1
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Kyriukha Y, Watkins MB, Redington JM, Dastvan R, Uversky VN, Hopkins JB, Pozzi N, Korolev S. The strand exchange domain of tumor suppressor PALB2 is intrinsically disordered and promotes oligomerization-dependent DNA compaction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.01.543259. [PMID: 37333393 PMCID: PMC10274692 DOI: 10.1101/2023.06.01.543259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
The Partner and Localizer of BRCA2 (PALB2) is a scaffold protein that links BRCA1 with BRCA2 to initiate homologous recombination (HR). PALB2 interaction with DNA strongly enhances HR efficiency in cells. The PALB2 DNA-binding domain (PALB2-DBD) supports strand exchange, a complex multistep reaction conducted by only a few proteins such as RecA-like recombinases and Rad52. Using bioinformatics analysis, small-angle X-ray scattering, circular dichroism, and electron paramagnetic spectroscopy, we determined that PALB2-DBD is an intrinsically disordered region (IDR) forming compact molten globule-like dimer. IDRs contribute to oligomerization synergistically with the coiled-coil interaction. Using confocal single-molecule FRET we demonstrated that PALB2-DBD compacts single-stranded DNA even in the absence of DNA secondary structures. The compaction is bimodal, oligomerization-dependent, and is driven by IDRs, suggesting a novel strand exchange mechanism. Intrinsically disordered proteins (IDPs) are prevalent in the human proteome. Novel DNA binding properties of PALB2-DBD and the complexity of strand exchange mechanism significantly expands the functional repertoire of IDPs. Multivalent interactions and bioinformatics analysis suggest that PALB2 function is likely to depend on formation of protein-nucleic acids condensates. Similar intrinsically disordered DBDs may use chaperone-like mechanism to aid formation and resolution of DNA and RNA multichain intermediates during DNA replication, repair and recombination.
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Affiliation(s)
- Yevhenii Kyriukha
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Maxwell B Watkins
- The Biophysics Collaborative Access Team (BioCat), Departments of Biology and Physics, Illinois Institute of Technology, Chicago, IL
| | - Jennifer M Redington
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Reza Dastvan
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Jesse B Hopkins
- The Biophysics Collaborative Access Team (BioCat), Departments of Biology and Physics, Illinois Institute of Technology, Chicago, IL
| | - Nicola Pozzi
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Sergey Korolev
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
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2
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Ito M, Fujita Y, Shinohara A. Positive and negative regulators of RAD51/DMC1 in homologous recombination and DNA replication. DNA Repair (Amst) 2024; 134:103613. [PMID: 38142595 DOI: 10.1016/j.dnarep.2023.103613] [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: 08/02/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 12/26/2023]
Abstract
RAD51 recombinase plays a central role in homologous recombination (HR) by forming a nucleoprotein filament on single-stranded DNA (ssDNA) to catalyze homology search and strand exchange between the ssDNA and a homologous double-stranded DNA (dsDNA). The catalytic activity of RAD51 assembled on ssDNA is critical for the DNA-homology-mediated repair of DNA double-strand breaks in somatic and meiotic cells and restarting stalled replication forks during DNA replication. The RAD51-ssDNA complex also plays a structural role in protecting the regressed/reversed replication fork. Two types of regulators control RAD51 filament formation, stability, and dynamics, namely positive regulators, including mediators, and negative regulators, so-called remodelers. The appropriate balance of action by the two regulators assures genome stability. This review describes the roles of positive and negative RAD51 regulators in HR and DNA replication and its meiosis-specific homolog DMC1 in meiotic recombination. We also provide future study directions for a comprehensive understanding of RAD51/DMC1-mediated regulation in maintaining and inheriting genome integrity.
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Affiliation(s)
- Masaru Ito
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Yurika Fujita
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
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3
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Itriago H, Marufee Islam Z, Cohn M. Characterization of the RAD52 Gene in the Budding Yeast Naumovozyma castellii. Genes (Basel) 2023; 14:1908. [PMID: 37895257 PMCID: PMC10606518 DOI: 10.3390/genes14101908] [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: 09/14/2023] [Revised: 09/29/2023] [Accepted: 09/30/2023] [Indexed: 10/29/2023] Open
Abstract
Several sources of DNA damage compromise the integrity and stability of the genome of every organism. Specifically, DNA double-strand breaks (DSBs) can have lethal consequences for the cell. To repair this type of DNA damage, the cells employ homology-directed repair pathways or non-homologous end joining. Homology-directed repair requires the activity of the RAD52 epistasis group of genes. Rad52 is the main recombination protein in the budding yeast Saccharomyces cerevisiae, and rad52Δ mutants have been characterized to show severe defects in DSB repair and other recombination events. Here, we identified the RAD52 gene in the budding yeast Naumovozyma castellii. Our analysis showed that the primary amino acid sequence of N. castellii Rad52 shared 70% similarity with S. cerevisiae Rad52. To characterize the gene function, we developed rad52Δ mutant strains by targeted gene replacement transformation. We found that N. castellii rad52Δ mutants showed lowered growth capacity, a moderately altered cell morphology and increased sensitivity to genotoxic agents. The decreased viability of the N. castellii rad52Δ mutants in the presence of genotoxic agents indicates that the role of the Rad52 protein in the repair of DNA damage is conserved in this species.
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Affiliation(s)
| | | | - Marita Cohn
- Department of Biology, Genetics Group, Lund University, Sölvegatan 35, SE-223 62 Lund, Sweden
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4
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Kyriukha Y, Watkins MB, Redington JM, Dastvan R, Uversky VN, Hopkins J, Pozzi N, Korolev S. The PALB2 DNA-binding domain is an intrinsically disordered recombinase. RESEARCH SQUARE 2023:rs.3.rs-3235465. [PMID: 37790553 PMCID: PMC10543426 DOI: 10.21203/rs.3.rs-3235465/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The Partner and Localizer of BRCA2 (PALB2) tumor suppressor is a scaffold protein that links BRCA1 with BRCA2 to initiate homologous recombination (HR). PALB2 interaction with DNA strongly enhances HR efficiency. The PALB2 DNA-binding domain (PALB2-DBD) supports DNA strand exchange, a complex multistep reaction supported by only a few protein families such as RecA-like recombinases or Rad52. The mechanisms of PALB2 DNA binding and strand exchange are unknown. We performed circular dichroism, electron paramagnetic spectroscopy, and small-angle X-ray scattering analyses and determined that PALB2-DBD is intrinsically disordered, even when bound to DNA. The intrinsically disordered nature of this domain was further supported by bioinformatics analysis. Intrinsically disordered proteins (IDPs) are prevalent in the human proteome and have many important biological functions. The complexity of the strand exchange reaction significantly expands the functional repertoire of IDPs. The results of confocal single-molecule FRET indicated that PALB2-DBD binding leads to oligomerization-dependent DNA compaction. We hypothesize that PALB2-DBD uses a chaperone-like mechanism to aid formation and resolution of complex DNA and RNA multichain intermediates during DNA replication and repair. Since PALB2-DBD alone or within the full-length PALB2 is predicted to have strong liquid-liquid phase separation (LLPS) potential, protein-nucleic acids condensates are likely to play a role in complex functionality of PALB2-DBD. Similar DNA-binding intrinsically disordered regions may represent a novel class of functional domains that evolved to function in eukaryotic nucleic acid metabolism complexes.
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Affiliation(s)
- Yevhenii Kyriukha
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | | | - Jennifer M Redington
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Reza Dastvan
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL
| | - Jesse Hopkins
- BioCat, Advanced Photon Source, Argonne National Lab, Argonne, IL
| | - Nicola Pozzi
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
| | - Sergey Korolev
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St Louis, MO
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5
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Richards F, Llorca-Cardenosa MJ, Langton J, Buch-Larsen SC, Shamkhi NF, Sharma AB, Nielsen ML, Lakin ND. Regulation of Rad52-dependent replication fork recovery through serine ADP-ribosylation of PolD3. Nat Commun 2023; 14:4310. [PMID: 37463936 DOI: 10.1038/s41467-023-40071-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 07/06/2023] [Indexed: 07/20/2023] Open
Abstract
Although Poly(ADP-ribose)-polymerases (PARPs) are key regulators of genome stability, how site-specific ADP-ribosylation regulates DNA repair is unclear. Here, we describe a novel role for PARP1 and PARP2 in regulating Rad52-dependent replication fork repair to maintain cell viability when homologous recombination is dysfunctional, suppress replication-associated DNA damage, and maintain genome stability. Mechanistically, Mre11 and ATM are required for induction of PARP activity in response to replication stress that in turn promotes break-induced replication (BIR) through assembly of Rad52 at stalled/damaged replication forks. Further, by mapping ADP-ribosylation sites induced upon replication stress, we identify that PolD3 is a target for PARP1/PARP2 and that its site-specific ADP-ribosylation is required for BIR activity, replication fork recovery and genome stability. Overall, these data identify a critical role for Mre11-dependent PARP activation and site-specific ADP-ribosylation in regulating BIR to maintain genome integrity during DNA synthesis.
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Affiliation(s)
- Frederick Richards
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | | | - Jamie Langton
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | - Sara C Buch-Larsen
- Novo Nordisk Foundation Centre for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Noor F Shamkhi
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK
| | | | - Michael L Nielsen
- Novo Nordisk Foundation Centre for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen, Denmark
| | - Nicholas D Lakin
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, UK.
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6
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Sharma AB, Erasimus H, Pinto L, Caron MC, Gopaul D, Peterlini T, Neumann K, Nazarov PV, Fritah S, Klink B, Herold-Mende CC, Niclou SP, Pasero P, Calsou P, Masson JY, Britton S, Van Dyck E. XAB2 promotes Ku eviction from single-ended DNA double-strand breaks independently of the ATM kinase. Nucleic Acids Res 2021; 49:9906-9925. [PMID: 34500463 PMCID: PMC8464071 DOI: 10.1093/nar/gkab785] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 08/16/2021] [Accepted: 09/01/2021] [Indexed: 12/18/2022] Open
Abstract
Replication-associated single-ended DNA double-strand breaks (seDSBs) are repaired predominantly through RAD51-mediated homologous recombination (HR). Removal of the non-homologous end-joining (NHEJ) factor Ku from resected seDSB ends is crucial for HR. The coordinated actions of MRE11-CtIP nuclease activities orchestrated by ATM define one pathway for Ku eviction. Here, we identify the pre-mRNA splicing protein XAB2 as a factor required for resistance to seDSBs induced by the chemotherapeutic alkylator temozolomide. Moreover, we show that XAB2 prevents Ku retention and abortive HR at seDSBs induced by temozolomide and camptothecin, via a pathway that operates in parallel to the ATM-CtIP-MRE11 axis. Although XAB2 depletion preserved RAD51 focus formation, the resulting RAD51-ssDNA associations were unproductive, leading to increased NHEJ engagement in S/G2 and genetic instability. Overexpression of RAD51 or RAD52 rescued the XAB2 defects and XAB2 loss was synthetically lethal with RAD52 inhibition, providing potential perspectives in cancer therapy.
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Affiliation(s)
- Abhishek Bharadwaj Sharma
- DNA Repair and Chemoresistance Group, Department of Oncology, Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg
| | - Hélène Erasimus
- DNA Repair and Chemoresistance Group, Department of Oncology, Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,Faculty of Science, Technology and Communication, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Lia Pinto
- DNA Repair and Chemoresistance Group, Department of Oncology, Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg.,Faculty of Science, Technology and Communication, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Marie-Christine Caron
- CHU de Québec Research Center, Oncology Division, Québec City, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Québec City, Canada
| | - Diyavarshini Gopaul
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe Labellisée Ligue Contre le Cancer, Montpellier, France
| | - Thibaut Peterlini
- CHU de Québec Research Center, Oncology Division, Québec City, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Québec City, Canada
| | - Katrin Neumann
- DNA Repair and Chemoresistance Group, Department of Oncology, Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg
| | - Petr V Nazarov
- Quantitative Biology Unit, Multiomics Data Science Group, LIH, Luxembourg
| | - Sabrina Fritah
- NorLux Neuro-Oncology Laboratory, Department of Oncology, LIH, Luxembourg
| | - Barbara Klink
- National Center of Genetics, Laboratoire National de Santé, Dudelange, Luxembourg.,Functional Tumour Genetics Group, Department of Oncology, LIH, Luxembourg
| | | | - Simone P Niclou
- NorLux Neuro-Oncology Laboratory, Department of Oncology, LIH, Luxembourg.,Department of Biomedicine, University of Bergen, Norway
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS et Université de Montpellier, Equipe Labellisée Ligue Contre le Cancer, Montpellier, France
| | - Patrick Calsou
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France, Equipe Labellisée Ligue Nationale Contre le Cancer 2018
| | - Jean-Yves Masson
- CHU de Québec Research Center, Oncology Division, Québec City, Canada.,Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University Cancer Research Center, Québec City, Canada
| | - Sébastien Britton
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France, Equipe Labellisée Ligue Nationale Contre le Cancer 2018
| | - Eric Van Dyck
- DNA Repair and Chemoresistance Group, Department of Oncology, Luxembourg Institute of Health (LIH), Luxembourg, Luxembourg
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7
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Bernardi A, Gobelli D, Serna J, Nawrocka P, March-Rosselló G, Orduña A, Kozlowski P, Simarro M, de la Fuente MA. Novel fluorescent-based reporter cell line engineered for monitoring homologous recombination events. PLoS One 2021; 16:e0237413. [PMID: 33930025 PMCID: PMC8087102 DOI: 10.1371/journal.pone.0237413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 04/13/2021] [Indexed: 12/19/2022] Open
Abstract
Homologous recombination (HR) faithfully restores DNA double-strand breaks. Defects in this HR repair pathway are associated with cancer predisposition. In genetic engineering, HR has been used extensively to study gene function and it represents an ideal method of gene therapy for single gene disorders. Here, we present a novel assay to measure HR in living cells. The HR substrate consisted of a non-fluorescent 3’ truncated form of the eGFP gene and was integrated into the AAVS1 locus, known as a safe harbor. The donor DNA template comprised a 5’ truncated eGFP copy and was delivered via AAV particles. HR mediated repair restored full-length eGFP coding sequence, resulting in eGFP+ cells. The utility of our assay in quantifying HR events was validated by exploring the impact of the overexpression of HR promoters and the siRNA-mediated silencing of genes known to play a role in DNA repair on the frequency of HR. We conclude that this novel assay represents a useful tool to further investigate the mechanisms that control HR and test continually emerging tools for HR-mediated genome editing.
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Affiliation(s)
- Alejandra Bernardi
- Institute of Biomedicine and Molecular Genetics (IBGM) of Valladolid, Valladolid, Spain
| | - Dino Gobelli
- Institute of Biomedicine and Molecular Genetics (IBGM) of Valladolid, Valladolid, Spain
| | - Julia Serna
- Institute of Biomedicine and Molecular Genetics (IBGM) of Valladolid, Valladolid, Spain
| | - Paulina Nawrocka
- Department of Molecular Genetics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | | | - Antonio Orduña
- Division of Microbiology, Hospital Clínico of Valladolid, Valladolid, Spain.,Microbiology Department, University of Valladolid, Valladolid, Spain
| | - Piotr Kozlowski
- Department of Molecular Genetics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
| | - María Simarro
- Institute of Biomedicine and Molecular Genetics (IBGM) of Valladolid, Valladolid, Spain.,Department of Nursing-"Grupo de Investigación en Cuidados de Enfermería" GICE, University of Valladolid, Valladolid, Spain
| | - Miguel A de la Fuente
- Institute of Biomedicine and Molecular Genetics (IBGM) of Valladolid, Valladolid, Spain.,Department of Cell Biology, Histology and Pharmacology, University of Valladolid, Valladolid, Spain
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8
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Yang Q, Li Y, Sun R, Li J. Identification of a RAD52 Inhibitor Inducing Synthetic Lethality in BRCA2-Deficient Cancer Cells. Front Pharmacol 2021; 12:637825. [PMID: 33995041 PMCID: PMC8118686 DOI: 10.3389/fphar.2021.637825] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/12/2021] [Indexed: 11/16/2022] Open
Abstract
The breast cancer susceptibility gene 1/2 (BRCA1/2) is frequently mutated in many malignant tumors, such as breast cancer and ovarian cancer. Studies have demonstrated that inhibition of RAD52 gene function in BRCA2-deficient cancer causes synthetic lethality, suggesting a potential application of RAD52 in cancer-targeted therapy. In this study, we have performed a virtual screening by targeting the self-association domain (residues 85-159) of RAD52 with a library of 66,608 compounds and found one compound, C791-0064, that specifically inhibited the proliferation of BRCA2-deficient cancer cells. Our biochemical and cell-based experimental data suggested that C791-0064 specifically bound to RAD52 and disrupted the single-strand annealing activity of RAD52. Taken together, C791-0064 is a promising leading compound worthy of further exploitation in the context of BRCA-deficient targeted cancer therapy.
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Affiliation(s)
- Qianye Yang
- Institute of Cancer Biology and Drug Discovery, Chengdu University, Chengdu, China
- Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China
| | - Yu Li
- West China School of Pharmacy, Sichuan University, Chengdu, China
| | - Rong Sun
- Basic medical research center, School of medicine, Nantong University, Nantong, China
| | - Jian Li
- Institute of Cancer Biology and Drug Discovery, Chengdu University, Chengdu, China
- Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu, China
- School of Medicine, Chengdu University, Chengdu, China
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9
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Onaka AT, Su J, Katahira Y, Tang C, Zafar F, Aoki K, Kagawa W, Niki H, Iwasaki H, Nakagawa T. DNA replication machinery prevents Rad52-dependent single-strand annealing that leads to gross chromosomal rearrangements at centromeres. Commun Biol 2020; 3:202. [PMID: 32355220 PMCID: PMC7193609 DOI: 10.1038/s42003-020-0934-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 04/09/2020] [Indexed: 12/27/2022] Open
Abstract
Homologous recombination between repetitive sequences can lead to gross chromosomal rearrangements (GCRs). At fission yeast centromeres, Rad51-dependent conservative recombination predominantly occurs between inverted repeats, thereby suppressing formation of isochromosomes whose arms are mirror images. However, it is unclear how GCRs occur in the absence of Rad51 and how GCRs are prevented at centromeres. Here, we show that homology-mediated GCRs occur through Rad52-dependent single-strand annealing (SSA). The rad52-R45K mutation, which impairs SSA activity of Rad52 protein, dramatically reduces isochromosome formation in rad51 deletion cells. A ring-like complex Msh2-Msh3 and a structure-specific endonuclease Mus81 function in the Rad52-dependent GCR pathway. Remarkably, mutations in replication fork components, including DNA polymerase α and Swi1/Tof1/Timeless, change the balance between Rad51-dependent recombination and Rad52-dependent SSA at centromeres, increasing Rad52-dependent SSA that forms isochromosomes. Our results uncover a role of DNA replication machinery in the recombination pathway choice that prevents Rad52-dependent GCRs at centromeres.
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Affiliation(s)
- Atsushi T Onaka
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Chitose Laboratory Corporation, 2-13-3 Nogawa-honcho, Miyamae-ku, Kawasaki, Kanagawa, 216-0041, Japan
| | - Jie Su
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Yasuhiro Katahira
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Department of Immunoregulation, Institute of Medical Science, Tokyo Medical University, 6-1-1 Shinjuku-ku, Tokyo, 160-8402, Japan
| | - Crystal Tang
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Faria Zafar
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Keita Aoki
- Microbial Physiology Laboratory, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Wataru Kagawa
- Department of Chemistry, Graduate School of Science and Engineering, Meisei University, 2-1-1 Hodokubo, Hino, Tokyo, 191-8506, Japan
| | - Hironori Niki
- Microbial Physiology Laboratory, Department of Gene Function and Phenomics, National Institute of Genetics, 1111 Yata, Mishima, Shizuoka, 411-8540, Japan
| | - Hiroshi Iwasaki
- School of Life Science and Technology, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan.,Institute of Innovative Research, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan
| | - Takuro Nakagawa
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.
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10
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Brosh RM, Trakselis MA. Fine-tuning of the replisome: Mcm10 regulates fork progression and regression. Cell Cycle 2019; 18:1047-1055. [PMID: 31014174 DOI: 10.1080/15384101.2019.1609833] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Several decades of research have identified Mcm10 hanging around the replisome making several critical contacts with a number of proteins but with no real disclosed function. Recently, the O'Donnell laboratory has been better able to map the interactions of Mcm10 with a larger Cdc45/GINS/MCM (CMG) unwinding complex placing it at the front of the replication fork. They have shown biochemically that Mcm10 has the impressive ability to strip off single-strand binding protein (RPA) and reanneal complementary DNA strands. This has major implications in controlling DNA unwinding speed as well as responding to various situations where fork reversal is needed. This work opens up a number of additional facets discussed here revolving around accessing the DNA junction for different molecular purposes within a crowded replisome. Abbreviations: alt-NHEJ: Alternative Nonhomologous End-Joining; CC: Coli-Coil motif; CMG: Cdc45/GINS/MCM2-7; CMGM: Cdc45/GINS/Mcm2-7/Mcm10; CPT: Camptothecin; CSB: Cockayne Syndrome Group B protein; CTD: C-Terminal Domain; DSB: Double-Strand Break; DSBR: Double-Strand Break Repair; dsDNA: Double-Stranded DNA; GINS: go-ichi-ni-san, Sld5-Psf1-Psf2-Psf3; HJ Dis: Holliday Junction dissolution; HJ Res: Holliday Junction resolution; HR: Homologous Recombination; ICL: Interstrand Cross-Link; ID: Internal Domain; MCM: Minichromosomal Maintenance; ND: Not Determined; NTD: N-Terminal Domain; PCNA: Proliferating Cell Nuclear Antigen; RPA: Replication Protein A; SA: Strand Annealing; SE: Strand Exchange; SEW: Steric Exclusion and Wrapping; ssDNA: Single-Stranded DNA; TCR: Transcription-Coupled Repair; TOP1: Topoisomerase.
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Affiliation(s)
- Robert M Brosh
- a Laboratory of Molecular Gerontology , National Institute on Aging, National Institutes of Health , Baltimore , MD USA
| | - Michael A Trakselis
- b Department of Chemistry and Biochemistry , Baylor University , Waco , TX , USA
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11
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Prado F. Homologous Recombination: To Fork and Beyond. Genes (Basel) 2018; 9:genes9120603. [PMID: 30518053 PMCID: PMC6316604 DOI: 10.3390/genes9120603] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 11/29/2018] [Accepted: 11/29/2018] [Indexed: 12/15/2022] Open
Abstract
Accurate completion of genome duplication is threatened by multiple factors that hamper the advance and stability of the replication forks. Cells need to tolerate many of these blocking lesions to timely complete DNA replication, postponing their repair for later. This process of lesion bypass during DNA damage tolerance can lead to the accumulation of single-strand DNA (ssDNA) fragments behind the fork, which have to be filled in before chromosome segregation. Homologous recombination plays essential roles both at and behind the fork, through fork protection/lesion bypass and post-replicative ssDNA filling processes, respectively. I review here our current knowledge about the recombination mechanisms that operate at and behind the fork in eukaryotes, and how these mechanisms are controlled to prevent unscheduled and toxic recombination intermediates. A unifying model to integrate these mechanisms in a dynamic, replication fork-associated process is proposed from yeast results.
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Affiliation(s)
- Félix Prado
- Department of Genome Biology, Andalusian Molecular Biology and Regenerative Medicine Center (CABIMER), CSIC-University of Seville-University Pablo de Olavide, 41092 Seville, Spain.
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12
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Chen J, Tang Q, Guo S, Lu C, Le S, Yan J. Parallel triplex structure formed between stretched single-stranded DNA and homologous duplex DNA. Nucleic Acids Res 2017; 45:10032-10041. [PMID: 28973442 PMCID: PMC5622322 DOI: 10.1093/nar/gkx628] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 07/11/2017] [Indexed: 02/01/2023] Open
Abstract
The interaction between the single-stranded DNA and the homologous duplex DNA is essential for DNA homologous repair. Here, we report that parallel triplex structure can form spontaneously between a mechanically extended ssDNA and a homologous dsDNA in protein-free condition. The triplex has a contour length close to that of a B-form DNA duplex and remains stable after force is released. The binding energy between the ssDNA and the homologous dsDNA in the triplex is estimated to be comparable to the basepairing energy in a B-form dsDNA. As ssDNA is in a similar extended conformation within recombinase-coated nucleoprotein filaments, we propose that the parallel triplex may form and serve as an intermediate during recombinase-catalyzed homologous joint formation.
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Affiliation(s)
- Jin Chen
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Qingnan Tang
- Department of Physics, National University of Singapore, 117542, Singapore
| | - Shiwen Guo
- Mechanobiology Institute, National University of Singapore, 117411, Singapore
| | - Chen Lu
- Mechanobiology Institute, National University of Singapore, 117411, Singapore.,Centre for Bioimaging Sciences, National University of Singapore, 117546, Singapore
| | - Shimin Le
- Mechanobiology Institute, National University of Singapore, 117411, Singapore.,Department of Physics, National University of Singapore, 117542, Singapore
| | - Jie Yan
- Mechanobiology Institute, National University of Singapore, 117411, Singapore.,Department of Physics, National University of Singapore, 117542, Singapore.,Centre for Bioimaging Sciences, National University of Singapore, 117546, Singapore
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13
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Human RAD52 Captures and Holds DNA Strands, Increases DNA Flexibility, and Prevents Melting of Duplex DNA: Implications for DNA Recombination. Cell Rep 2017; 18:2845-2853. [PMID: 28329678 PMCID: PMC5379009 DOI: 10.1016/j.celrep.2017.02.068] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/20/2017] [Accepted: 02/21/2017] [Indexed: 11/30/2022] Open
Abstract
Human RAD52 promotes annealing of complementary single-stranded DNA (ssDNA). In-depth knowledge of RAD52-DNA interaction is required to understand how its activity is integrated in DNA repair processes. Here, we visualize individual fluorescent RAD52 complexes interacting with single DNA molecules. The interaction with ssDNA is rapid, static, and tight, where ssDNA appears to wrap around RAD52 complexes that promote intra-molecular bridging. With double-stranded DNA (dsDNA), interaction is slower, weaker, and often diffusive. Interestingly, force spectroscopy experiments show that RAD52 alters the mechanics dsDNA by enhancing DNA flexibility and increasing DNA contour length, suggesting intercalation. RAD52 binding changes the nature of the overstretching transition of dsDNA and prevents DNA melting, which is advantageous for strand clamping during or after annealing. DNA-bound RAD52 is efficient at capturing ssDNA in trans. Together, these effects may help key steps in DNA repair, such as second-end capture during homologous recombination or strand annealing during RAD51-independent recombination reactions. RAD52 binds ssDNA rapidly and tightly using wrapping and bridging modes RAD52 binding to dsDNA is slower, weaker, and often diffusive RAD52 changes dsDNA mechanics and intercalates into the double helix RAD52 prevents DNA melting by clamping DNA strands
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14
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Shao S, Ren C, Liu Z, Bai Y, Chen Z, Wei Z, Wang X, Zhang Z, Xu K. Enhancing CRISPR/Cas9-mediated homology-directed repair in mammalian cells by expressing Saccharomyces cerevisiae Rad52. Int J Biochem Cell Biol 2017; 92:43-52. [DOI: 10.1016/j.biocel.2017.09.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 09/09/2017] [Accepted: 09/15/2017] [Indexed: 12/01/2022]
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15
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Replication fork reversal triggers fork degradation in BRCA2-defective cells. Nat Commun 2017; 8:859. [PMID: 29038466 PMCID: PMC5643541 DOI: 10.1038/s41467-017-01164-5] [Citation(s) in RCA: 268] [Impact Index Per Article: 38.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 08/22/2017] [Indexed: 01/21/2023] Open
Abstract
Besides its role in homologous recombination, the tumor suppressor BRCA2 protects stalled replication forks from nucleolytic degradation. Defective fork stability contributes to chemotherapeutic sensitivity of BRCA2-defective tumors by yet-elusive mechanisms. Using DNA fiber spreading and direct visualization of replication intermediates, we report that reversed replication forks are entry points for fork degradation in BRCA2-defective cells. Besides MRE11 and PTIP, we show that RAD52 promotes stalled fork degradation and chromosomal breakage in BRCA2-defective cells. Inactivation of these factors restores reversed fork frequency and chromosome integrity in BRCA2-defective cells. Conversely, impairing fork reversal prevents fork degradation, but increases chromosomal breakage, uncoupling fork protection, and chromosome stability. We propose that BRCA2 is dispensable for RAD51-mediated fork reversal, but assembles stable RAD51 nucleofilaments on regressed arms, to protect them from degradation. Our data uncover the physiopathological relevance of fork reversal and illuminate a complex interplay of homologous recombination factors in fork remodeling and stability. BRCA2 is involved in both homologous recombination (HR) and the protection of stalled replication forks from degradation. Here the authors reveal how HR factors cooperate in fork remodeling, showing that BRCA2 supports RAD51 loading on the regressed arms of reversed replication forks to protect them from degradation.
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16
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Manthey GM, Clear AD, Liddell LC, Negritto MC, Bailis AM. Homologous recombination in budding yeast expressing the human RAD52 gene reveals a Rad51-independent mechanism of conservative double-strand break repair. Nucleic Acids Res 2017; 45:1879-1888. [PMID: 27923995 PMCID: PMC5389729 DOI: 10.1093/nar/gkw1228] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2016] [Accepted: 11/24/2016] [Indexed: 11/12/2022] Open
Abstract
RAD52 is a homologous recombination (HR) protein that is conserved from bacteriophage to humans. Simultaneously attenuating expression of both the RAD52 gene, and the HR and tumor suppressor gene, BRCA2, in human cells synergistically reduces HR – indicating that RAD52 and BRCA2 control independent mechanisms of HR. We have expressed the human RAD52 gene (HsRAD52) in budding yeast strains lacking the endogenous RAD52 gene and found that HsRAD52 supports repair of DNA double-strand breaks (DSB) by a mechanism of HR that conserves genome structure. Importantly, this mechanism of HR is independent of RAD51, which encodes the central strand exchange protein in yeast required for conservative HR. In contrast, BRCA2 exerts its effect on HR in human cells together with HsRAD51, potentially explaining the synergistic effect of attenuating the expression of both HsRAD52 and BRCA2. This suggests that multiple mechanisms of conservative DSB repair may contribute to tumor suppression in human cells.
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Affiliation(s)
- Glenn M Manthey
- Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | - Alissa D Clear
- Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.,Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | - Lauren C Liddell
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | | | - Adam M Bailis
- Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA.,Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
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17
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Wang Z, Zhu WG, Xu X. Ubiquitin-like modifications in the DNA damage response. Mutat Res 2017; 803-805:56-75. [PMID: 28734548 DOI: 10.1016/j.mrfmmm.2017.07.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/03/2017] [Accepted: 07/03/2017] [Indexed: 12/14/2022]
Abstract
Genomic DNA is damaged at an extremely high frequency by both endogenous and environmental factors. An improper response to DNA damage can lead to genome instability, accelerate the aging process and ultimately cause various human diseases, including cancers and neurodegenerative disorders. The mechanisms that underlie the cellular DNA damage response (DDR) are complex and are regulated at many levels, including at the level of post-translational modification (PTM). Since the discovery of ubiquitin in 1975 and ubiquitylation as a form of PTM in the early 1980s, a number of ubiquitin-like modifiers (UBLs) have been identified, including small ubiquitin-like modifiers (SUMOs), neural precursor cell expressed, developmentally down-regulated 8 (NEDD8), interferon-stimulated gene 15 (ISG15), human leukocyte antigen (HLA)-F adjacent transcript 10 (FAT10), ubiquitin-fold modifier 1 (UFRM1), URM1 ubiquitin-related modifier-1 (URM1), autophagy-related protein 12 (ATG12), autophagy-related protein 8 (ATG8), fan ubiquitin-like protein 1 (FUB1) and histone mono-ubiquitylation 1 (HUB1). All of these modifiers have known roles in the cellular response to various forms of stress, and delineating their underlying molecular mechanisms and functions is fundamental in enhancing our understanding of human disease and longevity. To date, however, the molecular mechanisms and functions of these UBLs in the DDR remain largely unknown. This review summarizes the current status of PTMs by UBLs in the DDR and their implication in cancer diagnosis, therapy and drug discovery.
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Affiliation(s)
- Zhifeng Wang
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China
| | - Wei-Guo Zhu
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China
| | - Xingzhi Xu
- Guangdong Key Laboratory of Genome Stability & Disease Prevention, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China; Beijing Key Laboratory of DNA Damage Response, Capital Normal University College of Life Sciences, Beijing 100048, China.
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18
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Mazina OM, Keskin H, Hanamshet K, Storici F, Mazin AV. Rad52 Inverse Strand Exchange Drives RNA-Templated DNA Double-Strand Break Repair. Mol Cell 2017; 67:19-29.e3. [PMID: 28602639 DOI: 10.1016/j.molcel.2017.05.019] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Revised: 05/09/2017] [Accepted: 05/19/2017] [Indexed: 12/20/2022]
Abstract
RNA can serve as a template for DNA double-strand break repair in yeast cells, and Rad52, a member of the homologous recombination pathway, emerged as an important player in this process. However, the exact mechanism of how Rad52 contributes to RNA-dependent DSB repair remained unknown. Here, we report an unanticipated activity of yeast and human Rad52: inverse strand exchange, in which Rad52 forms a complex with dsDNA and promotes strand exchange with homologous ssRNA or ssDNA. We show that in eukaryotes, inverse strand exchange between homologous dsDNA and RNA is a distinctive activity of Rad52; neither Rad51 recombinase nor the yeast Rad52 paralog Rad59 has this activity. In accord with our in vitro results, our experiments in budding yeast provide evidence that Rad52 inverse strand exchange plays an important role in RNA-templated DSB repair in vivo.
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Affiliation(s)
- Olga M Mazina
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Havva Keskin
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Kritika Hanamshet
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Francesca Storici
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| | - Alexander V Mazin
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
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19
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Reappearance from Obscurity: Mammalian Rad52 in Homologous Recombination. Genes (Basel) 2016; 7:genes7090063. [PMID: 27649245 PMCID: PMC5042393 DOI: 10.3390/genes7090063] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 09/06/2016] [Accepted: 09/09/2016] [Indexed: 01/28/2023] Open
Abstract
Homologous recombination (HR) plays an important role in maintaining genomic integrity. It is responsible for repair of the most harmful DNA lesions, DNA double-strand breaks and inter-strand DNA cross-links. HR function is also essential for proper segregation of homologous chromosomes in meiosis, maintenance of telomeres, and resolving stalled replication forks. Defects in HR often lead to genetic diseases and cancer. Rad52 is one of the key HR proteins, which is evolutionarily conserved from yeast to humans. In yeast, Rad52 is important for most HR events; Rad52 mutations disrupt repair of DNA double-strand breaks and targeted DNA integration. Surprisingly, in mammals, Rad52 knockouts showed no significant DNA repair or recombination phenotype. However, recent work demonstrated that mutations in human RAD52 are synthetically lethal with mutations in several other HR proteins including BRCA1 and BRCA2. These new findings indicate an important backup role for Rad52, which complements the main HR mechanism in mammals. In this review, we focus on the Rad52 activities and functions in HR and the possibility of using human RAD52 as therapeutic target in BRCA1 and BRCA2-deficient familial breast cancer and ovarian cancer.
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20
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Abstract
The bacteriophage λ Red homologous recombination system has been studied over the past 50 years as a model system to define the mechanistic details of how organisms exchange DNA segments that share extended regions of homology. The λ Red system proved useful as a system to study because recombinants could be easily generated by co-infection of genetically marked phages. What emerged from these studies was the recognition that replication of phage DNA was required for substantial Red-promoted recombination in vivo, and the critical role that double-stranded DNA ends play in allowing the Red proteins access to the phage DNA chromosomes. In the past 16 years, however, the λ Red recombination system has gained a new notoriety. When expressed independently of other λ functions, the Red system is able to promote recombination of linear DNA containing limited regions of homology (∼50 bp) with the Escherichia coli chromosome, a process known as recombineering. This review explains how the Red system works during a phage infection, and how it is utilized to make chromosomal modifications of E. coli with such efficiency that it changed the nature and number of genetic manipulations possible, leading to advances in bacterial genomics, metabolic engineering, and eukaryotic genetics.
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Affiliation(s)
- Kenan C Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605
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21
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Huang F, Goyal N, Sullivan K, Hanamshet K, Patel M, Mazina OM, Wang CX, An WF, Spoonamore J, Metkar S, Emmitte KA, Cocklin S, Skorski T, Mazin AV. Targeting BRCA1- and BRCA2-deficient cells with RAD52 small molecule inhibitors. Nucleic Acids Res 2016; 44:4189-99. [PMID: 26873923 PMCID: PMC4872086 DOI: 10.1093/nar/gkw087] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 02/03/2016] [Indexed: 12/20/2022] Open
Abstract
RAD52 is a member of the homologous recombination (HR) pathway that is important for maintenance of genome integrity. While single RAD52 mutations show no significant phenotype in mammals, their combination with mutations in genes that cause hereditary breast cancer and ovarian cancer like BRCA1, BRCA2, PALB2 and RAD51C are lethal. Consequently, RAD52 may represent an important target for cancer therapy. In vitro, RAD52 has ssDNA annealing and DNA strand exchange activities. Here, to identify small molecule inhibitors of RAD52 we screened a 372,903-compound library using a fluorescence-quenching assay for ssDNA annealing activity of RAD52. The obtained 70 putative inhibitors were further characterized using biochemical and cell-based assays. As a result, we identified compounds that specifically inhibit the biochemical activities of RAD52, suppress growth of BRCA1- and BRCA2-deficient cells and inhibit RAD52-dependent single-strand annealing (SSA) in human cells. We will use these compounds for development of novel cancer therapy and as a probe to study mechanisms of DNA repair.
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Affiliation(s)
- Fei Huang
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Nadish Goyal
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Katherine Sullivan
- Department of Microbiology and Immunology, and Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 10140, USA
| | - Kritika Hanamshet
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Mikir Patel
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Olga M Mazina
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Charles X Wang
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - W Frank An
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - James Spoonamore
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Shailesh Metkar
- Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Kyle A Emmitte
- Vanderbilt Specialized Chemistry Center for Accelerated Probe Development, Vanderbilt Center for Neuroscience Drug Discovery, Department of Pharmacology and Chemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Simon Cocklin
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| | - Tomasz Skorski
- Department of Microbiology and Immunology, and Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 10140, USA
| | - Alexander V Mazin
- Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, Philadelphia, PA 19102, USA
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22
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Ander M, Subramaniam S, Fahmy K, Stewart AF, Schäffer E. A Single-Strand Annealing Protein Clamps DNA to Detect and Secure Homology. PLoS Biol 2015; 13:e1002213. [PMID: 26271032 PMCID: PMC4535883 DOI: 10.1371/journal.pbio.1002213] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2015] [Accepted: 06/26/2015] [Indexed: 11/24/2022] Open
Abstract
Repair of DNA breaks by single-strand annealing (SSA) is a major mechanism for the maintenance of genomic integrity. SSA is promoted by proteins (single-strand-annealing proteins [SSAPs]), such as eukaryotic RAD52 and λ phage Redβ. These proteins use a short single-stranded region to find sequence identity and initiate homologous recombination. However, it is unclear how SSAPs detect homology and catalyze annealing. Using single-molecule experiments, we provide evidence that homology is recognized by Redβ monomers that weakly hold single DNA strands together. Once annealing begins, dimerization of Redβ clamps the double-stranded region and nucleates nucleoprotein filament growth. In this manner, DNA clamping ensures and secures a successful detection for DNA sequence homology. The clamp is characterized by a structural change of Redβ and a remarkable stability against force up to 200 pN. Our findings not only present a detailed explanation for SSAP action but also identify the DNA clamp as a very stable, noncovalent, DNA-protein interaction.
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Affiliation(s)
- Marcel Ander
- Nanomechanics Group, Biotechnology Center, TU Dresden, Dresden, Germany
| | | | - Karim Fahmy
- Division of Biophysics, Institute of Resource Ecology, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - A. Francis Stewart
- Department of Genomics, Biotechnology Center, TU Dresden, Dresden, Germany
| | - Erik Schäffer
- Nanomechanics Group, Biotechnology Center, TU Dresden, Dresden, Germany
- Cellular Nanoscience, Center for Plant Molecular Biology (ZMBP), Universität Tübingen, Tübingen, Germany
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23
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Morrical SW. DNA-pairing and annealing processes in homologous recombination and homology-directed repair. Cold Spring Harb Perspect Biol 2015; 7:a016444. [PMID: 25646379 DOI: 10.1101/cshperspect.a016444] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The formation of heteroduplex DNA is a central step in the exchange of DNA sequences via homologous recombination, and in the accurate repair of broken chromosomes via homology-directed repair pathways. In cells, heteroduplex DNA largely arises through the activities of recombination proteins that promote DNA-pairing and annealing reactions. Classes of proteins involved in pairing and annealing include RecA-family DNA-pairing proteins, single-stranded DNA (ssDNA)-binding proteins, recombination mediator proteins, annealing proteins, and nucleases. This review explores the properties of these pairing and annealing proteins, and highlights their roles in complex recombination processes including the double Holliday junction (DhJ) formation, synthesis-dependent strand annealing, and single-strand annealing pathways--DNA transactions that are critical both for genome stability in individual organisms and for the evolution of species.
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Affiliation(s)
- Scott W Morrical
- Department of Biochemistry, University of Vermont College of Medicine, Burlington, Vermont 05405
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24
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Chen CF, Brill SJ. Multimerization domains are associated with apparent strand exchange activity in BLM and WRN DNA helicases. DNA Repair (Amst) 2014; 22:137-46. [PMID: 25198671 DOI: 10.1016/j.dnarep.2014.07.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 07/10/2014] [Accepted: 07/22/2014] [Indexed: 12/11/2022]
Abstract
BLM and WRN are members of the RecQ family of DNA helicases that act to suppress genome instability and cancer predisposition. In addition to a RecQ helicase domain, each of these proteins contains an N-terminal domain of approximately 500 amino acids (aa) that is incompletely characterized. Previously, we showed that the N-terminus of Sgs1, the yeast ortholog of BLM, contains a physiologically important 200 aa domain (Sgs1103-322) that displays single-stranded DNA (ssDNA) binding, strand annealing (SA), and apparent strand-exchange (SE) activities in vitro. Here we used a genetic assay to search for heterologous proteins that could functionally replace this domain of Sgs1 in vivo. In contrast to Rad59, the oligomeric Rad52 protein provided in vivo complementation, suggesting that multimerization is functionally important. An N-terminal domain of WRN was also identified that could replace Sgs1103-322 in yeast. This domain, WRN235-526, contains a known coiled coil and displays the same SA and SE activities as Sgs1103-322. The coiled coil domain of WRN235-526 is required for both its in vivo activity and its in vitro SE activity. Based on this result, a potential coiled coil was identified within Sgs1103-322. This 25 amino acid region was similarly essential for wt Sgs1 activity in vivo and was replaceable by a heterologous coiled coil. Taken together, the results indicate that a coiled coil and a closely linked apparent SE activity are conserved features of the BLM and WRN DNA helicases.
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Affiliation(s)
- Chi-Fu Chen
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, United States
| | - Steven J Brill
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, United States.
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25
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Lee M, Lee CH, Demin AA, Munashingha PR, Amangyeld T, Kwon B, Formosa T, Seo YS. Rad52/Rad59-dependent recombination as a means to rectify faulty Okazaki fragment processing. J Biol Chem 2014; 289:15064-79. [PMID: 24711454 DOI: 10.1074/jbc.m114.548388] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The correct removal of 5'-flap structures by Rad27 and Dna2 during Okazaki fragment maturation is crucial for the stable maintenance of genetic materials and cell viability. In this study, we identified RAD52, a key recombination protein, as a multicopy suppressor of dna2-K1080E, a lethal helicase-negative mutant allele of DNA2 in yeasts. In contrast, the overexpression of Rad51, which works conjointly with Rad52 in canonical homologous recombination, failed to suppress the growth defect of the dna2-K1080E mutation, indicating that Rad52 plays a unique and distinct role in Okazaki fragment metabolism. We found that the recombination-defective Rad52-QDDD/AAAA mutant did not rescue dna2-K1080E, suggesting that Rad52-mediated recombination is important for suppression. The Rad52-mediated enzymatic stimulation of Dna2 or Rad27 is not a direct cause of suppression observed in vivo, as both Rad52 and Rad52-QDDD/AAAA proteins stimulated the endonuclease activities of both Dna2 and Rad27 to a similar extent. The recombination mediator activity of Rad52 was dispensable for the suppression, whereas both the DNA annealing activity and its ability to interact with Rad59 were essential. In addition, we found that several cohesion establishment factors, including Rsc2 and Elg1, were required for the Rad52-dependent suppression of dna2-K1080E. Our findings suggest a novel Rad52/Rad59-dependent, but Rad51-independent recombination pathway that could ultimately lead to the removal of faulty flaps in conjunction with cohesion establishment factors.
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Affiliation(s)
- Miju Lee
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Chul-Hwan Lee
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Annie Albert Demin
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Palinda Ruvan Munashingha
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Tamir Amangyeld
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Buki Kwon
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
| | - Tim Formosa
- the Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112
| | - Yeon-Soo Seo
- From the Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea and
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26
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Janicka S, Kühn K, Le Ret M, Bonnard G, Imbault P, Augustyniak H, Gualberto JM. A RAD52-like single-stranded DNA binding protein affects mitochondrial DNA repair by recombination. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2012; 72:423-435. [PMID: 22762281 DOI: 10.1111/j.1365-313x.2012.05097.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The plant mitochondrial DNA-binding protein ODB1 was identified from a mitochondrial extract after DNA-affinity purification. ODB1 (organellar DNA-binding protein 1) co-purified with WHY2, a mitochondrial member of the WHIRLY family of plant-specific proteins involved in the repair of organellar DNA. The Arabidopsis thaliana ODB1 gene is identical to RAD52-1, which encodes a protein functioning in homologous recombination in the nucleus but additionally localizing to mitochondria. We confirmed the mitochondrial localization of ODB1 by in vitro and in vivo import assays, as well as by immunodetection on Arabidopsis subcellular fractions. In mitochondria, WHY2 and ODB1 were found in large nucleo-protein complexes. Both proteins co-immunoprecipitated in a DNA-dependent manner. In vitro assays confirmed DNA binding by ODB1 and showed that the protein has higher affinity for single-stranded than for double-stranded DNA. ODB1 showed no sequence specificity in vitro. In vivo, DNA co-immunoprecipitation indicated that ODB1 binds sequences throughout the mitochondrial genome. ODB1 promoted annealing of complementary DNA sequences, suggesting a RAD52-like function as a recombination mediator. Arabidopsis odb1 mutants were morphologically indistinguishable from the wild-type, but following DNA damage by genotoxic stress, they showed reduced mitochondrial homologous recombination activity. Under the same conditions, the odb1 mutants showed an increase in illegitimate repair bypasses generated by microhomology-mediated recombination. These observations identify ODB1 as a further component of homologous recombination-dependent DNA repair in plant mitochondria.
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Affiliation(s)
- Sabina Janicka
- Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Université de Strasbourg, 12 rue du Général Zimmer, 67084 Strasbourg Cedex, France
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27
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Abstract
The homologous recombination systems of linear double-stranded (ds)DNA bacteriophages are required for the generation of genetic diversity, the repair of dsDNA breaks, and the formation of concatemeric chromosomes, the immediate precursor to packaging. These systems have been studied for decades as a means to understand the basic principles of homologous recombination. From the beginning, it was recognized that these recombinases are linked intimately to the mechanisms of phage DNA replication. In the last decade, however, investigators have exploited these recombination systems as tools for genetic engineering of bacterial chromosomes, bacterial artificial chromosomes, and plasmids. This recombinational engineering technology has been termed "recombineering" and offers a new paradigm for the genetic manipulation of bacterial chromosomes, which is far more efficient than the classical use of nonreplicating integration vectors for gene replacement. The phage λ Red recombination system, in particular, has been used to construct gene replacements, deletions, insertions, inversions, duplications, and single base pair changes in the Escherichia coli chromosome. This chapter discusses the components of the recombination systems of λ, rac prophage, and phage P22 and properties of single-stranded DNA annealing proteins from these and other phage that have been instrumental for the development of this technology. The types of genetic manipulations that can be made are described, along with proposed mechanisms for both double-stranded DNA- and oligonucleotide-mediated recombineering events. Finally, the impact of this technology to such diverse fields as bacterial pathogenesis, metabolic engineering, and mouse genomics is discussed.
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Affiliation(s)
- Kenan C Murphy
- Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA, USA.
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28
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Jouvet N, Poschmann J, Douville J, Bulet L, Ramotar D. Rrd1 isomerizes RNA polymerase II in response to rapamycin. BMC Mol Biol 2010; 11:92. [PMID: 21129186 PMCID: PMC3019149 DOI: 10.1186/1471-2199-11-92] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Accepted: 12/03/2010] [Indexed: 01/11/2023] Open
Abstract
Background In Saccharomyces cerevisiae, the immunosuppressant rapamycin engenders a profound modification in the transcriptional profile leading to growth arrest. Mutants devoid of Rrd1, a protein possessing in vitro peptidyl prolyl cis/trans isomerase activity, display striking resistance to the drug, although how Rrd1 activity is linked to the biological responses has not been elucidated. Results We now provide evidence that Rrd1 is associated with the chromatin and it interacts with RNA polymerase II. Circular dichroism revealed that Rrd1 mediates structural changes onto the C-terminal domain (CTD) of the large subunit of RNA polymerase II (Rpb1) in response to rapamycin, although this appears to be independent of the overall phosphorylation status of the CTD. In vitro experiments, showed that recombinant Rrd1 directly isomerizes purified GST-CTD and that it releases RNA polymerase II from the chromatin. Consistent with this, we demonstrated that Rrd1 is required to alter RNA polymerase II occupancy on rapamycin responsive genes. Conclusion We propose as a mechanism, that upon rapamycin exposure Rrd1 isomerizes Rpb1 to promote its dissociation from the chromatin in order to modulate transcription.
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Affiliation(s)
- Nathalie Jouvet
- Maisonneuve-Rosemont Hospital, Research Center, Department of Immunology and Oncology, University of Montreal, 5415 de l'Assomption, Montreal, Quebec, Canada
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29
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Saito K, Kagawa W, Suzuki T, Suzuki H, Yokoyama S, Saitoh H, Tashiro S, Dohmae N, Kurumizaka H. The putative nuclear localization signal of the human RAD52 protein is a potential sumoylation site. J Biochem 2010; 147:833-42. [PMID: 20190268 DOI: 10.1093/jb/mvq020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
RAD52, a key factor in homologous recombination (HR), plays important roles in both RAD51-dependent and -independent HR pathways. Several studies have suggested a link between the functional regulation of RAD52 and the protein modification by a small ubiquitin-like modifier (SUMO). However, the molecular mechanism underlying the regulation of RAD52 by SUMO is unknown. To begin investigating this mechanism, we identified possible target sites for sumoylation in the human RAD52 protein by preparing a RAD52-SUMO complex using an established Escherichia coli sumoylation system. Mass spectrometry and amino acid sequencing of the enzymatically digested fragments of the purified complex revealed that the putative nuclear localization signal located near the C terminus of RAD52 was sumoylated. Biochemical studies of the RAD52-SUMO complex suggested that sumoylation at the identified site has no apparent effect on the DNA binding, D-loop formation, ssDNA annealing and RAD51-binding activities of RAD52. On the other hand, visualization of the GFP-fused RAD52 protein in the human cell that contained mutations at the identified sumoylation sites showed clear differences in the cytosolic and nuclear distributions of the protein. These results suggest the possibility of sumoylation playing an important role in the nuclear transport of RAD52.
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Affiliation(s)
- Kengo Saito
- Graduate School of Advanced Science and Engineering, Waseda University, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan
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30
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Chan CY, Schiestl RH. Rad1, rad10 and rad52 mutations reduce the increase of microhomology length during radiation-induced microhomology-mediated illegitimate recombination in saccharomyces cerevisiae. Radiat Res 2009; 172:141-51. [PMID: 19630519 DOI: 10.1667/rr1675.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Abstract Illegitimate recombination can repair DNA double-strand breaks in one of two ways, either without sequence homology or by using a few base pairs of homology at the junctions. The second process is known as microhomology-mediated recombination. Previous studies showed that ionizing radiation and restriction enzymes increase the frequency of microhomology-mediated recombination in trans during rejoining of unirradiated plasmids or during integration of plasmids into the genome. Here we show that radiation-induced microhomology-mediated recombination is reduced by deletion of RAD52, RAD1 and RAD10 but is not affected by deletion of RAD51 and RAD2. The rad52 mutant did not change the frequency of radiation-induced microhomology-mediated recombination but rather reduced the length of microhomology required to undergo repair during radiation-induced recombination. The rad1 and rad10 mutants exhibited a smaller increase in the frequency of radiation-induced microhomology-mediated recombination, and the radiation-induced integration junctions from these mutants did not show more than 4 bp of microhomology. These results suggest that Rad52 facilitates annealing of short homologous sequences during integration and that Rad1/Rad10 endonuclease mediates removal of the displaced 3' single-stranded DNA ends after base-pairing of microhomology sequences, when more than 4 bp of microhomology are used. Taken together, these results suggest that radiation-induced microhomology-mediated recombination is under the same genetic control as the single-strand annealing apparatus that requires the RAD52, RAD1 and RAD10 genes.
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Affiliation(s)
- Cecilia Y Chan
- Departments of Pathology, Environmental Health and Radiation Oncology, Geffen School of Medicine and School of Public Health, UCLA, Los Angeles, California 90095, USA
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31
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The recombination protein RAD52 cooperates with the excision repair protein OGG1 for the repair of oxidative lesions in mammalian cells. Mol Cell Biol 2009; 29:4441-54. [PMID: 19506022 DOI: 10.1128/mcb.00265-09] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Oxidized bases are common types of DNA modifications. Their accumulation in the genome is linked to aging and degenerative diseases. These modifications are commonly repaired by the base excision repair (BER) pathway. Oxoguanine DNA glycosylase (OGG1) initiates BER of oxidized purine bases. A small number of protein interactions have been identified for OGG1, while very few appear to have functional consequences. We report here that OGG1 interacts with the recombination protein RAD52 in vitro and in vivo. This interaction has reciprocal functional consequences as OGG1 inhibits RAD52 catalytic activities and RAD52 stimulates OGG1 incision activity, likely increasing its turnover rate. RAD52 colocalizes with OGG1 after oxidative stress to cultured cells, but not after the direct induction of double-strand breaks by ionizing radiation. Human cells depleted of RAD52 via small interfering RNA knockdown, and mouse cells lacking the protein via gene knockout showed increased sensitivity to oxidative stress. Moreover, cells depleted of RAD52 show higher accumulation of oxidized bases in their genome than cells with normal levels of RAD52. Our results indicate that RAD52 cooperates with OGG1 to repair oxidative DNA damage and enhances the cellular resistance to oxidative stress. Our observations suggest a coordinated action between these proteins that may be relevant when oxidative lesions positioned close to strand breaks impose a hindrance to RAD52 catalytic activities.
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32
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Mazloum N, Holloman WK. Second-end capture in DNA double-strand break repair promoted by Brh2 protein of Ustilago maydis. Mol Cell 2009; 33:160-70. [PMID: 19187759 PMCID: PMC2663533 DOI: 10.1016/j.molcel.2008.12.023] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2008] [Revised: 08/18/2008] [Accepted: 12/18/2008] [Indexed: 11/28/2022]
Abstract
Brh2 plays a central role in the homologous recombination system of Ustilago maydis, mediating delivery of Rad51 to single-stranded DNA. Here we report that Brh2 can pair the displaced strand of a D loop with a complementary single-stranded DNA to form a duplexed, or double, D loop. The reaction emulates the second-end capture step envisioned in models of DNA double-strand break repair. This second-end capture reaction promoted by Brh2 proceeds efficiently when performed in the presence of Rad51 under conditions that block annealing by Rad52, or when the second single-stranded DNA substrate is replaced by double-stranded DNA. In a coupled reaction that requires extension of the D loop more than 200 nt by DNA synthesis in order to reveal a complementary region, Brh2 was also able to promote second-end capture and thus model a synthesis-dependent strand-annealing mechanism.
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Affiliation(s)
- Nayef Mazloum
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10021
| | - William K. Holloman
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10021
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33
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Kagawa W, Kagawa A, Saito K, Ikawa S, Shibata T, Kurumizaka H, Yokoyama S. Identification of a second DNA binding site in the human Rad52 protein. J Biol Chem 2008; 283:24264-73. [PMID: 18593704 DOI: 10.1074/jbc.m802204200] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rad52 plays essential roles in homology-dependent double-strand break repair. Various studies have established the functions of Rad52 in Rad51-dependent and Rad51-independent repair processes. However, the precise molecular mechanisms of Rad52 in these processes remain unknown. In the present study we have identified a novel DNA binding site within Rad52 by a structure-based alanine scan mutagenesis. This site is closely aligned with the putative single-stranded DNA binding site determined previously. Mutations in this site impaired the ability of the Rad52-single-stranded DNA complex to form a ternary complex with double-stranded DNA and subsequently catalyze the formation of D-loops. We found that Rad52 introduces positive supercoils into double-stranded DNA and that the second DNA binding site is essential for this activity. Our findings suggest that Rad52 aligns two recombining DNA molecules within the first and second DNA binding sites to stimulate the homology search and strand invasion processes.
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Affiliation(s)
- Wataru Kagawa
- RIKEN Systems and Structural Biology Center, 1-7-22 Suehiro-cho, Tsurumi, Yokohama, Japan
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34
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The Rad52 homologs Rad22 and Rti1 of Schizosaccharomyces pombe are not essential for meiotic interhomolog recombination, but are required for meiotic intrachromosomal recombination and mating-type-related DNA repair. Genetics 2008; 178:2399-412. [PMID: 18430957 DOI: 10.1534/genetics.107.085696] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Proteins of the RAD52 epistasis group play an essential role in repair of some types of DNA damage and genetic recombination. In Schizosaccharomyces pombe, Rad22 (a Rad52 ortholog) has been shown to be as necessary for repair and recombination events during vegetative growth as its Saccharomyces cerevisiae counterpart. This finding contrasts with previous reports where, due to suppressor mutations in the fbh1 gene, rad22 mutants did not display a severe defect. We have analyzed the roles of Rad22 and Rti1, another Rad52 homolog, during meiotic recombination and meiosis in general. Both proteins play an important role in spore viability. During meiotic prophase I, they partially colocalize and partially localize to Rad51 foci and linear elements. Genetic analysis showed that meiotic interchromosomal crossover and conversion events were unexpectedly not much affected by deletion of either or both genes. A strong decrease of intrachromosomal recombination assayed by a gene duplication construct was observed. Therefore, we propose that the most important function of Rad22 and Rti1 in S. pombe meiosis is repair of double-strand breaks with involvement of the sister chromatids. In addition, a novel mating-type-related repair function of Rad22 specific to meiosis and spore germination is described.
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35
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Kojic M, Mao N, Zhou Q, Lisby M, Holloman WK. Compensatory role for Rad52 during recombinational repair in Ustilago maydis. Mol Microbiol 2008; 67:1156-68. [PMID: 18208529 DOI: 10.1111/j.1365-2958.2008.06116.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A single Rad52-related protein is evident by blast analysis of the Ustilago maydis genome database. Mutants created by disruption of the structural gene exhibited few discernible defects in resistance to UV, ionizing radiation, chemical alkylating or cross-linking agents. No deficiency was noted in spontaneous mutator activity, allelic recombination or meiosis. GFP-Rad51 foci were formed in rad52 cells following DNA damage, but were initially less intense than normal suggesting a possible role for Rad52 in formation of the Rad51 nucleoprotein filament. A search for interacting genes that confer a synthetic fitness phenotype with rad52 after DNA damage by UV irradiation identified the genes for Mph1, Ercc1 and the Rad51 paralogue Rec2. Testing known mutants in recombinational repair revealed an additional interaction with the BRCA2 orthologue Brh2. Suppression of the rec2 mutant's UV sensitivity by overexpressing Brh2 was found to be dependent on Rad52. The results suggest that Rad52 serves in an overlapping, compensatory role with both Rec2 and Brh2 to promote and maintain formation of the Rad51 nucleoprotein filament.
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Affiliation(s)
- Milorad Kojic
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10065, USA
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36
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Abstract
Brh2, the ortholog of the BRCA2 tumor suppressor in Ustilago maydis, works hand in hand with Rad51 to promote repair of DNA by homologous recombination. Previous studies established that Brh2 can stimulate DNA strand exchange by enabling Rad51 nucleoprotein filament formation on replication protein A-coated ssDNA. But, more recently, it was noted that Brh2 has an inherent DNA annealing activity, raising the notion that it might have roles in recombination in addition to or beyond the mediator function. Here, we found that Brh2 can autonomously promote the formation of D-loops in reactions with plasmid DNA and homologous single-stranded oligonucleotides. The reaction differs from that catalyzed by Rad51 in having no requirement for cofactors or preloading phase on ssDNA. D-loop formation was most effective when Brh2 was mixed with plasmid DNA before addition of single-stranded oligomer. D-loop formation catalyzed by Rad51 was also enhanced when Brh2 was premixed with plasmid DNA. Brh2 rendered defective in Rad51 interaction by mutation in the BRC element was still capable of promoting D-loop formation. However, the mutant protein was unable to enhance the Rad51-catalyzed reaction. The results suggest a model in which Brh2 binding to plasmid DNA attracts and helps capture Rad51-coated ssDNA.
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37
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Mazloum N, Zhou Q, Holloman WK. DNA binding, annealing, and strand exchange activities of Brh2 protein from Ustilago maydis. Biochemistry 2007; 46:7163-73. [PMID: 17523678 PMCID: PMC2553723 DOI: 10.1021/bi700399m] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Brh2 is the Ustilago maydis ortholog of the BRCA2 tumor suppressor. It functions in repair of DNA by homologous recombination by controlling the action of Rad51. A critical aspect in the control appears to be the recruitment of Rad51 to single-stranded DNA regions exposed as lesions after damage or following a disturbance in DNA synthesis. In previous experimentation, Brh2 was shown to nucleate formation of the Rad51 nucleoprotein filament that becomes the active element in promoting homologous pairing and DNA strand exchange. Nucleation was found to be initiated at junctions of double-stranded and single-stranded DNA. Here we investigated the DNA binding specificity of Brh2 in more detail using oligonucleotide substrates. We observed that Brh2 prefers partially duplex structures with single-stranded branches, flaps, or D-loops. We found also that Brh2 has an inherent ability to promote DNA annealing and strand exchange reactions on free as well as RPA-coated substrates. Unlike Rad51, Brh2 was able to promote DNA strand exchange when preincubated with double-stranded DNA. These findings raise the notion that Brh2 may have roles in homologous recombination beyond the previously established Rad51 mediator activity.
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Affiliation(s)
- Nayef Mazloum
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10021
| | - Qingwen Zhou
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10021
| | - William K. Holloman
- Department of Microbiology and Immunology, Cornell University Weill Medical College, New York, NY 10021
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38
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Thorpe PH, Marrero VA, Savitzky MH, Sunjevaric I, Freeman TC, Rothstein R. Cells expressing murine RAD52 splice variants favor sister chromatid repair. Mol Cell Biol 2006; 26:3752-63. [PMID: 16648471 PMCID: PMC1488992 DOI: 10.1128/mcb.26.10.3752-3763.2006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The RAD52 gene is essential for homologous recombination in the yeast Saccharomyces cerevisiae. RAD52 is the archetype in an epistasis group of genes essential for DNA damage repair. By catalyzing the replacement of replication protein A with Rad51 on single-stranded DNA, Rad52 likely promotes strand invasion of a double-stranded DNA molecule by single-stranded DNA. Although the sequence and in vitro functions of mammalian RAD52 are conserved with those of yeast, one difference is the presence of introns and consequent splicing of the mammalian RAD52 pre-mRNA. We identified two novel splice variants from the RAD52 gene that are expressed in adult mouse tissues. Expression of these splice variants in tissue culture cells elevates the frequency of recombination that uses a sister chromatid template. To characterize this dominant phenotype further, the RAD52 gene from the yeast Saccharomyces cerevisiae was truncated to model the mammalian splice variants. The same dominant sister chromatid recombination phenotype seen in mammalian cells was also observed in yeast. Furthermore, repair from a homologous chromatid is reduced in yeast, implying that the choice of alternative repair pathways may be controlled by these variants. In addition, a dominant DNA repair defect induced by one of the variants in yeast is suppressed by overexpression of RAD51, suggesting that the Rad51-Rad52 interaction is impaired.
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Affiliation(s)
- Peter H Thorpe
- Department of Genetics and Development, Columbia University Medical Center, HHSC 1608, 701 West 168th St., New York, New York 10032, USA
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39
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Singh RK, Krishna M. DNA strand breaks signal the induction of DNA double-strand break repair in Saccharomyces cerevisiae. Radiat Res 2006; 164:781-90. [PMID: 16296884 DOI: 10.1667/rr3460.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Genotoxic stress induces a checkpoint signaling cascade to generate a stress response. Saccharomyces cerevisiae shows an altered radiation response under different type of stress. Although the induction of repair has been implicated in enhanced survival after exposure to the challenging stress, the nature of the signal remains poorly understood. This study demonstrates that low doses of gamma radiation and bleomycin induce RAD52-dependent recombination repair pathway in the wild-type strain D-261. Prior exposure of cells to DNA-damaging agents (gamma radiation or bleomycin) equips them better for the subsequent damage caused by challenging doses. However, exposure to UV light, which does not cause strand breaks, was ineffective. This was confirmed by PFGE studies. This indicates that the strand breaks probably serve as the signal for induction of the recombination repair pathway while pyrimidine dimers do not. The nature of the induced repair was investigated by mutation scoring in special strain D-7, which showed that the induced repair is essentially error free.
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Affiliation(s)
- Rakesh Kumar Singh
- Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai, India 400085.
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40
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Adachi N, Iiizumi S, Koyama H. Evidence for a role of vertebrate Rad52 in the repair of topoisomerase II-mediated DNA damage. DNA Cell Biol 2005; 24:388-93. [PMID: 15941391 DOI: 10.1089/dna.2005.24.388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
DNA topoisomerase II (Top2) inhibitors are useful as anticancer agents, mostly by virtue of their ability to induce DNA double-strand breaks (DSBs). These DSBs are repaired almost exclusively by Rad52-dependent homologous recombination (HR) in yeast. However, we have recently shown that in vertebrate cells such lesions are primarily repaired by nonhomologous end-joining, but not HR. This finding, taken together with previous observations that disruption of RAD52 does not severely affect HR in vertebrate cells, makes it highly unlikely that Rad52 contributes to the repair of Top2-mediated DNA damage. However, in this paper we show that chicken cells lacking Rad52 do exhibit increased sensitivity to the Top2 inhibitor VP-16. Remarkably, the level of hypersensitivity of RAD52-null cells was comparable to that of RAD54-null cells, albeit only at high doses. Our data thus provide the first demonstration of a major repair defect associated with loss of Rad52 in vertebrate cells.
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Affiliation(s)
- Noritaka Adachi
- Kihara Institute for Biological Research, Graduate School of Integrated Science, Yokohama City University, Yokohama, Japan.
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41
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Di Primio C, Galli A, Cervelli T, Zoppè M, Rainaldi G. Potentiation of gene targeting in human cells by expression of Saccharomyces cerevisiae Rad52. Nucleic Acids Res 2005; 33:4639-48. [PMID: 16106043 PMCID: PMC1187822 DOI: 10.1093/nar/gki778] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
When exogenous DNA is stably introduced in mammalian cells, it is typically integrated in random positions, and only a minor fraction enters a pathway of homologous recombination (HR). The complex Rad51/Rad52 is a major player in the management of exogenous DNA in eukaryotic organisms and plays a critical role in the choice of repair system. In Saccharomyces cerevisiae, the pathway of choice is HR, mediated by Rad52 (ScRad52), which differs slightly from its human homologue. Here, we present an approach that utilizes ScRad52 to enhance HR in human cells containing a specific substrate for recombination. Clones of HeLa cells were produced expressing functional ScRad52. These cells showed enhanced resistance to DNA damaging treatments and revealed a different distribution of Rad51 foci (a marker of recombination complex formation). More significantly, ScRad52 expression resulted in an up to 37-fold increase in gene targeting by HR. In the same cells, random integration of exogenous DNA was significantly reduced, consistent with the view that HR and non-homologous end joining are alternative competing pathways. Expression of ScRad52 could offer a major improvement for experiments requiring gene targeting by HR, both in basic research and in gene therapy studies.
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Affiliation(s)
| | | | | | | | - Giuseppe Rainaldi
- To whom correspondence should be addressed. Tel: +39 050 3153108; Fax: +39 050 3153327;
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42
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Current awareness on yeast. Yeast 2005; 22:71-8. [PMID: 15685779 DOI: 10.1002/yea.1157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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43
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Rybalchenko N, Golub EI, Bi B, Radding CM. Strand invasion promoted by recombination protein beta of coliphage lambda. Proc Natl Acad Sci U S A 2004; 101:17056-60. [PMID: 15574500 PMCID: PMC535401 DOI: 10.1073/pnas.0408046101] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Studies of phage lambda in vivo have indicated that its own recombination enzymes, beta protein and lambda exonuclease, are capable of catalyzing two dissimilar pathways of homologous recombination that are widely distributed in nature: single-strand annealing and strand invasion. The former is an enzymatic splicing of overlapping ends of broken homologous DNA molecules, whereas the latter is characterized by the formation of a three-stranded synaptic intermediate and subsequent strand exchange. Previous studies in vitro have shown that beta protein has annealing activity, and that lambda exonuclease, acting on branched substrates, can produce a perfect splice that requires only ligation for completion. The present study shows that beta protein can initiate strand invasion in vitro, as evidenced both by the formation of displacement loops (D-loops) in superhelical DNA and by strand exchange between colinear single-stranded and double-stranded molecules. Thus, beta protein can catalyze steps that are central to both strand annealing and strand invasion pathways of recombination. These observations add beta protein to a set of diverse proteins that appear to promote recognition of homology by a unitary mechanism governed by the intrinsic dynamic properties of base pairs in DNA.
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Affiliation(s)
- Nataliya Rybalchenko
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
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44
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Brozmanová J, Vlcková V, Chovanec M. How heterologously expressed Escherichia coli genes contribute to understanding DNA repair processes in Saccharomyces cerevisiae. Curr Genet 2004; 46:317-30. [PMID: 15614491 DOI: 10.1007/s00294-004-0536-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2004] [Revised: 09/13/2004] [Accepted: 09/18/2004] [Indexed: 10/26/2022]
Abstract
DNA-damaging agents constantly challenge cellular DNA; and efficient DNA repair is therefore essential to maintain genome stability and cell viability. Several DNA repair mechanisms have evolved and these have been shown to be highly conserved from bacteria to man. DNA repair studies were originally initiated in very simple organisms such as Escherichia coli and Saccharomyces cerevisiae, bacteria being the best understood organism to date. As a consequence, bacterial DNA repair genes encoding proteins with well characterized functions have been transferred into higher organisms in order to increase repair capacity, or to complement repair defects, in heterologous cells. While indicating the contribution of these repair functions to protection against the genotoxic effects of DNA-damaging agents, heterologous expression studies also highlighted the role of the DNA lesions that are substrates for such processes. In addition, bacterial DNA repair-like functions could be identified in higher organisms using this approach. We heterologously expressed three well characterized E. coli repair genes in S. cerevisiae cells of different genetic backgrounds: (1) the ada gene encoding O(6)-methylguanine DNA-methyltransferase, a protein involved in the repair of alkylation damage to DNA, (2) the recA gene encoding the main recombinase in E. coli and (3) the nth gene, the product of which (endonuclease III) is responsible for the repair of oxidative base damage. Here, we summarize our results and indicate the possible implications they have for a better understanding of particular DNA repair processes in S. cerevisiae.
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Affiliation(s)
- Jela Brozmanová
- Laboratory of Molecular Genetics, Cancer Research Institute, Vlárska 7, 83391 Bratislava, Slovak Republic.
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45
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Folta-Stogniew E, O'Malley S, Gupta R, Anderson KS, Radding CM. Exchange of DNA base pairs that coincides with recognition of homology promoted by E. coli RecA protein. Mol Cell 2004; 15:965-75. [PMID: 15383285 DOI: 10.1016/j.molcel.2004.08.017] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2004] [Revised: 06/06/2004] [Accepted: 07/01/2004] [Indexed: 11/26/2022]
Abstract
The unresolved mechanism by which a single strand of DNA recognizes homology in duplex DNA is central to understanding genetic recombination and repair of double-strand breaks. Using stopped-flow fluorescence we monitored strand exchange catalyzed by E. coli RecA protein, measuring simultaneously the rate of exchange of A:T base pairs and the rates of formation and dissociation of the three-stranded intermediates called synaptic complexes. The rate of exchange of A:T base pairs was indistinguishable from the rate of formation of synaptic complexes, whereas the rate of displacement of a single strand from complexes was five to ten times slower. This physical evidence shows that a subset of bases exchanges at a rate that is fast enough to account for recognition of homology. Together, several studies suggest that a mechanism governed by the dynamic structure of DNA and catalyzed by diverse enzymes underlies both recognition of homology and initiation of strand exchange.
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Affiliation(s)
- Ewa Folta-Stogniew
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06510, USA
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Doe CL, Osman F, Dixon J, Whitby MC. DNA repair by a Rad22-Mus81-dependent pathway that is independent of Rhp51. Nucleic Acids Res 2004; 32:5570-81. [PMID: 15486206 PMCID: PMC524275 DOI: 10.1093/nar/gkh853] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In budding yeast most Rad51-dependent and -independent recombination depends on Rad52. In contrast, its homologue in fission yeast, Rad22, was assumed to play a less critical role possibly due to functional redundancy with another Rad52-like protein Rti1. We show here that this is not the case. Rad22 like Rad52 plays a central role in recombination being required for both Rhp51-dependent and -independent events. Having established this we proceed to investigate the involvement of the Mus81-Eme1 endonuclease in these pathways. Mus81 plays a relatively minor role in the Rhp51-dependent repair of DNA damage induced by ultraviolet light. In contrast Mus81 has a key role in the Rad22-dependent (Rhp51-independent) repair of damage induced by camptothecin, hydroxyurea and methyl-methanesulfonate. Furthermore, spontaneous intrachromosomal recombination that gives rise to deletion recombinants is impaired in a mus81 mutant. From these data we propose that a Rad22-Mus81-dependent (Rhp51-independent) pathway is an important mechanism for the repair of DNA damage in fission yeast. Consistent with this we show that in vitro Rad22 can promote strand invasion to form a D-loop that can be cleaved by Mus81.
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Affiliation(s)
- Claudette L Doe
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK
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Kumar JK, Gupta RC. Strand exchange activity of human recombination protein Rad52. Proc Natl Acad Sci U S A 2004; 101:9562-7. [PMID: 15205484 PMCID: PMC470714 DOI: 10.1073/pnas.0403416101] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Repair of double-strand breaks is essential for the maintenance of genome integrity and cell survival. In eukaryotes, double-strand-break repair by homologous recombination requires the Rad52 group of proteins. Human Rad52 protein (HsRad52)-mediated annealing of complementary strands has been studied in detail, but little has been reported on the recombinase activities of HsRad52. For this study, we purified HsRad52 from Escherichia coli. DNase I protection experiments indicated that HsRad52 binds preferentially to single-stranded DNA and protects it against digestion by DNase I. HsRad52 catalyzed D-loop formation in superhelical DNA, as well as strand exchange among oligonucleotide substrates. The formation of a stoichiometric complex between HsRad52 and single-stranded DNA was found to be critical for strand exchange activity, and the coating of both the single- and double-stranded oligonucleotides inhibited the exchange reaction.
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Affiliation(s)
- Jaspal K Kumar
- Department of Biological Sciences, University at Albany, State University of New York, 1400 Washington Avenue, Albany, NY 12222, USA
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