1
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Carver A, Yu TY, Yates LA, White T, Wang R, Lister K, Jasin M, Zhang X. Molecular basis of FIGNL1 in dissociating RAD51 from DNA and chromatin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.16.603765. [PMID: 39071279 PMCID: PMC11275795 DOI: 10.1101/2024.07.16.603765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Maintaining genome integrity is an essential and challenging process. RAD51 recombinase, the central player of several crucial processes in repairing and protecting genome integrity, forms filaments on DNA. RAD51 filaments are tightly regulated. One of these regulators is FIGNL1, that prevents persistent RAD51 foci post-damage and genotoxic chromatin association in cells. The cryogenic electron microscopy structure of FIGNL1 in complex with RAD51 reveals that the FIGNL1 forms a non-planar hexamer and RAD51 N-terminus is enclosed in the FIGNL1 hexamer pore. Mutations in pore loop or catalytic residues of FIGNL1 render it defective in filament disassembly and are lethal in mouse embryonic stem cells. Our study reveals a unique mechanism for removing RAD51 from DNA and provides the molecular basis for FIGNL1 in maintaining genome stability.
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Affiliation(s)
- Alexander Carver
- DNA Processing Machines Laboratory, Francis Crick Institute, London, UK
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, UK
- These authors contributed equally to this study
| | - Tai-Yuan Yu
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center
- These authors contributed equally to this study
| | - Luke A Yates
- DNA Processing Machines Laboratory, Francis Crick Institute, London, UK
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, UK
| | - Travis White
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center
| | - Raymond Wang
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center
| | - Katie Lister
- DNA Processing Machines Laboratory, Francis Crick Institute, London, UK
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, UK
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center
| | - Xiaodong Zhang
- DNA Processing Machines Laboratory, Francis Crick Institute, London, UK
- Section of Structural and Synthetic Biology, Department of Infectious Disease, Imperial College London, London, UK
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2
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Pale LM, Khatib JB, Nicolae CM, Moldovan GL. CRISPR knockout genome-wide screens identify the HELQ-RAD52 axis in regulating the repair of cisplatin-induced single stranded DNA gaps. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.17.589988. [PMID: 38659927 PMCID: PMC11042333 DOI: 10.1101/2024.04.17.589988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Treatment with genotoxic agents, such as platinum compounds, is still the mainstay therapeutical approach for the majority of cancers. Our understanding of the mechanisms of action of these drugs is however imperfect, and continuously evolving. Recent advances in the field highlighted single stranded DNA (ssDNA) gap accumulation as a potential determinant underlying cisplatin chemosensitivity, at least in some genetic backgrounds, such as BRCA mutations. Cisplatin-induced ssDNA gaps form upon the arrest of replication forks at sites of cisplatin adducts, and restart of DNA synthesis downstream of the lesion through repriming catalyzed by the PRIMPOL enzyme. Here, we show that PRIMPOL overexpression in otherwise wildtype cells results in accumulation of cisplatin-induced ssDNA gaps without sensitizing cells to cisplatin, suggesting that ssDNA gap accumulation does not confer cisplatin sensitivity in BRCA-proficient cells. To understand how ssDNA gaps may cause cellular sensitivity, we employed CRISPR-mediated genome-wide genetic screening to identify factors which enable the cytotoxicity of cisplatin-induced ssDNA gaps. We found that the helicase HELQ specifically suppresses cisplatin sensitivity in PRIMPOL-overexpressing cells, and this is associated with reduced ssDNA accumulation. We moreover identify RAD52 as a mediator of this pathway, and show that RAD52 promotes ssDNA gap accumulation through a BRCA-mediated mechanism. Our work identified the HELQ-RAD52-BRCA axis as a regulator of ssDNA gap processing, shedding light on the mechanisms of cisplatin sensitization in cancer therapy.
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Affiliation(s)
- Lindsey M. Pale
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Jude B. Khatib
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - Claudia M. Nicolae
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| | - George-Lucian Moldovan
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
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3
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Bakhshalizadeh S, Bird AD, Sreenivasan R, Bell KM, Robevska G, van den Bergen J, Asghari-Jafarabadi M, Kueh AJ, Touraine P, Lokchine A, Jaillard S, Ayers KL, Wilhelm D, Sinclair AH, Tucker EJ. A Human Homozygous HELQ Missense Variant Does Not Cause Premature Ovarian Insufficiency in a Mouse Model. Genes (Basel) 2024; 15:333. [PMID: 38540391 PMCID: PMC10970702 DOI: 10.3390/genes15030333] [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: 02/01/2024] [Revised: 02/26/2024] [Accepted: 02/29/2024] [Indexed: 04/02/2024] Open
Abstract
Disruption of meiosis and DNA repair genes is associated with female fertility disorders like premature ovarian insufficiency (POI). In this study, we identified a homozygous missense variant in the HELQ gene (c.596 A>C; p.Gln199Pro) through whole exome sequencing in a POI patient, a condition associated with disrupted ovarian function and female infertility. HELQ, an enzyme involved in DNA repair, plays a crucial role in repairing DNA cross-links and has been linked to germ cell maintenance, fertility, and tumour suppression in mice. To explore the potential association of the HELQ variant with POI, we used CRISPR/Cas9 to create a knock-in mouse model harbouring the equivalent of the human HELQ variant identified in the POI patient. Surprisingly, Helq knock-in mice showed no discernible phenotype, with fertility levels, histological features, and follicle development similar to wild-type mice. Despite the lack of observable effects in mice, the potential role of HELQ in human fertility, especially in the context of POI, should not be dismissed. Larger studies encompassing diverse ethnic populations and alternative functional approaches will be necessary to further examine the role of HELQ in POI. Our results underscore the potential uncertainties associated with genomic variants and the limitations of in vivo animal modelling.
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Affiliation(s)
- Shabnam Bakhshalizadeh
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
- Department of Paediatrics, The University of Melbourne, Melbourne, VIC 3052, Australia
| | - Anthony D. Bird
- Department of Anatomy & Physiology, The University of Melbourne, Parkville, VIC 3010, Australia; (A.D.B.); (D.W.)
- Hudson Institute of Medical Research, Monash Medical Centre, Melbourne, VIC 3168, Australia
- Department of Molecular & Translational Science, Monash University, Melbourne, VIC 3168, Australia
| | - Rajini Sreenivasan
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
| | - Katrina M. Bell
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
| | - Gorjana Robevska
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
| | - Jocelyn van den Bergen
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
| | - Mohammad Asghari-Jafarabadi
- Biostatistics Unit, School of Public Health and Preventative Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC 3004, Australia;
- Department of Psychiatry, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, VIC 3168, Australia
| | - Andrew J. Kueh
- The Walter and Eliza Hall Institute, Parkville, VIC 3052, Australia;
- Department of Medical Biology, University of Melbourne, Parkville, VIC 3052, Australia
| | - Philippe Touraine
- Department of Endocrinology and Reproductive Medicine, Pitie Salpetriere Hospital, AP-HP, Sorbonne University Medicine, 75013 Paris, France;
| | - Anna Lokchine
- IRSET (Institut de Recherche en Santé, Environnement et Travail), INSERM/EHESP/Univ Rennes/CHU Rennes–UMR_S 1085, 35000 Rennes, France; (A.L.); (S.J.)
- CHU Rennes, Service de Cytogénétique et Biologie Cellulaire, 35033 Rennes, France
| | - Sylvie Jaillard
- IRSET (Institut de Recherche en Santé, Environnement et Travail), INSERM/EHESP/Univ Rennes/CHU Rennes–UMR_S 1085, 35000 Rennes, France; (A.L.); (S.J.)
- CHU Rennes, Service de Cytogénétique et Biologie Cellulaire, 35033 Rennes, France
| | - Katie L. Ayers
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
- Department of Paediatrics, The University of Melbourne, Melbourne, VIC 3052, Australia
| | - Dagmar Wilhelm
- Department of Anatomy & Physiology, The University of Melbourne, Parkville, VIC 3010, Australia; (A.D.B.); (D.W.)
| | - Andrew H. Sinclair
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
- Department of Paediatrics, The University of Melbourne, Melbourne, VIC 3052, Australia
| | - Elena J. Tucker
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia; (S.B.); (R.S.); (K.M.B.); (G.R.); (J.v.d.B.); (K.L.A.); (A.H.S.)
- Department of Paediatrics, The University of Melbourne, Melbourne, VIC 3052, Australia
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4
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Kumar N, Taneja A, Ghosh M, Rothweiler U, Sundaresan N, Singh M. Harmonin homology domain-mediated interaction of RTEL1 helicase with RPA and DNA provides insights into its recruitment to DNA repair sites. Nucleic Acids Res 2024; 52:1450-1470. [PMID: 38153196 PMCID: PMC10853778 DOI: 10.1093/nar/gkad1208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/04/2023] [Accepted: 12/06/2023] [Indexed: 12/29/2023] Open
Abstract
The regulator of telomere elongation helicase 1 (RTEL1) plays roles in telomere DNA maintenance, DNA repair, and genome stability by dismantling D-loops and unwinding G-quadruplex structures. RTEL1 comprises a helicase domain, two tandem harmonin homology domains 1&2 (HHD1 and HHD2), and a Zn2+-binding RING domain. In vitro D-loop disassembly by RTEL1 is enhanced in the presence of replication protein A (RPA). However, the mechanism of RTEL1 recruitment at non-telomeric D-loops remains unknown. In this study, we have unravelled a direct physical interaction between RTEL1 and RPA. Under DNA damage conditions, we showed that RTEL1 and RPA colocalise in the cell. Coimmunoprecipitation showed that RTEL1 and RPA interact, and the deletion of HHDs of RTEL1 significantly reduced this interaction. NMR chemical shift perturbations (CSPs) showed that RPA uses its 32C domain to interact with the HHD2 of RTEL1. Interestingly, HHD2 also interacted with DNA in the in vitro experiments. HHD2 structure was determined using X-ray crystallography, and NMR CSPs mapping revealed that both RPA 32C and DNA competitively bind to HHD2 on an overlapping surface. These results establish novel roles of accessory HHDs in RTEL1's functions and provide mechanistic insights into the RPA-mediated recruitment of RTEL1 to DNA repair sites.
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Affiliation(s)
- Niranjan Kumar
- Molecular Biophysics Unit, Indian Institute of Science, Bengaluru 560012, India
| | - Arushi Taneja
- Department of Microbiology and Cell Biology, Indian Institute of Science, Bengaluru 560012, India
| | - Meenakshi Ghosh
- Molecular Biophysics Unit, Indian Institute of Science, Bengaluru 560012, India
| | - Ulli Rothweiler
- The Norwegian Structural Biology Centre, Department of Chemistry, The Arctic University of Norway, N-9037, Tromsø, Norway
| | | | - Mahavir Singh
- Molecular Biophysics Unit, Indian Institute of Science, Bengaluru 560012, India
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5
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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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6
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Tang N, Wen W, Liu Z, Xiong X, Wu Y. HELQ as a DNA helicase: Its novel role in normal cell function and tumorigenesis (Review). Oncol Rep 2023; 50:220. [PMID: 37921071 PMCID: PMC10652244 DOI: 10.3892/or.2023.8657] [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: 02/22/2023] [Accepted: 08/08/2023] [Indexed: 11/04/2023] Open
Abstract
Helicase POLQ‑like (HELQ or Hel308), is a highly conserved, 3'‑5' superfamily II DNA helicase that contributes to diverse DNA processes, including DNA repair, unwinding, and strand annealing. HELQ deficiency leads to subfertility, due to its critical role in germ cell stability. In addition, the abnormal expression of HELQ has been observed in multiple tumors and a number of molecular pathways, including the nucleotide excision repair, checkpoint kinase 1‑DNA repair protein RAD51 homolog 1 and ATM/ATR pathways, have been shown to be involved in HELQ. In the present review, the structure and characteristics of HELQ, as well as its major functions in DNA processing, were described. Molecular mechanisms involving HELQ in the context of tumorigenesis were also described. It was deduced that HELQ biology warrants investigation, and that its critical roles in the regulation of various DNA processes and participation in tumorigenesis are clinically relevant.
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Affiliation(s)
- Nan Tang
- Department of Traditional Chinese Medicine, Guangzhou Red Cross Hospital of Jinan University, Guangzhou, Guangdong 510220, P.R. China
| | - Weilun Wen
- Department of Traditional Chinese Medicine, Guangzhou Red Cross Hospital of Jinan University, Guangzhou, Guangdong 510220, P.R. China
| | - Zhihe Liu
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital of Jinan University, Guangzhou, Guangdong 510220, P.R. China
| | - Xifeng Xiong
- Guangzhou Institute of Traumatic Surgery, Guangzhou Red Cross Hospital of Jinan University, Guangzhou, Guangdong 510220, P.R. China
| | - Yanhua Wu
- Department of Traditional Chinese Medicine, Guangzhou Red Cross Hospital of Jinan University, Guangzhou, Guangdong 510220, P.R. China
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7
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Appleby R, Bollschweiler D, Chirgadze DY, Joudeh L, Pellegrini L. A metal ion-dependent mechanism of RAD51 nucleoprotein filament disassembly. iScience 2023; 26:106689. [PMID: 37216117 PMCID: PMC10192527 DOI: 10.1016/j.isci.2023.106689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/21/2023] [Accepted: 04/13/2023] [Indexed: 05/24/2023] Open
Abstract
The RAD51 ATPase polymerizes on single-stranded DNA to form nucleoprotein filaments (NPFs) that are critical intermediates in the reaction of homologous recombination. ATP binding maintains the NPF in a competent conformation for strand pairing and exchange. Once strand exchange is completed, ATP hydrolysis licenses the filament for disassembly. Here we show that the ATP-binding site of the RAD51 NPF contains a second metal ion. In the presence of ATP, the metal ion promotes the local folding of RAD51 into the conformation required for DNA binding. The metal ion is absent in the ADP-bound RAD51 filament, that rearranges in a conformation incompatible with DNA binding. The presence of the second metal ion explains how RAD51 couples the nucleotide state of the filament to DNA binding. We propose that loss of the second metal ion upon ATP hydrolysis drives RAD51 dissociation from the DNA and weakens filament stability, contributing to NPF disassembly.
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Affiliation(s)
- Robert Appleby
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
| | | | | | - Luay Joudeh
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
| | - Luca Pellegrini
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1GA, UK
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8
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Emmenecker C, Mézard C, Kumar R. Repair of DNA double-strand breaks in plant meiosis: role of eukaryotic RecA recombinases and their modulators. PLANT REPRODUCTION 2023; 36:17-41. [PMID: 35641832 DOI: 10.1007/s00497-022-00443-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 05/09/2022] [Indexed: 06/15/2023]
Abstract
Homologous recombination during meiosis is crucial for the DNA double-strand breaks (DSBs) repair that promotes the balanced segregation of homologous chromosomes and enhances genetic variation. In most eukaryotes, two recombinases RAD51 and DMC1 form nucleoprotein filaments on single-stranded DNA generated at DSB sites and play a central role in the meiotic DSB repair and genome stability. These nucleoprotein filaments perform homology search and DNA strand exchange to initiate repair using homologous template-directed sequences located elsewhere in the genome. Multiple factors can regulate the assembly, stability, and disassembly of RAD51 and DMC1 nucleoprotein filaments. In this review, we summarize the current understanding of the meiotic functions of RAD51 and DMC1 and the role of their positive and negative modulators. We discuss the current models and regulators of homology searches and strand exchange conserved during plant meiosis. Manipulation of these repair factors during plant meiosis also holds a great potential to accelerate plant breeding for crop improvements and productivity.
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Affiliation(s)
- Côme Emmenecker
- Institut Jean-Pierre Bourgin (IJPB), Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France
- University of Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Christine Mézard
- Institut Jean-Pierre Bourgin (IJPB), CNRS, Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France.
| | - Rajeev Kumar
- Institut Jean-Pierre Bourgin (IJPB), Université Paris-Saclay, INRAE, AgroParisTech, 78000, Versailles, France.
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9
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Franca MM, Condezo YB, Elzaiat M, Felipe-Medina N, Sánchez-Sáez F, Muñoz S, Sainz-Urruela R, Martín-Hervás MR, García-Valiente R, Sánchez-Martín MA, Astudillo A, Mendez J, Llano E, Veitia RA, Mendonca BB, Pendás AM. A truncating variant of RAD51B associated with primary ovarian insufficiency provides insights into its meiotic and somatic functions. Cell Death Differ 2022; 29:2347-2361. [PMID: 35624308 PMCID: PMC9751091 DOI: 10.1038/s41418-022-01021-z] [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: 10/28/2021] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/31/2023] Open
Abstract
Primary ovarian insufficiency (POI) causes female infertility by abolishing normal ovarian function. Although its genetic etiology has been extensively investigated, most POI cases remain unexplained. Using whole-exome sequencing, we identified a homozygous variant in RAD51B -(c.92delT) in two sisters with POI. In vitro studies revealed that this variant leads to translation reinitiation at methionine 64. Here, we show that this is a pathogenic hypomorphic variant in a mouse model. Rad51bc.92delT/c.92delT mice exhibited meiotic DNA repair defects due to RAD51 and HSF2BP/BMRE1 accumulation in the chromosome axes leading to a reduction in the number of crossovers. Interestingly, the interaction of RAD51B-c.92delT with RAD51C and with its newly identified interactors RAD51 and HELQ was abrogated or diminished. Repair of mitomycin-C-induced chromosomal aberrations was impaired in RAD51B/Rad51b-c.92delT human and mouse somatic cells in vitro and in explanted mouse bone marrow cells. Accordingly, Rad51b-c.92delT variant reduced replication fork progression of patient-derived lymphoblastoid cell lines and pluripotent reprogramming efficiency of primary mouse embryonic fibroblasts. Finally, Rad51bc.92delT/c.92delT mice displayed increased incidence of pituitary gland hyperplasia. These results provide new mechanistic insights into the role of RAD51B not only in meiosis but in the maintenance of somatic genome stability.
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Affiliation(s)
- Monica M Franca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42 and SELA, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brasil
- Section of Endocrinology Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, IL, USA
| | - Yazmine B Condezo
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Maëva Elzaiat
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France
| | - Natalia Felipe-Medina
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Fernando Sánchez-Sáez
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Sergio Muñoz
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Raquel Sainz-Urruela
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - M Rosario Martín-Hervás
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Rodrigo García-Valiente
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Manuel A Sánchez-Martín
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
- Transgenic Facility, Nucleus platform, Universidad de Salamanca, Salamanca, Spain
| | | | - Juan Mendez
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Elena Llano
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
- Departamento de Fisiología y Farmacología, Universidad de Salamanca, Salamanca, Spain
| | - Reiner A Veitia
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France.
- Université Paris-Saclay and Institut François Jacob, Comissariat à l'Energie Atomique, Gif-sur-Yvette, France.
| | - Berenice B Mendonca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42 and SELA, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brasil.
| | - Alberto M Pendás
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain.
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10
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Abstract
DNA polymerase θ (Pol θ) is a DNA repair enzyme widely conserved in animals and plants. Pol θ uses short DNA sequence homologies to initiate repair of double-strand breaks by theta-mediated end joining. The DNA polymerase domain of Pol θ is at the C terminus and is connected to an N-terminal DNA helicase-like domain by a central linker. Pol θ is crucial for maintenance of damaged genomes during development, protects DNA against extensive deletions, and limits loss of heterozygosity. The cost of using Pol θ for genome protection is that a few nucleotides are usually deleted or added at the repair site. Inactivation of Pol θ often enhances the sensitivity of cells to DNA strand-breaking chemicals and radiation. Since some homologous recombination-defective cancers depend on Pol θ for growth, inhibitors of Pol θ may be useful in treating such tumors.
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Affiliation(s)
- Richard D Wood
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, Texas, USA;
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington, Vermont, USA;
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11
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Vanson S, Li Y, Wood RD, Doublié S. Probing the structure and function of polymerase θ helicase-like domain. DNA Repair (Amst) 2022; 116:103358. [PMID: 35753097 PMCID: PMC10329254 DOI: 10.1016/j.dnarep.2022.103358] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/09/2022] [Accepted: 06/09/2022] [Indexed: 11/19/2022]
Abstract
DNA Polymerase θ is the key actuator of the recently identified double-strand break repair pathway, theta-mediated end joining (TMEJ). It is the only known polymerase to have a 3-domain architecture containing an independently functional family A DNA polymerase tethered by a long central region to an N-terminal helicase-like domain (HLD). Full-length polymerase θ and the isolated HLD hydrolyze ATP in the presence of DNA, but no processive DNA duplex unwinding has been observed. Based on sequence and structure conservation, the HLD is classified as a member of helicase superfamily II and, more specifically, the Ski2-like family. The specific subdomain composition and organization most closely resemble that of archaeal DNA repair helicases Hel308 and Hjm. The underlying structural basis as to why the HLD is not able to processively unwind duplex DNA, despite its similarity to bona fide helicases, remains elusive. Activities of the HLD include ATP hydrolysis, protein displacement, and annealing of complementary DNA. These observations have led to speculation about the role of the HLD within the context of double-strand break repair via TMEJ, such as removal of single-stranded DNA binding proteins like RPA and RAD51 and microhomology alignment. This review summarizes the structural classification and organization of the polymerase θ HLD and its homologs and explores emerging data on its biochemical activities. We conclude with a simple, speculative model for the HLD's role in TMEJ.
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Affiliation(s)
- Scott Vanson
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave, Burlington, VT 05405, USA
| | - Yuzhen Li
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, TX 77230, USA
| | - Richard D Wood
- Department of Epigenetics & Molecular Carcinogenesis, The University of Texas MD Anderson Center, Houston, TX 77230, USA.
| | - Sylvie Doublié
- Department of Microbiology and Molecular Genetics, University of Vermont, 89 Beaumont Ave, Burlington, VT 05405, USA.
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12
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Athar F, Templeman NM. C. elegans as a model organism to study female reproductive health. Comp Biochem Physiol A Mol Integr Physiol 2022; 266:111152. [PMID: 35032657 DOI: 10.1016/j.cbpa.2022.111152] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/04/2022] [Accepted: 01/07/2022] [Indexed: 12/17/2022]
Abstract
Female reproductive health has been historically understudied and underfunded. Here, we present the advantages of using a free-living nematode, Caenorhabditis elegans, as an animal system to study fundamental aspects of female reproductive health. C. elegans is a powerful high-throughput model organism that shares key genetic and physiological similarities with humans. In this review, we highlight areas of pressing medical and biological importance in the 21st century within the context of female reproductive health. These include the decline in female reproductive capacity with increasing chronological age, reproductive dysfunction arising from toxic environmental insults, and cancers of the reproductive system. C. elegans has been instrumental in uncovering mechanistic insights underlying these processes, and has been valuable for developing and testing therapeutics to combat them. Adopting a convenient model organism such as C. elegans for studying reproductive health will encourage further research into this field, and broaden opportunities for making advancements into evolutionarily conserved mechanisms that control reproductive function.
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Affiliation(s)
- Faria Athar
- Department of Biology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
| | - Nicole M Templeman
- Department of Biology, University of Victoria, Victoria, British Columbia V8P 5C2, Canada.
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13
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Division of Labor by the HELQ, BLM, and FANCM Helicases during Homologous Recombination Repair in Drosophila melanogaster. Genes (Basel) 2022; 13:genes13030474. [PMID: 35328029 PMCID: PMC8951532 DOI: 10.3390/genes13030474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/02/2022] [Accepted: 03/07/2022] [Indexed: 02/01/2023] Open
Abstract
Repair of DNA double-strand breaks by homologous recombination (HR) requires a carefully orchestrated sequence of events involving many proteins. One type of HR, synthesis-dependent strand annealing (SDSA), proceeds via the formation of a displacement loop (D-loop) when RAD51-coated single-stranded DNA invades a homologous template. The 3' end of the single-stranded DNA is extended by DNA synthesis. In SDSA, the D-loop is then disassembled prior to strand annealing. While many helicases can unwind D-loops in vitro, how their action is choreographed in vivo remains to be determined. To clarify the roles of various DNA helicases during SDSA, we used a double-strand gap repair assay to study the outcomes of homologous recombination repair in Drosophila melanogaster lacking the BLM, HELQ, and FANCM helicases. We found that the absence of any of these three helicases impairs gap repair. In addition, flies lacking both BLM and HELQ or HELQ and FANCM had more severe SDSA defects than the corresponding single mutants. In the absence of BLM, a large percentage of repair events were accompanied by flanking deletions. Strikingly, these deletions were mostly abolished in the blm helq and blm fancm double mutants. Our results suggest that the BLM, HELQ, and FANCM helicases play distinct roles during SDSA, with HELQ and FANCM acting early to promote the formation of recombination intermediates that are then processed by BLM to prevent repair by deletion-prone mechanisms.
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14
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Anand R, Buechelmaier E, Belan O, Newton M, Vancevska A, Kaczmarczyk A, Takaki T, Rueda DS, Powell SN, Boulton SJ. HELQ is a dual-function DSB repair enzyme modulated by RPA and RAD51. Nature 2022; 601:268-273. [PMID: 34937945 PMCID: PMC8755542 DOI: 10.1038/s41586-021-04261-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 11/17/2021] [Indexed: 02/04/2023]
Abstract
DNA double-stranded breaks (DSBs) are deleterious lesions, and their incorrect repair can drive cancer development1. HELQ is a superfamily 2 helicase with 3' to 5' polarity, and its disruption in mice confers germ cells loss, infertility and increased predisposition to ovarian and pituitary tumours2-4. At the cellular level, defects in HELQ result in hypersensitivity to cisplatin and mitomycin C, and persistence of RAD51 foci after DNA damage3,5. Notably, HELQ binds to RPA and the RAD51-paralogue BCDX2 complex, but the relevance of these interactions and how HELQ functions in DSB repair remains unclear3,5,6. Here we show that HELQ helicase activity and a previously unappreciated DNA strand annealing function are differentially regulated by RPA and RAD51. Using biochemistry analyses and single-molecule imaging, we establish that RAD51 forms a complex with and strongly stimulates HELQ as it translocates during DNA unwinding. By contrast, RPA inhibits DNA unwinding by HELQ but strongly stimulates DNA strand annealing. Mechanistically, we show that HELQ possesses an intrinsic ability to capture RPA-bound DNA strands and then displace RPA to facilitate annealing of complementary sequences. Finally, we show that HELQ deficiency in cells compromises single-strand annealing and microhomology-mediated end-joining pathways and leads to bias towards long-tract gene conversion tracts during homologous recombination. Thus, our results implicate HELQ in multiple arms of DSB repair through co-factor-dependent modulation of intrinsic translocase and DNA strand annealing activities.
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Affiliation(s)
- Roopesh Anand
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Erika Buechelmaier
- Memorial Sloan Kettering Cancer Center, New York, NY, USA
- Graduate School of Medical Sciences, Weill Cornell Medicine, New York, NY, USA
| | - Ondrej Belan
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - Matthew Newton
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK
| | | | - Artur Kaczmarczyk
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK
- Single Molecule Imaging Group, MRC-London Institute of Medical Sciences, London, UK
| | - Tohru Takaki
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK
| | - David S Rueda
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK.
- Single Molecule Imaging Group, MRC-London Institute of Medical Sciences, London, UK.
| | - Simon N Powell
- Memorial Sloan Kettering Cancer Center, New York, NY, USA.
| | - Simon J Boulton
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London, UK.
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15
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Helicase Q promotes homology-driven DNA double-strand break repair and prevents tandem duplications. Nat Commun 2021; 12:7126. [PMID: 34880204 PMCID: PMC8654963 DOI: 10.1038/s41467-021-27408-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Accepted: 11/16/2021] [Indexed: 11/09/2022] Open
Abstract
DNA double-strand breaks are a major threat to cellular survival and genetic integrity. In addition to high fidelity repair, three intrinsically mutagenic DNA break repair routes have been described, i.e. single-strand annealing (SSA), polymerase theta-mediated end-joining (TMEJ) and residual ill-defined microhomology-mediated end-joining (MMEJ) activity. Here, we identify C. elegans Helicase Q (HELQ-1) as being essential for MMEJ as well as for SSA. We also find HELQ-1 to be crucial for the synthesis-dependent strand annealing (SDSA) mode of homologous recombination (HR). Loss of HELQ-1 leads to increased genome instability: patchwork insertions arise at deletion junctions due to abortive rounds of polymerase theta activity, and tandem duplications spontaneously accumulate in genomes of helq-1 mutant animals as a result of TMEJ of abrogated HR intermediates. Our work thus implicates HELQ activity for all DSB repair modes guided by complementary base pairs and provides mechanistic insight into mutational signatures common in HR-defective cancers.
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16
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Mechanism of mitotic recombination: insights from C. elegans. Curr Opin Genet Dev 2021; 71:10-18. [PMID: 34186335 PMCID: PMC8683258 DOI: 10.1016/j.gde.2021.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 05/18/2021] [Accepted: 06/07/2021] [Indexed: 11/23/2022]
Abstract
Homologous recombination (HR) plays a critical role in largely error-free repair of mitotic and meiotic DNA double-strand breaks (DSBs). DSBs are one of the most deleterious DNA lesions, which are repaired by non-homologous end joining (NHEJ), homologous recombination (HR) or, if compromised, micro-homology mediated end joining (MMEJ). If left unrepaired, DSBs can lead to cell death or if repaired incorrectly can result in chromosome rearrangements that drive cancer development. Here, we describe recent advances in the field of mitotic HR made using Caenorhabditis elegans roundworm, as a model system.
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17
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Špírek M, Taylor MRG, Belan O, Boulton SJ, Krejci L. Nucleotide proofreading functions by nematode RAD51 paralogs facilitate optimal RAD51 filament function. Nat Commun 2021; 12:5545. [PMID: 34545070 PMCID: PMC8452638 DOI: 10.1038/s41467-021-25830-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 09/02/2021] [Indexed: 12/30/2022] Open
Abstract
The RAD51 recombinase assembles as helical nucleoprotein filaments on single-stranded DNA (ssDNA) and mediates invasion and strand exchange with homologous duplex DNA (dsDNA) during homologous recombination (HR), as well as protection and restart of stalled replication forks. Strand invasion by RAD51-ssDNA complexes depends on ATP binding. However, RAD51 can bind ssDNA in non-productive ADP-bound or nucleotide-free states, and ATP-RAD51-ssDNA complexes hydrolyse ATP over time. Here, we define unappreciated mechanisms by which the RAD51 paralog complex RFS-1/RIP-1 limits the accumulation of RAD-51-ssDNA complexes with unfavorable nucleotide content. We find RAD51 paralogs promote the turnover of ADP-bound RAD-51 from ssDNA, in striking contrast to their ability to stabilize productive ATP-bound RAD-51 nucleoprotein filaments. In addition, RFS-1/RIP-1 inhibits binding of nucleotide-free RAD-51 to ssDNA. We propose that ‘nucleotide proofreading’ activities of RAD51 paralogs co-operate to ensure the enrichment of active, ATP-bound RAD-51 filaments on ssDNA to promote HR. A RAD51 paralog complex, RFS-1/RIP-1, is shown to control ssDNA binding and dissociation by RAD-51 differentially in the presence and absence of nucleotide cofactors. These nucleotide proofreading activities drive a preferential accumulation of RAD-51-ssDNA complexes with optimal nucleotide content.
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Affiliation(s)
- Mário Špírek
- International Clinical Research Center, St. Anne's University Hospital in Brno, 62500, Brno, Czech Republic.,Department of Biology Masaryk University, 62500, Brno, Czech Republic
| | | | - Ondrej Belan
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.,National Centre for Biomolecular Research, Masaryk University, 62500, Brno, Czech Republic
| | - Simon J Boulton
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Lumir Krejci
- International Clinical Research Center, St. Anne's University Hospital in Brno, 62500, Brno, Czech Republic. .,Department of Biology Masaryk University, 62500, Brno, Czech Republic. .,National Centre for Biomolecular Research, Masaryk University, 62500, Brno, Czech Republic.
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18
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Zahn KE, Jensen RB. Polymerase θ Coordinates Multiple Intrinsic Enzymatic Activities during DNA Repair. Genes (Basel) 2021; 12:1310. [PMID: 34573292 PMCID: PMC8470613 DOI: 10.3390/genes12091310] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 11/16/2022] Open
Abstract
The POLQ gene encodes DNA polymerase θ, a 2590 amino acid protein product harboring DNA-dependent ATPase, template-dependent DNA polymerase, dNTP-dependent endonuclease, and 5'-dRP lyase functions. Polymerase θ participates at an essential step of a DNA double-strand break repair pathway able to join 5'-resected substrates by locating and pairing microhomologies present in 3'-overhanging single-stranded tails, cleaving the extraneous 3'-DNA by dNTP-dependent end-processing, before extending the nascent 3' end from the microhomology annealing site. Metazoans require polymerase θ for full resistance to DNA double-strand break inducing agents but can survive knockout of the POLQ gene. Cancer cells with compromised homologous recombination, or other DNA repair defects, over-utilize end-joining by polymerase θ and often over-express the POLQ gene. This dependency points to polymerase θ as an ideal drug target candidate and multiple drug-development programs are now preparing to enter clinical trials with small-molecule inhibitors. Specific inhibitors of polymerase θ would not only be predicted to treat BRCA-mutant cancers, but could thwart accumulated resistance to current standard-of-care cancer therapies and overcome PARP-inhibitor resistance in patients. This article will discuss synthetic lethal strategies targeting polymerase θ in DNA damage-response-deficient cancers and summarize data, describing molecular structures and enzymatic functions.
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Affiliation(s)
- Karl E. Zahn
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
- Repare Therapeutics, 7210 Rue Frederick Banting, Montreal, QC H4S 2A1, Canada
| | - Ryan B. Jensen
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
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19
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Counteracting Environmental Chemicals with Coenzyme Q10: An Educational Primer for Use with "Antioxidant CoQ10 Restores Fertility by Rescuing Bisphenol A-Induced Oxidative DNA Damage in the Caenorhabditis elegans Germline". Genetics 2021; 216:879-890. [PMID: 33268390 DOI: 10.1534/genetics.120.303577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 09/05/2020] [Indexed: 02/08/2023] Open
Abstract
Environmental toxicants are chemicals that negatively affect human health. Although there are numerous ways to limit exposure, the ubiquitous nature of certain environmental toxicants makes it impossible to avoid them entirely. Consequently, scientists are continuously working toward developing strategies for combating their harmful effects. Using the nematode Caenorhabditis elegans, a model with many genetic and physiological similarities to humans, researchers in the Colaiácovo laboratory have identified several molecular mechanisms by which the toxic agent bisphenol A (BPA) interferes with reproduction. Here, we address their recent discovery that a widely available compound, Coenzyme Q10 (CoQ10), can rescue BPA-induced damage. This work is significant in that it poses a low-cost method for improving reproductive success in humans. The goal of this primer is to assist educators and students with navigating the paper entitled "Antioxidant CoQ10 Restores Fertility by Rescuing Bisphenol A-Induced Oxidative DNA Damage in the Caenorhabditis elegans Germline." It is ideally suited for integration into an upper-level undergraduate course such as Genetics, Cell and Molecular Biology, Developmental Biology, or Toxicology. The primer provides background information on the history of BPA, the utility of the C. elegans germ line as a model for studying reproductive toxicity, and research methods including assessment of programmed cell death, fluorescent microscopy applications, and assays to quantify gene expression. Questions for deeper exploration in-class or online are provided.Related article in GENETICS: Hornos Carneiro MF, Shin N, Karthikraj R, Barbosa F Jr, Kannan K, Colaiácovo MP. Antioxidant CoQ10 restores fertility by rescuing bisphenol A-induced oxidative DNA damage in the Caenorhabditis elegans Germline. Genetics 214:381-395.
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20
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Carver A, Zhang X. Rad51 filament dynamics and its antagonistic modulators. Semin Cell Dev Biol 2021; 113:3-13. [PMID: 32631783 DOI: 10.1016/j.semcdb.2020.06.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/10/2020] [Accepted: 06/20/2020] [Indexed: 02/07/2023]
Abstract
Rad51 recombinase is the central player in homologous recombination, the faithful repair pathway for double-strand breaks and key event during meiosis. Rad51 forms nucleoprotein filaments on single-stranded DNA, exposed by a double-strand break. These filaments are responsible for homology search and strand invasion, which lead to homology-directed repair. Due to its central roles in DNA repair and genome stability, Rad51 is modulated by multiple factors and post-translational modifications. In this review, we summarize our current understanding of the dynamics of Rad51 filaments, the roles of other factors and their modes of action in modulating key stages of Rad51 filaments: formation, stability and disassembly.
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Affiliation(s)
- Alexander Carver
- Section of Structural Biology, Department of Infectious Diseases, Sir Alexander Fleming Building, Imperial College London, SW7 2AZ, UK
| | - Xiaodong Zhang
- Section of Structural Biology, Department of Infectious Diseases, Sir Alexander Fleming Building, Imperial College London, SW7 2AZ, UK.
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21
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Meier B, Volkova NV, Hong Y, Bertolini S, González-Huici V, Petrova T, Boulton S, Campbell PJ, Gerstung M, Gartner A. Protection of the C. elegans germ cell genome depends on diverse DNA repair pathways during normal proliferation. PLoS One 2021; 16:e0250291. [PMID: 33905417 PMCID: PMC8078821 DOI: 10.1371/journal.pone.0250291] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 04/01/2021] [Indexed: 12/13/2022] Open
Abstract
Maintaining genome integrity is particularly important in germ cells to ensure faithful transmission of genetic information across generations. Here we systematically describe germ cell mutagenesis in wild-type and 61 DNA repair mutants cultivated over multiple generations. ~44% of the DNA repair mutants analysed showed a >2-fold increased mutagenesis with a broad spectrum of mutational outcomes. Nucleotide excision repair deficiency led to higher base substitution rates, whereas polh-1(Polη) and rev-3(Polζ) translesion synthesis polymerase mutants resulted in 50-400 bp deletions. Signatures associated with defective homologous recombination fall into two classes: 1) brc-1/BRCA1 and rad-51/RAD51 paralog mutants showed increased mutations across all mutation classes, 2) mus-81/MUS81 and slx-1/SLX1 nuclease, and him-6/BLM, helq-1/HELQ or rtel-1/RTEL1 helicase mutants primarily accumulated structural variants. Repetitive and G-quadruplex sequence-containing loci were more frequently mutated in specific DNA repair backgrounds. Tandem duplications embedded in inverted repeats were observed in helq-1 helicase mutants, and a unique pattern of 'translocations' involving homeologous sequences occurred in rip-1 recombination mutants. atm-1/ATM checkpoint mutants harboured structural variants specifically enriched in subtelomeric regions. Interestingly, locally clustered mutagenesis was only observed for combined brc-1 and cep-1/p53 deficiency. Our study provides a global view of how different DNA repair pathways contribute to prevent germ cell mutagenesis.
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Affiliation(s)
- Bettina Meier
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland
| | - Nadezda V. Volkova
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, United Kingdom
| | - Ye Hong
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland
| | - Simone Bertolini
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland
| | | | - Tsvetana Petrova
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland
| | | | - Peter J. Campbell
- Cancer, Ageing and Somatic Mutation Program, Wellcome Sanger Institute, Hinxton, United Kingdom
- Department of Haematology, University of Cambridge, Cambridge, United Kingdom
- Department of Haematology, Addenbrooke’s Hospital, Cambridge, United Kingdom
| | - Moritz Gerstung
- European Molecular Biology Laboratory, European Bioinformatics Institute, Hinxton, United Kingdom
- European Molecular Biology Laboratory, Genome Biology Unit, Heidelberg, Germany
| | - Anton Gartner
- Centre for Gene Regulation and Expression, University of Dundee, Dundee, Scotland
- Department of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
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22
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Gartner A, Engebrecht J. DNA repair, recombination, and damage signaling. Genetics 2021; 220:6522877. [PMID: 35137093 PMCID: PMC9097270 DOI: 10.1093/genetics/iyab178] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 10/10/2021] [Indexed: 01/09/2023] Open
Abstract
DNA must be accurately copied and propagated from one cell division to the next, and from one generation to the next. To ensure the faithful transmission of the genome, a plethora of distinct as well as overlapping DNA repair and recombination pathways have evolved. These pathways repair a large variety of lesions, including alterations to single nucleotides and DNA single and double-strand breaks, that are generated as a consequence of normal cellular function or by external DNA damaging agents. In addition to the proteins that mediate DNA repair, checkpoint pathways have also evolved to monitor the genome and coordinate the action of various repair pathways. Checkpoints facilitate repair by mediating a transient cell cycle arrest, or through initiation of cell suicide if DNA damage has overwhelmed repair capacity. In this chapter, we describe the attributes of Caenorhabditis elegans that facilitate analyses of DNA repair, recombination, and checkpoint signaling in the context of a whole animal. We review the current knowledge of C. elegans DNA repair, recombination, and DNA damage response pathways, and their role during development, growth, and in the germ line. We also discuss how the analysis of mutational signatures in C. elegans is helping to inform cancer mutational signatures in humans.
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Affiliation(s)
- Anton Gartner
- Department for Biological Sciences, IBS Center for Genomic Integrity, Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea,Corresponding author: (A.G.); (J.E.)
| | - JoAnne Engebrecht
- Department of Molecular and Cellular Biology, University of California Davis, Davis, CA 95616, USA,Corresponding author: (A.G.); (J.E.)
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23
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Jenkins T, Northall SJ, Ptchelkine D, Lever R, Cubbon A, Betts H, Taresco V, Cooper CDO, McHugh PJ, Soultanas P, Bolt EL. The HelQ human DNA repair helicase utilizes a PWI-like domain for DNA loading through interaction with RPA, triggering DNA unwinding by the HelQ helicase core. NAR Cancer 2021; 3:zcaa043. [PMID: 34316696 PMCID: PMC8210318 DOI: 10.1093/narcan/zcaa043] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 11/30/2020] [Accepted: 12/16/2020] [Indexed: 01/04/2023] Open
Abstract
Genome instability is a characteristic enabling factor for carcinogenesis. HelQ helicase is a component of human DNA maintenance systems that prevent or reverse genome instability arising during DNA replication. Here, we provide details of the molecular mechanisms that underpin HelQ function-its recruitment onto ssDNA through interaction with replication protein A (RPA), and subsequent translocation of HelQ along ssDNA. We describe for the first time a functional role for the non-catalytic N-terminal region of HelQ, by identifying and characterizing its PWI-like domain. We present evidence that this domain of HelQ mediates interaction with RPA that orchestrates loading of the helicase domains onto ssDNA. Once HelQ is loaded onto the ssDNA, ATP-Mg2+ binding in the catalytic site activates the helicase core and triggers translocation along ssDNA as a dimer. Furthermore, we identify HelQ-ssDNA interactions that are critical for the translocation mechanism. Our data are novel and detailed insights into the mechanisms of HelQ function relevant for understanding how human cells avoid genome instability provoking cancers, and also how cells can gain resistance to treatments that rely on DNA crosslinking agents.
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Affiliation(s)
- Tabitha Jenkins
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Sarah J Northall
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | | | - Rebecca Lever
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Andrew Cubbon
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
| | - Hannah Betts
- School of Chemistry, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Vincenzo Taresco
- School of Pharmacy, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Christopher D O Cooper
- Department of Biological and Geographical Sciences, School of Applied Sciences, The University of Huddersfield, HD1 3DH, Huddersfield, UK
| | - Peter J McHugh
- MRC Weatherall Institute of Molecular Medicine (WIMM), University of Oxford, OX3 9DS, Oxford, UK
| | - Panos Soultanas
- School of Chemistry, The University of Nottingham, NG7 2RD, Nottingham, UK
| | - Edward L Bolt
- School of Life Sciences, The University of Nottingham, NG7 2UH, Nottingham, UK
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24
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Huselid E, Bunting SF. The Regulation of Homologous Recombination by Helicases. Genes (Basel) 2020; 11:genes11050498. [PMID: 32369918 PMCID: PMC7290689 DOI: 10.3390/genes11050498] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 11/16/2022] Open
Abstract
Homologous recombination is essential for DNA repair, replication and the exchange of genetic material between parental chromosomes during meiosis. The stages of recombination involve complex reorganization of DNA structures, and the successful completion of these steps is dependent on the activities of multiple helicase enzymes. Helicases of many different families coordinate the processing of broken DNA ends, and the subsequent formation and disassembly of the recombination intermediates that are necessary for template-based DNA repair. Loss of recombination-associated helicase activities can therefore lead to genomic instability, cell death and increased risk of tumor formation. The efficiency of recombination is also influenced by the ‘anti-recombinase’ effect of certain helicases, which can direct DNA breaks toward repair by other pathways. Other helicases regulate the crossover versus non-crossover outcomes of repair. The use of recombination is increased when replication forks and the transcription machinery collide, or encounter lesions in the DNA template. Successful completion of recombination in these situations is also regulated by helicases, allowing normal cell growth, and the maintenance of genomic integrity.
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Abstract
This Outlook discusses the findings by Hustedt et al. in this issue of Genes & Development that report the identification of HROB, a novel factor required for loading MCM8–9 onto HR intermediates to facilitate DNA repair synthesis. Homologous recombination (HR) is an important route for repairing DNA double-strand breaks (DSBs). The early stages of HR are well understood, but later stages remain mysterious. In this issue of Genes & Development, Hustedt and colleagues (pp. 1397–1415) reveal HROB as a new player in HR required for recruitment of the MCM8–9 complex, which is paralogous to the MCM2–7 replicative helicase. HROB functions closely with MCM8–9 to promote postsynaptic DNA repair synthesis. This study sheds valuable light on late events in HR and suggests that HROB may load MCM8–9 onto HR intermediates to facilitate the DNA unwinding required for DNA repair synthesis.
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Affiliation(s)
- Giulia Saredi
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom
| | - John Rouse
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom
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Tian M, Loidl J. An MCM family protein promotes interhomolog recombination by preventing precocious intersister repair of meiotic DSBs. PLoS Genet 2019; 15:e1008514. [PMID: 31815942 PMCID: PMC6922451 DOI: 10.1371/journal.pgen.1008514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Revised: 12/19/2019] [Accepted: 11/11/2019] [Indexed: 12/02/2022] Open
Abstract
Recombinational repair of meiotic DNA double-strand breaks (DSBs) uses the homologous chromosome as a template, although the sister chromatid offers itself as a spatially more convenient substrate. In many organisms, this choice is reinforced by the recombination protein Dmc1. In Tetrahymena, the repair of DSBs, which are formed early in prophase, is postponed to late prophase when homologous chromosomes and sister chromatids become juxtaposed owing to tight parallel packing in the thread-shaped nucleus, and thus become equally suitable for use as repair templates. The delay in DSB repair is achieved by rejection of the invading strand by the Sgs1 helicase in early meiotic prophase. In the absence of Mcmd1, a meiosis-specific minichromosome maintenance (MCM)-like protein (and its partner Pamd1), Dmc1 is prematurely lost from chromatin and DNA synthesis (as monitored by BrdU incorporation) takes place in early prophase. In mcmd1Δ and pamd1Δ mutants, only a few crossovers are formed. In a mcmd1Δ hop2Δ double mutant, normal timing of Dmc1 loss and DNA synthesis is restored. Because Tetrahymena Hop2 is believed to enable homologous strand invasion, we conclude that Dmc1 loss in the absence of Mcmd1 affects only post-invasion recombination intermediates. Therefore, we propose that the Dmc1 nucleofilament becomes dismantled immediately after forming a heteroduplex with a template strand. As a consequence, repair synthesis and D-loop extension starts in early prophase intermediates and prevents strand rejection before the completion of homologous pairing. In this case, DSB repair may primarily use the sister chromatid. We conclude that Mcmd1‒Pamd1 protects the Dmc1 nucleofilament from premature dismantling, thereby suppressing precocious repair synthesis and excessive intersister strand exchange at the cost of homologous recombination. Minichromosome maintenance (MCM) proteins are mainly known for their involvement in DNA replication. However, distant members of this protein family have recently been shown to promote interhomolog over intersister recombination in meiosis. They achieve this by enforcing or stabilizing the invasion of a double-stranded DNA by a filament consisting of a homologous single-stranded DNA molecule coated with a strand exchange protein. This interaction then would lead to the exchange of DNA strands and, ultimately, crossing over. Here, we study a member of the MCM protein family in the protist Tetrahymena thermophila. Meiosis in this organism has several unusual features: A synaptonemal complex is not formed, and homologous prealignment occurs during the close parallel arrangement of chromosomes in the extremely elongated, threadlike meiotic prophase nucleus. This noncanonical pairing has come along with altered mechanisms for recombination partner choice. Thus, we find that the Tetrahymena meiotic MCM protein promotes crossovers in an unprecedented way: It suppresses the formation of recombination intermediates between sister DNA molecules early in meiosis, thereby increasing the chance of competing interhomolog recombination events. Thus, members of the same protein family have been harnessed by different organisms to achieve the same result via completely different mechanisms.
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Affiliation(s)
- Miao Tian
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Josef Loidl
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
- * E-mail:
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Steinfeld JB, Beláň O, Kwon Y, Terakawa T, Al-Zain A, Smith MJ, Crickard JB, Qi Z, Zhao W, Rothstein R, Symington LS, Sung P, Boulton SJ, Greene EC. Defining the influence of Rad51 and Dmc1 lineage-specific amino acids on genetic recombination. Genes Dev 2019; 33:1191-1207. [PMID: 31371435 PMCID: PMC6719624 DOI: 10.1101/gad.328062.119] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 07/01/2019] [Indexed: 02/06/2023]
Abstract
The vast majority of eukaryotes possess two DNA recombinases: Rad51, which is ubiquitously expressed, and Dmc1, which is meiosis-specific. The evolutionary origins of this two-recombinase system remain poorly understood. Interestingly, Dmc1 can stabilize mismatch-containing base triplets, whereas Rad51 cannot. Here, we demonstrate that this difference can be attributed to three amino acids conserved only within the Dmc1 lineage of the Rad51/RecA family. Chimeric Rad51 mutants harboring Dmc1-specific amino acids gain the ability to stabilize heteroduplex DNA joints with mismatch-containing base triplets, whereas Dmc1 mutants with Rad51-specific amino acids lose this ability. Remarkably, RAD-51 from Caenorhabditis elegans, an organism without Dmc1, has acquired "Dmc1-like" amino acids. Chimeric C. elegans RAD-51 harboring "canonical" Rad51 amino acids gives rise to toxic recombination intermediates, which must be actively dismantled to permit normal meiotic progression. We propose that Dmc1 lineage-specific amino acids involved in the stabilization of heteroduplex DNA joints with mismatch-containing base triplets may contribute to normal meiotic recombination.
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Affiliation(s)
- Justin B Steinfeld
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Ondrej Beláň
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Youngho Kwon
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Tsuyoshi Terakawa
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Amr Al-Zain
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Michael J Smith
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - J Brooks Crickard
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Zhi Qi
- Center for Quantitative Biology, Peking University-Tsinghua University Joint Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Weixing Zhao
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Rodney Rothstein
- Department of Genetics and Development, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Lorraine S Symington
- Department of Microbiology and Immunology, Columbia University Irving Medical Center, New York, New York 10032, USA
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, USA
| | - Simon J Boulton
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London NW1 1AT, United Kingdom
| | - Eric C Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, New York 10032, USA
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Hustedt N, Saito Y, Zimmermann M, Álvarez-Quilón A, Setiaputra D, Adam S, McEwan A, Yuan JY, Olivieri M, Zhao Y, Kanemaki MT, Jurisicova A, Durocher D. Control of homologous recombination by the HROB-MCM8-MCM9 pathway. Genes Dev 2019; 33:1397-1415. [PMID: 31467087 PMCID: PMC6771392 DOI: 10.1101/gad.329508.119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/08/2019] [Indexed: 12/17/2022]
Abstract
In this study, Hustedt et al. use CRISPR-based genetic screens to build a clear picture of the postsynaptic steps of homologous recombination in mammalian cells. They report the identification of C17orf53/HROB, a factor required for cell survival after exposure to a variety of replication stress-inducing genotoxins and for the resolution but not formation of Rad51 foci. DNA repair by homologous recombination (HR) is essential for genomic integrity, tumor suppression, and the formation of gametes. HR uses DNA synthesis to repair lesions such as DNA double-strand breaks and stalled DNA replication forks, but despite having a good understanding of the steps leading to homology search and strand invasion, we know much less of the mechanisms that establish recombination-associated DNA polymerization. Here, we report that C17orf53/HROB is an OB-fold-containing factor involved in HR that acts by recruiting the MCM8–MCM9 helicase to sites of DNA damage to promote DNA synthesis. Mice with targeted mutations in Hrob are infertile due to depletion of germ cells and display phenotypes consistent with a prophase I meiotic arrest. The HROB–MCM8–MCM9 pathway acts redundantly with the HELQ helicase, and cells lacking both HROB and HELQ have severely impaired HR, suggesting that they underpin two major routes for the completion of HR downstream from RAD51. The function of HROB in HR is reminiscent of that of gp59, which acts as the replicative helicase loader during bacteriophage T4 recombination-dependent DNA replication. We therefore propose that the loading of MCM8–MCM9 by HROB may similarly be a key step in the establishment of mammalian recombination-associated DNA synthesis.
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Affiliation(s)
- Nicole Hustedt
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Yuichiro Saito
- Department of Chromosome Science, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan
| | - Michal Zimmermann
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | | | - Dheva Setiaputra
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Salomé Adam
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Andrea McEwan
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Jing Yi Yuan
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada
| | - Michele Olivieri
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Yichao Zhao
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Masato T Kanemaki
- Department of Chromosome Science, National Institute of Genetics, Mishima, Shizuoka 411-8540, Japan.,Department of Genetics, SOKENDAI, Mishima, Shizuoka 411-8540, Japan
| | - Andrea Jurisicova
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.,Department of Physiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada.,Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario M5G 0D8, Canada
| | - Daniel Durocher
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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ATM and ATR Influence Meiotic Crossover Formation Through Antagonistic and Overlapping Functions in Caenorhabditis elegans. Genetics 2019; 212:431-443. [PMID: 31015193 DOI: 10.1534/genetics.119.302193] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 04/14/2019] [Indexed: 01/08/2023] Open
Abstract
During meiosis, formation of double-strand breaks (DSBs) and repair by homologous recombination between homologs creates crossovers (COs) that facilitate chromosome segregation. CO formation is tightly regulated to ensure the integrity of this process. The DNA damage response kinases, Ataxia-telangiectasia mutated (ATM) and RAD3-related (ATR) have emerged as key regulators of CO formation in yeast, flies, and mice, influencing DSB formation, repair pathway choice, and cell cycle progression. The molecular networks that ATM and ATR influence during meiosis are still being resolved in other organisms. Here, we show that Caenorhabditis elegans ATM and ATR homologs, ATM-1 and ATL-1 respectively, act at multiple steps in CO formation to ultimately ensure that COs are formed on all chromosomes. We show a role for ATM-1 in regulating the choice of repair template, biasing use of the homologous chromosome instead of the sister chromatid. Our data suggest a model in which ATM-1 and ATL-1 have antagonistic roles in very early repair processing, but are redundantly required for accumulation of the RAD-51 recombinase at DSB sites. We propose that these features of ATM-1 and ATL-1 ensure both CO formation on all chromosomes and accurate repair of additional DSBs.
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Griffin WC, Trakselis MA. The MCM8/9 complex: A recent recruit to the roster of helicases involved in genome maintenance. DNA Repair (Amst) 2019; 76:1-10. [PMID: 30743181 DOI: 10.1016/j.dnarep.2019.02.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 02/03/2019] [Indexed: 12/11/2022]
Abstract
There are several DNA helicases involved in seemingly overlapping aspects of homologous and homoeologous recombination. Mutations of many of these helicases are directly implicated in genetic diseases including cancer, rapid aging, and infertility. MCM8/9 are recent additions to the catalog of helicases involved in recombination, and so far, the evidence is sparse, making assignment of function difficult. Mutations in MCM8/9 correlate principally with primary ovarian failure/insufficiency (POF/POI) and infertility indicating a meiotic defect. However, they also act when replication forks collapse/break shuttling products into mitotic recombination and several mutations are found in various somatic cancers. This review puts MCM8/9 in context with other replication and recombination helicases to narrow down its genomic maintenance role. We discuss the known structure/function relationship, the mutational spectrum, and dissect the available cellular and organismal data to better define its role in recombination.
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Affiliation(s)
- Wezley C Griffin
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798, USA
| | - Michael A Trakselis
- Department of Chemistry and Biochemistry, Baylor University, Waco, Texas, 76798, USA.
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31
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Shu complex SWS1-SWSAP1 promotes early steps in mouse meiotic recombination. Nat Commun 2018; 9:3961. [PMID: 30305635 PMCID: PMC6180034 DOI: 10.1038/s41467-018-06384-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 08/24/2018] [Indexed: 12/25/2022] Open
Abstract
The DNA-damage repair pathway homologous recombination (HR) requires factors that promote the activity of strand-exchange protein RAD51 and its meiosis-specific homolog DMC1. Here we show that the Shu complex SWS1-SWSAP1, a candidate for one such HR regulator, is dispensable for mouse viability but essential for male and female fertility, promoting the assembly of RAD51 and DMC1 on early meiotic HR intermediates. Only a fraction of mutant meiocytes progress to form crossovers, which are crucial for chromosome segregation, demonstrating crossover homeostasis. Remarkably, loss of the DNA damage checkpoint kinase CHK2 rescues fertility in females without rescuing crossover numbers. Concomitant loss of the BRCA2 C terminus aggravates the meiotic defects in Swsap1 mutant spermatocytes, suggesting an overlapping role with the Shu complex during meiotic HR. These results demonstrate an essential role for SWS1-SWSAP1 in meiotic progression and emphasize the complex interplay of factors that ensure recombinase function. Homologous recombination ensures genome integrity during meiotic recombination. Here the authors reveal that factors SWS1 and SWSAP1 are critical for meiotic homologues recombination, particularly in promoting assembly of RAD51 and DMC1 on early recombination intermediates.
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32
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Meiotic Double-Strand Break Proteins Influence Repair Pathway Utilization. Genetics 2018; 210:843-856. [PMID: 30242011 DOI: 10.1534/genetics.118.301402] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/13/2018] [Indexed: 12/13/2022] Open
Abstract
Double-strand breaks (DSBs) are among the most deleterious lesions DNA can endure. Yet, DSBs are programmed at the onset of meiosis, and are required to facilitate appropriate reduction of ploidy in daughter cells. Repair of these breaks is tightly controlled to favor homologous recombination (HR)-the only repair pathway that can form crossovers. However, little is known about how the activities of alternative repair pathways are regulated at these stages. We discovered an unexpected synthetic interaction between the DSB machinery and strand-exchange proteins. Depleting the Caenorhabditis elegans DSB-promoting factors HIM-5 and DSB-2 suppresses the formation of chromosome fusions that arise in the absence of RAD-51 or other strand-exchange mediators. Our investigations reveal that nonhomologous and theta-mediated end joining (c-NHEJ and TMEJ, respectively) and single strand annealing (SSA) function redundantly to repair DSBs when HR is compromised, and that HIM-5 influences the utilization of TMEJ and SSA.
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33
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Sun L, Sun G, Shi C, Sun D. Transcriptome analysis reveals new microRNAs-mediated pathway involved in anther development in male sterile wheat. BMC Genomics 2018; 19:333. [PMID: 29739311 PMCID: PMC5941544 DOI: 10.1186/s12864-018-4727-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Accepted: 04/25/2018] [Indexed: 11/16/2022] Open
Abstract
Background 337S is a novel bi-pole-photo-thermo-sensitive genic male sterile line in wheat, and sensitive to both long day length/high temperature and short day length/low temperature condition. Although the regulatory function of MicroRNAs (miRNAs) in reproductive development has been increasingly studied, their roles in pre-meiotic and meiotic cells formation of plants have not been clearly explored. Here, we explored the roles of miRNAs in regulating male sterility of 337S at short day length/low temperature condition. Results Small RNA sequencing and degradome analyses were employed to identify miRNAs and their targets in the 337S whose meiotic cells collapsed rapidly during male meiotic prophase, resulting in failure of meiosis at SL condition. A total of 102 unique miRNAs were detected. Noticeably, the largest miRNA family was MiR1122. The target CCR4-associated factor 1 (CAF1) of miR2275, a subunit of the Carbon Catabolite Repressed 4-Negative on TATA-less (CCR4-NOT) complex, contributes to the process of early meiosis, and was first identified here. Further studies showed that the expression of several pivotal anther-related miRNAs was altered in 337S at SL condition, especially tae-miR1127a, which may be related to male sterility of 337S. Here, we also identified a new member of SWI/SNF factors SWI/SNF-related matrix-associated actin-dependent regulator of chromatin subfamily A, member 3-like 3 (SMARCA3L3) targeted by tae-miR1127a, whose function might be involved in faithful progression of meiosis in male reproductive cells. Conclusion The miRNA-target interactions of tae-miR2275-CAF1 and tae-miR1127a-SMARCA3L3 might be involved in regulating male fertility in 337S. Our results also implied that multiple roles for SMARCA3L3 and CAF1 in DNA repair and transcriptional regulation jointly orchestrated a tight and orderly system for maintaining chromatin and genome integrity during meiosis. Electronic supplementary material The online version of this article (10.1186/s12864-018-4727-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Longqing Sun
- College of plant science & technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Genlou Sun
- Biology Department, Saint Mary's University, Halifax, Nova Scotia, B3H 3C3, Canada
| | - Chenxia Shi
- College of plant science & technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China
| | - Dongfa Sun
- College of plant science & technology, Huazhong Agricultural University, Wuhan, 430070, Hubei, China. .,Hubei Collaborative Innovation Center for Grain Industry, Jingzhou, 434025, Hubei, China.
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The Role of Blm Helicase in Homologous Recombination, Gene Conversion Tract Length, and Recombination Between Diverged Sequences in Drosophilamelanogaster. Genetics 2017; 207:923-933. [PMID: 28912341 DOI: 10.1534/genetics.117.300285] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 09/10/2017] [Indexed: 11/18/2022] Open
Abstract
DNA double-strand breaks (DSBs) are a particularly deleterious class of DNA damage that threatens genome integrity. DSBs are repaired by three pathways: nonhomologous-end joining (NHEJ), homologous recombination (HR), and single-strand annealing (SSA). Drosophila melanogaster Blm (DmBlm) is the ortholog of Saccharomyces cerevisiae SGS1 and human BLM, and has been shown to suppress crossovers in mitotic cells and repair mitotic DNA gaps via HR. To further elucidate the role of DmBlm in repair of a simple DSB, and in particular recombination mechanisms, we utilized the Direct Repeat of white (DR-white) and Direct Repeat of whitewith mutations (DR-white.mu) repair assays in multiple mutant allele backgrounds. DmBlm null and helicase-dead mutants both demonstrated a decrease in repair by noncrossover HR, and a concurrent increase in non-HR events, possibly including SSA, crossovers, deletions, and NHEJ, although detectable processing of the ends was not significantly impacted. Interestingly, gene conversion tract lengths of HR repair events were substantially shorter in DmBlm null but not helicase-dead mutants, compared to heterozygote controls. Using DR-white.mu, we found that, in contrast to Sgs1, DmBlm is not required for suppression of recombination between diverged sequences. Taken together, our data suggest that DmBlm helicase function plays a role in HR, and the steps that contribute to determining gene conversion tract length are helicase-independent.
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35
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Northall SJ, Buckley R, Jones N, Penedo JC, Soultanas P, Bolt EL. DNA binding and unwinding by Hel308 helicase requires dual functions of a winged helix domain. DNA Repair (Amst) 2017; 57:125-132. [DOI: 10.1016/j.dnarep.2017.07.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/11/2017] [Accepted: 07/12/2017] [Indexed: 12/23/2022]
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36
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CRISPR Technology Reveals RAD(51)-ical Mechanisms of Repair in Roundworms: An Educational Primer for Use with "Promotion of Homologous Recombination by SWS-1 in Complex with RAD-51 Paralogs in Caenorhabditis elegans". Genetics 2017; 204:883-891. [PMID: 28114101 DOI: 10.1534/genetics.116.195479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The mechanisms cells use to maintain genetic fidelity via DNA repair and the accuracy of these processes have garnered interest from scientists engaged in basic research to clinicians seeking improved treatment for cancer patients. Despite the continued advances, many details of DNA repair are still incompletely understood. In addition, the inherent complexity of DNA repair processes, even at the most fundamental level, makes it a challenging topic. This primer is meant to assist both educators and students in using a recent paper, "Promotion of homologous recombination by SWS-1 in complex with RAD-51 paralogs in Caenorhabditis elegans," to understand mechanisms of DNA repair. The goals of this primer are to highlight and clarify several key techniques utilized, with special emphasis on the clustered, regularly interspaced, short palindromic repeats technique and the ways in which it has revolutionized genetics research, as well as to provide questions for deeper in-class discussion.
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Abstract
Sexual reproduction requires the production of haploid gametes (sperm and egg) with only one copy of each chromosome; fertilization then restores the diploid chromosome content in the next generation. This reduction in genetic content is accomplished during a specialized cell division called meiosis, in which two rounds of chromosome segregation follow a single round of DNA replication. In preparation for the first meiotic division, homologous chromosomes pair and synapse, creating a context that promotes formation of crossover recombination events. These crossovers, in conjunction with sister chromatid cohesion, serve to connect the two homologs and facilitate their segregation to opposite poles during the first meiotic division. During the second meiotic division, which is similar to mitosis, sister chromatids separate; the resultant products are haploid cells that become gametes. In Caenorhabditis elegans (and most other eukaryotes) homologous pairing and recombination are required for proper chromosome inheritance during meiosis; accordingly, the events of meiosis are tightly coordinated to ensure the proper execution of these events. In this chapter, we review the seminal events of meiosis: pairing of homologous chromosomes, the changes in chromosome structure that chromosomes undergo during meiosis, the events of meiotic recombination, the differentiation of homologous chromosome pairs into structures optimized for proper chromosome segregation at Meiosis I, and the ultimate segregation of chromosomes during the meiotic divisions. We also review the regulatory processes that ensure the coordinated execution of these meiotic events during prophase I.
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Affiliation(s)
- Kenneth J Hillers
- Biological Sciences Department, California Polytechnic State University, San Luis Obispo, CA 93407, United States
| | - Verena Jantsch
- Department of Chromosome Biology, Max F. Perutz Laboratories, University of Vienna, Vienna Biocenter,1030 Vienna, Austria
| | | | - Judith L Yanowitz
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, United States
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38
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Ramezani S, Shirdel A, Rafatpanah H, Akbarin MM, Tarokhian H, Rahimi H, Bari A, Jahantigh HR, Rezaee SA. Assessment of HTLV-1 proviral load, LAT, BIM, c-FOS and RAD51 gene expression in adult T cell leukemia/lymphoma. Med Microbiol Immunol 2017; 206:327-335. [PMID: 28466382 DOI: 10.1007/s00430-017-0506-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 04/17/2017] [Indexed: 12/13/2022]
Abstract
Adult T cell leukemia/lymphoma (ATLL) is a life-threatening malignancy of HTLV-1 infected Th lymphocytes. In the present study host-virus interactions were investigated by assessment of HTLV-1 proviral load (PVL) and host gene expression. A cross-sectional study was carried out on 18 ATLL, 10 HAM/TSP patients and 18 HTLV-1 asymptomatic carriers (ACs). DNA and mRNA of the peripheral blood mononuclear cells were extracted for PVL and LAT, BIM, c-FOS and RAD51 gene expression measurement using qRT-PCR. The mean PVL in ATLL patients was 11,430 ± 3770 copies/104 which was statistically higher than ACs, 530 ± 119 copies/104, (p < 0.001). The expression of BIM, and c-FOS in ATLL patients were higher than HTLV-1 ACs; however, there were no statistically significant differences. The expression of RAD51 as an essential player on DNA repair showed around 160 times increase in ATLL group (166 ± 95) compared to ACs (1.04 ± 0.34) which is statistically significant (p < 0.001). Interestingly, there was a positive correlation between RAD51 expression and HTLV-PVL. The expression of LAT as a central adaptor in TCR signaling interestingly was around 36 times higher in ATLL group than ACs (ATLL; 41.33 ± 19.91 vs. ACs; 1.15 ± 0.22, p < 0.001). This finding showed that TCR signaling pathway mainly provides the growth factors for transformed cells. Furthermore, the overexpression of RAD51 which has been induced in HTLV-1 infected cells as a consequence of virus replication is not able to overcome the DNA damage toward cell transformation.
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Affiliation(s)
- Samaneh Ramezani
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran
| | - Abbas Shirdel
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran.,Hematology and Oncology Department, Ghaem Hospital, Medical School, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Houshang Rafatpanah
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran
| | - Mohammad Mehdi Akbarin
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran
| | - Hanieh Tarokhian
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran
| | - Hossein Rahimi
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran.,Hematology and Oncology Department, Ghaem Hospital, Medical School, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Alireza Bari
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran.,Hematology and Oncology Department, Ghaem Hospital, Medical School, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Hamid Reza Jahantigh
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran
| | - Seyed Abdolrahim Rezaee
- Immunology Research Center, Inflammation and Inflammatory Diseases Division, Medical School, Mashhad University of Medical Sciences, Azadi-Square, Medical Campus, 9177948564, Mashhad, Iran.
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Delabaere L, Ertl HA, Massey DJ, Hofley CM, Sohail F, Bienenstock EJ, Sebastian H, Chiolo I, LaRocque JR. Aging impairs double-strand break repair by homologous recombination in Drosophila germ cells. Aging Cell 2017; 16:320-328. [PMID: 28000382 PMCID: PMC5334535 DOI: 10.1111/acel.12556] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/14/2016] [Indexed: 12/23/2022] Open
Abstract
Aging is characterized by genome instability, which contributes to cancer formation and cell lethality leading to organismal decline. The high levels of DNA double-strand breaks (DSBs) observed in old cells and premature aging syndromes are likely a primary source of genome instability, but the underlying cause of their formation is still unclear. DSBs might result from higher levels of damage or repair defects emerging with advancing age, but repair pathways in old organisms are still poorly understood. Here, we show that premeiotic germline cells of young and old flies have distinct differences in their ability to repair DSBs by the error-free pathway homologous recombination (HR). Repair of DSBs induced by either ionizing radiation (IR) or the endonuclease I-SceI is markedly defective in older flies. This correlates with a remarkable reduction in HR repair measured with the DR-white DSB repair reporter assay. Strikingly, most of this repair defect is already present at 8 days of age. Finally, HR defects correlate with increased expression of early HR components and increased recruitment of Rad51 to damage in older organisms. Thus, we propose that the defect in the HR pathway for germ cells in older flies occurs following Rad51 recruitment. These data reveal that DSB repair defects arise early in the aging process and suggest that HR deficiencies are a leading cause of genome instability in germ cells of older animals.
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Affiliation(s)
- Laetitia Delabaere
- Molecular and Computational Biology Department; University of Southern California; Los Angeles CA 90089 USA
| | - Henry A. Ertl
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
| | - Dashiell J. Massey
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
| | - Carolyn M. Hofley
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
| | - Faraz Sohail
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
| | - Elisa J. Bienenstock
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
- College of Public Service & Community Solutions; Arizona State University; Phoenix AZ 85004 USA
| | - Hans Sebastian
- Molecular and Computational Biology Department; University of Southern California; Los Angeles CA 90089 USA
| | - Irene Chiolo
- Molecular and Computational Biology Department; University of Southern California; Los Angeles CA 90089 USA
| | - Jeannine R. LaRocque
- Department of Human Science; Georgetown University Medical Center; Washington DC 20057 USA
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40
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Amendola PG, Zaghet N, Ramalho JJ, Vilstrup Johansen J, Boxem M, Salcini AE. JMJD-5/KDM8 regulates H3K36me2 and is required for late steps of homologous recombination and genome integrity. PLoS Genet 2017; 13:e1006632. [PMID: 28207814 PMCID: PMC5336306 DOI: 10.1371/journal.pgen.1006632] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 03/03/2017] [Accepted: 02/10/2017] [Indexed: 11/19/2022] Open
Abstract
The eukaryotic genome is organized in a three-dimensional structure called chromatin, constituted by DNA and associated proteins, the majority of which are histones. Post-translational modifications of histone proteins greatly influence chromatin structure and regulate many DNA-based biological processes. Methylation of lysine 36 of histone 3 (H3K36) is a post-translational modification functionally relevant during early steps of DNA damage repair. Here, we show that the JMJD-5 regulates H3K36 di-methylation and it is required at late stages of double strand break repair mediated by homologous recombination. Loss of jmjd-5 results in hypersensitivity to ionizing radiation and in meiotic defects, and it is associated with aberrant retention of RAD-51 at sites of double strand breaks. Analyses of jmjd-5 genetic interactions with genes required for resolving recombination intermediates (rtel-1) or promoting the resolution of RAD-51 double stranded DNA filaments (rfs-1 and helq-1) suggest that jmjd-5 prevents the formation of stalled postsynaptic recombination intermediates and favors RAD-51 removal. As these phenotypes are all recapitulated by a catalytically inactive jmjd-5 mutant, we propose a novel role for H3K36me2 regulation during late steps of homologous recombination critical to preserve genome integrity.
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Affiliation(s)
- Pier Giorgio Amendola
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- Centre for Epigenetics, University of Copenhagen, Copenhagen, Denmark
| | - Nico Zaghet
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- Centre for Epigenetics, University of Copenhagen, Copenhagen, Denmark
| | - João J. Ramalho
- Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, CH Utrecht, The Netherlands
| | - Jens Vilstrup Johansen
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- Centre for Epigenetics, University of Copenhagen, Copenhagen, Denmark
| | - Mike Boxem
- Developmental Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, CH Utrecht, The Netherlands
| | - Anna Elisabetta Salcini
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- Centre for Epigenetics, University of Copenhagen, Copenhagen, Denmark
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Hewitt G, Korolchuk VI. Repair, Reuse, Recycle: The Expanding Role of Autophagy in Genome Maintenance. Trends Cell Biol 2016; 27:340-351. [PMID: 28011061 DOI: 10.1016/j.tcb.2016.11.011] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 11/25/2016] [Accepted: 11/28/2016] [Indexed: 01/01/2023]
Abstract
(Macro)Autophagy is a catabolic pathway that delivers excess, aggregated, or damaged proteins and organelles to lysosomes for degradation. Autophagy is activated in response to numerous cellular stressors such as increased levels of reactive oxygen species (ROS) and low levels of cellular nutrients as well as DNA damage. Although autophagy occurs in the cytoplasm, its inhibition leads to accumulation of DNA damage and genomic instability. In the past few years, our understanding of the interplay between autophagy and genomic stability has greatly increased. In this review we summarize these recent advances in understanding the molecular mechanisms linking autophagy to DNA repair.
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Affiliation(s)
- Graeme Hewitt
- DSB Repair Metabolism Laboratory, The Francis Crick Institute, London NW1 1AT, UK.
| | - Viktor I Korolchuk
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne NE4 5PL, UK.
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42
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Liu DN, Zhou YF, Peng AF, Long XH, Chen XY, Liu ZL, Xia H. HELQ reverses the malignant phenotype of osteosarcoma cells via CHK1-RAD51 signaling pathway. Oncol Rep 2016; 37:1107-1113. [PMID: 28000895 DOI: 10.3892/or.2016.5329] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 11/03/2016] [Indexed: 11/05/2022] Open
Abstract
HELQ is a DNA helicase important for repair of DNA lesions and has been linked to several types of cancer. However, little is known about its relationship with osteosarcoma (OS) and its mechanism. In the present study, the expression of HELQ and its downstream mediators in OS cells was assayed by quantitative PCR and western blot analysis. The function of HELQ in OS cells was investigated by Transwell invasion, wound healing, CCK8 assays and Comet assay. The results demonstrated that HELQ gene and protein were expressed in OS cells. OS cell invasion, migration, proliferation and DNA damage repair were enhanced by HELQ knock-down with shRNA-lentivirus and inhibited by HELQ overexpression with lentivirus transfection. Furthermore, the antitumor activities of HELQ may be associated with upregulated expression of the DNA damage-related proteins CHK1 and RAD51. Our findings indicated that HELQ confers an anti-invasive phenotype on OS cells by activating the CHK1-RAD51 signaling pathway and suggested that HELQ could be recognized as a promising therapeutic target for OS and other types of malignant tumors.
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Affiliation(s)
- Dong Ning Liu
- Southern Medical University, Guangzhou, Guangdong, P.R. China
| | - Yun Fei Zhou
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, P.R. China
| | - Ai Fen Peng
- Jiangxi University of Traditional Chinese Medicine, Nanchang, Jiangxi, P.R. China
| | - Xin Hua Long
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, P.R. China
| | - Xuan Yin Chen
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, P.R. China
| | - Zhi Li Liu
- Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, P.R. China
| | - Hong Xia
- Southern Medical University, Guangzhou, Guangdong, P.R. China
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43
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Li YP, Yang JJ, Xu H, Guo EY, Yu Y. Structure-function analysis of DNA helicase HELQ: A new diagnostic marker in ovarian cancer. Oncol Lett 2016; 12:4439-4444. [PMID: 28101207 PMCID: PMC5228290 DOI: 10.3892/ol.2016.5224] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/09/2016] [Indexed: 01/17/2023] Open
Abstract
It has been previously reported that a deficiency of the helicase, POLQ-like (HELQ) gene increases the risk of ovarian cancer. The present study aimed to explore the structure-function association of HELQ and discuss the effect of molecular structure on the occurrence of tumors. ExPASy tools were employed to analyze the physicochemical properties and secondary structure of the genes. PHYRE2 Protein Fold Recognition Server was used to construct the three-dimensional model and find the ligand-binding sites of HELQ. In addition, the potential functions corresponding to these structures were excavated by comparing and analyzing protein domains. The HELQ protein is located in the cytoplasm (56.5%) and nucleus (21.7%). HELQ has 4 conserved domains, consisting of DEXDc, HELICc, HHH_5 and PRK02362, which contain the adenosine triphosphate (ATP) binding site, nucleotide binding region and putative Mg2+ binding site. In the secondary structure, it was found that HELQ was mainly composed of α helix (46.68%) and random coils (43.05%), with only 10.26% extended strand. According to 3DLigandSite Server, the ligand binding sites appeared in ILE333, LYS335, TYR337, SER362, LEU367, LYS397, GLN340, GLY363, GLY364 and ASN678 of the amino acid sequence. Among the functional protein association networks, regulator of telomere elongation helicase 1, family with sequence similarity 175 member A, small ubiquitin-like modifier 1, DNA polymerase ν and coiled-coil domain containing 158 were involved and co-expressed with HELQ. PredictProtein analysis indicated that the dominant functions of HELQ were ATP-dependent helicase activity and participation in the DNA repair process. Characteristics of the HELQ protein were obtained by bioinformatics analysis, based on which the role of HELQ in DNA replication, DNA repair and maintenance of genomic stability was explored. It was concluded that modulation the function of HELQ helicase may be used in the treatment of ovarian cancer.
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Affiliation(s)
- Ya-Ping Li
- School of Public Health, Health Science Center of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China; Department of Obstetrics and Gynecology, Xi'an Central Hospital, Xi'an, Shaanxi 710003, P.R. China
| | - Jun-Juan Yang
- Department of Obstetrics and Gynecology, Women & Infants Hospital of Zhengzhou, Zhengzhou, Henan 450053, P.R. China
| | - Hui Xu
- Department of Obstetrics and Gynecology, Zhengzhou People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - En-Yu Guo
- Department of Equipment, Zhengzhou People's Hospital, Zhengzhou, Henan 450003, P.R. China
| | - Yan Yu
- School of Public Health, Health Science Center of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
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44
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Martino J, Bernstein KA. The Shu complex is a conserved regulator of homologous recombination. FEMS Yeast Res 2016; 16:fow073. [PMID: 27589940 DOI: 10.1093/femsyr/fow073] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2016] [Indexed: 02/06/2023] Open
Abstract
Homologous recombination (HR) is an error-free DNA repair mechanism that maintains genome integrity by repairing double-strand breaks (DSBs). Defects in HR lead to genomic instability and are associated with cancer predisposition. A key step in HR is the formation of Rad51 nucleoprotein filaments which are responsible for the homology search and strand invasion steps that define HR. Recently, the budding yeast Shu complex has emerged as an important regulator of Rad51 along with the other Rad51 mediators including Rad52 and the Rad51 paralogs, Rad55-Rad57. The Shu complex is a heterotetramer consisting of two novel Rad51 paralogs, Psy3 and Csm2, along with Shu1 and a SWIM domain-containing protein, Shu2. Studies done primarily in yeast have provided evidence that the Shu complex regulates HR at several types of DNA DSBs (i.e. replication-associated and meiotic DSBs) and that its role in HR is highly conserved across eukaryotic lineages. This review highlights the main findings of these studies and discusses the proposed specific roles of the Shu complex in many aspects of recombination-mediated DNA repair.
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Affiliation(s)
- Julieta Martino
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine and University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213, USA
| | - Kara A Bernstein
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine and University of Pittsburgh Cancer Institute, Pittsburgh, PA 15213, USA
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45
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Remodeling and Control of Homologous Recombination by DNA Helicases and Translocases that Target Recombinases and Synapsis. Genes (Basel) 2016; 7:genes7080052. [PMID: 27548227 PMCID: PMC4999840 DOI: 10.3390/genes7080052] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/24/2016] [Accepted: 08/12/2016] [Indexed: 11/16/2022] Open
Abstract
Recombinase enzymes catalyse invasion of single-stranded DNA (ssDNA) into homologous duplex DNA forming "Displacement loops" (D-loops), a process called synapsis. This triggers homologous recombination (HR), which can follow several possible paths to underpin DNA repair and restart of blocked and collapsed DNA replication forks. Therefore, synapsis can be a checkpoint for controlling whether or not, how far, and by which pathway, HR proceeds to overcome an obstacle or break in a replication fork. Synapsis can be antagonized by limiting access of a recombinase to ssDNA and by dissociation of D-loops or heteroduplex formed by synapsis. Antagonists include DNA helicases and translocases that are identifiable in eukaryotes, bacteria and archaea, and which target synaptic and pre-synaptic DNA structures thereby controlling HR at early stages. Here we survey these events with emphasis on enabling DNA replication to be resumed from sites of blockage or collapse. We also note how knowledge of anti-recombination activities could be useful to improve efficiency of CRISPR-based genome editing.
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46
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Godin SK, Sullivan MR, Bernstein KA. Novel insights into RAD51 activity and regulation during homologous recombination and DNA replication. Biochem Cell Biol 2016; 94:407-418. [PMID: 27224545 DOI: 10.1139/bcb-2016-0012] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In this review we focus on new insights that challenge our understanding of homologous recombination (HR) and Rad51 regulation. Recent advances using high-resolution microscopy and single molecule techniques have broadened our knowledge of Rad51 filament formation and strand invasion at double-strand break (DSB) sites and at replication forks, which are one of most physiologically relevant forms of HR from yeast to humans. Rad51 filament formation and strand invasion is regulated by many mediator proteins such as the Rad51 paralogues and the Shu complex, consisting of a Shu2/SWS1 family member and additional Rad51 paralogues. Importantly, a novel RAD51 paralogue was discovered in Caenorhabditis elegans, and its in vitro characterization has demonstrated a new function for the worm RAD51 paralogues during HR. Conservation of the human RAD51 paralogues function during HR and repair of replicative damage demonstrate how the RAD51 mediators play a critical role in human health and genomic integrity. Together, these new findings provide a framework for understanding RAD51 and its mediators in DNA repair during multiple cellular contexts.
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Affiliation(s)
- Stephen K Godin
- University of Pittsburgh School of Medicine, University of Pittsburgh Cancer Institute, and the Department of Microbiology and Molecular Genetics.,University of Pittsburgh School of Medicine, University of Pittsburgh Cancer Institute, and the Department of Microbiology and Molecular Genetics
| | - Meghan R Sullivan
- University of Pittsburgh School of Medicine, University of Pittsburgh Cancer Institute, and the Department of Microbiology and Molecular Genetics.,University of Pittsburgh School of Medicine, University of Pittsburgh Cancer Institute, and the Department of Microbiology and Molecular Genetics
| | - Kara A Bernstein
- University of Pittsburgh School of Medicine, University of Pittsburgh Cancer Institute, and the Department of Microbiology and Molecular Genetics
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47
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Meiotic recombination and the crossover assurance checkpoint in Caenorhabditis elegans. Semin Cell Dev Biol 2016; 54:106-16. [PMID: 27013114 DOI: 10.1016/j.semcdb.2016.03.014] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 03/16/2016] [Indexed: 12/13/2022]
Abstract
During meiotic prophase, chromosomes pair and synapse with their homologs and undergo programmed DNA double-strand break (DSB) formation to initiate meiotic recombination. These DSBs are processed to generate a limited number of crossover recombination products on each chromosome, which are essential to ensure faithful segregation of homologous chromosomes. The nematode Caenorhabditis elegans has served as an excellent model organism to investigate the mechanisms that drive and coordinate these chromosome dynamics during meiosis. Here we focus on our current understanding of the regulation of DSB induction in C. elegans. We also review evidence that feedback regulation of crossover formation prolongs the early stages of meiotic prophase, and discuss evidence that this can alter the recombination pattern, most likely by shifting the genome-wide distribution of DSBs.
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48
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Promotion of Homologous Recombination by SWS-1 in Complex with RAD-51 Paralogs in Caenorhabditis elegans. Genetics 2016; 203:133-45. [PMID: 26936927 DOI: 10.1534/genetics.115.185827] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 02/19/2016] [Indexed: 11/18/2022] Open
Abstract
Homologous recombination (HR) repairs cytotoxic DNA double-strand breaks (DSBs) with high fidelity. Deficiencies in HR result in genome instability. A key early step in HR is the search for and invasion of a homologous DNA template by a single-stranded RAD-51 nucleoprotein filament. The Shu complex, composed of a SWIM domain-containing protein and its interacting RAD51 paralogs, promotes HR by regulating RAD51 filament dynamics. Despite Shu complex orthologs throughout eukaryotes, our understanding of its function has been most extensively characterized in budding yeast. Evolutionary analysis of the SWIM domain identified Caenorhabditis elegans sws-1 as a putative homolog of the yeast Shu complex member Shu2. Using a CRISPR-induced nonsense allele of sws-1, we show that sws-1 promotes HR in mitotic and meiotic nuclei. sws-1 mutants exhibit sensitivity to DSB-inducing agents and fail to form mitotic RAD-51 foci following treatment with camptothecin. Phenotypic similarities between sws-1 and the two RAD-51 paralogs rfs-1 and rip-1 suggest that they function together. Indeed, we detect direct interaction between SWS-1 and RIP-1 by yeast two-hybrid assay that is mediated by the SWIM domain in SWS-1 and the Walker B motif in RIP-1 Furthermore, RIP-1 bridges an interaction between SWS-1 and RFS-1, suggesting that RIP-1 facilitates complex formation with SWS-1 and RFS-1 We propose that SWS-1, RIP-1, and RFS-1 compose a C. elegans Shu complex. Our work provides a new model for studying Shu complex disruption in the context of a multicellular organism that has important implications as to why mutations in the human RAD51 paralogs are associated with genome instability.
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49
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Ceccaldi R, Rondinelli B, D'Andrea AD. Repair Pathway Choices and Consequences at the Double-Strand Break. Trends Cell Biol 2015; 26:52-64. [PMID: 26437586 DOI: 10.1016/j.tcb.2015.07.009] [Citation(s) in RCA: 1004] [Impact Index Per Article: 111.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 07/16/2015] [Accepted: 07/29/2015] [Indexed: 02/03/2023]
Abstract
DNA double-strand breaks (DSBs) are cytotoxic lesions that threaten genomic integrity. Failure to repair a DSB has deleterious consequences, including genomic instability and cell death. Indeed, misrepair of DSBs can lead to inappropriate end-joining events, which commonly underlie oncogenic transformation due to chromosomal translocations. Typically, cells employ two main mechanisms to repair DSBs: homologous recombination (HR) and classical nonhomologous end joining (C-NHEJ). In addition, alternative error-prone DSB repair pathways, namely alternative end joining (alt-EJ) and single-strand annealing (SSA), have been recently shown to operate in many different conditions and to contribute to genome rearrangements and oncogenic transformation. Here, we review the mechanisms regulating DSB repair pathway choice, together with the potential interconnections between HR and the annealing-dependent error-prone DSB repair pathways.
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Affiliation(s)
- Raphael Ceccaldi
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Beatrice Rondinelli
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - Alan D D'Andrea
- Department of Radiation Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.
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50
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Chung G, Rose AM, Petalcorin MIR, Martin JS, Kessler Z, Sanchez-Pulido L, Ponting CP, Yanowitz JL, Boulton SJ. REC-1 and HIM-5 distribute meiotic crossovers and function redundantly in meiotic double-strand break formation in Caenorhabditis elegans. Genes Dev 2015; 29:1969-79. [PMID: 26385965 PMCID: PMC4579353 DOI: 10.1101/gad.266056.115] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/26/2015] [Indexed: 01/07/2023]
Abstract
The Caenorhabditis elegans gene rec-1 was the first genetic locus identified in metazoa to affect the distribution of meiotic crossovers along the chromosome. We report that rec-1 encodes a distant paralog of HIM-5, which was discovered by whole-genome sequencing and confirmed by multiple genome-edited alleles. REC-1 is phosphorylated by cyclin-dependent kinase (CDK) in vitro, and mutation of the CDK consensus sites in REC-1 compromises meiotic crossover distribution in vivo. Unexpectedly, rec-1; him-5 double mutants are synthetic-lethal due to a defect in meiotic double-strand break formation. Thus, we uncovered an unexpected robustness to meiotic DSB formation and crossover positioning that is executed by HIM-5 and REC-1 and regulated by phosphorylation.
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Affiliation(s)
- George Chung
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Ann M Rose
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Mark I R Petalcorin
- DNA Damage Response Laboratory, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom; Clare Hall Laboratories, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom
| | - Julie S Martin
- DNA Damage Response Laboratory, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom; Clare Hall Laboratories, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom
| | - Zebulin Kessler
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA
| | - Luis Sanchez-Pulido
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Chris P Ponting
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Judith L Yanowitz
- Magee-Womens Research Institute, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA
| | - Simon J Boulton
- DNA Damage Response Laboratory, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom; Clare Hall Laboratories, The Francis Crick Institute, South Mimms EN3 3LD, United Kingdom
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