1
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Joshi S, Dash S, Vijayan N, Nishant KT. Irc20 modulates LOH frequency and distribution in S. cerevisiae. DNA Repair (Amst) 2024; 141:103727. [PMID: 39098164 DOI: 10.1016/j.dnarep.2024.103727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 06/04/2024] [Accepted: 07/09/2024] [Indexed: 08/06/2024]
Abstract
Loss of Heterozygosity (LOH) due to mitotic recombination is frequently associated with the development of various cancers (e.g. retinoblastoma). LOH is also an important source of genetic diversity, especially in organisms where meiosis is infrequent. Irc20 is a putative helicase, and E3 ubiquitin ligase involved in DNA double-strand break repair pathway. We analyzed genome-wide LOH events, gross chromosomal changes, small insertion-deletions and single nucleotide mutations in eleven S. cerevisiae mutation accumulation lines of irc20∆, which underwent 50 mitotic bottlenecks. LOH enhancement in irc20∆ was small (1.6 fold), but statistically significant as compared to the wild type. Short (≤ 1 kb) and long (> 10 kb) LOH tracts were significantly enhanced in irc20∆. Both interstitial and terminal LOH events were also significantly enhanced in irc20∆ compared to the wild type. LOH events in irc20∆ were more telomere proximal and away from centromeres compared to the wild type. Gross chromosomal changes, single nucleotide mutations and in-dels were comparable between irc20∆ and wild type. Locus based and genome-wide analysis of meiotic recombination showed that meiotic crossover frequencies are not altered in irc20∆. These results suggest Irc20 primarily regulates mitotic recombination and does not affect meiotic crossovers. Our results suggest that the IRC20 gene is important for regulating LOH frequency and distribution.
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Affiliation(s)
- Sameer Joshi
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Trivandrum 695551, India
| | - Suman Dash
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Trivandrum 695551, India
| | - Nikilesh Vijayan
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Trivandrum 695551, India
| | - Koodali T Nishant
- School of Biology, Indian Institute of Science Education and Research Thiruvananthapuram, Trivandrum 695551, India; Center for High-Performance Computing, Indian Institute of Science Education and Research Thiruvananthapuram, Trivandrum 695551, India.
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2
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Muhammad AA, Basto C, Peterlini T, Guirouilh-Barbat J, Thomas M, Veaute X, Busso D, Lopez B, Mazon G, Le Cam E, Masson JY, Dupaigne P. Human RAD52 stimulates the RAD51-mediated homology search. Life Sci Alliance 2024; 7:e202201751. [PMID: 38081641 PMCID: PMC10713436 DOI: 10.26508/lsa.202201751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 12/01/2023] [Accepted: 12/01/2023] [Indexed: 12/18/2023] Open
Abstract
Homologous recombination (HR) is a DNA repair mechanism of double-strand breaks and blocked replication forks, involving a process of homology search leading to the formation of synaptic intermediates that are regulated to ensure genome integrity. RAD51 recombinase plays a central role in this mechanism, supported by its RAD52 and BRCA2 partners. If the mediator function of BRCA2 to load RAD51 on RPA-ssDNA is well established, the role of RAD52 in HR is still far from understood. We used transmission electron microscopy combined with biochemistry to characterize the sequential participation of RPA, RAD52, and BRCA2 in the assembly of the RAD51 filament and its activity. Although our results confirm that RAD52 lacks a mediator activity, RAD52 can tightly bind to RPA-coated ssDNA, inhibit the mediator activity of BRCA2, and form shorter RAD51-RAD52 mixed filaments that are more efficient in the formation of synaptic complexes and D-loops, resulting in more frequent multi-invasions as well. We confirm the in situ interaction between RAD51 and RAD52 after double-strand break induction in vivo. This study provides new molecular insights into the formation and regulation of presynaptic and synaptic intermediates by BRCA2 and RAD52 during human HR.
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Affiliation(s)
- Ali Akbar Muhammad
- Genome Integrity and Cancers UMR 9019 CNRS, Université Paris- Saclay, Gustave Roussy, Villejuif Cedex, France
| | - Clara Basto
- Genome Integrity and Cancers UMR 9019 CNRS, Université Paris- Saclay, Gustave Roussy, Villejuif Cedex, France
| | - Thibaut Peterlini
- Genome Stability Laboratory, CHU de Quebec Research Center, HDQ Pavilion, Oncology Axis, Quebec City, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University, Quebec City, Canada
| | - Josée Guirouilh-Barbat
- https://ror.org/02vjkv261 INSERM U1016, UMR 8104 CNRS, Institut Cochin, Equipe Labellisée Ligue Contre le Cancer, Université de Paris, Paris, France
| | - Melissa Thomas
- Genome Stability Laboratory, CHU de Quebec Research Center, HDQ Pavilion, Oncology Axis, Quebec City, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University, Quebec City, Canada
| | - Xavier Veaute
- https://ror.org/02vjkv261 CIGEx Platform, INSERM, IRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Université de Paris and Université Paris-Saclay, Fontenay-aux-Roses, France
| | - Didier Busso
- https://ror.org/02vjkv261 CIGEx Platform, INSERM, IRCM/IBFJ CEA, UMR Stabilité Génétique Cellules Souches et Radiations, Université de Paris and Université Paris-Saclay, Fontenay-aux-Roses, France
| | - Bernard Lopez
- https://ror.org/02vjkv261 INSERM U1016, UMR 8104 CNRS, Institut Cochin, Equipe Labellisée Ligue Contre le Cancer, Université de Paris, Paris, France
| | - Gerard Mazon
- Genome Integrity and Cancers UMR 9019 CNRS, Université Paris- Saclay, Gustave Roussy, Villejuif Cedex, France
| | - Eric Le Cam
- Genome Integrity and Cancers UMR 9019 CNRS, Université Paris- Saclay, Gustave Roussy, Villejuif Cedex, France
| | - Jean-Yves Masson
- Genome Stability Laboratory, CHU de Quebec Research Center, HDQ Pavilion, Oncology Axis, Quebec City, Canada
- Department of Molecular Biology, Medical Biochemistry and Pathology, Laval University, Quebec City, Canada
| | - Pauline Dupaigne
- Genome Integrity and Cancers UMR 9019 CNRS, Université Paris- Saclay, Gustave Roussy, Villejuif Cedex, France
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3
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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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4
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Meir A, Raina VB, Rivera CE, Marie L, Symington LS, Greene EC. The separation pin distinguishes the pro- and anti-recombinogenic functions of Saccharomyces cerevisiae Srs2. Nat Commun 2023; 14:8144. [PMID: 38065943 PMCID: PMC10709652 DOI: 10.1038/s41467-023-43918-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
Srs2 is an Sf1a helicase that helps maintain genome stability in Saccharomyces cerevisiae through its ability to regulate homologous recombination. Srs2 downregulates HR by stripping Rad51 from single-stranded DNA, and Srs2 is also thought to promote synthesis-dependent strand annealing by unwinding D-loops. However, it has not been possible to evaluate the relative contributions of these two distinct activities to any aspect of recombination. Here, we used a structure-based approach to design an Srs2 separation-of-function mutant that can dismantle Rad51-ssDNA filaments but is incapable of disrupting D-loops, allowing us to assess the relative contributions of these pro- and anti-recombinogenic functions. We show that this separation-of-function mutant phenocopies wild-type SRS2 in vivo, suggesting that the ability of Srs2 to remove Rad51 from ssDNA is its primary role during HR.
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Affiliation(s)
- Aviv Meir
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY, 10032, USA
| | - Vivek B Raina
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY, 10032, USA
| | - Carly E Rivera
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY, 10032, USA
| | - Léa Marie
- Department of Microbiology & Immunology, Columbia University, New York, NY, 10032, USA
- Institute of Pharmacology and Structural Biology (IPBS), French National Centre for Scientific Research (CNRS), Université Toulouse III, Toulouse, France
| | - Lorraine S Symington
- Department of Microbiology & Immunology, Columbia University, New York, NY, 10032, USA
- Department of Genetics & Development, Columbia University, New York, NY, 10032, USA
| | - Eric C Greene
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY, 10032, USA.
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5
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Cargemel C, Baconnais S, Aumont-Nicaise M, Noiray M, Maurin L, Andreani J, Walbott H, Le Cam E, Ochsenbein F, Marsin S, Quevillon-Cheruel S. Structural Insights of the DciA Helicase Loader in Its Relationship with DNA. Int J Mol Sci 2023; 24:ijms24021427. [PMID: 36674944 PMCID: PMC9865707 DOI: 10.3390/ijms24021427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 01/15/2023] Open
Abstract
DciA is the ancestral bacterial replicative helicase loader, punctually replaced during evolution by the DnaC/I loaders of phage origin. DnaC helps the helicase to load onto DNA by cracking open the hexameric ring, but the mechanism of loading by DciA remains unknown. We demonstrate by electron microscopy, nuclear magnetic resonance (NMR) spectroscopy, and biochemistry experiments that DciA, which folds into a KH-like domain, interacts with not only single-stranded but also double-stranded DNA, in an atypical mode. Some point mutations of the long α-helix 1 demonstrate its importance in the interaction of DciA for various DNA substrates mimicking single-stranded, double-stranded, and forked DNA. Some of these mutations also affect the loading of the helicase by DciA. We come to the hypothesis that DciA could be a DNA chaperone by intercalating itself between the two DNA strands to stabilize it. This work allows us to propose that the direct interaction of DciA with DNA could play a role in the loading mechanism of the helicase.
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Affiliation(s)
- Claire Cargemel
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Sonia Baconnais
- Genome Integrity and Cancer UMR 9019 CNRS, Université Paris Saclay, Gustave Roussy, 114 Rue Edouard Vaillant, 94805 Villejuif, France
| | - Magali Aumont-Nicaise
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Magali Noiray
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Lia Maurin
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Jessica Andreani
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Hélène Walbott
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Eric Le Cam
- Genome Integrity and Cancer UMR 9019 CNRS, Université Paris Saclay, Gustave Roussy, 114 Rue Edouard Vaillant, 94805 Villejuif, France
| | - Françoise Ochsenbein
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Stéphanie Marsin
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
- Correspondence: (S.M.); (S.Q.-C.)
| | - Sophie Quevillon-Cheruel
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
- Correspondence: (S.M.); (S.Q.-C.)
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6
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Evstyukhina TA, Alekseeva EA, Fedorov DV, Peshekhonov VT, Korolev VG. Genetic Analysis of the Hsm3 Protein Function in Yeast Saccharomyces cerevisiae NuB4 Complex. Genes (Basel) 2021; 12:1083. [PMID: 34356099 PMCID: PMC8307810 DOI: 10.3390/genes12071083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/09/2021] [Accepted: 07/15/2021] [Indexed: 11/16/2022] Open
Abstract
In the nuclear compartment of yeast, NuB4 core complex consists of three proteins, Hat1, Hat2, and Hif1, and interacts with a number of other factors. In particular, it was shown that NuB4 complex physically interacts with Hsm3p. Early we demonstrated that the gene HSM3 participates in the control of replicative and reparative spontaneous mutagenesis, and that hsm3Δ mutants increase the frequency of mutations induced by different mutagens. It was previously believed that the HSM3 gene controlled only some minor repair processes in the cell, but later it was suggested that it had a chaperone function with its participation in proteasome assembly. In this work, we analyzed the properties of three hsm3Δ, hif1Δ, and hat1Δ mutants. The results obtained showed that the Hsm3 protein may be a functional subunit of NuB4 complex. It has been shown that hsm3- and hif1-dependent UV-induced mutagenesis is completely suppressed by inactivation of the Polη polymerase. We showed a significant role of Polη for hsm3-dependent mutagenesis at non-bipyrimidine sites (NBP sites). The efficiency of expression of RNR (RiboNucleotid Reducase) genes after UV irradiation in hsm3Δ and hif1Δ mutants was several times lower than in wild-type cells. Thus, we have presented evidence that significant increase in the dNTP levels suppress hsm3- and hif1-dependent mutagenesis and Polη is responsible for hsm3- and hif1-dependent mutagenesis.
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Affiliation(s)
- Tatiyana A. Evstyukhina
- Laboratory of Eukaryotic Genetics, Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 188300 Gatchina, Russia; (T.A.E.); (D.V.F.); (V.T.P.); (V.G.K.)
- Laboratory of Molecular Genetic and Recombination Technologies, Kurchatov Genome Center—Petersburg Nuclear Physics Institute, mkr. Orlova Roscha 1, Leningrad District, 188300 Gatchina, Russia
| | - Elena A. Alekseeva
- Laboratory of Eukaryotic Genetics, Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 188300 Gatchina, Russia; (T.A.E.); (D.V.F.); (V.T.P.); (V.G.K.)
- Laboratory of Molecular Genetic and Recombination Technologies, Kurchatov Genome Center—Petersburg Nuclear Physics Institute, mkr. Orlova Roscha 1, Leningrad District, 188300 Gatchina, Russia
| | - Dmitriy V. Fedorov
- Laboratory of Eukaryotic Genetics, Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 188300 Gatchina, Russia; (T.A.E.); (D.V.F.); (V.T.P.); (V.G.K.)
| | - Vyacheslav T. Peshekhonov
- Laboratory of Eukaryotic Genetics, Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 188300 Gatchina, Russia; (T.A.E.); (D.V.F.); (V.T.P.); (V.G.K.)
- Laboratory of Molecular Genetic and Recombination Technologies, Kurchatov Genome Center—Petersburg Nuclear Physics Institute, mkr. Orlova Roscha 1, Leningrad District, 188300 Gatchina, Russia
| | - Vladimir G. Korolev
- Laboratory of Eukaryotic Genetics, Department of Molecular and Radiation Biophysics, Petersburg Nuclear Physics Institute Named by B.P. Konstantinov of National Research Centre “Kurchatov Institute”, 188300 Gatchina, Russia; (T.A.E.); (D.V.F.); (V.T.P.); (V.G.K.)
- Laboratory of Molecular Genetic and Recombination Technologies, Kurchatov Genome Center—Petersburg Nuclear Physics Institute, mkr. Orlova Roscha 1, Leningrad District, 188300 Gatchina, Russia
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7
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Rad52 Oligomeric N-Terminal Domain Stabilizes Rad51 Nucleoprotein Filaments and Contributes to Their Protection against Srs2. Cells 2021; 10:cells10061467. [PMID: 34207997 PMCID: PMC8230603 DOI: 10.3390/cells10061467] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 02/04/2023] Open
Abstract
Homologous recombination (HR) depends on the formation of a nucleoprotein filament of the recombinase Rad51 to scan the genome and invade the homologous sequence used as a template for DNA repair synthesis. Therefore, HR is highly accurate and crucial for genome stability. Rad51 filament formation is controlled by positive and negative factors. In Saccharomyces cerevisiae, the mediator protein Rad52 catalyzes Rad51 filament formation and stabilizes them, mostly by counteracting the disruptive activity of the translocase Srs2. Srs2 activity is essential to avoid the formation of toxic Rad51 filaments, as revealed by Srs2-deficient cells. We previously reported that Rad52 SUMOylation or mutations disrupting the Rad52–Rad51 interaction suppress Rad51 filament toxicity because they disengage Rad52 from Rad51 filaments and reduce their stability. Here, we found that mutations in Rad52 N-terminal domain also suppress the DNA damage sensitivity of Srs2-deficient cells. Structural studies showed that these mutations affect the Rad52 oligomeric ring structure. Overall, in vivo and in vitro analyzes of these mutants indicate that Rad52 ring structure is important for protecting Rad51 filaments from Srs2, but can increase Rad51 filament stability and toxicity in Srs2-deficient cells. This stabilization function is distinct from Rad52 mediator and annealing activities.
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8
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Ribeiro J, Dupaigne P, Petrillo C, Ducrot C, Duquenne C, Veaute X, Saintomé C, Busso D, Guerois R, Martini E, Livera G. The meiosis-specific MEIOB-SPATA22 complex cooperates with RPA to form a compacted mixed MEIOB/SPATA22/RPA/ssDNA complex. DNA Repair (Amst) 2021; 102:103097. [PMID: 33812231 DOI: 10.1016/j.dnarep.2021.103097] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 12/30/2022]
Abstract
During meiosis, programmed double-strand breaks are repaired by homologous recombination (HR) to form crossovers that are essential to homologous chromosome segregation. Single-stranded DNA (ssDNA) containing intermediates are key features of HR, which must be highly regulated. RPA, the ubiquitous ssDNA binding complex, was thought to play similar roles during mitotic and meiotic HR until the recent discovery of MEIOB and its partner, SPATA22, two essential meiosis-specific proteins. Here, we show that like MEIOB, SPATA22 resembles RPA subunits and binds ssDNA. We studied the physical and functional interactions existing between MEIOB, SPATA22, and RPA, and show that MEIOB and SPATA22 interact with the preformed RPA complex through their interacting domain and condense RPA-coated ssDNA in vitro. In meiotic cells, we show that MEIOB and SPATA22 modify the immunodetection of the two large subunits of RPA. Given these results, we propose that MEIOB-SPATA22 and RPA form a functional ssDNA-interacting complex to satisfy meiotic HR requirements by providing specific properties to the ssDNA.
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Affiliation(s)
- Jonathan Ribeiro
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France
| | - Pauline Dupaigne
- Laboratoire de Microscopie Moléculaire et Cellulaire, UMR 8126, Interactions Moléculaires et Cancer, CNRS, Université Paris Sud, Institut de Cancérologie Gustave Roussy, Villejuif, France
| | - Cynthia Petrillo
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France
| | - Cécile Ducrot
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France
| | - Clotilde Duquenne
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France
| | - Xavier Veaute
- CIGEx, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université de Paris, Université Paris-Saclay, CEA, Inserm, U1274, F-92260, Fontenay-aux-Roses, France
| | - Carole Saintomé
- MNHN, CNRS UMR 7196, INSERM U1154, Sorbonne Universités, 75231, Paris, France
| | - Didier Busso
- CIGEx, UMRE008 Stabilité Génétique Cellules Souches et Radiations, Université de Paris, Université Paris-Saclay, CEA, Inserm, U1274, F-92260, Fontenay-aux-Roses, France
| | - Raphaël Guerois
- CNRS I2BC UMR 9198, iBiTec-S, SB²SM CEA SACLAY, 91191, Gif sur Yvette, France
| | - Emmanuelle Martini
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France.
| | - Gabriel Livera
- Laboratory of Development of the Gonads, UMR E008 Genetic Stability Stem Cells and Radiations, Université de Paris, Université Paris Saclay, CEA, F-92265, Fontenay aux Roses, France
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9
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Abstract
In this issue of Molecular Cell, Roy et al. (2021) and Belan et al. (2021) demonstrate that the yeast and nematode RAD51 paralog complexes function as chaperones to promote the assembly of the RAD51 nucleoprotein filament on RPA-coated ssDNA.
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Affiliation(s)
- Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, 6500, Switzerland; Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH) Zürich, 8093, Switzerland.
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10
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Jalal D, Chalissery J, Iqbal M, Hassan AH. The ATPase Irc20 facilitates Rad51 chromatin enrichment during homologous recombination in yeast Saccharomyces cerevisiae. DNA Repair (Amst) 2020; 97:103019. [PMID: 33202365 DOI: 10.1016/j.dnarep.2020.103019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Revised: 11/02/2020] [Accepted: 11/05/2020] [Indexed: 10/23/2022]
Abstract
DNA double-strand breaks (DSBs) constitute one of the most cytotoxic forms of DNA damage and pose a significant threat to cell viability, survival, and homeostasis. DSBs have the potential to promote aneuploidy, cell death and potentially deleterious mutations that promote tumorigenesis. Homologous recombination (HR) is one of the main DSB repair pathways and while being essential for cell survival under genotoxic stress, it requires proper regulation to avoid chromosome rearrangements. Here, we characterize the Saccharomyces cerevisiae E3 ubiquitin ligase/putative helicase Irc20 as a regulator of HR. Using purified Irc20, we show that it can hydrolyze ATP in the presence and absence of DNA, but does not increase access to DNA within a nucleosome. In addition, we show that both the ATPase and ubiquitin ligase activities of Irc20 are required for suppressing the spontaneous formation of recombination foci. Finally, we demonstrate a role for Irc20 in promoting Rad51 chromatin association and the removal of Rad52 recombinase from chromatin, thus facilitating subsequent HR steps and directing recombination to more error-free modes.
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Affiliation(s)
- Deena Jalal
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Jisha Chalissery
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Mehwish Iqbal
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates
| | - Ahmed H Hassan
- Department of Biochemistry, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al-Ain, United Arab Emirates.
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11
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Participation of the HIM1 gene of yeast Saccharomyces cerevisiae in the error-free branch of post-replicative repair and role Polη in him1-dependent mutagenesis. Curr Genet 2020; 67:141-151. [PMID: 33128582 PMCID: PMC7886746 DOI: 10.1007/s00294-020-01115-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/29/2020] [Accepted: 10/01/2020] [Indexed: 12/04/2022]
Abstract
In eukaryotes, DNA damage tolerance (DDT) is determined by two repair pathways, homologous repair recombination (HRR) and a pathway controlled by the RAD6-epistatic group of genes. Monoubiquitylation of PCNA mediates an error-prone pathway, whereas polyubiquitylation stimulates an error-free pathway. The error-free pathway involves components of recombination repair; however, the factors that act in this pathway remain largely unknown. Here, we report that the HIM1 gene participates in error-free DDT. Notably, inactivation RAD30 gene encoding Polη completely suppresses him1-dependent UV mutagenesis. Furthermore, data obtained show a significant role of Polη in him1-dependent mutagenesis, especially at non-bipyrimidine sites (NBP sites). We demonstrate that him1 mutation significantly reduces the efficiency of the induction expression of RNR genes after UV irradiation. Besides, this paper presents evidence that significant increase in the dNTP levels suppress him1-dependent mutagenesis. Our findings show that Polη responsible for him1-dependent mutagenesis.
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12
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Benureau Y, Moreira Tavares E, Muhammad AA, Baconnais S, Le Cam E, Dupaigne P. Method combining BAC film and positive staining for the characterization of DNA intermediates by dark-field electron microscopy. Biol Methods Protoc 2020; 5:bpaa012. [PMID: 32913896 PMCID: PMC7474861 DOI: 10.1093/biomethods/bpaa012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 11/15/2022] Open
Abstract
DNA intermediate structures are formed in all major pathways of DNA metabolism. Transmission electron microscopy (TEM) is a tool of choice to study their choreography and has led to major advances in the understanding of these mechanisms, particularly those of homologous recombination (HR) and replication. In this article, we describe specific TEM procedures dedicated to the structural characterization of DNA intermediates formed during these processes. These particular DNA species contain single-stranded DNA regions and/or branched structures, which require controlling both the DNA molecules spreading and their staining for subsequent visualization using dark-field imaging mode. Combining BAC (benzyl dimethyl alkyl ammonium chloride) film hyperphase with positive staining and dark-field TEM allows characterizing synthetic DNA substrates, joint molecules formed during not only in vitro assays mimicking HR, but also in vivo DNA intermediates.
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Affiliation(s)
- Yann Benureau
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
- UMR9019-CNRS, Genome Integrity and Cancer, Equipe labellisée Ligue contre le Cancer, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Eliana Moreira Tavares
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Ali-Akbar Muhammad
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Sonia Baconnais
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
| | - Eric Le Cam
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
- Correspondence address. DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France. Tel: 00 33 1 42 11 48 76 and 00 33 1 42 11 48 74; E-mail:
| | - Pauline Dupaigne
- DSB Repair, Replication Stress and Genome Integrity, UMR9019-CNRS ‘Genome Integrity and Cancer’, CNRS, Université Paris-Saclay, Gustave Roussy, F-94805, Villejuif Cedex, France
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13
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Sandhu R, Monge Neria F, Monge Neria J, Chen X, Hollingsworth NM, Börner GV. DNA Helicase Mph1 FANCM Ensures Meiotic Recombination between Parental Chromosomes by Dissociating Precocious Displacement Loops. Dev Cell 2020; 53:458-472.e5. [PMID: 32386601 PMCID: PMC7386354 DOI: 10.1016/j.devcel.2020.04.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 02/09/2020] [Accepted: 04/10/2020] [Indexed: 02/07/2023]
Abstract
Meiotic pairing between parental chromosomes (homologs) is required for formation of haploid gametes. Homolog pairing depends on recombination initiation via programmed double-strand breaks (DSBs). Although DSBs appear prior to pairing, the homolog, rather than the sister chromatid, is used as repair partner for crossing over. Here, we show that Mph1, the budding yeast ortholog of Fanconi anemia helicase FANCM, prevents precocious DSB strand exchange between sister chromatids before homologs have completed pairing. By dissociating precocious DNA displacement loops (D-loops) between sister chromatids, Mph1FANCM ensures high levels of crossovers and non-crossovers between homologs. Later-occurring recombination events are protected from Mph1-mediated dissociation by synapsis protein Zip1. Increased intersister repair in absence of Mph1 triggers a shift among remaining interhomolog events from non-crossovers to crossover-specific strand exchange, explaining Mph1's apparent anti-crossover function. Our findings identify temporal coordination between DSB strand exchange and homolog pairing as a critical determinant for recombination outcome.
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Affiliation(s)
- Rima Sandhu
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Francisco Monge Neria
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Jesús Monge Neria
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA
| | - Xiangyu Chen
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - Nancy M Hollingsworth
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794, USA
| | - G Valentin Börner
- Center for Gene Regulation in Health and Disease and Department of Biological Sciences, Cleveland State University, Cleveland, OH 44115, USA; Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA; Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
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14
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Aouida M, Eshrif A, Ramotar D. Yeast Lacking the PP2A Phosphatase Regulatory Subunit Rts1 Sensitizes rad51 Mutants to Specific DNA Damaging Agents. Front Genet 2019; 10:1117. [PMID: 31781172 PMCID: PMC6857479 DOI: 10.3389/fgene.2019.01117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 10/16/2019] [Indexed: 11/13/2022] Open
Abstract
Rts1 is a regulatory subunit of the trimeric protein phosphatase 2A phosphatase and it participates in many biological processes by modulating the phosphorylation status of proteins. Consistent with its role, mutants lacking Rts1 display multiple phenotypes. We have previously performed a high throughput screen to search for yeast haploid mutants with altered sensitivity to the anticancer drug bleomycin, which acts by damaging the DNA to produce single and double strand breaks. RTS1 was among the genes that when singly deleted cause sensitivity to bleomycin. We investigate whether Rts1 plays a role in the repair of bleomycin-induced DNA lesions. We show that deletion of the RTS1 gene in the rad51 null background, lacking Rad51 known to be involved in the repair of bleomycin-induced DNA lesions, resulted in double mutants that were sensitized to bleomycin and not to other DNA damaging agents that creates DNA adducts. We further show that Rts1 has the ability to bind to DNA and in its absence cells displayed an increase in the frequency of both spontaneous and bleomycin-induced mutations compared to the parent. This is the first report implicating Rts1 with a role in DNA damage and repair, perhaps regulating the phosphorylation status of one or more proteins involved in the repair of DNA strand breaks.
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Affiliation(s)
- Mustapha Aouida
- College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Qatar Foundation, Doha, Qatar
| | - Abdelmoez Eshrif
- Maisonneuve-Rosemont Hospital, Research Center, Department of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Dindial Ramotar
- College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Qatar Foundation, Doha, Qatar.,Maisonneuve-Rosemont Hospital, Research Center, Department of Medicine, Université de Montréal, Montréal, QC, Canada
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15
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Jenkins SS, Gore S, Guo X, Liu J, Ede C, Veaute X, Jinks-Robertson S, Kowalczykowski SC, Heyer WD. Role of the Srs2-Rad51 Interaction Domain in Crossover Control in Saccharomyces cerevisiae. Genetics 2019; 212:1133-1145. [PMID: 31142613 PMCID: PMC6707447 DOI: 10.1534/genetics.119.302337] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 05/22/2019] [Indexed: 02/05/2023] Open
Abstract
Saccharomyces cerevisiae Srs2, in addition to its well-documented antirecombination activity, has been proposed to play a role in promoting synthesis-dependent strand annealing (SDSA). Here we report the identification and characterization of an SRS2 mutant with a single amino acid substitution (srs2-F891A) that specifically affects the Srs2 pro-SDSA function. This residue is located within the Srs2-Rad51 interaction domain and embedded within a protein sequence resembling a BRC repeat motif. The srs2-F891A mutation leads to a complete loss of interaction with Rad51 as measured through yeast two-hybrid analysis and a partial loss of interaction as determined through protein pull-down assays with purified Srs2, Srs2-F891A, and Rad51 proteins. Even though previous work has shown that internal deletions of the Srs2-Rad51 interaction domain block Srs2 antirecombination activity in vitro, the Srs2-F891A mutant protein, despite its weakened interaction with Rad51, exhibits no measurable defect in antirecombination activity in vitro or in vivo Surprisingly, srs2-F891A shows a robust shift from noncrossover to crossover repair products in a plasmid-based gap repair assay, but not in an ectopic physical recombination assay. Our findings suggest that the Srs2 C-terminal Rad51 interaction domain is more complex than previously thought, containing multiple interaction sites with unique effects on Srs2 activity.
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Affiliation(s)
- Shirin S Jenkins
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
| | - Steven Gore
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
| | - Xiaoge Guo
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina 27710
| | - Jie Liu
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
| | - Christopher Ede
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
| | - Xavier Veaute
- CEA, CIGEx, F-92265 Fontenay-aux-Roses Cedex, France
| | - Sue Jinks-Robertson
- Department of Molecular Genetics and Microbiology, Duke University, Durham, North Carolina 27710
| | - Stephen C Kowalczykowski
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
| | - Wolf-Dietrich Heyer
- Department of Microbiology and Molecular Genetics, University of California, Davis, California 95616
- Department of Molecular and Cellular Biology, University of California, Davis, California 95616
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16
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Hunt LJ, Ahmed EA, Kaur H, Ahuja JS, Hulme L, Chou TC, Lichten M, Goldman ASH. S. cerevisiae Srs2 helicase ensures normal recombination intermediate metabolism during meiosis and prevents accumulation of Rad51 aggregates. Chromosoma 2019; 128:249-265. [PMID: 31069484 PMCID: PMC6823294 DOI: 10.1007/s00412-019-00705-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/04/2019] [Accepted: 04/24/2019] [Indexed: 01/06/2023]
Abstract
We investigated the meiotic role of Srs2, a multi-functional DNA helicase/translocase that destabilises Rad51-DNA filaments and is thought to regulate strand invasion and prevent hyper-recombination during the mitotic cell cycle. We find that Srs2 activity is required for normal meiotic progression and spore viability. A significant fraction of srs2 mutant cells progress through both meiotic divisions without separating the bulk of their chromatin, although in such cells sister centromeres often separate. Undivided nuclei contain aggregates of Rad51 colocalised with the ssDNA-binding protein RPA, suggesting the presence of persistent single-strand DNA. Rad51 aggregate formation requires Spo11-induced DSBs, Rad51 strand-invasion activity and progression past the pachytene stage of meiosis, but not the DSB end-resection or the bias towards interhomologue strand invasion characteristic of normal meiosis. srs2 mutants also display altered meiotic recombination intermediate metabolism, revealed by defects in the formation of stable joint molecules. We suggest that Srs2, by limiting Rad51 accumulation on DNA, prevents the formation of aberrant recombination intermediates that otherwise would persist and interfere with normal chromosome segregation and nuclear division.
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Affiliation(s)
- Laura J Hunt
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK.,Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Brighton, BN1 9RQ, UK
| | - Emad A Ahmed
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK.,Immunology and Molecular Physiology Lab., Zoology Department, Faculty of Science, Assiut University, Markaz El-Fath, 71515, Egypt
| | - Hardeep Kaur
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA.,Department of Biochemistry and Structural Biology, UT Health San Antonio, San Antonio, TX, 78229, USA
| | - Jasvinder S Ahuja
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Lydia Hulme
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK
| | - Ta-Chung Chou
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK.,All First Tech Co., Ltd, 32467, No 146-2. Hung Chun Road, Ping Zhen Dist, Taoyuan City, Taiwan
| | - Michael Lichten
- Laboratory of Biochemistry and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892, USA
| | - Alastair S H Goldman
- Department of Molecular Biology and Biotechnology, The University of Sheffield, Sheffield, S10 2TN, UK. .,Faculty of Life Sciences, The University of Bradford, Bradford, BD7 1AZ, UK.
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17
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Recombinases and Related Proteins in the Context of Homologous Recombination Analyzed by Molecular Microscopy. Methods Mol Biol 2019; 1805:251-270. [PMID: 29971722 DOI: 10.1007/978-1-4939-8556-2_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Transmission electron microscopy (TEM) and atomic force microscopy (AFM) are powerful tools to study the behavior of various actors in homologous recombination including molecular motors such as recombinases and helicases/translocases. Here we present specific approaches developed in terms of sample preparation and imaging methods to contribute to the understanding of homologous recombination process and its regulation focusing on the interplay between recombinases and other related proteins such as mediators or antirecombinase actors.Homologous recombination (HR) is a high-fidelity DNA repair pathway since it uses a homologous DNA as template. Recombinases such as RecA in bacteria, RadA in archaea, and Rad51 in eukaryotes are key proteins in the HR pathway: HR is initiated with formation of an ssDNA overhang on which recombinases polymerize and form a dynamic active nucleoprotein filament able to search for homology and to exchange DNA strand in an ATP-dependent manner. We provide practical methods to analyze presynaptic filament formation on ssDNA, its composition and regulation in presence of mediator partners, antirecombinase activity of translocase, and chromatin remodeling events.
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18
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Jalan M, Oehler J, Morrow CA, Osman F, Whitby MC. Factors affecting template switch recombination associated with restarted DNA replication. eLife 2019; 8:41697. [PMID: 30667359 PMCID: PMC6358216 DOI: 10.7554/elife.41697] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 01/21/2019] [Indexed: 12/19/2022] Open
Abstract
Homologous recombination helps ensure the timely completion of genome duplication by restarting collapsed replication forks. However, this beneficial function is not without risk as replication restarted by homologous recombination is prone to template switching (TS) that can generate deleterious genome rearrangements associated with diseases such as cancer. Previously we established an assay for studying TS in Schizosaccharomyces pombe (Nguyen et al., 2015). Here, we show that TS is detected up to 75 kb downstream of a collapsed replication fork and can be triggered by head-on collision between the restarted fork and RNA Polymerase III transcription. The Pif1 DNA helicase, Pfh1, promotes efficient restart and also suppresses TS. A further three conserved helicases (Fbh1, Rqh1 and Srs2) strongly suppress TS, but there is no change in TS frequency in cells lacking Fml1 or Mus81. We discuss how these factors likely influence TS.
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Affiliation(s)
- Manisha Jalan
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Judith Oehler
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Carl A Morrow
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Fekret Osman
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Matthew C Whitby
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
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19
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Meiosis-specific recombinase Dmc1 is a potent inhibitor of the Srs2 antirecombinase. Proc Natl Acad Sci U S A 2018; 115:E10041-E10048. [PMID: 30301803 DOI: 10.1073/pnas.1810457115] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cross-over recombination products are a hallmark of meiosis because they are necessary for accurate chromosome segregation and they also allow for increased genetic diversity during sexual reproduction. However, cross-overs can also cause gross chromosomal rearrangements and are therefore normally down-regulated during mitotic growth. The mechanisms that enhance cross-over product formation upon entry into meiosis remain poorly understood. In Saccharomyces cerevisiae, the Superfamily 1 (Sf1) helicase Srs2, which is an ATP hydrolysis-dependent motor protein that actively dismantles recombination intermediates, promotes synthesis-dependent strand annealing, the result of which is a reduction in cross-over recombination products. Here, we show that the meiosis-specific recombinase Dmc1 is a potent inhibitor of Srs2. Biochemical and single-molecule assays demonstrate that Dmc1 acts by inhibiting Srs2 ATP hydrolysis activity, which prevents the motor protein from undergoing ATP hydrolysis-dependent translocation on Dmc1-bound recombination intermediates. We propose a model in which Dmc1 helps contribute to cross-over formation during meiosis by antagonizing the antirecombinase activity of Srs2.
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20
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The Main Role of Srs2 in DNA Repair Depends on Its Helicase Activity, Rather than on Its Interactions with PCNA or Rad51. mBio 2018; 9:mBio.01192-18. [PMID: 30018112 PMCID: PMC6050964 DOI: 10.1128/mbio.01192-18] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Homologous recombination (HR) is a mechanism that repairs a variety of DNA lesions. Under certain circumstances, however, HR can generate intermediates that can interfere with other cellular processes such as DNA transcription or replication. Cells have therefore developed pathways that abolish undesirable HR intermediates. The Saccharomyces cerevisiae yeast Srs2 helicase has a major role in one of these pathways. Srs2 also works during DNA replication and interacts with the clamp PCNA. The relative importance of Srs2’s helicase activity, Rad51 removal function, and PCNA interaction in genome stability remains unclear. We created a new SRS2 allele [srs2(1-850)] that lacks the whole C terminus, containing the interaction site for Rad51 and PCNA and interactions with many other proteins. Thus, the new allele encodes an Srs2 protein bearing only the activity of the DNA helicase. We find that the interactions of Srs2 with Rad51 and PCNA are dispensable for the main role of Srs2 in the repair of DNA damage in vegetative cells and for proper completion of meiosis. On the other hand, it has been shown that in cells impaired for the DNA damage tolerance (DDT) pathways, Srs2 generates toxic intermediates that lead to DNA damage sensitivity; we show that this negative Srs2 activity requires the C terminus of Srs2. Dissection of the genetic interactions of the srs2(1-850) allele suggest a role for Srs2’s helicase activity in sister chromatid cohesion. Our results also indicate that Srs2’s function becomes more central in diploid cells. Homologous recombination (HR) is a key mechanism that repairs damaged DNA. However, this process has to be tightly regulated; failure to regulate it can lead to genome instability. The Srs2 helicase is considered a regulator of HR; it was shown to be able to evict the recombinase Rad51 from DNA. Cells lacking Srs2 exhibit sensitivity to DNA-damaging agents, and in some cases, they display defects in DNA replication. The relative roles of the helicase and Rad51 removal activities of Srs2 in genome stability remain unclear. To address this question, we created a new Srs2 mutant which has only the DNA helicase domain. Our study shows that only the DNA helicase domain is needed to deal with DNA damage and assist in DNA replication during vegetative growth and in meiosis. Thus, our findings shift the view on the role of Srs2 in the maintenance of genome integrity.
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21
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Ma E, Dupaigne P, Maloisel L, Guerois R, Le Cam E, Coïc E. Rad52-Rad51 association is essential to protect Rad51 filaments against Srs2, but facultative for filament formation. eLife 2018; 7:32744. [PMID: 29985128 PMCID: PMC6056232 DOI: 10.7554/elife.32744] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 06/30/2018] [Indexed: 12/24/2022] Open
Abstract
Homology search and strand exchange mediated by Rad51 nucleoprotein filaments are key steps of the homologous recombination process. In budding yeast, Rad52 is the main mediator of Rad51 filament formation, thereby playing an essential role. The current model assumes that Rad51 filament formation requires the interaction between Rad52 and Rad51. However, we report here that Rad52 mutations that disrupt this interaction do not affect γ-ray- or HO endonuclease-induced gene conversion frequencies. In vivo and in vitro studies confirmed that Rad51 filaments formation is not affected by these mutations. Instead, we found that Rad52-Rad51 association makes Rad51 filaments toxic in Srs2-deficient cells after exposure to DNA damaging agents, independently of Rad52 role in Rad51 filament assembly. Importantly, we also demonstrated that Rad52 is essential for protecting Rad51 filaments against dissociation by the Srs2 DNA translocase. Our findings open new perspectives in the understanding of the role of Rad52 in eukaryotes.
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Affiliation(s)
- Emilie Ma
- DRF, IBFJ, iRCM, CEA, Fontenay-aux-Roses, France.,Université Paris-Saclay, Paris, France
| | - Pauline Dupaigne
- Université Paris-Saclay, Paris, France.,Signalisation, Noyaux et Innovation en Cancérologie, Institut Gustave Roussy, CNRS UMR 8126, Villejuif, France.,Université Paris-Sud, Orsay, France
| | - Laurent Maloisel
- DRF, IBFJ, iRCM, CEA, Fontenay-aux-Roses, France.,Université Paris-Saclay, Paris, France
| | - Raphaël Guerois
- Université Paris-Saclay, Paris, France.,Université Paris-Sud, Orsay, France.,DRF, i2BC, LBSR, CEA, Gif-sur-Yvette, France
| | - Eric Le Cam
- Université Paris-Saclay, Paris, France.,Signalisation, Noyaux et Innovation en Cancérologie, Institut Gustave Roussy, CNRS UMR 8126, Villejuif, France.,Université Paris-Sud, Orsay, France
| | - Eric Coïc
- DRF, IBFJ, iRCM, CEA, Fontenay-aux-Roses, France.,Université Paris-Saclay, Paris, France
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22
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Bhattacharjee S, Nandi S. Synthetic lethality in DNA repair network: A novel avenue in targeted cancer therapy and combination therapeutics. IUBMB Life 2018; 69:929-937. [PMID: 29171189 DOI: 10.1002/iub.1696] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 11/05/2017] [Indexed: 11/06/2022]
Abstract
Synthetic lethality refers to a lethal phenotype that results from the simultaneous disruptions of two genes, while the disruption of either gene alone is viable. Many DNA double strand break repair (DSBR) genes have synthetic lethal relationships with oncogenes and tumor suppressor genes, which can be exploited for targeted cancer therapy, an approach referred to as combination therapy. DNA double-strand breaks (DSBs) are one of the most toxic lesions to a cell and can be repaired by non-homologous end joining (NHEJ) or homologous recombination (HR). HR and NHEJ genes are particularly attractive targets for cancer therapy because these genes have altered expression patterns in cancer cells when compared with normal cells and these genetic abnormalities can be targeted for selectively killing cancer cells. Here, we review recent advances in the development of small molecule inhibitors against HR and NHEJ genes to induce synthetic lethality and address the future directions and clinical relevance of this approach. © 2017 IUBMB Life, 69(12):929-937, 2017.
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Affiliation(s)
| | - Saikat Nandi
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
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23
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Samach A, Gurevich V, Avivi-Ragolsky N, Levy AA. The effects of AtRad52 over-expression on homologous recombination in Arabidopsis. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 95:30-40. [PMID: 29667244 DOI: 10.1111/tpj.13927] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2017] [Revised: 03/20/2018] [Accepted: 03/22/2018] [Indexed: 06/08/2023]
Abstract
AtRad52 homologs are involved in DNA recombination and repair, but their precise functions in different homologous recombination (HR) pathways or in gene-targeting have not been analyzed. In order to facilitate our analyses, we generated an AtRad52-1A variant that had a stronger nuclear localization than the native gene thanks to the removal of the transit peptide for mitochondrial localization and to the addition of a nuclear localization signal. Over-expression of this variant increased HR in the nucleus, compared with the native AtRad52-1A: it increased intra-chromosomal recombination and synthesis-dependent strand-annealing HR repair rates; but conversely, it repressed the single-strand annealing pathway. The effect of AtRad52-1A over-expression on gene-targeting was tested with and without the expression of small RNAs generated from an RNAi construct containing homology to the target and donor sequences. True gene-targeting events at the Arabidopsis Cruciferin locus were obtained only when combining AtRad52-1A over-expression and target/donor-specific RNAi. This suggests that sequence-specific small RNAs might be involved in AtRad52-1A-mediated HR.
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Affiliation(s)
- Aviva Samach
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Vyacheslav Gurevich
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Naomi Avivi-Ragolsky
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Avraham A Levy
- Department of Plant and Environmental Sciences, The Weizmann Institute of Science, Rehovot, Israel
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24
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Yeast Srs2 Helicase Promotes Redistribution of Single-Stranded DNA-Bound RPA and Rad52 in Homologous Recombination Regulation. Cell Rep 2018; 21:570-577. [PMID: 29045827 DOI: 10.1016/j.celrep.2017.09.073] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 09/06/2017] [Accepted: 09/22/2017] [Indexed: 12/20/2022] Open
Abstract
Srs2 is a super-family 1 helicase that promotes genome stability by dismantling toxic DNA recombination intermediates. However, the mechanisms by which Srs2 remodels or resolves recombination intermediates remain poorly understood. Here, single-molecule imaging is used to visualize Srs2 in real time as it acts on single-stranded DNA (ssDNA) bound by protein factors that function in recombination. We demonstrate that Srs2 is highly processive and translocates rapidly (∼170 nt per second) in the 3'→5' direction along ssDNA saturated with replication protein A (RPA). We show that RPA is evicted from DNA during the passage of Srs2. Remarkably, Srs2 also readily removes the recombination mediator Rad52 from RPA-ssDNA and, in doing so, promotes rapid redistribution of both Rad52 and RPA. These findings have important mechanistic implications for understanding how Srs2 and related nucleic acid motor proteins resolve potentially pathogenic nucleoprotein intermediates.
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25
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Kaniecki K, De Tullio L, Gibb B, Kwon Y, Sung P, Greene EC. Dissociation of Rad51 Presynaptic Complexes and Heteroduplex DNA Joints by Tandem Assemblies of Srs2. Cell Rep 2017; 21:3166-3177. [PMID: 29241544 PMCID: PMC5734666 DOI: 10.1016/j.celrep.2017.11.047] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/22/2017] [Accepted: 11/13/2017] [Indexed: 12/20/2022] Open
Abstract
Srs2 is a superfamily 1 (SF1) helicase and antirecombinase that is required for genome integrity. However, the mechanisms that regulate Srs2 remain poorly understood. Here, we visualize Srs2 as it acts upon single-stranded DNA (ssDNA) bound by the Rad51 recombinase. We demonstrate that Srs2 is a processive translocase capable of stripping thousands of Rad51 molecules from ssDNA at a rate of ∼50 monomers/s. We show that Srs2 is recruited to RPA clusters embedded between Rad51 filaments and that multimeric arrays of Srs2 assemble during translocation on ssDNA through a mechanism involving iterative Srs2 loading events at sites cleared of Rad51. We also demonstrate that Srs2 acts on heteroduplex DNA joints through two alternative pathways, both of which result in rapid disruption of the heteroduplex intermediate. On the basis of these findings, we present a model describing the recruitment and regulation of Srs2 as it acts upon homologous recombination intermediates.
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Affiliation(s)
- Kyle Kaniecki
- Department of Genetics & Development, Columbia University, New York, NY 10032, USA
| | - Luisina De Tullio
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA; Centro de Investigaciones en Química Biológica de Córdoba (CIQUIBIC), CONICET, Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba, X5000 HUA, Argentina
| | - Bryan Gibb
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Youngho Kwon
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Patrick Sung
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Eric C Greene
- Department of Biochemistry & Molecular Biophysics, Columbia University, New York, NY 10032, USA.
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26
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Structural basis for the substrate selectivity of Helicobacter pylori NucT nuclease activity. PLoS One 2017; 12:e0189049. [PMID: 29206236 PMCID: PMC5714352 DOI: 10.1371/journal.pone.0189049] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 11/19/2017] [Indexed: 12/20/2022] Open
Abstract
The Phospholipase D (PLD) superfamily of proteins includes a group of enzymes with nuclease activity on various nucleic acid substrates. Here, with the aim of better understanding the substrate specificity determinants in this subfamily, we have characterised the enzymatic activity and the crystal structure of NucT, a nuclease implicated in Helicobacter pylori purine salvage and natural transformation and compared them to those of its bacterial and mammalian homologues. NucT exhibits an endonuclease activity with a strong preference for single stranded nucleic acids substrates. We identified histidine124 as essential for the catalytic activity of the protein. Comparison of the NucT crystal structure at 1.58 Å resolution reported here with those of other members of the sub-family suggests that the specificity of NucT for single-stranded nucleic acids is provided by the width of a positively charged groove giving access to the catalytic site.
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27
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Break-induced replication promotes formation of lethal joint molecules dissolved by Srs2. Nat Commun 2017; 8:1790. [PMID: 29176630 PMCID: PMC5702615 DOI: 10.1038/s41467-017-01987-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 10/27/2017] [Indexed: 12/20/2022] Open
Abstract
Break-induced replication (BIR) is a DNA double-strand break repair pathway that leads to genomic instabilities similar to those observed in cancer. BIR proceeds by a migrating bubble where asynchrony between leading and lagging strand synthesis leads to accumulation of long single-stranded DNA (ssDNA). It remains unknown how this ssDNA is prevented from unscheduled pairing with the template, which can lead to genomic instability. Here, we propose that uncontrolled Rad51 binding to this ssDNA promotes formation of toxic joint molecules that are counteracted by Srs2. First, Srs2 dislodges Rad51 from ssDNA preventing promiscuous strand invasions. Second, it dismantles toxic intermediates that have already formed. Rare survivors in the absence of Srs2 rely on structure-specific endonucleases, Mus81 and Yen1, that resolve toxic joint-molecules. Overall, we uncover a new feature of BIR and propose that tight control of ssDNA accumulated during this process is essential to prevent its channeling into toxic structures threatening cell viability. Break-induced replication (BIR) is a double-strand break repair pathway that can lead to genomic instability. Here the authors show that the absence of Srs2 helicase during BIR leads to uncontrolled binding of Rad51 to single-stranded DNA, which promotes the formation of toxic intermediates that need to be resolved by Mus81 or Yen1.
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28
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Niu H, Klein HL. Multifunctional roles of Saccharomyces cerevisiae Srs2 protein in replication, recombination and repair. FEMS Yeast Res 2017; 17:fow111. [PMID: 28011904 DOI: 10.1093/femsyr/fow111] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/22/2016] [Indexed: 11/12/2022] Open
Abstract
The Saccharomyces cerevisiae Srs2 DNA helicase has important roles in DNA replication, recombination and repair. In replication, Srs2 aids in repair of gaps by repair synthesis by preventing gaps from being used to initiate recombination. This is considered to be an anti-recombination role. In recombination, Srs2 plays both prorecombination and anti-recombination roles to promote the synthesis-dependent strand annealing recombination pathway and to inhibit gaps from initiating homologous recombination. In repair, the Srs2 helicase actively promotes gap repair through an interaction with the Exo1 nuclease to enlarge a gap for repair and to prevent Rad51 protein from accumulating on single-stranded DNA. Finally, Srs2 helicase can unwind hairpin-forming repeat sequences to promote replication and prevent repeat instability. The Srs2 activities can be controlled by phosphorylation, SUMO modification and interaction with key partners at DNA damage or lesions sites, which include PCNA and Rad51. These interactions can also limit DNA polymerase function during recombinational repair independent of the Srs2 translocase or helicase activity, further highlighting the importance of the Srs2 protein in regulating recombination. Here we review the myriad roles of Srs2 that have been documented in genome maintenance and distinguish between the translocase, helicase and additional functions of the Srs2 protein.
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Affiliation(s)
- Hengyao Niu
- Department of Molecular and Cellular Biochemistry, Indiana University, Bloomington, IN 47405, USA
| | - Hannah L Klein
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA
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29
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Liu J, Ede C, Wright WD, Gore SK, Jenkins SS, Freudenthal BD, Todd Washington M, Veaute X, Heyer WD. Srs2 promotes synthesis-dependent strand annealing by disrupting DNA polymerase δ-extending D-loops. eLife 2017; 6. [PMID: 28535142 PMCID: PMC5441872 DOI: 10.7554/elife.22195] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Accepted: 04/29/2017] [Indexed: 01/12/2023] Open
Abstract
Synthesis-dependent strand annealing (SDSA) is the preferred mode of homologous recombination in somatic cells leading to an obligatory non-crossover outcome, thus avoiding the potential for chromosomal rearrangements and loss of heterozygosity. Genetic analysis identified the Srs2 helicase as a prime candidate to promote SDSA. Here, we demonstrate that Srs2 disrupts D-loops in an ATP-dependent fashion and with a distinct polarity. Specifically, we partly reconstitute the SDSA pathway using Rad51, Rad54, RPA, RFC, DNA Polymerase δ with different forms of PCNA. Consistent with genetic data showing the requirement for SUMO and PCNA binding for the SDSA role of Srs2, Srs2 displays a slight but significant preference to disrupt extending D-loops over unextended D-loops when SUMOylated PCNA is present, compared to unmodified PCNA or monoubiquitinated PCNA. Our data establish a biochemical mechanism for the role of Srs2 in crossover suppression by promoting SDSA through disruption of extended D-loops. DOI:http://dx.doi.org/10.7554/eLife.22195.001
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Affiliation(s)
- Jie Liu
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States
| | - Christopher Ede
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States
| | - William D Wright
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States
| | - Steven K Gore
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States
| | - Shirin S Jenkins
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States
| | - Bret D Freudenthal
- Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, United States
| | - M Todd Washington
- Department of Biochemistry, University of Iowa Carver College of Medicine, Iowa City, United States
| | | | - Wolf-Dietrich Heyer
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, United States.,Department of Molecular and Cellular Biology, University of California, Davis, Davis, United States
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30
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Abstract
DNA repair is essential to maintain genomic integrity and initiate genetic diversity. While gene conversion and classical nonhomologous end-joining are the most physiologically predominant forms of DNA repair mechanisms, emerging lines of evidence suggest the usage of several noncanonical homology-directed repair (HDR) pathways in both prokaryotes and eukaryotes in different contexts. Here we review how these alternative HDR pathways are executed, specifically focusing on the determinants that dictate competition between them and their relevance to cancers that display complex genomic rearrangements or maintain their telomeres by homology-directed DNA synthesis.
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31
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Keyamura K, Arai K, Hishida T. Srs2 and Mus81-Mms4 Prevent Accumulation of Toxic Inter-Homolog Recombination Intermediates. PLoS Genet 2016; 12:e1006136. [PMID: 27390022 PMCID: PMC4936719 DOI: 10.1371/journal.pgen.1006136] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 05/31/2016] [Indexed: 11/18/2022] Open
Abstract
Homologous recombination is an evolutionally conserved mechanism that promotes genome stability through the faithful repair of double-strand breaks and single-strand gaps in DNA, and the recovery of stalled or collapsed replication forks. Saccharomyces cerevisiae ATP-dependent DNA helicase Srs2 (a member of the highly conserved UvrD family of helicases) has multiple roles in regulating homologous recombination. A mutation (srs2K41A) resulting in a helicase-dead mutant of Srs2 was found to be lethal in diploid, but not in haploid, cells. In diploid cells, Srs2K41A caused the accumulation of inter-homolog joint molecule intermediates, increased the levels of spontaneous Rad52 foci, and induced gross chromosomal rearrangements. Srs2K41A lethality and accumulation of joint molecules were suppressed by inactivating Rad51 or deleting the Rad51-interaction domain of Srs2, whereas phosphorylation and sumoylation of Srs2 and its interaction with sumoylated proliferating cell nuclear antigen (PCNA) were not required for lethality. The structure-specific complex of crossover junction endonucleases Mus81 and Mms4 was also required for viability of diploid, but not haploid, SRS2 deletion mutants (srs2Δ), and diploid srs2Δ mus81Δ mutants accumulated joint molecule intermediates. Our data suggest that Srs2 and Mus81–Mms4 have critical roles in preventing the formation of (or in resolving) toxic inter-homolog joint molecules, which could otherwise interfere with chromosome segregation and lead to genetic instability. Homologous recombination (HR) is a DNA-repair mechanism that is generally considered error free because it uses an intact sister chromatid as a template. However, in diploid cells, HR can also occur between homologous chromosomes, which can lead to genomic instability through loss of heterozygosity. This alteration is often detected in genetic disorders and cancer, suggesting that tight control of this process is required to ensure genome stability. Yeast Srs2, conserved from bacteria to humans, plays multiple roles in the regulation of HR. We show here that a helicase-dead mutant of Srs2, srs2K41A, is lethal in diploid cells but not in haploid cells. Expression of Srs2K41A in diploid cells causes inter-homolog joint molecule intermediates to accumulate, and leads to gross chromosomal rearrangements. Moreover, srs2Δ mus81Δ double mutants have a severe diploid-specific growth defect with accumulation of inter-homolog joint molecules. These data demonstrate that Srs2 and Mus81-Mms4 participate in essential pathways preventing accumulation of inter-homolog recombination intermediates, thereby reducing the risk of genome instability.
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Affiliation(s)
- Kenji Keyamura
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
| | - Kota Arai
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
| | - Takashi Hishida
- Department of Life Science, Graduate School of Science, Gakushuin University, Tokyo, Japan
- * E-mail:
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32
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Kolesar P, Altmannova V, Silva S, Lisby M, Krejci L. Pro-recombination Role of Srs2 Protein Requires SUMO (Small Ubiquitin-like Modifier) but Is Independent of PCNA (Proliferating Cell Nuclear Antigen) Interaction. J Biol Chem 2016; 291:7594-607. [PMID: 26861880 DOI: 10.1074/jbc.m115.685891] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Indexed: 11/06/2022] Open
Abstract
Srs2 plays many roles in DNA repair, the proper regulation and coordination of which is essential. Post-translational modification by small ubiquitin-like modifier (SUMO) is one such possible mechanism. Here, we investigate the role of SUMO in Srs2 regulation and show that the SUMO-interacting motif (SIM) of Srs2 is important for the interaction with several recombination factors. Lack of SIM, but not proliferating cell nuclear antigen (PCNA)-interacting motif (PIM), leads to increased cell death under circumstances requiring homologous recombination for DNA repair. Simultaneous mutation of SIM in asrs2ΔPIMstrain leads to a decrease in recombination, indicating a pro-recombination role of SUMO. Thus SIM has an ambivalent function in Srs2 regulation; it not only mediates interaction with SUMO-PCNA to promote the anti-recombination function but it also plays a PCNA-independent pro-recombination role, probably by stimulating the formation of recombination complexes. The fact that deletion of PIM suppresses the phenotypes of Srs2 lacking SIM suggests that proper balance between the anti-recombination PCNA-bound and pro-recombination pools of Srs2 is crucial. Notably, sumoylation of Srs2 itself specifically stimulates recombination at the rDNA locus.
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Affiliation(s)
- Peter Kolesar
- From the Department of Biology and National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic
| | | | - Sonia Silva
- the Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark, and
| | - Michael Lisby
- the Department of Biology, University of Copenhagen, Copenhagen 2200, Denmark, and
| | - Lumir Krejci
- From the Department of Biology and National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic, the International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital in Brno, 60200 Brno, Czech Republic
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33
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Aksenova AY, Han G, Shishkin AA, Volkov KV, Mirkin SM. Expansion of Interstitial Telomeric Sequences in Yeast. Cell Rep 2015; 13:1545-51. [PMID: 26586439 DOI: 10.1016/j.celrep.2015.10.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 08/07/2015] [Accepted: 10/08/2015] [Indexed: 11/18/2022] Open
Abstract
Telomeric repeats located within chromosomes are called interstitial telomeric sequences (ITSs). They are polymorphic in length and are likely hotspots for initiation of chromosomal rearrangements that have been linked to human disease. Using our S. cerevisiae system to study repeat-mediated genome instability, we have previously shown that yeast telomeric (Ytel) repeats induce various gross chromosomal rearrangements (GCR) when their G-rich strands serve as the lagging strand template for replication (G orientation). Here, we show that interstitial Ytel repeats in the opposite C orientation prefer to expand rather than cause GCR. A tract of eight Ytel repeats expands at a rate of 4 × 10(-4) per replication, ranking them among the most expansion-prone DNA microsatellites. A candidate-based genetic analysis implicates both post-replication repair and homologous recombination pathways in the expansion process. We propose a model for Ytel repeat expansions and discuss its applications for genome instability and alternative telomere lengthening (ALT).
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Affiliation(s)
- Anna Y Aksenova
- Department of Biology, Tufts University, Medford, MA 02155, USA; Department of Genetics, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Gil Han
- Department of Biology, Tufts University, Medford, MA 02155, USA
| | | | - Kirill V Volkov
- Department of Genetics, St. Petersburg State University, St. Petersburg 199034, Russia
| | - Sergei M Mirkin
- Department of Biology, Tufts University, Medford, MA 02155, USA.
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34
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Kowalczykowski SC. An Overview of the Molecular Mechanisms of Recombinational DNA Repair. Cold Spring Harb Perspect Biol 2015; 7:a016410. [PMID: 26525148 PMCID: PMC4632670 DOI: 10.1101/cshperspect.a016410] [Citation(s) in RCA: 313] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Recombinational DNA repair is a universal aspect of DNA metabolism and is essential for genomic integrity. It is a template-directed process that uses a second chromosomal copy (sister, daughter, or homolog) to ensure proper repair of broken chromosomes. The key steps of recombination are conserved from phage through human, and an overview of those steps is provided in this review. The first step is resection by helicases and nucleases to produce single-stranded DNA (ssDNA) that defines the homologous locus. The ssDNA is a scaffold for assembly of the RecA/RAD51 filament, which promotes the homology search. On finding homology, the nucleoprotein filament catalyzes exchange of DNA strands to form a joint molecule. Recombination is controlled by regulating the fate of both RecA/RAD51 filaments and DNA pairing intermediates. Finally, intermediates that mature into Holliday structures are disjoined by either nucleolytic resolution or topological dissolution.
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Affiliation(s)
- Stephen C Kowalczykowski
- Department of Microbiology & Molecular Genetics and Department of Molecular and Cellular Biology, University of California, Davis, Davis, California 95616
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35
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Abstract
Recombination is a central process to stably maintain and transmit a genome through somatic cell divisions and to new generations. Hence, recombination needs to be coordinated with other events occurring on the DNA template, such as DNA replication, transcription, and the specialized chromosomal functions at centromeres and telomeres. Moreover, regulation with respect to the cell-cycle stage is required as much as spatiotemporal coordination within the nuclear volume. These regulatory mechanisms impinge on the DNA substrate through modifications of the chromatin and directly on recombination proteins through a myriad of posttranslational modifications (PTMs) and additional mechanisms. Although recombination is primarily appreciated to maintain genomic stability, the process also contributes to gross chromosomal arrangements and copy-number changes. Hence, the recombination process itself requires quality control to ensure high fidelity and avoid genomic instability. Evidently, recombination and its regulatory processes have significant impact on human disease, specifically cancer and, possibly, neurodegenerative diseases.
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Affiliation(s)
- Wolf-Dietrich Heyer
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, California 95616-8665 Department of Molecular and Cellular Biology, University of California, Davis, Davis, California 95616-8665
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36
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Audry J, Maestroni L, Delagoutte E, Gauthier T, Nakamura TM, Gachet Y, Saintomé C, Géli V, Coulon S. RPA prevents G-rich structure formation at lagging-strand telomeres to allow maintenance of chromosome ends. EMBO J 2015; 34:1942-58. [PMID: 26041456 DOI: 10.15252/embj.201490773] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Accepted: 05/06/2015] [Indexed: 01/07/2023] Open
Abstract
Replication protein A (RPA) is a highly conserved heterotrimeric single-stranded DNA-binding protein involved in DNA replication, recombination, and repair. In fission yeast, the Rpa1-D223Y mutation provokes telomere shortening. Here, we show that this mutation impairs lagging-strand telomere replication and leads to the accumulation of secondary structures and recruitment of the homologous recombination factor Rad52. The presence of these secondary DNA structures correlates with reduced association of shelterin subunits Pot1 and Ccq1 at telomeres. Strikingly, heterologous expression of the budding yeast Pif1 known to efficiently unwind G-quadruplex rescues all the telomeric defects of the D223Y cells. Furthermore, in vitro data show that the identical D to Y mutation in human RPA specifically affects its ability to bind G-quadruplex. We propose that RPA prevents the formation of G-quadruplex structures at lagging-strand telomeres to promote shelterin association and facilitate telomerase action at telomeres.
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Affiliation(s)
- Julien Audry
- Cancer Research Center of Marseille (CRCM), U1068 Inserm, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University (AMU), Marseille, France Ligue Nationale contre le Cancer (LNCC) (Equipe Labellisée), Paris, France
| | - Laetitia Maestroni
- Cancer Research Center of Marseille (CRCM), U1068 Inserm, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University (AMU), Marseille, France Ligue Nationale contre le Cancer (LNCC) (Equipe Labellisée), Paris, France
| | - Emmanuelle Delagoutte
- Structure des Acides Nucléiques, Télomères et Evolution, Inserm U1154, CNRS UMR 7196, Muséum National d'Histoire Naturelle, Paris Cedex 05, France
| | - Tiphaine Gauthier
- Laboratoire de Biologie Cellulaire et Moléculaire du Controle de la Prolifération UMR5088, Université de Toulouse, Toulouse, France
| | - Toru M Nakamura
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Yannick Gachet
- Laboratoire de Biologie Cellulaire et Moléculaire du Controle de la Prolifération UMR5088, Université de Toulouse, Toulouse, France
| | - Carole Saintomé
- Structure des Acides Nucléiques, Télomères et Evolution, Inserm U1154, CNRS UMR 7196, Muséum National d'Histoire Naturelle, Paris Cedex 05, France UPMC Univ Paris 06, UFR927, Sorbonne Universités, Paris, France
| | - Vincent Géli
- Cancer Research Center of Marseille (CRCM), U1068 Inserm, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University (AMU), Marseille, France Ligue Nationale contre le Cancer (LNCC) (Equipe Labellisée), Paris, France
| | - Stéphane Coulon
- Cancer Research Center of Marseille (CRCM), U1068 Inserm, UMR7258 CNRS, Institut Paoli-Calmettes, Aix Marseille University (AMU), Marseille, France Ligue Nationale contre le Cancer (LNCC) (Equipe Labellisée), Paris, France
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37
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Xu X, Blackwell S, Lin A, Li F, Qin Z, Xiao W. Error-free DNA-damage tolerance in Saccharomyces cerevisiae. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2015; 764:43-50. [DOI: 10.1016/j.mrrev.2015.02.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 01/07/2015] [Accepted: 02/06/2015] [Indexed: 12/18/2022]
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38
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Chavdarova M, Marini V, Sisakova A, Sedlackova H, Vigasova D, Brill SJ, Lisby M, Krejci L. Srs2 promotes Mus81-Mms4-mediated resolution of recombination intermediates. Nucleic Acids Res 2015; 43:3626-42. [PMID: 25765656 PMCID: PMC4402524 DOI: 10.1093/nar/gkv198] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Accepted: 02/26/2015] [Indexed: 11/26/2022] Open
Abstract
A variety of DNA lesions, secondary DNA structures or topological stress within the DNA template may lead to stalling of the replication fork. Recovery of such forks is essential for the maintenance of genomic stability. The structure-specific endonuclease Mus81–Mms4 has been implicated in processing DNA intermediates that arise from collapsed forks and homologous recombination. According to previous genetic studies, the Srs2 helicase may play a role in the repair of double-strand breaks and ssDNA gaps together with Mus81–Mms4. In this study, we show that the Srs2 and Mus81–Mms4 proteins physically interact in vitro and in vivo and we map the interaction domains within the Srs2 and Mus81 proteins. Further, we show that Srs2 plays a dual role in the stimulation of the Mus81–Mms4 nuclease activity on a variety of DNA substrates. First, Srs2 directly stimulates Mus81–Mms4 nuclease activity independent of its helicase activity. Second, Srs2 removes Rad51 from DNA to allow access of Mus81–Mms4 to cleave DNA. Concomitantly, Mus81–Mms4 inhibits the helicase activity of Srs2. Taken together, our data point to a coordinated role of Mus81–Mms4 and Srs2 in processing of recombination as well as replication intermediates.
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Affiliation(s)
- Melita Chavdarova
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5/A4, Brno 625 00, Czech Republic
| | - Victoria Marini
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic
| | - Alexandra Sisakova
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital Brno, Brno, Czech Republic
| | - Hana Sedlackova
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic
| | - Dana Vigasova
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, DK-2200 Copenhagen N, Denmark
| | - Steven J Brill
- Department of Genetics, Cancer Research Institute, Vlarska 7, 833 91 Bratislava, Slovakia
| | - Michael Lisby
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Lumir Krejci
- Department of Biology, Masaryk University, Kamenice 5/A7, Brno 625 00, Czech Republic National Centre for Biomolecular Research, Masaryk University, Kamenice 5/A4, Brno 625 00, Czech Republic International Clinical Research Center, Center for Biomolecular and Cellular Engineering, St. Anne's University Hospital Brno, Brno, Czech Republic
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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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Pietrobon V, Fréon K, Hardy J, Costes A, Iraqui I, Ochsenbein F, Lambert SA. The chromatin assembly factor 1 promotes Rad51-dependent template switches at replication forks by counteracting D-loop disassembly by the RecQ-type helicase Rqh1. PLoS Biol 2014; 12:e1001968. [PMID: 25313826 PMCID: PMC4196752 DOI: 10.1371/journal.pbio.1001968] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 09/04/2014] [Indexed: 11/25/2022] Open
Abstract
A molecular switch for times of replication stress - Chromatin Assembly Factor 1 helps to protect DNA during recombination-mediated template-switching, favoring the rescue of stalled replication forks by both beneficial and detrimental homologous recombination events. At blocked replication forks, homologous recombination mediates the nascent strands to switch template in order to ensure replication restart, but faulty template switches underlie genome rearrangements in cancer cells and genomic disorders. Recombination occurs within DNA packaged into chromatin that must first be relaxed and then restored when recombination is completed. The chromatin assembly factor 1, CAF-1, is a histone H3-H4 chaperone involved in DNA synthesis-coupled chromatin assembly during DNA replication and DNA repair. We reveal a novel chromatin factor-dependent step during replication-coupled DNA repair: Fission yeast CAF-1 promotes Rad51-dependent template switches at replication forks, independently of the postreplication repair pathway. We used a physical assay that allows the analysis of the individual steps of template switch, from the recruitment of recombination factors to the formation of joint molecules, combined with a quantitative measure of the resulting rearrangements. We reveal functional and physical interplays between CAF-1 and the RecQ-helicase Rqh1, the BLM homologue, mutations in which cause Bloom's syndrome, a human disease associating genome instability with cancer predisposition. We establish that CAF-1 promotes template switch by counteracting D-loop disassembly by Rqh1. Consequently, the likelihood of faulty template switches is controlled by antagonistic activities of CAF-1 and Rqh1 in the stability of the D-loop. D-loop stabilization requires the ability of CAF-1 to interact with PCNA and is thus linked to the DNA synthesis step. We propose that CAF-1 plays a regulatory role during template switch by assembling chromatin on the D-loop and thereby impacting the resolution of the D-loop. Obstacles to the progression of DNA replication forks can result in genome rearrangements that are often observed in cancer cells and genomic disorders. Homologous recombination is a mechanism of restarting stalled replication fork that involves synthesis of the new DNA strands switching templates to a second (allelic) copy of the DNA sequence. However, the new strands can also occasionally recombine with nonallelic repeats (distinct regions of the genome that resemble the correct one) and thereby cause the inappropriate fusion of normally distant DNA segments; this is known as faulty template switching. The chromatin assembly factor 1 (CAF-1) is already known to be involved in depositing nucleosomes on DNA during DNA replication and repair. We have found that CAF-1 is also involved in the recombination-mediated template switch pathway in response to replication stress. Using both genetic and physical assays that allow the different steps of template switch to be analyzed, we reveal that CAF-1 protects recombination intermediates from disassembly by the RecQ-type helicase Rqh1, the homologue of BLM (people with mutations that affect BLM have Bloom's syndrome, an inherited predisposition to genome instability and cancer). Consequently, the likelihood of faulty template switch is controlled by the antagonistic activities of CAF-1 and Rqh1. We thus identified an evolutionarily conserved interplay between CAF-1 and RecQ-type helicases that helps to maintain genome stability in the face of replication stress.
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Affiliation(s)
- Violena Pietrobon
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
| | - Karine Fréon
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
| | - Julien Hardy
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
| | - Audrey Costes
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
| | - Ismail Iraqui
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
| | - Françoise Ochsenbein
- Commissariat à l'Energie Atomique, iBiTec-S, Service de Biologie Intégrative et de Génétique Moléculaire, Gif-sur-Yvette, France
| | - Sarah A.E. Lambert
- Institut Curie, Centre de Recherche, Orsay, France
- Centre national de la Recherche Scientifique, UMR3348, Centre Universitaire, Orsay, France
- * E-mail:
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Tsutsui Y, Kurokawa Y, Ito K, Siddique MSP, Kawano Y, Yamao F, Iwasaki H. Multiple regulation of Rad51-mediated homologous recombination by fission yeast Fbh1. PLoS Genet 2014; 10:e1004542. [PMID: 25165823 PMCID: PMC4148199 DOI: 10.1371/journal.pgen.1004542] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 06/16/2014] [Indexed: 11/18/2022] Open
Abstract
Fbh1, an F-box helicase related to bacterial UvrD, has been proposed to modulate homologous recombination in fission yeast. We provide several lines of evidence for such modulation. Fbh1, but not the related helicases Srs2 and Rqh1, suppressed the formation of crossover recombinants from single HO-induced DNA double-strand breaks. Purified Fbh1 in complex with Skp1 (Fbh1-Skp1 complex) inhibited Rad51-driven DNA strand exchange by disrupting Rad51 nucleoprotein filaments in an ATP-dependent manner; this disruption was alleviated by the Swi5-Sfr1 complex, an auxiliary activator of Rad51. In addition, the reconstituted SCFFbh1 complex, composed of purified Fbh1-Skp1 and Pcu1-Rbx1, displayed ubiquitin-ligase E3 activity toward Rad51. Furthermore, Fbh1 reduced the protein level of Rad51 in stationary phase in an F-box-dependent, but not in a helicase domain-independent manner. These results suggest that Fbh1 negatively regulates Rad51-mediated homologous recombination via its two putative, unrelated activities, namely DNA unwinding/translocation and ubiquitin ligation. In addition to its anti-recombinase activity, we tentatively suggest that Fbh1 might also have a pro-recombination role in vivo, because the Fbh1-Skp1 complex stimulated Rad51-mediated strand exchange in vitro after strand exchange had been initiated. Homologous recombination is required for repairing DNA double-strand breaks (DSBs), which are induced by exogenous factors such as DNA damaging agents or by endogenous factors such as collapse of DNA replication fork in mitotic cells. If improperly processed, DSBs could lead to chromosome rearrangement, cell death, or tumorigenesis in mammals, and thus HR is strictly controlled at several steps, including Rad51 recombinase-driven DNA strand exchange reaction. Specifically, DNA helicases have been shown to be important for suppression of inappropriate recombination events. In this study, we analyzed one such DNA helicase, fission yeast Fbh1. We used an in vivo single-DSB repair assay to show that Fbh1 suppresses crossover formation between homologous chromosomes. Next, we obtained in vitro evidence that Fbh1 acts as an inhibitor of the strand-exchange reaction in the absence of Swi5-Sfr1, but stimulates the reaction after it starts. Furthermore, we found that SCFFbh1 has ubiquitin-ligase activity toward Rad51 in vitro and that Fbh1 regulates the protein level of Rad51 in the stationary phase. These results suggest Fbh1 regulates Rad51-mediated homologous recombination by its seemingly-unrelated two activities, DNA helicase/translocase and ubiquitin ligase.
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Affiliation(s)
- Yasuhiro Tsutsui
- Department of Biological Sciences, School and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
- * E-mail: (YT); (HI)
| | - Yumiko Kurokawa
- Education Academy of Computational Life Science, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Kentaro Ito
- Department of Biological Sciences, School and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Md. Shahjahan P. Siddique
- Department of Biological Sciences, School and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Yumiko Kawano
- Department of Biological Sciences, School and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
| | - Fumiaki Yamao
- International Institute for Advanced Studies, Kizugawa, Kyoto, Japan
| | - Hiroshi Iwasaki
- Department of Biological Sciences, School and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Meguro-ku, Tokyo, Japan
- * E-mail: (YT); (HI)
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42
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Signon L, Simon MN. The analysis of S. cerevisiae cells deleted for mitotic cyclin Clb2 reveals a novel requirement of Sgs1 DNA helicase and Exonuclease 1 when replication forks break in the presence of alkylation damage. Mutat Res 2014; 769:80-92. [PMID: 25771727 DOI: 10.1016/j.mrfmmm.2014.07.008] [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: 10/14/2013] [Revised: 07/19/2014] [Accepted: 07/22/2014] [Indexed: 10/25/2022]
Abstract
In this study, we report the effects of deleting the principal mitotic cyclin, Clb2, in different repair deficient contexts on sensitivity to the alkylating DNA damaging agent, methyl methanesulphonate (MMS). A yeast clb2 mutant is sensitive to MMS and displays synergistic effect when combined with inactivation of numerous genes involved in DNA recombination and replication. In contrast, clb2 has basically no additional effect with deletion of the RecQ helicase SGS1, the exonuclease EXO1 and the protein kinase RAD53 suggesting that Clb2 functions in these pathways. In addition, clb2 increases the viability of the mec1 kinase deficient mutant, suggesting Mec1 inhibits a deleterious Clb2 activity. Interestingly, we found that the rescue by EXO1 deletion of rad53K227 mutant, deficient in checkpoint activation, requires Sgs1, suggesting a role for Rad53, independent of its checkpoint function, in regulating an ordered recruitment of Sgs1 and Exo1 to fork structure. Overall, our data suggest that Clb2 affects recombinant structure of replication fork blocked by alkylating DNA damage at numerous steps and could regulate Sgs1 and Exo1 activity. In addition, we found novel requirement of Sgs1 DNA helicase and Exonuclease 1 when replication forks breaks in the presence of alkylation damage. Models for the functional interactions of mitotic cyclin Clb2, Sgs1 and Exo1 with replication fork stabilization are proposed.
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Affiliation(s)
- Laurence Signon
- Laboratoire d'Ingenierie des Systèmes Macromoléculaires CNRS UPR9027, Aix-Marseille University, 13402 Marseille Cedex 20, France; Université Paris-Sud, CNRS UMR8621, Institut de Génétique et Microbiologie, Bâtiment 400, 91405 Orsay Cedex, France.
| | - Marie Noelle Simon
- Laboratoire d'Ingenierie des Systèmes Macromoléculaires CNRS UPR9027, Aix-Marseille University, 13402 Marseille Cedex 20, France
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43
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Jung H, Lee JA, Choi S, Lee H, Ahn B. Characterization of the Caenorhabditis elegans HIM-6/BLM helicase: unwinding recombination intermediates. PLoS One 2014; 9:e102402. [PMID: 25036527 PMCID: PMC4103807 DOI: 10.1371/journal.pone.0102402] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 06/12/2014] [Indexed: 02/02/2023] Open
Abstract
Mutations in three human RecQ genes are implicated in heritable human syndromes. Mutations in BLM, a RecQ gene, cause Bloom syndrome (BS), which is characterized by short stature, cancer predisposition, and sensitivity to sunlight. BLM is a RecQ DNA helicase that, with interacting proteins, is able to dissolve various DNA structures including double Holliday junctions. A BLM ortholog, him-6, has been identified in Caenorhabditis elegans, but little is known about its enzymatic activities or its in vivo roles. By purifying recombinant HIM-6 and performing biochemical assays, we determined that the HIM-6 has DNA-dependent ATPase activity HIM-6 and helicase activity that proceeds in the 3'-5' direction and needs at least five 3' overhanging nucleotides. HIM-6 is also able to unwind DNA structures including D-loops and Holliday junctions. Worms with him-6 mutations were defective in recovering the cell cycle arrest after HU treatment. These activities strongly support in vivo roles for HIM-6 in processing recombination intermediates.
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Affiliation(s)
- Hana Jung
- Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea
| | - Jin A Lee
- Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea
| | - Seoyoon Choi
- Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea
| | - Hyunwoo Lee
- Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea
| | - Byungchan Ahn
- Department of Life Sciences, University of Ulsan, Ulsan, Republic of Korea
- * E-mail:
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44
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Sommers JA, Banerjee T, Hinds T, Wan B, Wold MS, Lei M, Brosh RM. Novel function of the Fanconi anemia group J or RECQ1 helicase to disrupt protein-DNA complexes in a replication protein A-stimulated manner. J Biol Chem 2014; 289:19928-41. [PMID: 24895130 DOI: 10.1074/jbc.m113.542456] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Understanding how cellular machinery deals with chromosomal genome complexity is an important question because protein bound to DNA may affect various cellular processes of nucleic acid metabolism. DNA helicases are at the forefront of such processes, yet there is only limited knowledge how they remodel protein-DNA complexes and how these mechanisms are regulated. We have determined that representative human RecQ and Fe-S cluster DNA helicases are potently blocked by a protein-DNA interaction. The Fanconi anemia group J (FANCJ) helicase partners with the single-stranded DNA-binding protein replication protein A (RPA) to displace BamHI-E111A bound to duplex DNA in a specific manner. Protein displacement was dependent on the ATPase-driven function of the helicase and unique properties of RPA. Further biochemical studies demonstrated that the shelterin proteins TRF1 and TRF2, which preferentially bind the telomeric repeat found at chromosome ends, effectively block FANCJ from unwinding the forked duplex telomeric substrate. RPA, but not the Escherichia coli single-stranded DNA-binding protein or shelterin factor Pot1, stimulated FANCJ ejection of TRF1 from the telomeric DNA substrate. FANCJ was also able to displace TRF2 from the telomeric substrate in an RPA-dependent manner. The stimulation of helicase-catalyzed protein displacement is also observed with the DNA helicase RECQ1, suggesting a conserved functional interaction of RPA-interacting helicases. These findings suggest that partnerships between RPA and interacting human DNA helicases may greatly enhance their ability to dislodge proteins bound to duplex DNA, an activity that is likely to be highly relevant to their biological roles in DNA metabolism.
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Affiliation(s)
- Joshua A Sommers
- From the Laboratory of Molecular Gerontology, Biomedical Research Center, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Taraswi Banerjee
- From the Laboratory of Molecular Gerontology, Biomedical Research Center, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Twila Hinds
- From the Laboratory of Molecular Gerontology, Biomedical Research Center, NIA, National Institutes of Health, Baltimore, Maryland 21224
| | - Bingbing Wan
- the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, and
| | - Marc S Wold
- the Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242
| | - Ming Lei
- the Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109, and
| | - Robert M Brosh
- From the Laboratory of Molecular Gerontology, Biomedical Research Center, NIA, National Institutes of Health, Baltimore, Maryland 21224,
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45
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Lytle AK, Origanti SS, Qiu Y, VonGermeten J, Myong S, Antony E. Context-Dependent Remodeling of Rad51–DNA Complexes by Srs2 Is Mediated by a Specific Protein–Protein Interaction. J Mol Biol 2014; 426:1883-97. [DOI: 10.1016/j.jmb.2014.02.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 02/10/2014] [Accepted: 02/16/2014] [Indexed: 10/25/2022]
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46
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Qiu Y, Antony E, Doganay S, Koh HR, Lohman TM, Myong S. Srs2 prevents Rad51 filament formation by repetitive motion on DNA. Nat Commun 2014; 4:2281. [PMID: 23939144 DOI: 10.1038/ncomms3281] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 07/09/2013] [Indexed: 11/09/2022] Open
Abstract
Srs2 dismantles presynaptic Rad51 filaments and prevents its re-formation as an anti-recombinase. However, the molecular mechanism by which Srs2 accomplishes these tasks remains unclear. Here we report a single-molecule fluorescence study of the dynamics of Rad51 filament formation and its disruption by Srs2. Rad51 forms filaments on single-stranded DNA by sequential binding of primarily monomers and dimers in a 5'-3' direction. One Rad51 molecule binds to three nucleotides, and six monomers are required to achieve a stable nucleation cluster. Srs2 exhibits ATP-dependent repetitive motion on single-stranded DNA and this activity prevents re-formation of the Rad51 filament. The same activity of Srs2 cannot prevent RecA filament formation, indicating its specificity for Rad51. Srs2's DNA-unwinding activity is greatly suppressed when Rad51 filaments form on duplex DNA. Taken together, our results reveal an exquisite and highly specific mechanism by which Srs2 regulates the Rad51 filament formation.
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Affiliation(s)
- Yupeng Qiu
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
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47
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Paliwal S, Kanagaraj R, Sturzenegger A, Burdova K, Janscak P. Human RECQ5 helicase promotes repair of DNA double-strand breaks by synthesis-dependent strand annealing. Nucleic Acids Res 2013; 42:2380-90. [PMID: 24319145 PMCID: PMC3936725 DOI: 10.1093/nar/gkt1263] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Most mitotic homologous recombination (HR) events proceed via a synthesis-dependent strand annealing mechanism to avoid crossing over, which may give rise to chromosomal rearrangements and loss of heterozygosity. The molecular mechanisms controlling HR sub-pathway choice are poorly understood. Here, we show that human RECQ5, a DNA helicase that can disrupt RAD51 nucleoprotein filaments, promotes formation of non-crossover products during DNA double-strand break-induced HR and counteracts the inhibitory effect of RAD51 on RAD52-mediated DNA annealing in vitro and in vivo. Moreover, we demonstrate that RECQ5 deficiency is associated with an increased occupancy of RAD51 at a double-strand break site, and it also causes an elevation of sister chromatid exchanges on inactivation of the Holliday junction dissolution pathway or on induction of a high load of DNA damage in the cell. Collectively, our findings suggest that RECQ5 acts during the post-synaptic phase of synthesis-dependent strand annealing to prevent formation of aberrant RAD51 filaments on the extended invading strand, thus limiting its channeling into potentially hazardous crossover pathway of HR.
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Affiliation(s)
- Shreya Paliwal
- Institute of Molecular Cancer Research, University of Zurich, CH-8057 Zurich, Switzerland and Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 14300 Prague, Czech Republic
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Esta A, Ma E, Dupaigne P, Maloisel L, Guerois R, Le Cam E, Veaute X, Coïc E. Rad52 sumoylation prevents the toxicity of unproductive Rad51 filaments independently of the anti-recombinase Srs2. PLoS Genet 2013; 9:e1003833. [PMID: 24130504 PMCID: PMC3794917 DOI: 10.1371/journal.pgen.1003833] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 08/12/2013] [Indexed: 11/18/2022] Open
Abstract
The budding yeast Srs2 is the archetype of helicases that regulate several aspects of homologous recombination (HR) to maintain genomic stability. Srs2 inhibits HR at replication forks and prevents high frequencies of crossing-over. Additionally, sensitivity to DNA damage and synthetic lethality with replication and recombination mutants are phenotypes that can only be attributed to another role of Srs2: the elimination of lethal intermediates formed by recombination proteins. To shed light on these intermediates, we searched for mutations that bypass the requirement of Srs2 in DNA repair without affecting HR. Remarkably, we isolated rad52-L264P, a novel allele of RAD52, a gene that encodes one of the most central recombination proteins in yeast. This mutation suppresses a broad spectrum of srs2Δ phenotypes in haploid cells, such as UV and γ-ray sensitivities as well as synthetic lethality with replication and recombination mutants, while it does not significantly affect Rad52 functions in HR and DNA repair. Extensive analysis of the genetic interactions between rad52-L264P and srs2Δ shows that rad52-L264P bypasses the requirement for Srs2 specifically for the prevention of toxic Rad51 filaments. Conversely, this Rad52 mutant cannot restore viability of srs2Δ cells that accumulate intertwined recombination intermediates which are normally processed by Srs2 post-synaptic functions. The avoidance of toxic Rad51 filaments by Rad52-L264P can be explained by a modification of its Rad51 filament mediator activity, as indicated by Chromatin immunoprecipitation and biochemical analysis. Remarkably, sensitivity to DNA damage of srs2Δ cells can also be overcome by stimulating Rad52 sumoylation through overexpression of the sumo-ligase SIZ2, or by replacing Rad52 by a Rad52-SUMO fusion protein. We propose that, like the rad52-L264P mutation, sumoylation modifies Rad52 activity thereby changing the properties of Rad51 filaments. This conclusion is strengthened by the finding that Rad52 is often associated with complete Rad51 filaments in vitro. Homologous recombination (HR) is essential for double-strand break repair and participates in post-replication restart of stalled and collapsed replication forks. However, HR can lead to genome rearrangements and has to be strictly controlled. The budding yeast Srs2 is involved in the prevention of high crossing-over frequencies and in the inhibition of HR at replication forks. Nevertheless, important phenotypes of srs2Δ mutants, like sensitivity to DNA damage and synthetic lethality with replication and recombination mutants, can only be attributed to another role of Srs2: the elimination of lethal intermediates formed by recombination proteins. The nature of these intermediates remains to be defined. In a screen designed to uncover mutations able to suppress srs2Δ phenotypes, we isolated a novel allele of Rad52 (rad52-L264P), the gene that codes for the major Rad51 nucleoprotein filament mediator. Interestingly, we observed that rad52-L264P bypasses the requirement for Srs2 without affecting DNA repair by HR. We also found that Rad52-L264P specifically prevents the formation of unproductive Rad51 filaments before strand invasion, allowing us to define Srs2 substrates. Further analysis showed that Rad52-L264P mimics the properties of the Rad52-SUMO conjugate, revealing that Rad52 assembles Rad51 filaments differently according to its sumoylation status.
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Affiliation(s)
- Aline Esta
- CEA, DSV, iRCM, SIGRR, LRGM, Fontenay-aux-Roses, France
| | - Emilie Ma
- CEA, DSV, iRCM, SIGRR, LRGM, Fontenay-aux-Roses, France
| | - Pauline Dupaigne
- Laboratoire de Microscopie Moléculaire et Cellulaire, UMR 8126, Interactions Moléculaires et Cancer, CNRS–Université Paris Sud–Institut de Cancérologie Gustave Roussy, Villejuif, France
| | | | | | - Eric Le Cam
- Laboratoire de Microscopie Moléculaire et Cellulaire, UMR 8126, Interactions Moléculaires et Cancer, CNRS–Université Paris Sud–Institut de Cancérologie Gustave Roussy, Villejuif, France
| | - Xavier Veaute
- CEA, DSV, iRCM, SIGRR, LRGM, Fontenay-aux-Roses, France
| | - Eric Coïc
- CEA, DSV, iRCM, SIGRR, LRGM, Fontenay-aux-Roses, France
- * E-mail:
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49
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Putative antirecombinase Srs2 DNA helicase promotes noncrossover homologous recombination avoiding loss of heterozygosity. Proc Natl Acad Sci U S A 2013; 110:16067-72. [PMID: 24043837 DOI: 10.1073/pnas.1303111110] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
DNA damage alone or DNA replication fork arrest at damaged sites may induce DNA double-strand breaks and initiate homologous recombination. This event can result in a crossover with a homologous chromosome, causing loss of heterozygosity along the chromosome. It is known that Srs2 acts as an antirecombinase at the replication fork: it is recruited by the SUMO (a small ubiquitin-related modifier)-conjugated DNA-polymerase sliding clamp (PCNA) and interferes with Rad51/Rad52-mediated homologous recombination. Here, we report that Srs2 promotes another type of homologous recombination that produces noncrossover products only, in collaboration with PCNA and Rad51. Srs2 proteins lacking the Rad51-binding domain, PCNA-SUMO-binding motifs, or ATP hydrolysis-dependent DNA helicase activity reduce this noncrossover recombination. However, the removal of either the Rad51-binding domain or the PCNA-binding motif strongly increases crossovers. Srs2 gene mutations are epistatic to mutations in the PCNA modification-related genes encoding PCNA, Siz1 (a SUMO ligase) and Rad6 (a ubiquitin-conjugating protein). Knocking out RAD51 blocked this recombination but enhanced nonhomologous end-joining. We hypothesize that, during DNA double-strand break repair, Srs2 mediates collaboration between the Rad51 nucleofilament and PCNA-SUMO and directs the heteroduplex intermediate to DNA synthesis in a moving bubble. This Rad51/Rad52/Srs2/PCNA-mediated noncrossover pathway avoids both interchromosomal crossover and imprecise end-joining, two potential paths leading to loss of heterozygosity, and contributes to genome maintenance and human health.
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50
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Dziadkowiec D, Kramarz K, Kanik K, Wisniewski P, Carr AM. Involvement of Schizosaccharomyces pombe rrp1+ and rrp2+ in the Srs2- and Swi5/Sfr1-dependent pathway in response to DNA damage and replication inhibition. Nucleic Acids Res 2013; 41:8196-209. [PMID: 23828040 PMCID: PMC3783160 DOI: 10.1093/nar/gkt564] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Previously we identified Rrp1 and Rrp2 as two proteins required for the Sfr1/Swi5-dependent branch of homologous recombination (HR) in Schizosaccharomyces pombe. Here we use a yeast two-hybrid approach to demonstrate that Rrp1 and Rrp2 can interact with each other and with Swi5, an HR mediator protein. Rrp1 and Rrp2 form co-localizing methyl methanesulphonate-induced foci in nuclei, further suggesting they function as a complex. To place the Rrp1/2 proteins more accurately within HR sub-pathways, we carried out extensive epistasis analysis between mutants defining Rrp1/2, Rad51 (recombinase), Swi5 and Rad57 (HR-mediators) plus the anti-recombinogenic helicases Srs2 and Rqh1. We confirm that Rrp1 and Rrp2 act together with Srs2 and Swi5 and independently of Rad57 and show that Rqh1 also acts independently of Rrp1/2. Mutants devoid of Srs2 are characterized by elevated recombination frequency with a concomitant increase in the percentage of conversion-type recombinants. Strains devoid of Rrp1 or Rrp2 did not show a change in HR frequency, but the number of conversion-type recombinants was increased, suggesting a possible function for Rrp1/2 with Srs2 in counteracting Rad51 activity. Our data allow us to propose a model placing Rrp1 and Rrp2 functioning together with Swi5 and Srs2 in a synthesis-dependent strand annealing HR repair pathway.
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Affiliation(s)
- Dorota Dziadkowiec
- Faculty of Biotechnology, Wrocław University, Przybyszewskiego 63-77, 51-148 Wrocław, Poland, Institute of Low Temperature and Structure Research, Polish Academy of Sciences, PO Box 1410, 50-950 Wrocław, Poland and Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, BN1 9RQ, UK
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