN1 proteins in complex with DNA substrates, followed by mutagenesis studies that provide mechanistic insight into the protein–protein interactions of hFEN1. We found that in an α-helix forming the helical gateway of hFEN1 recognizes the 5′ flap prior to its threading into the active site for cleavage. We also found that the β-pin region is rigidified into a short helix in R192F hFEN1–DNA structures, suppressing its gap endonuclease activity and cycle-dependent kinase interactions. Our findings suggest that a single mutation at the primary methylation site can alter the function of hFEN1 and provide insight into the role of the β-pin region in hFEN1 protein interactions that are essential for DNA replication and repair.
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Affiliation(s)
- Hong Xu
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Rongyi Shi
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Wanchun Han
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Jiahui Cheng
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Xiaoli Xu
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Kaiying Cheng
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Liangyan Wang
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Bing Tian
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA 91010, USA
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics, City of Hope National Medical Center and Beckman Research Institute, Duarte, CA 91010, USA
| | - Yuejin Hua
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
| | - Ye Zhao
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, Zhejiang 310029, China
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25
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Moazeni-Roodi A, Ghavami S, Ansari H, Hashemi M. Association between the flap endonuclease 1 gene polymorphisms and cancer susceptibility: An updated meta-analysis. J Cell Biochem 2019; 120:13583-13597. [PMID: 30937972 DOI: 10.1002/jcb.28633] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/28/2019] [Accepted: 02/14/2019] [Indexed: 11/10/2022]
Abstract
Flap endonuclease 1 (FEN1) has emerged as an important enzyme in the maintenance of genomic instability and preventing carcinogenesis. The relationship between FEN1 -69G>A (rs174538)+4150G>T (rs4246215) polymorphisms and cancer susceptibility has been reported; however, results were inconclusive. In the present study, a meta-analysis of data from eligible reports was carried out to summarize the possible relationship between FEN1 polymorphisms and cancer risk. A total of 11 articles, including 20 studies with 7366 cases and 9028 controls and 18 studies with 6649 cases and 8325 controls for FEN1 rs174538 and FEN1 rs4246215 polymorphisms, respectively, were recruited for meta-analysis. Overall, meta-analyses showed that FEN1 rs174538 and rs4246215 polymorphisms are significantly associated with the decreased risk of cancer. The stratified analysis proposed that both variants were associated with protection against gastrointestinal cancer, breast cancer, hepatocellular cancer, esophageal cancer, gastric cancer, colorectal cancer, and lung cancer. In conclusion, this meta-analysis revealed an association between FEN1 polymorphisms and cancer risk. Additional studies in a larger study population that include subjects from a variety of ethnicities are warranted to further verify our findings.
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Affiliation(s)
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada.,Research Institute in Oncology and Hematology, CancerCare Manitoba, University of Manitoba, Winnipeg, Canada
| | - Hossein Ansari
- Department of Epidemiology and Biostatistics, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Mohammad Hashemi
- Genetics of Non-communicable Disease Research Center, Zahedan University of Medical Sciences, Zahedan, Iran.,Department of Clinical Biochemistry, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran
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26
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Kim SM, Forsburg SL. Regulation of Structure-Specific Endonucleases in Replication Stress. Genes (Basel) 2018; 9:genes9120634. [PMID: 30558228 PMCID: PMC6316474 DOI: 10.3390/genes9120634] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 12/11/2018] [Accepted: 12/12/2018] [Indexed: 12/16/2022] Open
Abstract
Replication stress results in various forms of aberrant replication intermediates that need to be resolved for faithful chromosome segregation. Structure-specific endonucleases (SSEs) recognize DNA secondary structures rather than primary sequences and play key roles during DNA repair and replication stress. Holliday junction resolvase MUS81 (methyl methane sulfonate (MMS), and UV-sensitive protein 81) and XPF (xeroderma pigmentosum group F-complementing protein) are a subset of SSEs that resolve aberrant replication structures. To ensure genome stability and prevent unnecessary DNA breakage, these SSEs are tightly regulated by the cell cycle and replication checkpoints. We discuss the regulatory network that control activities of MUS81 and XPF and briefly mention other SSEs involved in the resolution of replication intermediates.
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Affiliation(s)
- Seong Min Kim
- Program in Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90089, USA.
| | - Susan L Forsburg
- Program in Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90089, USA.
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27
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Lu R, Wang Y, Xu X, Xie S, Wang Y, Zhong A, Zheng H, Yu Y, Gao X, Guo L. Establishment of a detection assay for DNA endonuclease activity and its application in the screening and prognosis of malignant lymphoma. BMC BIOCHEMISTRY 2018; 19:6. [PMID: 30064372 PMCID: PMC6069817 DOI: 10.1186/s12858-018-0096-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 07/20/2018] [Indexed: 11/29/2022]
Abstract
BACKGROUND Endonucleases play critical roles in maintaining genomic stability and regulating cell growth. The purpose of this study was to evaluate detection of endonuclease activity as an indicator in the early diagnosis and prognosis of lymphoma. RESULTS The method of endonuclease activity determination was successfully established and applied to compare cancer patient and control cohorts. Endonuclease activities of cancer tissues were significantly higher than those of adjacent control tissues (P < 0.001). We next investigated endonuclease activity in peripheral blood of enrolled patients and the controls, which were also significantly higher in patients than in controls (P = 0.015). Additionally, endonuclease activities were elevated in the metastasis subgroup compared with the non-metastasis subgroup(P = 0.038), whereas no significant difference was found between age(≤ 56y, > 56y) and gender (P = 0.736 > 0.05 and P = 0.635 > 0.05, respectively). Although there was no significant difference between control group with the non-metastatic cancer patients (P = 0.800 > 0.05), endonuclease activities were lower in the control group compared with the non-metastatic cancer patients with lymphoma (P = 0.033). The progression-free survival probability of patients with elevated R ratios(R ratio ≥ 1.4) was significantly lower than that of patients with lower R ratios (R ratio < 1.4). CONCLUSIONS An assay was established to detect the endonuclease activity,which might be useful for the prognosis of cancers, especially lymphoma.
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Affiliation(s)
- Renquan Lu
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Yingchao Wang
- Department of Clinical Laboratory, Shanghai Proton and Heavy Ion Center, Shanghai, 201321 China
| | - Xiaofeng Xu
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
- Department of Clinical Laboratory, Shanghai Proton and Heavy Ion Center, Shanghai, 201321 China
| | - Suhong Xie
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Yanchun Wang
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Ailing Zhong
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Hui Zheng
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Yiwen Yu
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Xiang Gao
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
| | - Lin Guo
- Department of Clinical Laboratory, Fudan University Shanghai Cancer Center, 270 DongAn Road, Xuhui District, Shanghai, 200032 China
- Department of Clinical Laboratory, Shanghai Proton and Heavy Ion Center, Shanghai, 201321 China
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28
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Pasero P, Vindigni A. Nucleases Acting at Stalled Forks: How to Reboot the Replication Program with a Few Shortcuts. Annu Rev Genet 2018; 51:477-499. [PMID: 29178820 DOI: 10.1146/annurev-genet-120116-024745] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In a lifetime, a human being synthesizes approximately 2×1016 meters of DNA, a distance that corresponds to 130,000 times the distance between the Earth and the Sun. This daunting task is executed by thousands of replication forks, which progress along the chromosomes and frequently stall when they encounter DNA lesions, unusual DNA structures, RNA polymerases, or tightly-bound protein complexes. To complete DNA synthesis before the onset of mitosis, eukaryotic cells have evolved complex mechanisms to process and restart arrested forks through the coordinated action of multiple nucleases, topoisomerases, and helicases. In this review, we discuss recent advances in understanding the role and regulation of nucleases acting at stalled forks with a focus on the nucleolytic degradation of nascent DNA, a process commonly referred to as fork resection. We also discuss the effects of deregulated fork resection on genomic instability and on the unscheduled activation of the interferon response under replication stress conditions.
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Affiliation(s)
- Philippe Pasero
- Institute of Human Genetics, CNRS UMR9002, University of Montpellier, 34396 Montpellier, France;
| | - Alessandro Vindigni
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, Missouri 63104, USA;
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29
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Watanabe T, Tanaka H, Horiuchi T. Complex repeat structure promotes hyper-amplification and amplicon evolution through rolling-circle replication. Nucleic Acids Res 2018; 46:5097-5108. [PMID: 29718479 PMCID: PMC6007334 DOI: 10.1093/nar/gky275] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 04/04/2018] [Indexed: 11/30/2022] Open
Abstract
Inverted repeats (IRs) are abundant in genomes and frequently serve as substrates for chromosomal aberrations, including gene amplification. In the early stage of amplification, repeated cycles of chromosome breakage and rearrangement, called breakage-fusion-bridge (BFB), generate a large inverted structure, which evolves into highly-amplified, complex end products. However, it remains to be determined how IRs mediate chromosome rearrangements and promote subsequent hyper-amplification and amplicon evolutions. To dissect the complex processes, we constructed repetitive structures in a yeast chromosome and selected amplified cells using genetic markers with limited expression. The genomic architecture was associated with replication stress and produced extra-/intra-chromosomal amplification. Genetic analysis revealed structure-specific endonucleases, Mus81 and Rad27, and post-replication DNA repair protein, Rad18, suppress the amplification processes. Following BFB cycles, the intra-chromosomal products undergo intensive rearrangements, such as frequent inversions and deletions, indicative of rolling-circle replication. This study presents an integrated view linking BFB cycles to hyper-amplification driven by rolling-circle replication.
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Affiliation(s)
- Takaaki Watanabe
- Department of Molecular Life Science, Division of Basic Molecular Science and Molecular Medicine, School of Medicine, Tokai University, Isehara, Kanagawa, Japan.,Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Molecular Genetics, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA.,National Institute for Basic Biology, Okazaki, Aichi, Japan
| | - Hisashi Tanaka
- Department of Surgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.,Department of Molecular Genetics, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA.,Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA
| | - Takashi Horiuchi
- Department of Molecular Life Science, Division of Basic Molecular Science and Molecular Medicine, School of Medicine, Tokai University, Isehara, Kanagawa, Japan.,National Institute for Basic Biology, Okazaki, Aichi, Japan
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30
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Lee CC, Hsieh TS. Wuho/WDR4 deficiency inhibits cell proliferation and induces apoptosis via DNA damage in mouse embryonic fibroblasts. Cell Signal 2018; 47:16-26. [PMID: 29574139 DOI: 10.1016/j.cellsig.2018.03.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 03/16/2018] [Accepted: 03/19/2018] [Indexed: 12/27/2022]
Abstract
Wuho known as WDR4 encodes a highly conserved WD40-repeat protein, which has known homologues of WDR4 in human and mouse. Wuho-FEN1 interaction may have a critical role in the growth and development, and in the maintenance of genome stability. However, how Wuho gene deletion contributes to cell growth inhibition and apoptosis is still unknown. We utilized CAGGCre-ER transgenic mice have a tamoxifen-inducible cre-mediated recombination cassette to prepare primary mouse embryonic fibroblasts (MEFs) with Wuho deficiency. We have demonstrated that Wuho deficiency would induces γH2AX protein level elevation, heterochromatin relaxation and DNA damage down-stream sequences, including p53 activation, caspase-mediated apoptotic pathway, and p21-mediated G2/M cell cycle arrest.
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Affiliation(s)
- Chi-Chiu Lee
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Sec. 2, Nangang, Taipei 11529, Taiwan.
| | - Tao-Shih Hsieh
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Academia Road, Sec. 2, Nangang, Taipei 11529, Taiwan; Department of Biochemistry, Duke University, Durham, NC, United States
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31
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Chou AK, Shen MY, Chen FY, Hsiao CL, Shih LC, Chang WS, Tsai CW, Ying TH, Wu MH, Huang CY, Bau DAT. The Association of Flap Endonuclease 1 Genotypes with the Susceptibility of Endometriosis. Cancer Genomics Proteomics 2017; 14:455-460. [PMID: 29109095 DOI: 10.21873/cgp.20055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 09/05/2017] [Accepted: 10/06/2017] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND/AIM Flap endonuclease 1 (FEN1), a protein with multiple functions in genome stability maintenance, is important in cancer prevention. The two functional germline variants of FEN1, rs174538 and rs4246215, regarding cancer susceptibility have been reported in lung, breast, liver, esophageal, gastric, colorectal cancer, glioma and leukemia, but not endometriosis. In this study, we firstly aimed at evaluating the contribution of FEN1 genotypes to endometriosis risk in a representative Taiwan population. MATERIALS AND METHODS In total, 153 patients with endometriosis and 636 non-cancer healthy controls were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methodology. RESULTS The genotypes of FEN1 rs174538, but not those of rs4246215, were differently distributed between the endometriosis and control groups. In detail, the AA of FEN1 rs174538 genotypes were significantly less frequently found among endometriosis patients than among controls (odds ratio [OR]=0.43, 95% confidence interval [CI]=0.24-0.78, p=0.0125). The A allele at FEN1 rs174538 was also significantly less frequent among cases than controls (OR=0.65, 95%CI=0.50-0.86, p=0.0021). As for age of first menarche, those with first menarche at the age >12.8 carrying the FEN1 rs174538 AA genotype conferred lower OR of 0.29 (95%CI=0.11-0.78, p=0.0381) for endometriosis. Regarding the full pregnancy status, those without having had a full-term pregnancy carrying the FEN1 rs174538 AA genotype were of lower risk (ORs=0.12, 95%CI=0.03-0.53, p=0.0050). CONCLUSION The FEN1 rs174538 A allele is a novel protective biomarker for endometriosis and this genotype may have interactions with age- and hormone-related factors on the development of endometriosis.
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Affiliation(s)
- An-Kuo Chou
- Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Ming-Yi Shen
- Department of Medical Research, China Medical University Hospital, Taichung, Taiwan Hospital, Taichung, Taiwan, R.O.C.,Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan, R.O.C
| | - Fang-Yu Chen
- Department of Medical Research, China Medical University Hospital, Taichung, Taiwan Hospital, Taichung, Taiwan, R.O.C
| | - Chieh-Lun Hsiao
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan, R.O.C.,Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Liang-Chun Shih
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Wen-Shin Chang
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Chia-Wen Tsai
- Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Tsung-Ho Ying
- Department of Obstetrics and Gynecology, Chung Shan Medical University Hospital, Taichung, Taiwan, R.O.C
| | - Ming-Hsien Wu
- Taichung Armed Forces General Hospital, Taichung, Taiwan, R.O.C
| | - Chung-Yu Huang
- Taoyuan Armed Forces General Hospital, Taoyuan, Taiwan, R.O.C
| | - DA-Tian Bau
- Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan, R.O.C. .,Terry Fox Cancer Research Laboratory, China Medical University Hospital, Taichung, Taiwan, R.O.C.,Department of Bioinformatics and Medical Engineering, Asia University, Taichung, Taiwan, R.O.C
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32
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Thandapani P, Couturier AM, Yu Z, Li X, Couture JF, Li S, Masson JY, Richard S. Lysine methylation of FEN1 by SET7 is essential for its cellular response to replicative stress. Oncotarget 2017; 8:64918-64931. [PMID: 29029401 PMCID: PMC5630301 DOI: 10.18632/oncotarget.18070] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 04/18/2017] [Indexed: 12/17/2022] Open
Abstract
The DNA damage response (DDR) is central to the cell survival and it requires post-translational modifications, in part, to sense the damage, amplify the signaling response and recruit and regulate DNA repair enzymes. Lysine methylation of histones such as H4K20 and non-histone proteins including p53 has been shown to be essential for the mounting of the DDR. It is well-known that the lysine methyltransferase SET7 regulates the DDR, as cells lacking this enzyme are hypersensitive to chemotherapeutic drugs. To define addition substrates of SET7 involved in the DDR, we screened a peptide array encompassing potential lysine methylation sites from >100 key DDR proteins and identified peptides from 58 proteins to be lysine methylated defining a methylation consensus sequence of [S>K-2; S>R-1; K0] consistent with previous findings. We focused on K377 methylation of the Flap endonuclease 1 (FEN1), a structure specific endonuclease with important functions in Okazaki fragment processing during DNA replication as a substrate of SET7. FEN1 was monomethylated by SET7 in vivo in a cell cycle dependent manner with levels increasing as cells progressed through S phase and decreasing as they exited S phase, as detected using K377me1 specific antibodies. Although K377me1 did not affect the enzymatic activity of FEN1, it was required for the cellular response to replicative stress by FEN1. These finding define FEN1 as a new substrate of SET7 required for the DDR.
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Affiliation(s)
- Palaniraja Thandapani
- Terry Fox Molecular Oncology Group and Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
- Departments of Oncology and Medicine, McGill University, Montréal, Québec, Canada
| | - Anthony M. Couturier
- Genome Stability Laboratory, Laval University Cancer Research Center, CRCHU de Québec, Québec, Canada
| | - Zhenbao Yu
- Terry Fox Molecular Oncology Group and Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
- Departments of Oncology and Medicine, McGill University, Montréal, Québec, Canada
| | - Xing Li
- Department of Biochemistry, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada
| | - Jean-François Couture
- Ottawa Institute of Systems Biology, Department of Biochemistry, Microbiology, and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Shawn Li
- Genome Stability Laboratory, Laval University Cancer Research Center, CRCHU de Québec, Québec, Canada
| | - Jean-Yves Masson
- Genome Stability Laboratory, Laval University Cancer Research Center, CRCHU de Québec, Québec, Canada
| | - Stéphane Richard
- Terry Fox Molecular Oncology Group and Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
- Departments of Oncology and Medicine, McGill University, Montréal, Québec, Canada
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33
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Ward TA, McHugh PJ, Durant ST. Small molecule inhibitors uncover synthetic genetic interactions of human flap endonuclease 1 (FEN1) with DNA damage response genes. PLoS One 2017. [PMID: 28628639 PMCID: PMC5476263 DOI: 10.1371/journal.pone.0179278] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Flap endonuclease 1 (FEN1) is a structure selective endonuclease required for proficient DNA replication and the repair of DNA damage. Cellularly active inhibitors of this enzyme have previously been shown to induce a DNA damage response and, ultimately, cell death. High-throughput screens of human cancer cell-lines identify colorectal and gastric cell-lines with microsatellite instability (MSI) as enriched for cellular sensitivity to N-hydroxyurea series inhibitors of FEN1, but not the PARP inhibitor olaparib or other inhibitors of the DNA damage response. This sensitivity is due to a synthetic lethal interaction between FEN1 and MRE11A, which is often mutated in MSI cancers through instabilities at a poly(T) microsatellite repeat. Disruption of ATM is similarly synthetic lethal with FEN1 inhibition, suggesting that disruption of FEN1 function leads to the accumulation of DNA double-strand breaks. These are likely a result of the accumulation of aberrant replication forks, that accumulate as a consequence of a failure in Okazaki fragment maturation, as inhibition of FEN1 is toxic in cells disrupted for the Fanconi anemia pathway and post-replication repair. Furthermore, RAD51 foci accumulate as a consequence of FEN1 inhibition and the toxicity of FEN1 inhibitors increases in cells disrupted for the homologous recombination pathway, suggesting a role for homologous recombination in the resolution of damage induced by FEN1 inhibition. Finally, FEN1 appears to be required for the repair of damage induced by olaparib and cisplatin within the Fanconi anemia pathway, and may play a role in the repair of damage associated with its own disruption.
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Affiliation(s)
- Thomas A. Ward
- AstraZeneca, Innovative Medicines and Early Development Biotech Unit, Oncology Bioscience, Alderley Park, Macclesfield, Cheshire, United Kingdom
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
- * E-mail: (TAW); (STD)
| | - Peter J. McHugh
- Department of Oncology, MRC Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom
| | - Stephen T. Durant
- AstraZeneca, Innovative Medicines and Early Development Biotech Unit, Oncology Bioscience, Alderley Park, Macclesfield, Cheshire, United Kingdom
- AstraZeneca, Innovative Medicines and Early Development Biotech Unit, Oncology Bioscience, Little Chesterford, Cambridge, United Kingdom
- * E-mail: (TAW); (STD)
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34
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Roles for the Rad27 Flap Endonuclease in Mitochondrial Mutagenesis and Double-Strand Break Repair in Saccharomyces cerevisiae. Genetics 2017; 206:843-857. [PMID: 28450457 DOI: 10.1534/genetics.116.195149] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 04/18/2017] [Indexed: 01/07/2023] Open
Abstract
The structure-specific nuclease, Rad27p/FEN1, plays a crucial role in DNA repair and replication mechanisms in the nucleus. Genetic assays using the rad27-∆ mutant have shown altered rates of DNA recombination, microsatellite instability, and point mutation in mitochondria. In this study, we examined the role of Rad27p in mitochondrial mutagenesis and double-strand break (DSB) repair in Saccharomyces cerevisiae Our findings show that Rad27p is essential for efficient mitochondrial DSB repair by a pathway that generates deletions at a region flanked by direct repeat sequences. Mutant analysis suggests that both exonuclease and endonuclease activities of Rad27p are required for its role in mitochondrial DSB repair. In addition, we found that the nuclease activities of Rad27p are required for the prevention of mitochondrial DNA (mtDNA) point mutations, and in the generation of spontaneous mtDNA rearrangements. Overall, our findings underscore the importance of Rad27p in the maintenance of mtDNA, and demonstrate that it participates in multiple DNA repair pathways in mitochondria, unlinked to nuclear phenotypes.
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35
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Kathera C, Zhang J, Janardhan A, Sun H, Ali W, Zhou X, He L, Guo Z. Interacting partners of FEN1 and its role in the development of anticancer therapeutics. Oncotarget 2017; 8:27593-27602. [PMID: 28187440 PMCID: PMC5432360 DOI: 10.18632/oncotarget.15176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 01/24/2017] [Indexed: 11/25/2022] Open
Abstract
Protein-protein interaction (PPI) plays a key role in cellular communication, Protein-protein interaction connected with each other with hubs and nods involved in signaling pathways. These interactions used to develop network based biomarkers for early diagnosis of cancer. FEN1(Flap endonuclease 1) is a central component in cellular metabolism, over expression and decrease of FEN1 levels may cause cancer, these regulation changes of Flap endonuclease 1reported in many cancer cells, to consider this data may needs to develop a network based biomarker. The current review focused on types of PPI, based on nature, detection methods and its role in cancer. Interacting partners of Flap endonuclease 1 role in DNA replication repair and development of anticancer therapeutics based on Protein-protein interaction data.
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Affiliation(s)
- Chandrasekhar Kathera
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Jing Zhang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Avilala Janardhan
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Hongfang Sun
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Wajid Ali
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Xiaolong Zhou
- The Laboratory of Animal Genetics, Breeding, and Reproduction, College of Animal Science and Technology, Zhejiang Agriculture and Forestry University, Hangzhou, China
| | - Lingfeng He
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Zhigang Guo
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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36
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Dehé PM, Gaillard PHL. Control of structure-specific endonucleases to maintain genome stability. Nat Rev Mol Cell Biol 2017; 18:315-330. [PMID: 28327556 DOI: 10.1038/nrm.2016.177] [Citation(s) in RCA: 116] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Structure-specific endonucleases (SSEs) have key roles in DNA replication, recombination and repair, and emerging roles in transcription. These enzymes have specificity for DNA secondary structure rather than for sequence, and therefore their activity must be precisely controlled to ensure genome stability. In this Review, we discuss how SSEs are controlled as part of genome maintenance pathways in eukaryotes, with an emphasis on the elaborate mechanisms that regulate the members of the major SSE families - including the xeroderma pigmentosum group F-complementing protein (XPF) and MMS and UV-sensitive protein 81 (MUS81)-dependent nucleases, and the flap endonuclease 1 (FEN1), XPG and XPG-like endonuclease 1 (GEN1) enzymes - during processes such as DNA adduct repair, Holliday junction processing and replication stress. We also discuss newly characterized connections between SSEs and other classes of DNA-remodelling enzymes and cell cycle control machineries, which reveal the importance of SSE scaffolds such as the synthetic lethal of unknown function 4 (SLX4) tumour suppressor for the maintenance of genome stability.
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Affiliation(s)
- Pierre-Marie Dehé
- Centre de Recherche en Cancérologie de Marseille, CRCM, CNRS, Aix Marseille Université, INSERM, Institut Paoli-Calmettes, 27 Boulevard Leï Roure, 13009 Marseille, France
| | - Pierre-Henri L Gaillard
- Centre de Recherche en Cancérologie de Marseille, CRCM, CNRS, Aix Marseille Université, INSERM, Institut Paoli-Calmettes, 27 Boulevard Leï Roure, 13009 Marseille, France
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37
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Sang Y, Bo L, Gu H, Yang W, Chen Y. Flap endonuclease-1 rs174538 G>A polymorphisms are associated with the risk of esophageal cancer in a Chinese population. Thorac Cancer 2017; 8:192-196. [PMID: 28319330 PMCID: PMC5415465 DOI: 10.1111/1759-7714.12422] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 01/01/2017] [Accepted: 01/07/2017] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Esophageal cancer has a high mortality rate, particularly in Asia, and there are obvious racial differences in regard to incidence. The purpose of our study was to assess the genetic susceptibility of functional single nucleotide polymorphisms in flap endonuclease-1 (FEN1) in esophageal squamous cell carcinoma ESCC. METHODS Clinical blood samples of 629 ESCC cases and 686 control samples were collected. The ligation detection reaction method was used to determine FEN 1 rs174538 G>A genotypes. RESULTS A significantly decreased risk of ESCC was associated with FEN1 rs174538 GA genotypes among patients under 63 years old. CONCLUSIONS Our results suggest that functional polymorphism FEN1 rs174538 G>A might affect personal susceptibility to ESCC. This result provides a solid theoretical foundation for further clinical study using larger sample sizes.
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Affiliation(s)
- Yonghua Sang
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Lin Bo
- Department of Rheumatology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Haiyong Gu
- Department of Cardiothoracic Surgery, Shanghai Chest Hospital, Shanghai, China.,Department of Cardiothoracic Surgery, Affiliated People's Hospital of Jiangsu University, Zhenjiang, China
| | - Wengtao Yang
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Yongbing Chen
- Department of Cardiothoracic Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, China
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38
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Zhou L, Dai H, Wu J, Zhou M, Yuan H, Du J, Yang L, Wu X, Xu H, Hua Y, Xu J, Zheng L, Shen B. Role of FEN1 S187 phosphorylation in counteracting oxygen-induced stress and regulating postnatal heart development. FASEB J 2016; 31:132-147. [PMID: 27694478 DOI: 10.1096/fj.201600631r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 09/16/2016] [Indexed: 12/22/2022]
Abstract
Flap endonuclease 1 (FEN1) phosphorylation is proposed to regulate the action of FEN1 in DNA repair as well as Okazaki fragment maturation. However, the biologic significance of FEN1 phosphorylation in response to DNA damage remains unknown. Here, we report an in vivo role for FEN1 phosphorylation, using a mouse line carrying S187A FEN1, which abolishes FEN1 phosphorylation. Although S187A mouse embryonic fibroblast cells showed normal proliferation under low oxygen levels (2%), the mutant cells accumulated oxidative DNA damage, activated DNA damage checkpoints, and showed G1-phase arrest at atmospheric oxygen levels (21%). This suggests an essential role for FEN1 phosphorylation in repairing oxygen-induced DNA damage and maintaining proper cell cycle progression. Consistently, the mutant cardiomyocytes showed G1-phase arrest due to activation of the p53-mediated DNA damage response at the neonatal stage, which reduces the proliferation potential of the cardiomyocytes and impairs heart development. Nearly 50% of newborns with the S187A mutant died in the first week due to failure to undergo the peroxisome proliferator-activated receptor signaling-dependent switch from glycolysis to fatty acid oxidation. The adult mutant mice developed dilated hearts and showed significantly shorter life spans. Altogether, our results reveal an important role of FEN1 phosphorylation to counteract oxygen-induced stress in the heart during the fetal-to-neonatal transition.-Zhou, L., Dai, H., Wu, J., Zhou, M., Yuan, H., Du, J., Yang, L., Wu, X., Xu, H., Hua, Y., Xu, J., Zheng, L., Shen, B. Role of FEN1 S187 phosphorylation in counteracting oxygen-induced stress and regulating postnatal heart development.
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Affiliation(s)
- Lina Zhou
- College of Life Sciences and Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China.,Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Huifang Dai
- Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Jian Wu
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, California, USA
| | - Mian Zhou
- Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Hua Yuan
- Department of Diagnostic Ultrasound, Shaoxing Women and Children's Hospital, Shaoxing, China
| | - Juan Du
- Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA
| | - Lu Yang
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California, USA; and
| | - Xiwei Wu
- Department of Molecular and Cellular Biology, Beckman Research Institute of City of Hope, Duarte, California, USA; and
| | - Hong Xu
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Yuejin Hua
- Key Laboratory of Chinese Ministry of Agriculture for Nuclear-Agricultural Sciences, Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Jian Xu
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, California, USA
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA;
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics and Beckman Research Institute of City of Hope, Duarte, California, USA;
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39
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Zhang J, Xie S, Zhu JK, Gong Z. Requirement for flap endonuclease 1 (FEN1) to maintain genomic stability and transcriptional gene silencing in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:629-40. [PMID: 27231839 PMCID: PMC5508578 DOI: 10.1111/tpj.13224] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/17/2016] [Accepted: 05/25/2016] [Indexed: 05/02/2023]
Abstract
As a central component in the maturation of Okazaki fragments, flap endonuclease 1 (FEN1) removes the 5'-flap and maintains genomic stability. Here, FEN1 was cloned as a suppressor of transcriptional gene silencing (TGS) from a forward genetic screen. FEN1 is abundant in the root and shoot apical meristems and FEN1-GFP shows a nucleolus-localized signal in tobacco cells. The Arabidopsis fen1-1 mutant is hypersensitive to methyl methanesulfonate and shows reduced telomere length. Interestingly, genome-wide chromatin immunoprecipitation and RNA sequencing results demonstrate that FEN1 mutation leads to a decrease in the level of H3K27me3 and an increase in the expression of a subset of genes marked with H3K27me3. Overall, these results uncover a role for FEN1 in mediating TGS as well as maintaining genome stability in Arabidopsis.
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Affiliation(s)
- Jixiang Zhang
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Shaojun Xie
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47906, USA
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, IN, 47906, USA
| | - Zhizhong Gong
- State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
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40
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Rezaei M, Hashemi M, Sanaei S, Mashhadi MA, Hashemi SM, Bahari G, Taheri M. FEN1 -69G>A and +4150G>T polymorphisms and breast cancer risk. Biomed Rep 2016; 5:455-460. [PMID: 27699013 DOI: 10.3892/br.2016.738] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2016] [Accepted: 06/30/2016] [Indexed: 01/08/2023] Open
Abstract
Flap endonuclease 1 (FEN1), a DNA repair protein, is important in preventing carcinogenesis. Two functional germ line variants -69G>A (rs174538) and +4150G>T (rs4246215) in the FEN1 gene have been associated with risk of various types of cancer. The aim of the present study was to evaluate the possible impact of FEN1 polymorphisms on risk of breast cancer (BC) in a sample of Iranian subjects. The FEN1 -69G>A and +4150G>T polymorphisms were analyzed in a case-control study that included 266 BC patients and 225 healthy females. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to genotype the variants. The findings demonstrated that the FEN1 -69G>A and +4150G>T polymorphisms were not associated with BC risk in co-dominant, dominant and recessive inheritance models. The findings indicated that GG/GT, GA/GG and GA/TT genotypes significantly decreased the risk of BC when compared with -69GG/+4150GG. Furthermore, haplotype analysis indicated that -69G/+4150T as well as -69A/+4150G significantly decreased the risk of BC compared with -69G/+4150G. Thus, these findings demonstrated that haplotypes of FEN1 -69G>A and +4150G>T polymorphisms decreased the risk of BC in an Iranian population. Further studies with larger sample sizes and different ethnicities are required to validate the present findings.
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Affiliation(s)
- Maryam Rezaei
- Cellular and Molecular Research Center, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran; Department of Clinical Biochemistry, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Mohammad Hashemi
- Cellular and Molecular Research Center, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran; Department of Clinical Biochemistry, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Sara Sanaei
- Department of Clinical Biochemistry, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Mohammad Ali Mashhadi
- Department of Internal Medicine, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Seyed Mehdi Hashemi
- Department of Internal Medicine, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Gholamreza Bahari
- Department of Clinical Biochemistry, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
| | - Mohsen Taheri
- Department of Genetics, School of Medicine, Zahedan University of Medical Sciences, Zahedan 98167-43181, Iran
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The FEN1 L209P mutation interferes with long-patch base excision repair and induces cellular transformation. Oncogene 2016; 36:194-207. [PMID: 27270424 PMCID: PMC5140775 DOI: 10.1038/onc.2016.188] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2015] [Revised: 04/12/2016] [Accepted: 04/12/2016] [Indexed: 12/20/2022]
Abstract
Flap endonuclease-1 (FEN1) is a multifunctional, structure-specific nuclease that has a critical role in maintaining human genome stability. FEN1 mutations have been detected in human cancer specimens and have been suggested to cause genomic instability and cancer predisposition. However, the exact relationship between FEN1 deficiency and cancer susceptibility remains unclear. In the current work, we report a novel colorectal cancer-associated FEN1 mutation, L209P. This mutant protein lacks the FEN, exonuclease (EXO) and gap endonuclease (GEN) activities of FEN1 but retains DNA-binding affinity. The L209P FEN1 variant interferes with the function of the wild-type FEN1 enzyme in a dominant-negative manner and impairs long-patch base excision repair in vitro and in vivo. Expression of L209P FEN1 sensitizes cells to DNA damage, resulting in endogenous genomic instability and cellular transformation, as well as tumor growth in a mouse xenograft model. These data indicate that human cancer-associated genetic alterations in the FEN1 gene can contribute substantially to cancer development.
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Direct observation of DNA threading in flap endonuclease complexes. Nat Struct Mol Biol 2016; 23:640-6. [PMID: 27273516 PMCID: PMC4939078 DOI: 10.1038/nsmb.3241] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 05/10/2016] [Indexed: 02/06/2023]
Abstract
Maintenance of genome integrity requires that branched nucleic acid
molecules are accurately processed to produce double-helical DNA. Flap
endonucleases are essential enzymes that trim such branched molecules generated
by Okazaki fragment synthesis during replication. Here, we report crystal
structures of bacteriophage T5 flap endonuclease in complexes with intact DNA
substrates, and products, at resolutions of 1.9–2.2 Å. They reveal
single-stranded DNA threading through a hole in the enzyme enclosed by an
inverted V-shaped helical arch straddling the active site. Residues lining the
hole induce an unusual barb-like conformation in the DNA substrate juxtaposing
the scissile phosphate and essential catalytic metal ions. A series of complexes
and biochemical analyses show how the substrate’s single-stranded branch
approaches, threads through, and finally emerges on the far side of the enzyme.
Our studies suggest that substrate recognition involves an unusual
“fly-casting, thread, bend and barb” mechanism.
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Samadder P, Aithal R, Belan O, Krejci L. Cancer TARGETases: DSB repair as a pharmacological target. Pharmacol Ther 2016; 161:111-131. [PMID: 26899499 DOI: 10.1016/j.pharmthera.2016.02.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Cancer is a disease attributed to the accumulation of DNA damages due to incapacitation of DNA repair pathways resulting in genomic instability and a mutator phenotype. Among the DNA lesions, double stranded breaks (DSBs) are the most toxic forms of DNA damage which may arise as a result of extrinsic DNA damaging agents or intrinsic replication stress in fast proliferating cancer cells. Accurate repair of DSBs is therefore paramount to the cell survival, and several classes of proteins such as kinases, nucleases, helicases or core recombinational proteins have pre-defined jobs in precise execution of DSB repair pathways. On one hand, the proper functioning of these proteins ensures maintenance of genomic stability in normal cells, and on the other hand results in resistance to various drugs employed in cancer therapy and therefore presents a suitable opportunity for therapeutic targeting. Higher relapse and resistance in cancer patients due to non-specific, cytotoxic therapies is an alarming situation and it is becoming more evident to employ personalized treatment based on the genetic landscape of the cancer cells. For the success of personalized treatment, it is of immense importance to identify more suitable targetable proteins in DSB repair pathways and also to explore new synthetic lethal interactions with these pathways. Here we review the various alternative approaches to target the various protein classes termed as cancer TARGETases in DSB repair pathway to obtain more beneficial and selective therapy.
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Affiliation(s)
- Pounami Samadder
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital in Brno, 60200 Brno, Czech Republic
| | - Rakesh Aithal
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; Department of Biology, Masaryk University, 62500 Brno, Czech Republic
| | - Ondrej Belan
- Department of Biology, Masaryk University, 62500 Brno, Czech Republic
| | - Lumir Krejci
- National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital in Brno, 60200 Brno, Czech Republic; Department of Biology, Masaryk University, 62500 Brno, Czech Republic.
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Cheng IC, Chen BC, Shuai HH, Chien FC, Chen P, Hsieh TS. Wuho Is a New Member in Maintaining Genome Stability through its Interaction with Flap Endonuclease 1. PLoS Biol 2016; 14:e1002349. [PMID: 26751069 PMCID: PMC4709127 DOI: 10.1371/journal.pbio.1002349] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 12/04/2015] [Indexed: 11/18/2022] Open
Abstract
Replication forks are vulnerable to wayward nuclease activities. We report here our discovery of a new member in guarding genome stability at replication forks. We previously isolated a Drosophila mutation, wuho (wh, no progeny), characterized by a severe fertility defect and affecting expression of a protein (WH) in a family of conserved proteins with multiple WD40 repeats. Knockdown of WH by siRNA in Drosophila, mouse, and human cultured cells results in DNA damage with strand breaks and apoptosis through ATM/Chk2/p53 signaling pathway. Mice with mWh knockout are early embryonic lethal and display DNA damage. We identify that the flap endonuclease 1 (FEN1) is one of the interacting proteins. Fluorescence microscopy showed the localization of WH at the site of nascent DNA synthesis along with other replication proteins, including FEN1 and PCNA. We show that WH is able to modulate FEN1's endonucleolytic activities depending on the substrate DNA structure. The stimulatory or inhibitory effects of WH on FEN1's flap versus gap endonuclease activities are consistent with the proposed WH's functions in protecting the integrity of replication fork. These results suggest that wh is a new member of the guardians of genome stability because it regulates FEN1's potential DNA cleavage threat near the site of replication.
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Affiliation(s)
- I-Cheng Cheng
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Betty Chamay Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Hung-Hsun Shuai
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Fan-Ching Chien
- Department of Optics and Photonics, National Central University, Chung-Li, Taiwan
| | - Peilin Chen
- Research Center for Applied Sciences, Academia Sinica, Taipei, Taiwan
| | - Tao-shih Hsieh
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.,Department of Biochemistry, Duke University, Durham, North Carolina, United States of America
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Zhang Y, Wen C, Liu S, Zheng L, Shen B, Tao Y. Shade avoidance 6 encodes an Arabidopsis flap endonuclease required for maintenance of genome integrity and development. Nucleic Acids Res 2015; 44:1271-84. [PMID: 26721386 PMCID: PMC4756833 DOI: 10.1093/nar/gkv1474] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 12/03/2015] [Indexed: 12/01/2022] Open
Abstract
Flap endonuclease-1 (FEN1) belongs to the Rad2 family of structure-specific nucleases. It is required for several DNA metabolic pathways, including DNA replication and DNA damage repair. Here, we have identified a shade avoidance mutant, sav6, which reduces the mRNA splicing efficiency of SAV6. We have demonstrated that SAV6 is an FEN1 homologue that shows double-flap endonuclease and gap-dependent endonuclease activity, but lacks exonuclease activity. sav6 mutants are hypersensitive to DNA damage induced by ultraviolet (UV)-C radiation and reagents that induce double-stranded DNA breaks, but exhibit normal responses to chemicals that block DNA replication. Signalling components that respond to DNA damage are constitutively activated in sav6 mutants. These data indicate that SAV6 is required for DNA damage repair and the maintenance of genome integrity. Mutant sav6 plants also show reduced root apical meristem (RAM) size and defective quiescent centre (QC) development. The expression of SMR7, a cell cycle regulatory gene, and ERF115 and PSK5, regulators of QC division, is increased in sav6 mutants. Their constitutive induction is likely due to the elevated DNA damage responses in sav6 and may lead to defects in the development of the RAM and QC. Therefore, SAV6 assures proper root development through maintenance of genome integrity.
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Affiliation(s)
- Yijuan Zhang
- School of Life Sciences, Xiamen Plant Genetics Key Laboratory, Xiamen University, Xiamen 361102, China State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen 361102, China
| | - Chunhong Wen
- School of Life Sciences, Xiamen Plant Genetics Key Laboratory, Xiamen University, Xiamen 361102, China
| | - Songbai Liu
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA College of Life Sciences, Zhejiang University, Hangzhou, China Suzhou Health College, Suzhou Key Laboratory of Biotechnology for Laboratory Medicine, Suzhou, 215009, Jiangsu Province, China
| | - Li Zheng
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
| | - Binghui Shen
- Department of Cancer Genetics and Epigenetics, Beckman Research Institute of City of Hope, Duarte, CA 91010, USA
| | - Yi Tao
- School of Life Sciences, Xiamen Plant Genetics Key Laboratory, Xiamen University, Xiamen 361102, China State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen 361102, China
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YING N, WANG S, XU H, WANG Y. Association between FEN1 Polymorphisms -69G>A and 4150G>T with Susceptibility in Human Disease: A Meta-Analysis. IRANIAN JOURNAL OF PUBLIC HEALTH 2015; 44:1574-9. [PMID: 26811808 PMCID: PMC4724730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND As a DNA repair protein, flap endonuclease 1 is a key enzyme in maintaining genomic instability and preventing carcinogenesis. Two single nucleotide polymorphisms (SNPs), -69G>A and 4150G>T are associated with DNA damage. This meta-analysis is to evaluate the genetic effects of FEN1 gene SNPs (-69G/A and 4150G/T) and the susceptibility to diseases, including glioma risk, breast cancer, lung cancer, keratoconus (KC) and fuchs' endothelial corneal dystrophy (FECD). METHODS A literature search of PubMed and Embase was conducted to identify all eligible published studies. Five case-control studies were included with a total of 5612 cases and 6703 controls in this meta-analysis. Crude odds ratios (ORs) with their corresponding confidence intervals (95%CI) were used to assess the strength of the association. RESULTS The FEN1 -69G/A and 4150G/T polymorphisms were significantly associated with the disease risk. Our meta-analysis showed the FEN1 -69GG genotype was correlated to increase risk for the contained diseases compared with the -69AG genotype (OR=0.77, 95%CI=0.71∼0.83). Moreover, the FEN1 4150GG genotype could increase diseases risk compared with the 4150TG genotype (OR=0.81, 95%CI=0.75∼0.87). CONCLUSION The variant genotypes of the FEN1 -69G/A and FEN1 4150G/T polymorphisms may be associated with diseases susceptibility. However, more studies are needed to detect the disease risk in different ethnic populations.
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Affiliation(s)
- Nanjiao YING
- Inst. of Biomedical Engineering, Hangzhou Dianzi University, Hangzhou, China,Inst. of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China
| | - Shuo WANG
- Inst. of Biomedical Engineering, Hangzhou Dianzi University, Hangzhou, China
| | - Hong XU
- Inst. of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou, China,Corresponding Author:
| | - Yanyi WANG
- Inst. of Biomedical Engineering, Hangzhou Dianzi University, Hangzhou, China
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Abstract
RecQ helicases are a family of highly conserved proteins that maintain genomic stability through their important roles in replication restart mechanisms. Cellular phenotypes of RECQ1 deficiency are indicative of aberrant repair of stalled replication forks, but the molecular functions of RECQ1, the most abundant of the five known human RecQ homologues, have remained poorly understood. We show that RECQ1 associates with FEN-1 (flap endonuclease-1) in nuclear extracts and exhibits direct protein interaction in vitro. Recombinant RECQ1 significantly stimulated FEN-1 endonucleolytic cleavage of 5'-flap DNA substrates containing non-telomeric or telomeric repeat sequence. RECQ1 and FEN-1 were constitutively present at telomeres and their binding to the telomeric chromatin was enhanced following DNA damage. Telomere residence of FEN-1 was dependent on RECQ1 since depletion of RECQ1 reduced FEN-1 binding to telomeres in unperturbed cycling cells. Our results confirm a conserved collaboration of human RecQ helicases with FEN-1 and suggest both overlapping and specialized roles of RECQ1 in the processing of DNA structure intermediates proposed to arise during replication, repair and recombination.
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48
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Ren H, Ma H, Ke Y, Ma X, Xu D, Lin S, Wang X, Dai ZJ. Flap endonuclease 1 polymorphisms (rs174538 and rs4246215) contribute to an increased cancer risk: Evidence from a meta-analysis. Mol Clin Oncol 2015; 3:1347-1352. [PMID: 26807246 DOI: 10.3892/mco.2015.617] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 02/26/2015] [Indexed: 11/05/2022] Open
Abstract
Flap endonuclease-1 (FEN1) is a key factor during the maintenance of genomic stability and protection against tumorigenesis. Since the identification of functional polymorphisms of FEN1 (rs174538 and rs4246215), numerous studies have evaluated the association between the two single-nucleotide polymorphisms and cancer risk. To derive a more precise estimation, a meta-analysis was performed on the association between the FEN1 polymorphisms (rs174538 and rs4246215) and cancer risk. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the strength of the associations. Thirteen case-control studies, including 5,108 cases and 6,382 case-free controls, were identified. For rs174538, individuals with the GG or GA genotype had an increased risk of cancer when compared to the -69AA genotype (AA vs. GG: OR, 1.85; 95% CI, 1.65-2.08; P<0.00001; AA vs. GA: OR, 1.43; 95% CI, 1.27-1.60; P<0.00001; AA vs. GG+GA: OR, 1.28; 95% CI, 1.16-1.42; P<0.00001). For rs4246215, similar results were identified, as the GG or GT genotype was significantly associated with the increased cancer risk when compared to TT (TT vs. GG: OR, 1.71; 95% CI, 1.52-1.92; P<0.00001; TT vs. GT: OR, 1.34; 95% CI, 1.20-1.50; P<0.00001; TT vs. GG+GT: OR, 1.50; 95% CI, 1.35-1.67; P<0.00001). The present meta-analysis indicated that FEN1 rs174538 and rs4246215 polymorphisms may contribute to an increased risk of cancer.
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Affiliation(s)
- Hongtao Ren
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Hongbing Ma
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Yue Ke
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Xiaobin Ma
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Dan Xu
- Center for Translational Medicine, Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710028, P.R. China
| | - Shuai Lin
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Xijing Wang
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China
| | - Zhi-Jun Dai
- Department of Oncology, The Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China; Center for Translational Medicine, Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi 710028, P.R. China
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Xu Y, Her C. Inhibition of Topoisomerase (DNA) I (TOP1): DNA Damage Repair and Anticancer Therapy. Biomolecules 2015; 5:1652-70. [PMID: 26287259 PMCID: PMC4598769 DOI: 10.3390/biom5031652] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 07/14/2015] [Indexed: 12/31/2022] Open
Abstract
Most chemotherapy regimens contain at least one DNA-damaging agent that preferentially affects the growth of cancer cells. This strategy takes advantage of the differences in cell proliferation between normal and cancer cells. Chemotherapeutic drugs are usually designed to target rapid-dividing cells because sustained proliferation is a common feature of cancer [1,2]. Rapid DNA replication is essential for highly proliferative cells, thus blocking of DNA replication will create numerous mutations and/or chromosome rearrangements—ultimately triggering cell death [3]. Along these lines, DNA topoisomerase inhibitors are of great interest because they help to maintain strand breaks generated by topoisomerases during replication. In this article, we discuss the characteristics of topoisomerase (DNA) I (TOP1) and its inhibitors, as well as the underlying DNA repair pathways and the use of TOP1 inhibitors in cancer therapy.
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Affiliation(s)
- Yang Xu
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Mail Drop 64-7520, Pullman, WA 99164, USA.
| | - Chengtao Her
- School of Molecular Biosciences, College of Veterinary Medicine, Washington State University, Mail Drop 64-7520, Pullman, WA 99164, USA.
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50
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Martínez P, Blasco MA. Replicating through telomeres: a means to an end. Trends Biochem Sci 2015; 40:504-15. [PMID: 26188776 DOI: 10.1016/j.tibs.2015.06.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/08/2015] [Accepted: 06/12/2015] [Indexed: 02/07/2023]
Abstract
Proper replication of the telomeric DNA at chromosome ends is critical for preserving genome integrity. Yet, telomeres present challenges for the replication machinery, such as their repetitive and heterochromatic nature and their potential to form non-Watson-Crick structures as well as the fact that they are transcribed. Numerous telomere-bound proteins are required to facilitate progression of the replication fork throughout telomeric DNA. In particular, shelterin plays crucial functions in telomere length regulation, protection of telomeres from nuclease degradation, control of DNA damage response at telomeres, and the recruitment of associated factors required for telomere DNA processing and replication. In this review we discuss the recently uncovered functions of mammalian telomere-specific and telomere-associated proteins that facilitate proper telomere replication.
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Affiliation(s)
- Paula Martínez
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Madrid E-28029, Spain
| | - Maria A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Research Centre (CNIO), Madrid E-28029, Spain.
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