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Akita M, Girvan P, Spirek M, Novacek J, Rueda D, Prokop Z, Krejci L. Mechanism of BCDX2-mediated RAD51 nucleation on short ssDNA stretches and fork DNA. Nucleic Acids Res 2024:gkae770. [PMID: 39268578 DOI: 10.1093/nar/gkae770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 08/20/2024] [Accepted: 08/26/2024] [Indexed: 09/17/2024] Open
Abstract
Homologous recombination (HR) factors are crucial for DSB repair and processing stalled replication forks. RAD51 paralogs, including RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3, have emerged as essential tumour suppressors, forming two subcomplexes, BCDX2 and CX3. Mutations in these genes are associated with cancer susceptibility and Fanconi anaemia, yet their biochemical activities remain unclear. This study reveals a linear arrangement of BCDX2 subunits compared to the RAD51 ring. BCDX2 shows a strong affinity towards single-stranded DNA (ssDNA) via unique binding mechanism compared to RAD51, and a contribution of DX2 subunits in binding branched DNA substrates. We demonstrate that BCDX2 facilitates RAD51 loading on ssDNA by suppressing the cooperative requirement of RAD51 binding to DNA and stabilizing the filament. Notably, BCDX2 also promotes RAD51 loading on short ssDNA and reversed replication fork substrates. Moreover, while mutants defective in ssDNA binding retain the ability to bind branched DNA substrates, they still facilitate RAD51 loading onto reversed replication forks. Our study provides mechanistic insights into how the BCDX2 complex stimulates the formation of BRCA2-independent RAD51 filaments on short stretches of ssDNA present at ssDNA gaps or stalled replication forks, highlighting its role in genome maintenance and DNA repair.
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Affiliation(s)
- Masaki Akita
- Department of Biology and National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic
| | - Paul Girvan
- Department of Infectious Disease, Faculty of Medicine, Imperial College London, London, UK
| | - Mario Spirek
- Department of Biology and National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic
| | - Jiri Novacek
- Cryo-Electron Microscopy and Tomography Core Facility, Central European Institute of Technology, Brno, Czech Republic
| | - David 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
| | - Zbynek Prokop
- Loschmidt Laboratories, Department of Experimental Biology and RECETOX, Faculty of Science, Masaryk University, Brno, Czech Republic
- International Clinical Research Center, St Anne's University Hospital, Brno, Czech Republic
| | - Lumir Krejci
- Department of Biology and National Centre for Biomolecular Research, Masaryk University, Brno, Czech Republic
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2
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Hengel SR, Oppenheimer KG, Smith CM, Schaich MA, Rein HL, Martino J, Darrah KE, Witham M, Ezekwenna OC, Burton KR, Van Houten B, Spies M, Bernstein KA. The human Shu complex promotes RAD51 activity by modulating RPA dynamics on ssDNA. Nat Commun 2024; 15:7197. [PMID: 39169038 PMCID: PMC11339404 DOI: 10.1038/s41467-024-51595-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 08/09/2024] [Indexed: 08/23/2024] Open
Abstract
Templated DNA repair that occurs during homologous recombination and replication stress relies on RAD51. RAD51 activity is positively regulated by BRCA2 and the RAD51 paralogs. The Shu complex is a RAD51 paralog-containing complex consisting of SWSAP1, SWS1, and SPIDR. We demonstrate that SWSAP1-SWS1 binds RAD51, maintains RAD51 filament stability, and enables strand exchange. Using single-molecule confocal fluorescence microscopy combined with optical tweezers, we show that SWSAP1-SWS1 decorates RAD51 filaments proficient for homologous recombination. We also find SWSAP1-SWS1 enhances RPA diffusion on ssDNA. Importantly, we show human sgSWSAP1 and sgSWS1 knockout cells are sensitive to pharmacological inhibition of PARP and APE1. Lastly, we identify cancer variants in SWSAP1 that alter Shu complex formation. Together, we show that SWSAP1-SWS1 stimulates RAD51-dependent high-fidelity repair and may be an important new cancer therapeutic target.
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Affiliation(s)
- Sarah R Hengel
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA.
- Tufts University, Department of Biology, Medford, MA, USA.
| | - Katherine G Oppenheimer
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
| | - Chelsea M Smith
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
- University of North Carolina at Chapel Hill, Department of Pathology and Laboratory Medicine, Chapel Hill, NC, USA
| | - Matthew A Schaich
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
| | - Hayley L Rein
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
| | - Julieta Martino
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
- GeneDx, Gaithersburg, MD, USA
| | - Kristie E Darrah
- University of Pennsylvania School of Medicine, Penn Center for Genome Integrity, Department of Biochemistry and Biophysics, 421 Curie Boulevard, Philadelphia, PA, USA
| | - Maggie Witham
- Tufts University, Department of Biology, Medford, MA, USA
| | | | - Kyle R Burton
- Tufts University, Department of Biology, Medford, MA, USA
| | - Bennett Van Houten
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA
| | - Maria Spies
- University of Iowa, Department of Biochemistry and Molecular Biology, Iowa City, IA, USA
| | - Kara A Bernstein
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, UPMC-Hillman Cancer Center, Pittsburgh, PA, USA.
- University of Pennsylvania School of Medicine, Penn Center for Genome Integrity, Department of Biochemistry and Biophysics, 421 Curie Boulevard, Philadelphia, PA, USA.
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3
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Kwong A, Ho CYS, Au CH, Tey SK, Ma ESK. Germline RAD51C and RAD51D Mutations in High-Risk Chinese Breast and/or Ovarian Cancer Patients and Families. J Pers Med 2024; 14:866. [PMID: 39202057 PMCID: PMC11355318 DOI: 10.3390/jpm14080866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2024] [Revised: 08/05/2024] [Accepted: 08/14/2024] [Indexed: 09/03/2024] Open
Abstract
BACKGROUND RAD51C and RAD51D are crucial in homologous recombination (HR) DNA repair. The prevalence of the RAD51C and RAD51D mutations in breast cancer varies across ethnic groups. Associations of RAD51C and RAD51D germline pathogenic variants (GPVs) with breast and ovarian cancer predisposition have been recently reported and are of interest. METHODS We performed multi-gene panel sequencing to study the prevalence of RAD51C and RAD51D germline mutations among 3728 patients with hereditary breast and/or ovarian cancer (HBOC). RESULTS We identified 18 pathogenic RAD51C and RAD51D mutation carriers, with a mutation frequency of 0.13% (5/3728) and 0.35% (13/3728), respectively. The most common recurrent mutation was RAD51D c.270_271dupTA; p.(Lys91Ilefs*13), with a mutation frequency of 0.30% (11/3728), which was also commonly identified in Asians. Only four out of six cases (66.7%) of this common mutation tested positive for homologous recombination deficiency (HRD). CONCLUSIONS Taking the family studies in our registry and tumor molecular pathology together, we concluded that this relatively common RAD51D variant showed incomplete penetrance in our local Chinese community. Personalized genetic counseling emphasizing family history for families with this variant, as suggested at the UK Cancer Genetics Group (UKCGG) Consensus meeting, would also be appropriate in Chinese families.
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Affiliation(s)
- Ava Kwong
- Division of Breast Surgery, Department of Surgery, The University of Hong Kong, Hong Kong SAR, China
- Hong Kong Hereditary Breast Cancer Family Registry, Hong Kong SAR, China
- Cancer Genetics Centre, Breast Surgery Centre, Surgery Centre, Hong Kong Sanatorium & Hospital, Hong Kong SAR, China
| | - Cecilia Yuen Sze Ho
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Hong Kong SAR, China
| | - Chun Hang Au
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Hong Kong SAR, China
| | - Sze Keong Tey
- Division of Breast Surgery, Department of Surgery, The University of Hong Kong, Hong Kong SAR, China
| | - Edmond Shiu Kwan Ma
- Hong Kong Hereditary Breast Cancer Family Registry, Hong Kong SAR, China
- Division of Molecular Pathology, Department of Pathology, Hong Kong Sanatorium & Hospital, Hong Kong SAR, China
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4
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Németh E, Szüts D. The mutagenic consequences of defective DNA repair. DNA Repair (Amst) 2024; 139:103694. [PMID: 38788323 DOI: 10.1016/j.dnarep.2024.103694] [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: 03/22/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 05/26/2024]
Abstract
Multiple separate repair mechanisms safeguard the genome against various types of DNA damage, and their failure can increase the rate of spontaneous mutagenesis. The malfunction of distinct repair mechanisms leads to genomic instability through different mutagenic processes. For example, defective mismatch repair causes high base substitution rates and microsatellite instability, whereas homologous recombination deficiency is characteristically associated with deletions and chromosome instability. This review presents a comprehensive collection of all mutagenic phenotypes associated with the loss of each DNA repair mechanism, drawing on data from a variety of model organisms and mutagenesis assays, and placing greatest emphasis on systematic analyses of human cancer datasets. We describe the latest theories on the mechanism of each mutagenic process, often explained by reliance on an alternative repair pathway or the error-prone replication of unrepaired, damaged DNA. Aided by the concept of mutational signatures, the genomic phenotypes can be used in cancer diagnosis to identify defective DNA repair pathways.
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Affiliation(s)
- Eszter Németh
- Institute of Molecular Life Sciences, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary
| | - Dávid Szüts
- Institute of Molecular Life Sciences, HUN-REN Research Centre for Natural Sciences, Budapest, Hungary.
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5
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Feng Z, Chen S, An N, Xiu Z, Ju X, Chen X, Bi R, Wang J, Zhu S, Wu X, Wen H. Germline Mutational Landscape and Novel Targetable RAD51D Variant in Chinese Patients With Ovarian Cancer. JCO Glob Oncol 2024; 10:e2300454. [PMID: 38905575 DOI: 10.1200/go.23.00454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 04/02/2024] [Accepted: 05/03/2024] [Indexed: 06/23/2024] Open
Abstract
PURPOSE Genetic variants of ovarian cancer (OV) show ethnic differences, but data from the Chinese population are still insufficient. Here, we elucidate the inheritance landscape in Chinese patients with OV and examine the functional implications of a Chinese-enriched RAD51D variant. METHODS Between 2015 and 2018, 373 consecutive patients with OV were prospectively enrolled. Variants of BRCA1/2, other homologous recombination repair (HRR) genes, and DNA mismatch repair (MMR) genes were analyzed using next-generation sequencing. An enriched RAD51D variant was identified, and its functional effects were examined using Cell Counting Kit-8, colony formation, transwell migration, and drug sensitivity assays. RESULTS Overall, 31.1% (116/373) of patients had at least one pathogenic or likely pathogenic germline variant. BRCA1 and BRCA2 accounted for 16.09% and 5.36%, respectively, with one patient having both variants. In addition, 32 (8.58%) patients carried other HRR gene variants, whereas three (0.8%) patients had MMR gene variants. The RAD51D variant ranked third (8/373, 2.1%), and its rate was much higher than that in other populations. Remarkably, all eight patients harbored the RAD51D K91fs variant (c.270_271dup, p.Lys91Ilefs*13) and demonstrated satisfactory platinum response and favorable prognosis. This variant confers enhanced sensitivity to poly (ADP-ribose) polymerase inhibitors in OV cells. However, the effects on platinum sensitivity were inconsistent across different cell lines. Against the background of the TP53 variant, RAD51D K91fs variant showed increased sensitivity to cisplatin. CONCLUSION Our study revealed the inheritance landscape of OV and identified an enriched RAD51D variant in Chinese patients with OV. This can serve as an important reference for OV management and a potential therapeutic target.
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Affiliation(s)
- Zheng Feng
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Siyu Chen
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Na An
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | - Zhihui Xiu
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | - Xingzhu Ju
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xiaojun Chen
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Rui Bi
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
- Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, China
| | - Jie Wang
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | - Shida Zhu
- BGI Genomics, BGI-Shenzhen, Shenzhen, China
| | - Xiaohua Wu
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Hao Wen
- Department of Gynecological Oncology, Fudan University Shanghai Cancer Center, Shanghai, China
- Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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6
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Barua D, Płecha M, Muszewska A. A minimal Fanconi Anemia complex in early diverging fungi. Sci Rep 2024; 14:9922. [PMID: 38688950 PMCID: PMC11061109 DOI: 10.1038/s41598-024-60318-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 04/22/2024] [Indexed: 05/02/2024] Open
Abstract
Fanconi Anemia (FA) pathway resolves DNA interstrand cross links (ICL). The FA pathway was initially recognized in vertebrates, but was later confirmed in other animals and speculated in fungi. FA proteins FANCM, FANCL and FANCJ are present in Saccharomyces cerevisiae but, their mechanism of interaction to resolve ICL is still unclear. Unlike Dikarya, early diverging fungi (EDF) possess more traits shared with animals. We traced the evolutionary history of the FA pathway across Opisthokonta. We scanned complete proteomes for FA-related homologs to establish their taxonomic distribution and analyzed their phylogenetic trees. We checked transcription profiles of FA genes to test if they respond to environmental conditions and their genomic localizations for potential co-localization. We identified fungal homologs of the activation and ID complexes, 5 out of 8 core proteins, all of the endonucleases, and deubiquitination proteins. All fungi lack FANCC, FANCF and FANCG proteins responsible for post-replication repair and chromosome stability in animals. The observed taxonomic distribution can be attributed to a gradual degradation of the FA pathway from EDF to Dikarya. One of the key differences is that EDF have the ID complex recruiting endonucleases to the site of ICL. Moreover, 21 out of 32 identified FA genes are upregulated in response to different growth conditions. Several FA genes are co-localized in fungal genomes which also could facilitate co-expression. Our results indicate that a minimal FA pathway might still be functional in Mucoromycota with a gradual loss of components in Dikarya ancestors.
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Affiliation(s)
- Drishtee Barua
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland
| | - Magdalena Płecha
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland
| | - Anna Muszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5A, 02-106, Warsaw, Poland.
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7
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Hu J, Crickard JB. All who wander are not lost: the search for homology during homologous recombination. Biochem Soc Trans 2024; 52:367-377. [PMID: 38323621 PMCID: PMC10903458 DOI: 10.1042/bst20230705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/10/2024] [Accepted: 01/12/2024] [Indexed: 02/08/2024]
Abstract
Homologous recombination (HR) is a template-based DNA double-strand break repair pathway that functions to maintain genomic integrity. A vital component of the HR reaction is the identification of template DNA to be used during repair. This occurs through a mechanism known as the homology search. The homology search occurs in two steps: a collision step in which two pieces of DNA are forced to collide and a selection step that results in homologous pairing between matching DNA sequences. Selection of a homologous template is facilitated by recombinases of the RecA/Rad51 family of proteins in cooperation with helicases, translocases, and topoisomerases that determine the overall fidelity of the match. This menagerie of molecular machines acts to regulate critical intermediates during the homology search. These intermediates include recombinase filaments that probe for short stretches of homology and early strand invasion intermediates in the form of displacement loops (D-loops) that stabilize paired DNA. Here, we will discuss recent advances in understanding how these specific intermediates are regulated on the molecular level during the HR reaction. We will also discuss how the stability of these intermediates influences the ultimate outcomes of the HR reaction. Finally, we will discuss recent physiological models developed to explain how the homology search protects the genome.
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Affiliation(s)
- Jingyi Hu
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, U.S.A
| | - J. Brooks Crickard
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, U.S.A
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8
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Hengel SR, Oppenheimer K, Smith C, Schaich MA, Rein HL, Martino J, Darrah K, Ezekwenna O, Burton K, Van Houten B, Spies M, Bernstein KA. The human Shu complex promotes RAD51 activity by modulating RPA dynamics on ssDNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.14.580393. [PMID: 38405734 PMCID: PMC10888808 DOI: 10.1101/2024.02.14.580393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Templated DNA repair that occurs during homologous recombination and replication stress relies on RAD51. RAD51 activity is positively regulated by BRCA2 and the RAD51 paralogs. The Shu complex is a RAD51 paralog-containing complex consisting of SWSAP1 and SWS1. We demonstrate that SWSAP1-SWS1 binds RAD51, maintains RAD51 filament stability, and enables strand exchange. Using single molecule confocal fluorescence microscopy combined with optical tweezers, we show that SWSAP1-SWS1 decorates RAD51 filaments proficient for homologous recombination. We also find SWSAP1-SWS1 enhances RPA diffusion on ssDNA. Importantly, we show human sgSWSAP1 and sgSWS1 knockout cells are sensitive to pharmacological inhibition of PARP and APE1. Lastly, we identify cancer variants in SWSAP1 that alter SWS1 complex formation. Together, we show that SWSAP1-SWS1 stimulates RAD51-dependent high-fidelity repair and may be an important new cancer therapeutic target.
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9
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Guh CL, Lei KH, Chen YA, Jiang YZ, Chang HY, Liaw H, Li HW, Yen HY, Chi P. RAD51 paralogs synergize with RAD51 to protect reversed forks from cellular nucleases. Nucleic Acids Res 2023; 51:11717-11731. [PMID: 37843130 PMCID: PMC10681713 DOI: 10.1093/nar/gkad856] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 09/12/2023] [Accepted: 09/23/2023] [Indexed: 10/17/2023] Open
Abstract
Fork reversal is a conserved mechanism to prevent stalled replication forks from collapsing. Formation and protection of reversed forks are two crucial steps in ensuring fork integrity and stability. Five RAD51 paralogs, namely, RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3, which share sequence and structural similarity to the recombinase RAD51, play poorly defined mechanistic roles in these processes. Here, using purified BCDX2 (RAD51BCD-XRCC2) and CX3 (RAD51C-XRCC3) complexes and in vitro reconstituted biochemical systems, we mechanistically dissect their functions in forming and protecting reversed forks. We show that both RAD51 paralog complexes lack fork reversal activities. Whereas CX3 exhibits modest fork protection activity, BCDX2 significantly synergizes with RAD51 to protect DNA against attack by the nucleases MRE11 and EXO1. DNA protection is contingent upon the ability of RAD51 to form a functional nucleoprotein filament on DNA. Collectively, our results provide evidence for a hitherto unknown function of RAD51 paralogs in synergizing with RAD51 nucleoprotein filament to prevent degradation of stressed replication forks.
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Affiliation(s)
- Chia-Lun Guh
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Kai-Hang Lei
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Yi-An Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Yi-Zhen Jiang
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Hao-Yen Chang
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | - Hungjiun Liaw
- Department of Life Sciences, National Cheng Kung University, Tainan, Taiwan
| | - Hung-Wen Li
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | - Hsin-Yung Yen
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Peter Chi
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
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10
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Ito M, Furukohri A, Matsuzaki K, Fujita Y, Toyoda A, Shinohara A. FIGNL1 AAA+ ATPase remodels RAD51 and DMC1 filaments in pre-meiotic DNA replication and meiotic recombination. Nat Commun 2023; 14:6857. [PMID: 37891173 PMCID: PMC10611733 DOI: 10.1038/s41467-023-42576-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 10/16/2023] [Indexed: 10/29/2023] Open
Abstract
The formation of RAD51/DMC1 filaments on single-stranded (ss)DNAs essential for homology search and strand exchange in DNA double-strand break (DSB) repair is tightly regulated. FIGNL1 AAA+++ ATPase controls RAD51-mediated recombination in human cells. However, its role in gametogenesis remains unsolved. Here, we characterized a germ line-specific conditional knockout (cKO) mouse of FIGNL1. Fignl1 cKO male mice showed defective chromosome synapsis and impaired meiotic DSB repair with the accumulation of RAD51/DMC1 on meiotic chromosomes, supporting a positive role of FIGNL1 in homologous recombination at a post-assembly stage of RAD51/DMC1 filaments. Fignl1 cKO spermatocytes also accumulate RAD51/DMC1 on chromosomes in pre-meiotic S-phase. These RAD51/DMC1 assemblies are independent of meiotic DSB formation. We also showed that purified FIGNL1 dismantles RAD51 filament on double-stranded (ds)DNA as well as ssDNA. These results suggest an additional role of FIGNL1 in limiting the non-productive assembly of RAD51/DMC1 on native dsDNAs during pre-meiotic S-phase and meiotic prophase I.
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Affiliation(s)
- Masaru Ito
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan.
| | - Asako Furukohri
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Kenichiro Matsuzaki
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
- Department of Advanced Bioscience, Graduate School of Agriculture, Kindai University, Nara, Nara, 631-8505, Japan
| | - Yurika Fujita
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Atsushi Toyoda
- Advanced Genomics Center, National Institute of Genetics, Mishima, Shizuoka, 411-8540, Japan
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan.
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11
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Mladenov E, Mladenova V, Stuschke M, Iliakis G. New Facets of DNA Double Strand Break Repair: Radiation Dose as Key Determinant of HR versus c-NHEJ Engagement. Int J Mol Sci 2023; 24:14956. [PMID: 37834403 PMCID: PMC10573367 DOI: 10.3390/ijms241914956] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/01/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023] Open
Abstract
Radiation therapy is an essential component of present-day cancer management, utilizing ionizing radiation (IR) of different modalities to mitigate cancer progression. IR functions by generating ionizations in cells that induce a plethora of DNA lesions. The most detrimental among them are the DNA double strand breaks (DSBs). In the course of evolution, cells of higher eukaryotes have evolved four major DSB repair pathways: classical non-homologous end joining (c-NHEJ), homologous recombination (HR), alternative end-joining (alt-EJ), and single strand annealing (SSA). These mechanistically distinct repair pathways have different cell cycle- and homology-dependencies but, surprisingly, they operate with widely different fidelity and kinetics and therefore contribute unequally to cell survival and genome maintenance. It is therefore reasonable to anticipate tight regulation and coordination in the engagement of these DSB repair pathway to achieve the maximum possible genomic stability. Here, we provide a state-of-the-art review of the accumulated knowledge on the molecular mechanisms underpinning these repair pathways, with emphasis on c-NHEJ and HR. We discuss factors and processes that have recently come to the fore. We outline mechanisms steering DSB repair pathway choice throughout the cell cycle, and highlight the critical role of DNA end resection in this process. Most importantly, however, we point out the strong preference for HR at low DSB loads, and thus low IR doses, for cells irradiated in the G2-phase of the cell cycle. We further explore the molecular underpinnings of transitions from high fidelity to low fidelity error-prone repair pathways and analyze the coordination and consequences of this transition on cell viability and genomic stability. Finally, we elaborate on how these advances may help in the development of improved cancer treatment protocols in radiation therapy.
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Affiliation(s)
- Emil Mladenov
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (V.M.); (M.S.)
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany
| | - Veronika Mladenova
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (V.M.); (M.S.)
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany
| | - Martin Stuschke
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (V.M.); (M.S.)
- German Cancer Consortium (DKTK), Partner Site University Hospital Essen, 45147 Essen, Germany
- German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - George Iliakis
- Division of Experimental Radiation Biology, Department of Radiation Therapy, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (V.M.); (M.S.)
- Institute of Medical Radiation Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany
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12
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Szakal B, Branzei D. Hot on RAD51C: structure and functions of RAD51C-XRCC3. Mol Oncol 2023; 17:1950-1952. [PMID: 37681281 PMCID: PMC10552886 DOI: 10.1002/1878-0261.13518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/04/2023] [Accepted: 09/05/2023] [Indexed: 09/09/2023] Open
Abstract
A new study by Longo, Roy et al. has solved the structure of the RAD51C-XRCC3 (CX3) heterodimer with a bound ATP analog, identifying two main structural interfaces and defining separable replication fork stability roles. One function relates to the ability of RAD51C to bind and assemble CX3 on nascent DNA, with an impact on the ability of forks to restart upon replication stress. The other relates to effective CX3 heterodimer formation, required for 5' RAD51 filament capping, with effects on RAD51 filament disassembly, fork protection and influencing the persistence of reversed forks.
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Affiliation(s)
- Barnabas Szakal
- IFOM ETS, The AIRC Institute of Molecular OncologyMilanItaly
| | - Dana Branzei
- IFOM ETS, The AIRC Institute of Molecular OncologyMilanItaly
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM‐CNR)PaviaItaly
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13
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Rein HL, Bernstein KA. Finding significance: New perspectives in variant classification of the RAD51 regulators, BRCA2 and beyond. DNA Repair (Amst) 2023; 130:103563. [PMID: 37651978 PMCID: PMC10529980 DOI: 10.1016/j.dnarep.2023.103563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/11/2023] [Accepted: 08/15/2023] [Indexed: 09/02/2023]
Abstract
For many individuals harboring a variant of uncertain functional significance (VUS) in a homologous recombination (HR) gene, their risk of developing breast and ovarian cancer is unknown. Integral to the process of HR are BRCA1 and regulators of the central HR protein, RAD51, including BRCA2, PALB2, RAD51C and RAD51D. Due to advancements in sequencing technology and the continued expansion of cancer screening panels, the number of VUS identified in these genes has risen significantly. Standard practices for variant classification utilize different types of predictive, population, phenotypic, allelic and functional evidence. While variant analysis is improving, there remains a struggle to keep up with demand. Understanding the effects of an HR variant can aid in preventative care and is critical for developing an effective cancer treatment plan. In this review, we discuss current perspectives in the classification of variants in the breast and ovarian cancer genes BRCA1, BRCA2, PALB2, RAD51C and RAD51D.
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Affiliation(s)
- Hayley L Rein
- University of Pittsburgh, School of Medicine, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, USA
| | - Kara A Bernstein
- University of Pennsylvania School of Medicine, Department of Biochemistry and Biophysics, 421 Curie Boulevard, Philadelphia, PA, USA.
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14
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Simpson D, Ling J, Jing Y, Adamson B. Mapping the Genetic Interaction Network of PARP inhibitor Response. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.19.553986. [PMID: 37645833 PMCID: PMC10462155 DOI: 10.1101/2023.08.19.553986] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Genetic interactions have long informed our understanding of the coordinated proteins and pathways that respond to DNA damage in mammalian cells, but systematic interrogation of the genetic network underlying that system has yet to be achieved. Towards this goal, we measured 147,153 pairwise interactions among genes implicated in PARP inhibitor (PARPi) response. Evaluating genetic interactions at this scale, with and without exposure to PARPi, revealed hierarchical organization of the pathways and complexes that maintain genome stability during normal growth and defined changes that occur upon accumulation of DNA lesions due to cytotoxic doses of PARPi. We uncovered unexpected relationships among DNA repair genes, including context-specific buffering interactions between the minimally characterized AUNIP and BRCA1-A complex genes. Our work thus establishes a foundation for mapping differential genetic interactions in mammalian cells and provides a comprehensive resource for future studies of DNA repair and PARP inhibitors.
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Affiliation(s)
- Danny Simpson
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Jia Ling
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Yangwode Jing
- Department of Chemistry, Princeton University, Princeton, NJ 08544, USA
| | - Britt Adamson
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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15
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Hu C, Nagaraj AB, Shimelis H, Montalban G, Lee KY, Huang H, Lumby CA, Na J, Susswein LR, Roberts ME, Marshall ML, Hiraki S, LaDuca H, Chao E, Yussuf A, Pesaran T, Neuhausen SL, Haiman CA, Kraft P, Lindstrom S, Palmer JR, Teras LR, Vachon CM, Yao S, Ong I, Nathanson KL, Weitzel JN, Boddicker N, Gnanaolivu R, Polley EC, Mer G, Cui G, Karam R, Richardson ME, Domchek SM, Yadav S, Hruska KS, Dolinsky J, Weroha SJ, Hart SN, Simard J, Masson JY, Pang YP, Couch FJ. Functional and Clinical Characterization of Variants of Uncertain Significance Identifies a Hotspot for Inactivating Missense Variants in RAD51C. Cancer Res 2023; 83:2557-2571. [PMID: 37253112 PMCID: PMC10390864 DOI: 10.1158/0008-5472.can-22-2319] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 10/07/2022] [Accepted: 05/25/2023] [Indexed: 06/01/2023]
Abstract
Pathogenic protein-truncating variants of RAD51C, which plays an integral role in promoting DNA damage repair, increase the risk of breast and ovarian cancer. A large number of RAD51C missense variants of uncertain significance (VUS) have been identified, but the effects of the majority of these variants on RAD51C function and cancer predisposition have not been established. Here, analysis of 173 missense variants by a homology-directed repair (HDR) assay in reconstituted RAD51C-/- cells identified 30 nonfunctional (deleterious) variants, including 18 in a hotspot within the ATP-binding region. The deleterious variants conferred sensitivity to cisplatin and olaparib and disrupted formation of RAD51C/XRCC3 and RAD51B/RAD51C/RAD51D/XRCC2 complexes. Computational analysis indicated the deleterious variant effects were consistent with structural effects on ATP-binding to RAD51C. A subset of the variants displayed similar effects on RAD51C activity in reconstituted human RAD51C-depleted cancer cells. Case-control association studies of deleterious variants in women with breast and ovarian cancer and noncancer controls showed associations with moderate breast cancer risk [OR, 3.92; 95% confidence interval (95% CI), 2.18-7.59] and high ovarian cancer risk (OR, 14.8; 95% CI, 7.71-30.36), similar to protein-truncating variants. This functional data supports the clinical classification of inactivating RAD51C missense variants as pathogenic or likely pathogenic, which may improve the clinical management of variant carriers. SIGNIFICANCE Functional analysis of the impact of a large number of missense variants on RAD51C function provides insight into RAD51C activity and information for classification of the cancer relevance of RAD51C variants.
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Affiliation(s)
| | | | | | - Gemma Montalban
- CHU de Quebec-Université Laval Research Center, Université Laval, Quebec City, Quebec, Canada
| | | | | | | | - Jie Na
- Mayo Clinic, Rochester, Minnesota
| | | | | | | | | | | | | | | | | | | | | | - Peter Kraft
- T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Sara Lindstrom
- Department of Epidemiology, University of Washington, Seattle, Washington
| | - Julie R. Palmer
- Slone Epidemiology Center at Boston University, Boston, Massachusetts
| | - Lauren R. Teras
- Behavioral and Epidemiology Research Group, American Cancer Society, Atlanta, Georgia
| | | | - Song Yao
- Roswell Park Comprehensive Cancer Center, Buffalo, New York
| | - Irene Ong
- University of Wisconsin-Madison, Madison, Wisconsin
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Jacques Simard
- CHU de Quebec-Université Laval Research Center, Université Laval, Quebec City, Quebec, Canada
| | - Jean Yves Masson
- CHU de Quebec-Université Laval Research Center, Université Laval, Quebec City, Quebec, Canada
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16
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Rawal Y, Jia L, Meir A, Zhou S, Kaur H, Ruben EA, Kwon Y, Bernstein KA, Jasin M, Taylor AB, Burma S, Hromas R, Mazin AV, Zhao W, Zhou D, Wasmuth EV, Greene EC, Sung P, Olsen SK. Structural insights into BCDX2 complex function in homologous recombination. Nature 2023; 619:640-649. [PMID: 37344589 PMCID: PMC10712684 DOI: 10.1038/s41586-023-06219-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Accepted: 05/15/2023] [Indexed: 06/23/2023]
Abstract
Homologous recombination (HR) fulfils a pivotal role in the repair of DNA double-strand breaks and collapsed replication forks1. HR depends on the products of several paralogues of RAD51, including the tetrameric complex of RAD51B, RAD51C, RAD51D and XRCC2 (BCDX2)2. BCDX2 functions as a mediator of nucleoprotein filament assembly by RAD51 and single-stranded DNA (ssDNA) during HR, but its mechanism remains undefined. Here we report cryogenic electron microscopy reconstructions of human BCDX2 in apo and ssDNA-bound states. The structures reveal how the amino-terminal domains of RAD51B, RAD51C and RAD51D participate in inter-subunit interactions that underpin complex formation and ssDNA-binding specificity. Single-molecule DNA curtain analysis yields insights into how BCDX2 enhances RAD51-ssDNA nucleoprotein filament assembly. Moreover, our cryogenic electron microscopy and functional analyses explain how RAD51C alterations found in patients with cancer3-6 inactivate DNA binding and the HR mediator activity of BCDX2. Our findings shed light on the role of BCDX2 in HR and provide a foundation for understanding how pathogenic alterations in BCDX2 impact genome repair.
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Affiliation(s)
- Yashpal Rawal
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Lijia Jia
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Aviv Meir
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, NY, USA
| | - Shuo Zhou
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Hardeep Kaur
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Eliza A Ruben
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Youngho Kwon
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Kara A Bernstein
- Department of Biochemistry & Biophysics, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Alexander B Taylor
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Sandeep Burma
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
- Department of Neurosurgery, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Robert Hromas
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Alexander V Mazin
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Weixing Zhao
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Daohong Zhou
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Elizabeth V Wasmuth
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - Eric C Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, NY, USA.
| | - Patrick Sung
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
| | - Shaun K Olsen
- Department of Biochemistry & Structural Biology and Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA.
- Glenn Biggs Institute for Alzheimer's and Neurodegenerative Diseases, San Antonio, TX, USA.
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17
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Greenhough LA, Liang CC, Belan O, Kunzelmann S, Maslen S, Rodrigo-Brenni MC, Anand R, Skehel M, Boulton SJ, West SC. Structure and function of the RAD51B-RAD51C-RAD51D-XRCC2 tumour suppressor. Nature 2023; 619:650-657. [PMID: 37344587 PMCID: PMC7614784 DOI: 10.1038/s41586-023-06179-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 05/08/2023] [Indexed: 06/23/2023]
Abstract
Homologous recombination is a fundamental process of life. It is required for the protection and restart of broken replication forks, the repair of chromosome breaks and the exchange of genetic material during meiosis. Individuals with mutations in key recombination genes, such as BRCA2 (also known as FANCD1), or the RAD51 paralogues RAD51B, RAD51C (also known as FANCO), RAD51D, XRCC2 (also known as FANCU) and XRCC3, are predisposed to breast, ovarian and prostate cancers1-10 and the cancer-prone syndrome Fanconi anaemia11-13. The BRCA2 tumour suppressor protein-the product of BRCA2-is well characterized, but the cellular functions of the RAD51 paralogues remain unclear. Genetic knockouts display growth defects, reduced RAD51 focus formation, spontaneous chromosome abnormalities, sensitivity to PARP inhibitors and replication fork defects14,15, but the precise molecular roles of RAD51 paralogues in fork stability, DNA repair and cancer avoidance remain unknown. Here we used cryo-electron microscopy, AlphaFold2 modelling and structural proteomics to determine the structure of the RAD51B-RAD51C-RAD51D-XRCC2 complex (BCDX2), revealing that RAD51C-RAD51D-XRCC2 mimics three RAD51 protomers aligned within a nucleoprotein filament, whereas RAD51B is highly dynamic. Biochemical and single-molecule analyses showed that BCDX2 stimulates the nucleation and extension of RAD51 filaments-which are essential for recombinational DNA repair-in reactions that depend on the coupled ATPase activities of RAD51B and RAD51C. Our studies demonstrate that BCDX2 orchestrates RAD51 assembly on single stranded DNA for replication fork protection and double strand break repair, in reactions that are critical for tumour avoidance.
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Affiliation(s)
| | | | - Ondrej Belan
- The Francis Crick Institute, London, UK
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Division of Genetics, Brigham and Women's Hospital, Boston, MA, USA
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18
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Anwaar A, Varma AK, Baruah R. In Silico-Based Structural Evaluation to Categorize the Pathogenicity of Mutations Identified in the RAD Class of Proteins. ACS OMEGA 2023; 8:10266-10277. [PMID: 36969410 PMCID: PMC10034773 DOI: 10.1021/acsomega.2c07802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 02/10/2023] [Indexed: 06/18/2023]
Abstract
RAD genes, known as double-strand break repair proteins, play a major role in maintaining the genomic integrity of a cell by carrying out essential DNA repair functions via double-strand break repair pathways. Mutations in the RAD class of proteins show high susceptibility to breast and ovarian cancers; however, adequate research on the mutations identified in these genes has not been extensively reported for their deleterious effects. Changes in the folding pattern of RAD proteins play an important role in protein-protein interactions and also functions. Missense mutations identified from four cancer databases, cBioPortal, COSMIC, ClinVar, and gnomAD, cause aberrant conformations, which may lead to faulty DNA repair mechanisms. It is therefore necessary to evaluate the effects of pathogenic mutations of RAD proteins and their subsequent role in breast and ovarian cancers. In this study, we have used eight computational prediction servers to analyze pathogenic mutations and understand their effects on the protein structure and function. A total of 5122 missense mutations were identified from four different cancer databases, of which 1165 were predicted to be pathogenic using at least five pathogenicity prediction servers. These mutations were characterized as high-risk mutations based on their location in the conserved domains and subsequently subjected to structural stability characterization. The mutations included in the present study were selected from clinically relevant mutants in breast cancer pedigrees. Comparative folding patterns and intra-atomic interaction results showed alterations in the structural behavior of RAD proteins, specifically RAD51C triggered by mutations G125V and L138F and RAD51D triggered by mutations S207L and E233G.
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Affiliation(s)
- Aaliya Anwaar
- Advanced
Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai 410210, Maharashtra, India
| | - Ashok K. Varma
- Advanced
Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai 410210, Maharashtra, India
- Homi
Bhabha National Institute, Training School Complex, Anushaktinagar, Mumbai 400094, Maharashtra, India
| | - Reshita Baruah
- Advanced
Centre for Treatment, Research and Education in Cancer, Kharghar, Navi Mumbai 410210, Maharashtra, India
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19
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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: 8] [Impact Index Per Article: 8.0] [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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20
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Serous Tubal Intraepithelial Carcinoma in a Risk-reducing Salpingo-oophorectomy Specimen From a RAD51D Mutation Carrier: A Case Report. Int J Gynecol Pathol 2023; 42:89-92. [PMID: 35149617 DOI: 10.1097/pgp.0000000000000857] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The RAD51D gene codes a protein-paralog of the RAD51 DNA recombinase, which catalyzes DNA strand exchange during homologous recombination. Similar to BRCA1 / BRCA2 , mutations in RAD51D both predispose to ovarian carcinoma and impart sensitivity to poly (ADP-ribose) polymerase inhibitors in preclinical studies. Based on cancer risk prediction models, RAD51D mutations pose a moderate-to-high risk for ovarian cancer warranting consideration for risk-reducing surgery. We report a case of serous tubal intraepithelial carcinoma in a patient undergoing risk-reducing total hysterectomy with bilateral salpingo-oophorectomy for a RAD51D pathogenic variant. The histopathologic and p53-immunophenotypic features of this lesion are similar to those reported previously in BRCA1 / BRCA2 mutation carriers and those of serous tubal intraepithelial carcinoma associated with sporadic high-grade serous carcinomas. These features include marked increase in nuclear-to-cytoplasmic ratio, loss of cell polarity, absence of ciliation, prominent nucleoli, mitotic activity, epithelial stratification, surface exfoliative changes, and complete loss of p53 staining. Although familial ovarian cancers with mutations in RAD51D -or other genes in the Fanconi anemia pathway-are much less common those with BRCA1 / BRCA2 mutations, our findings support a common phenotype for early serous cancers in this pathway.
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21
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Systematic proximal mapping of the classical RAD51 paralogs unravel functionally and clinically relevant interactors for genome stability. PLoS Genet 2022; 18:e1010495. [DOI: 10.1371/journal.pgen.1010495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/02/2022] [Accepted: 10/24/2022] [Indexed: 11/15/2022] Open
Abstract
Homologous recombination (HR) plays an essential role in the maintenance of genome stability by promoting the repair of cytotoxic DNA double strand breaks (DSBs). More recently, the HR pathway has emerged as a core component of the response to replication stress, in part by protecting stalled replication forks from nucleolytic degradation. In that regard, the mammalian RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, and XRCC3) have been involved in both HR-mediated DNA repair and collapsed replication fork resolution. Still, it remains largely obscure how they participate in both processes, thereby maintaining genome stability and preventing cancer development. To gain better insight into their contribution in cellulo, we mapped the proximal interactome of the classical RAD51 paralogs using the BioID approach. Aside from identifying the well-established BCDX2 and CX3 sub-complexes, the spliceosome machinery emerged as an integral component of our proximal mapping, suggesting a crosstalk between this pathway and the RAD51 paralogs. Furthermore, we noticed that factors involved RNA metabolic pathways are significantly modulated within the BioID of the classical RAD51 paralogs upon exposure to hydroxyurea (HU), pointing towards a direct contribution of RNA processing during replication stress. Importantly, several members of these pathways have prognostic potential in breast cancer (BC), where their RNA expression correlates with poorer patient outcome. Collectively, this study uncovers novel functionally relevant partners of the different RAD51 paralogs in the maintenance of genome stability that could be used as biomarkers for the prognosis of BC.
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22
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Association between XRCC3 p.Thr241Met polymorphism and risk of glioma: A systematic review and meta-analysis. PLoS One 2022; 17:e0276313. [PMID: 36264998 PMCID: PMC9584405 DOI: 10.1371/journal.pone.0276313] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 10/04/2022] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The XRCC3 p.Thr241Met (rs861539) polymorphism has been extensively studied for its association with glioma risk, but results remain conflicting. Therefore, we performed a systematic review and meta-analysis to resolve this inconsistency. METHODS Studies published up to June 10, 2022, were searched in PubMed, Web of Science, Scopus, VIP, Wanfang, and China National Knowledge Infrastructure databases and screened for eligibility. Then, the combined odds ratio (OR) of the included studies was estimated based on five genetic models, i.e., homozygous (Met/Met vs. Thr/Thr), heterozygous (Thr/Met vs. Thr/Thr), dominant (Thr/Met + Met/Met vs. Thr/Thr), recessive (Met/Met vs. Thr/Thr + Thr/Met) and allele (Met vs. Thr). The study protocol was preregistered at PROSPERO (registration number: CRD42021235704). RESULTS Overall, our meta-analysis of 14 eligible studies involving 12,905 subjects showed that the p.Thr241Met polymorphism was significantly associated with increased glioma risk in both homozygous and recessive models (homozygous, OR = 1.381, 95% CI = 1.081-1.764, P = 0.010; recessive, OR = 1.305, 95% CI = 1.140-1.493, P<0.001). Subgroup analyses by ethnicity also revealed a statistically significant association under the two aforementioned genetic models, but only in the Asian population and not in Caucasians (P>0.05). CONCLUSION We demonstrated that the XRCC3 p.Thr241Met polymorphism is associated with an increased risk of glioma only in the homozygous and recessive models.
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23
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Prakash R, Rawal Y, Sullivan MR, Grundy MK, Bret H, Mihalevic MJ, Rein HL, Baird JM, Darrah K, Zhang F, Wang R, Traina TA, Radke MR, Kaufmann SH, Swisher EM, Guérois R, Modesti M, Sung P, Jasin M, Bernstein KA. Homologous recombination-deficient mutation cluster in tumor suppressor RAD51C identified by comprehensive analysis of cancer variants. Proc Natl Acad Sci U S A 2022; 119:e2202727119. [PMID: 36099300 PMCID: PMC9499524 DOI: 10.1073/pnas.2202727119] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 08/09/2022] [Indexed: 01/05/2023] Open
Abstract
Mutations in homologous recombination (HR) genes, including BRCA1, BRCA2, and the RAD51 paralog RAD51C, predispose to tumorigenesis and sensitize cancers to DNA-damaging agents and poly(ADP ribose) polymerase inhibitors. However, ∼800 missense variants of unknown significance have been identified for RAD51C alone, impairing cancer risk assessment and therapeutic strategies. Here, we interrogated >50 RAD51C missense variants, finding that mutations in residues conserved with RAD51 strongly predicted HR deficiency and disrupted interactions with other RAD51 paralogs. A cluster of mutations was identified in and around the Walker A box that led to impairments in HR, interactions with three other RAD51 paralogs, binding to single-stranded DNA, and ATP hydrolysis. We generated structural models of the two RAD51 paralog complexes containing RAD51C, RAD51B-RAD51C-RAD51D-XRCC2 and RAD51C-XRCC3. Together with our functional and biochemical analyses, the structural models predict ATP binding at the interface of RAD51C interactions with other RAD51 paralogs, similar to interactions between monomers in RAD51 filaments, and explain the failure of RAD51C variants in binding multiple paralogs. Ovarian cancer patients with variants in this cluster showed exceptionally long survival, which may be relevant to the reversion potential of the variants. This comprehensive analysis provides a framework for RAD51C variant classification. Importantly, it also provides insight into the functioning of the RAD51 paralog complexes.
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Affiliation(s)
- Rohit Prakash
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Yashpal Rawal
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Meghan R. Sullivan
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - McKenzie K. Grundy
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Hélène Bret
- Institute for Integrative Biology of the Cell, Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, 91198 France
| | - Michael J. Mihalevic
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Hayley L. Rein
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Jared M. Baird
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Kristie Darrah
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Fang Zhang
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853
| | - Raymond Wang
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Tiffany A. Traina
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Marc R. Radke
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Washington School of Medicine, Seattle, WA 98195
| | - Scott H. Kaufmann
- Departments of Oncology and Molecular Pharmacology & Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905
| | - Elizabeth M. Swisher
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, University of Washington School of Medicine, Seattle, WA 98195
| | - Raphaël Guérois
- Institute for Integrative Biology of the Cell, Université Paris-Saclay, CEA, CNRS, Gif-sur-Yvette, 91198 France
| | - Mauro Modesti
- Cancer Research Center of Marseille, CNRS, INSERM, Institut Paoli-Calmettes, Aix-Marseille Université, Marseille, 13273 France
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Kara A. Bernstein
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
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24
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Halder S, Ranjha L, Taglialatela A, Ciccia A, Cejka P. Strand annealing and motor driven activities of SMARCAL1 and ZRANB3 are stimulated by RAD51 and the paralog complex. Nucleic Acids Res 2022; 50:8008-8022. [PMID: 35801922 PMCID: PMC9371921 DOI: 10.1093/nar/gkac583] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 06/13/2022] [Accepted: 06/23/2022] [Indexed: 12/17/2022] Open
Abstract
SMARCAL1, ZRANB3 and HLTF are required for the remodeling of replication forks upon stress to promote genome stability. RAD51, along with the RAD51 paralog complex, were also found to have recombination-independent functions in fork reversal, yet the underlying mechanisms remained unclear. Using reconstituted reactions, we build upon previous data to show that SMARCAL1, ZRANB3 and HLTF have unequal biochemical capacities, explaining why they have non-redundant functions. SMARCAL1 uniquely anneals RPA-coated ssDNA, which depends on its direct interaction with RPA, but not on ATP. SMARCAL1, along with ZRANB3, but not HLTF efficiently employ ATPase driven translocase activity to rezip RPA-covered bubbled DNA, which was proposed to mimic elements of fork reversal. In contrast, ZRANB3 and HLTF but not SMARCAL1 are efficient in branch migration that occurs downstream in fork remodeling. We also show that low concentrations of RAD51 and the RAD51 paralog complex, RAD51B–RAD51C–RAD51D–XRCC2 (BCDX2), directly stimulate the motor-driven activities of SMARCAL1 and ZRANB3 but not HLTF, and the interplay is underpinned by physical interactions. Our data provide a possible mechanism explaining previous cellular experiments implicating RAD51 and BCDX2 in fork reversal.
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Affiliation(s)
- Swagata Halder
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland
| | - Lepakshi Ranjha
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland
| | - Angelo Taglialatela
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, NY, USA
| | - Alberto Ciccia
- Department of Genetics and Development, Herbert Irving Comprehensive Cancer Center, Columbia University Irving Medical Center, NY, USA
| | - Petr Cejka
- Institute for Research in Biomedicine, Università della Svizzera italiana (USI), Faculty of Biomedical Sciences, Bellinzona, Switzerland.,Department of Biology, Institute of Biochemistry, Eidgenössische Technische Hochschule (ETH), Zürich, Switzerland
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25
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The Genetic and Molecular Analyses of RAD51C and RAD51D Identifies Rare Variants Implicated in Hereditary Ovarian Cancer from a Genetically Unique Population. Cancers (Basel) 2022; 14:cancers14092251. [PMID: 35565380 PMCID: PMC9104874 DOI: 10.3390/cancers14092251] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/13/2022] [Accepted: 04/20/2022] [Indexed: 12/03/2022] Open
Abstract
To identify candidate variants in RAD51C and RAD51D ovarian cancer (OC) predisposing genes by investigating French Canadians (FC) exhibiting unique genetic architecture. Candidates were identified by whole exome sequencing analysis of 17 OC families and 53 early-onset OC cases. Carrier frequencies were determined by the genetic analysis of 100 OC or HBOC families, 438 sporadic OC cases and 1025 controls. Variants of unknown function were assayed for their biological impact and/or cellular sensitivity to olaparib. RAD51C c.414G>C;p.Leu138Phe and c.705G>T;p.Lys235Asn and RAD51D c.137C>G;p.Ser46Cys, c.620C>T;p.Ser207Leu and c.694C>T;p.Arg232Ter were identified in 17.6% of families and 11.3% of early-onset cases. The highest carrier frequency was observed in OC families (1/44, 2.3%) and sporadic cases (15/438, 3.4%) harbouring RAD51D c.620C>T versus controls (1/1025, 0.1%). Carriers of c.620C>T (n = 7), c.705G>T (n = 2) and c.137C>G (n = 1) were identified in another 538 FC OC cases. RAD51C c.705G>T affected splicing by skipping exon four, while RAD51D p.Ser46Cys affected protein stability and conferred olaparib sensitivity. Genetic and functional assays implicate RAD51C c.705G>T and RAD51D c.137C>G as likely pathogenic variants in OC. The high carrier frequency of RAD51D c.620C>T in FC OC cases validates previous findings. Our findings further support the role of RAD51C and RAD51D in hereditary OC.
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26
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DNA Damage Clustering after Ionizing Radiation and Consequences in the Processing of Chromatin Breaks. Molecules 2022; 27:molecules27051540. [PMID: 35268641 PMCID: PMC8911773 DOI: 10.3390/molecules27051540] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 11/26/2022] Open
Abstract
Charged-particle radiotherapy (CPRT) utilizing low and high linear energy transfer (low-/high-LET) ionizing radiation (IR) is a promising cancer treatment modality having unique physical energy deposition properties. CPRT enables focused delivery of a desired dose to the tumor, thus achieving a better tumor control and reduced normal tissue toxicity. It increases the overall radiation tolerance and the chances of survival for the patient. Further improvements in CPRT are expected from a better understanding of the mechanisms governing the biological effects of IR and their dependence on LET. There is increasing evidence that high-LET IR induces more complex and even clustered DNA double-strand breaks (DSBs) that are extremely consequential to cellular homeostasis, and which represent a considerable threat to genomic integrity. However, from the perspective of cancer management, the same DSB characteristics underpin the expected therapeutic benefit and are central to the rationale guiding current efforts for increased implementation of heavy ions (HI) in radiotherapy. Here, we review the specific cellular DNA damage responses (DDR) elicited by high-LET IR and compare them to those of low-LET IR. We emphasize differences in the forms of DSBs induced and their impact on DDR. Moreover, we analyze how the distinct initial forms of DSBs modulate the interplay between DSB repair pathways through the activation of DNA end resection. We postulate that at complex DSBs and DSB clusters, increased DNA end resection orchestrates an increased engagement of resection-dependent repair pathways. Furthermore, we summarize evidence that after exposure to high-LET IR, error-prone processes outcompete high fidelity homologous recombination (HR) through mechanisms that remain to be elucidated. Finally, we review the high-LET dependence of specific DDR-related post-translational modifications and the induction of apoptosis in cancer cells. We believe that in-depth characterization of the biological effects that are specific to high-LET IR will help to establish predictive and prognostic signatures for use in future individualized therapeutic strategies, and will enhance the prospects for the development of effective countermeasures for improved radiation protection during space travel.
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27
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Bijlani S, Pang KM, Sivanandam V, Singh A, Chatterjee S. The Role of Recombinant AAV in Precise Genome Editing. Front Genome Ed 2022; 3:799722. [PMID: 35098210 PMCID: PMC8793687 DOI: 10.3389/fgeed.2021.799722] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 12/14/2021] [Indexed: 12/14/2022] Open
Abstract
The replication-defective, non-pathogenic, nearly ubiquitous single-stranded adeno-associated viruses (AAVs) have gained importance since their discovery about 50 years ago. Their unique life cycle and virus-cell interactions have led to the development of recombinant AAVs as ideal genetic medicine tools that have evolved into effective commercialized gene therapies. A distinctive property of AAVs is their ability to edit the genome precisely. In contrast to all current genome editing platforms, AAV exclusively utilizes the high-fidelity homologous recombination (HR) pathway and does not require exogenous nucleases for prior cleavage of genomic DNA. Together, this leads to a highly precise editing outcome that preserves genomic integrity without incorporation of indel mutations or viral sequences at the target site while also obviating the possibility of off-target genotoxicity. The stem cell-derived AAV (AAVHSCs) were found to mediate precise and efficient HR with high on-target accuracy and at high efficiencies. AAVHSC editing occurs efficiently in post-mitotic cells and tissues in vivo. Additionally, AAV also has the advantage of an intrinsic delivery mechanism. Thus, this distinctive genome editing platform holds tremendous promise for the correction of disease-associated mutations without adding to the mutational burden. This review will focus on the unique properties of direct AAV-mediated genome editing and their potential mechanisms of action.
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28
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Homologous Recombination as a Fundamental Genome Surveillance Mechanism during DNA Replication. Genes (Basel) 2021; 12:genes12121960. [PMID: 34946909 PMCID: PMC8701046 DOI: 10.3390/genes12121960] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 12/06/2021] [Accepted: 12/07/2021] [Indexed: 12/28/2022] Open
Abstract
Accurate and complete genome replication is a fundamental cellular process for the proper transfer of genetic material to cell progenies, normal cell growth, and genome stability. However, a plethora of extrinsic and intrinsic factors challenge individual DNA replication forks and cause replication stress (RS), a hallmark of cancer. When challenged by RS, cells deploy an extensive range of mechanisms to safeguard replicating genomes and limit the burden of DNA damage. Prominent among those is homologous recombination (HR). Although fundamental to cell division, evidence suggests that cancer cells exploit and manipulate these RS responses to fuel their evolution and gain resistance to therapeutic interventions. In this review, we focused on recent insights into HR-mediated protection of stress-induced DNA replication intermediates, particularly the repair and protection of daughter strand gaps (DSGs) that arise from discontinuous replication across a damaged DNA template. Besides mechanistic underpinnings of this process, which markedly differ depending on the extent and duration of RS, we highlight the pathophysiological scenarios where DSG repair is naturally silenced. Finally, we discuss how such pathophysiological events fuel rampant mutagenesis, promoting cancer evolution, but also manifest in adaptative responses that can be targeted for cancer therapy.
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29
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Kong M, Greene EC. Mechanistic Insights From Single-Molecule Studies of Repair of Double Strand Breaks. Front Cell Dev Biol 2021; 9:745311. [PMID: 34869333 PMCID: PMC8636147 DOI: 10.3389/fcell.2021.745311] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 10/28/2021] [Indexed: 01/01/2023] Open
Abstract
DNA double strand breaks (DSBs) are among some of the most deleterious forms of DNA damage. Left unrepaired, they are detrimental to genome stability, leading to high risk of cancer. Two major mechanisms are responsible for the repair of DSBs, homologous recombination (HR) and nonhomologous end joining (NHEJ). The complex nature of both pathways, involving a myriad of protein factors functioning in a highly coordinated manner at distinct stages of repair, lend themselves to detailed mechanistic studies using the latest single-molecule techniques. In avoiding ensemble averaging effects inherent to traditional biochemical or genetic methods, single-molecule studies have painted an increasingly detailed picture for every step of the DSB repair processes.
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Affiliation(s)
| | - Eric C. Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University Irving Medical Center, New York, NY, United States
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30
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Allkanjari K, Baldock RA. Beyond base excision repair: an evolving picture of mitochondrial DNA repair. Biosci Rep 2021; 41:BSR20211320. [PMID: 34608928 PMCID: PMC8527207 DOI: 10.1042/bsr20211320] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/29/2021] [Accepted: 10/04/2021] [Indexed: 12/11/2022] Open
Abstract
Mitochondria are highly specialised organelles required for key cellular processes including ATP production through cellular respiration and controlling cell death via apoptosis. Unlike other organelles, mitochondria contain their own DNA genome which encodes both protein and RNA required for cellular respiration. Each cell may contain hundreds to thousands of copies of the mitochondrial genome, which is essential for normal cellular function - deviation of mitochondrial DNA (mtDNA) copy number is associated with cellular ageing and disease. Furthermore, mtDNA lesions can arise from both endogenous or exogenous sources and must either be tolerated or corrected to preserve mitochondrial function. Importantly, replication of damaged mtDNA can lead to stalling and introduction of mutations or genetic loss, mitochondria have adapted mechanisms to repair damaged DNA. These mechanisms rely on nuclear-encoded DNA repair proteins that are translocated into the mitochondria. Despite the presence of many known nuclear DNA repair proteins being found in the mitochondrial proteome, it remains to be established which DNA repair mechanisms are functional in mammalian mitochondria. Here, we summarise the existing and emerging research, alongside examining proteomic evidence, demonstrating that mtDNA damage can be repaired using Base Excision Repair (BER), Homologous Recombination (HR) and Microhomology-mediated End Joining (MMEJ). Critically, these repair mechanisms do not operate in isolation and evidence for interplay between pathways and repair associated with replication is discussed. Importantly, characterising non-canonical functions of key proteins and understanding the bespoke pathways used to tolerate, repair or bypass DNA damage will be fundamental in fully understanding the causes of mitochondrial genome mutations and mitochondrial dysfunction.
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Affiliation(s)
- Kathrin Allkanjari
- Formerly: Solent University Southampton, East Park Terrace, Southampton, SO14 0YN, UK
| | - Robert A. Baldock
- School of Natural and Social Sciences, University of Gloucestershire, Francis Close Hall, Swindon Road, Cheltenham GL50 4AZ, UK
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31
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Setton J, Selenica P, Mukherjee S, Shah R, Pecorari I, McMillan B, Pei IX, Kemel Y, Ceyhan-Birsoy O, Sheehan M, Tkachuk K, Brown DN, Zhang L, Cadoo K, Powell S, Weigelt B, Robson M, Riaz N, Offit K, Reis-Filho JS, Mandelker D. Germline RAD51B variants confer susceptibility to breast and ovarian cancers deficient in homologous recombination. NPJ Breast Cancer 2021; 7:135. [PMID: 34635660 PMCID: PMC8505423 DOI: 10.1038/s41523-021-00339-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 08/24/2021] [Indexed: 12/13/2022] Open
Abstract
Pathogenic germline mutations in the RAD51 paralog genes RAD51C and RAD51D, are known to confer susceptibility to ovarian and triple-negative breast cancer. Here, we investigated whether germline loss-of-function variants affecting another RAD51 paralog gene, RAD51B, are also associated with breast and ovarian cancer. Among 3422 consecutively accrued breast and ovarian cancer patients consented to tumor/germline sequencing, the observed carrier frequency of loss-of-function germline RAD51B variants was significantly higher than control cases from the gnomAD population database (0.26% vs 0.09%), with an odds ratio of 2.69 (95% CI: 1.4-5.3). Furthermore, we demonstrate that tumors harboring biallelic RAD51B alteration are deficient in homologous recombination DNA repair deficiency (HRD), as evidenced by analysis of sequencing data and in vitro functional assays. Our findings suggest that RAD51B should be considered as an addition to clinical germline testing panels for breast and ovarian cancer susceptibility.
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Affiliation(s)
- Jeremy Setton
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Pier Selenica
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- GROW School for Ontology and Developmental Biology, University of Maastricht, Maastricht, The Netherlands
| | - Semanti Mukherjee
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Rachna Shah
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Isabella Pecorari
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Biko McMillan
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Isaac X Pei
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Yelena Kemel
- Niehaus Center of Inherited Cancer Genomics, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Ozge Ceyhan-Birsoy
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Margaret Sheehan
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Kaitlyn Tkachuk
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - David N Brown
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Liying Zhang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Karen Cadoo
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Simon Powell
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
- Molecular Biology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Britta Weigelt
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Mark Robson
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Nadeem Riaz
- Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Kenneth Offit
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Jorge S Reis-Filho
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
| | - Diana Mandelker
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA.
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32
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Amirifar P, Mehrmohamadi M, Ranjouri MR, Akrami SM, Rezaei N, Saberi A, Yazdani R, Abolhassani H, Aghamohammadi A. Genetic Risk Variants for Class Switching Recombination Defects in Ataxia-Telangiectasia Patients. J Clin Immunol 2021; 42:72-84. [PMID: 34628594 PMCID: PMC8821084 DOI: 10.1007/s10875-021-01147-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Accepted: 09/27/2021] [Indexed: 11/04/2022]
Abstract
Background Ataxia-telangiectasia (A-T) is a rare autosomal recessive disorder caused by mutations in the ataxia telangiectasia mutated (ATM) gene. A-T patients manifest considerable variability in clinical and immunological features, suggesting the presence of genetic modifying factors. A striking heterogeneity has been observed in class switching recombination (CSR) in A-T patients which cannot be explained by the severity of ATM mutations. Methods To investigate the cause of variable CSR in A-T patients, we applied whole-exome sequencing (WES) in 20 A-T patients consisting of 10 cases with CSR defect (CSR-D) and 10 controls with normal CSR (CSR-N). Comparative analyses on modifier variants found in the exomes of these two groups of patients were performed. Results For the first time, we identified some variants in the exomes of the CSR-D group that were significantly associated with antigen processing and presentation pathway. Moreover, in this group of patients, the variants in four genes involved in DNA double-strand breaks (DSB) repair signaling, in particular, XRCC3 were observed, suggesting an association with CSR defect. Conclusion Additional impact of certain variants, along with ATM mutations, may explain the heterogeneity in CSR defect phenotype among A-T patients. It can be concluded that genetic modulators play an important role in the course of A-T disease and its clinical severity. Supplementary Information The online version contains supplementary material available at 10.1007/s10875-021-01147-8.
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Affiliation(s)
- Parisa Amirifar
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.,Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran
| | - Mahya Mehrmohamadi
- Department of Biotechnology, College of Science, University of Tehran, Tehran, Iran
| | - Mohammad Reza Ranjouri
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran
| | - Seyed Mohammad Akrami
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Nima Rezaei
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.,Primary Immunodeficiency Diseases Network (PIDNet), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Ali Saberi
- Department of Computer Engineering, Sharif University of Technology, Tehran, Iran
| | - Reza Yazdani
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran.,Primary Immunodeficiency Diseases Network (PIDNet), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Hassan Abolhassani
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran. .,Division of Clinical Immunology, Department of Biosciences and Nutrition, NEO, Karolinska Institute, Blickagangen 16, 14157, Stockholm, Sweden. .,Division of Clinical Immunology, Department of Laboratory Medicine, Karolinska Institute at Karolinska University Hospital Huddinge, Stockholm, Sweden.
| | - Asghar Aghamohammadi
- Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Science, Tehran, Iran. .,Children's Medical Center Hospital, 62 Qarib St., Keshavarz Blvd, 14194, Tehran, Iran.
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33
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Prakash R, Freyer L, Saiz N, Gavrilov S, Wang RQ, Romanienko PJ, Lacy E, Hadjantonakis AK, Jasin M. XRCC3 loss leads to midgestational embryonic lethality in mice. DNA Repair (Amst) 2021; 108:103227. [PMID: 34601382 DOI: 10.1016/j.dnarep.2021.103227] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/09/2021] [Accepted: 09/11/2021] [Indexed: 10/20/2022]
Abstract
RAD51 paralogs are key components of the homologous recombination (HR) machinery. Mouse mutants have been reported for four of the canonical RAD51 paralogs, and each of these mutants exhibits embryonic lethality, although at different gestational stages. However, the phenotype of mice deficient in the fifth RAD51 paralog, XRCC3, has not been reported. Here we report that Xrcc3 knockout mice exhibit midgestational lethality, with mild phenotypes beginning at about E8.25 but severe developmental abnormalities evident by E9.0-9.5. The most obvious phenotypes are small size and a failure of the embryo to turn to a fetal position. A knockin mutation at a key ATPase residue in the Walker A box results in embryonic lethality at a similar stage. Death of knockout mice can be delayed a few days for some embryos by homozygous or heterozygous Trp53 mutation, in keeping with an important role for XRCC3 in promoting genome integrity. Given that XRCC3 is a unique member of one of two RAD51 paralog complexes with RAD51C, these results demonstrate that both RAD51 paralog complexes are required for mouse development.
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Affiliation(s)
- Rohit Prakash
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States; Regeneron Pharmaceuticals, Tarrytown, New York, NY, United States
| | - Laina Freyer
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States; Institut Pasteur, Paris, France
| | - Néstor Saiz
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States; Rockefeller University Press, New York, NY, United States
| | - Svetlana Gavrilov
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States; Bristol-Myers Squibb, New York, NY, United States
| | - Raymond Q Wang
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States
| | - Peter J Romanienko
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States; Rutgers-Cancer Institute of New Jersey, New Brunswick, NJ, United States
| | - Elizabeth Lacy
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States
| | - Anna-Katerina Hadjantonakis
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, 430 East 67 Street, New York, NY 10065, United States.
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34
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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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35
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Inhibiting homologous recombination by targeting RAD51 protein. Biochim Biophys Acta Rev Cancer 2021; 1876:188597. [PMID: 34332021 DOI: 10.1016/j.bbcan.2021.188597] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 07/09/2021] [Accepted: 07/24/2021] [Indexed: 02/06/2023]
Abstract
Homologous recombination (HR) is involved in repairing DNA double-strand breaks (DSB), the most harmful for the cell. Regulating HR is essential for maintaining genomic stability. In many forms of cancer, overactivation of HR increases tumor resistance to DNA-damaging treatments. RAD51, HR's core protein, is very often over-expressed in these cancers and plays a critical role in cancer cell development and survival. Targeting RAD51 directly to reduce its activity and its expression is therefore one strategy to sensitize and overcome resistance cancer cells to existing DNA-damaging therapies which remains the limiting factor for the success of targeted therapy. This review describes the structure and biological roles of RAD51, summarizes the different targeted sites of RAD51 and its inhibitory compounds discovered and described in the last decade.
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Rein HL, Bernstein KA, Baldock RA. RAD51 paralog function in replicative DNA damage and tolerance. Curr Opin Genet Dev 2021; 71:86-91. [PMID: 34311385 DOI: 10.1016/j.gde.2021.06.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 06/22/2021] [Accepted: 06/23/2021] [Indexed: 12/14/2022]
Abstract
RAD51 paralog gene mutations are observed in both hereditary breast and ovarian cancers. Classically, defects in RAD51 paralog function are associated with homologous recombination (HR) deficiency and increased genomic instability. Several recent investigative advances have enabled characterization of non-canonical RAD51 paralog function during DNA replication. Here we discuss the role of the RAD51 paralogs and their associated complexes in integrating a robust response to DNA replication stress. We highlight recent discoveries suggesting that the RAD51 paralogs complexes mediate lesion-specific tolerance of replicative stress following exposure to alkylating agents and the requirement for the Shu complex in fork restart upon fork stalling by dNTP depletion. In addition, we describe the role of the BCDX2 complex in restraining and promoting fork remodeling in response to fluctuating dNTP pools. Finally, we highlight recent work demonstrating a requirement for RAD51C in recognizing and tolerating methyl-adducts. In each scenario, RAD51 paralog complexes play a central role in lesion recognition and bypass in a replicative context. Future studies will determine how these critical functions for RAD51 paralog complexes contribute to tumorigenesis.
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Affiliation(s)
- Hayley L Rein
- University of Pittsburgh School of Medicine, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, USA
| | - Kara A Bernstein
- University of Pittsburgh School of Medicine, Department of Pharmacology and Chemical Biology, Pittsburgh, PA, USA
| | - Robert A Baldock
- School of Natural and Social Sciences, University of Gloucestershire, Cheltenham, UK.
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Alvarez-Palomo AB, Requena-Osete J, Delgado-Morales R, Moreno-Manzano V, Grau-Bove C, Tejera AM, Otero MJ, Barrot C, Santos-Barriopedro I, Vaquero A, Mezquita-Pla J, Moran S, Naya CH, Garcia-Martínez I, Pérez FV, Blasco MA, Esteller M, Edel MJ. A synthetic mRNA cell reprogramming method using CYCLIN D1 promotes DNA repair, generating improved genetically stable human induced pluripotent stem cells. Stem Cells 2021; 39:866-881. [PMID: 33621399 DOI: 10.1002/stem.3358] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
A key challenge for clinical application of induced pluripotent stem cells (iPSC) to accurately model and treat human pathologies depends on developing a method to generate genetically stable cells to reduce long-term risks of cell transplant therapy. Here, we hypothesized that CYCLIN D1 repairs DNA by highly efficient homologous recombination (HR) during reprogramming to iPSC that reduces genetic instability and threat of neoplastic growth. We adopted a synthetic mRNA transfection method using clinically compatible conditions with CYCLIN D1 plus base factors (OCT3/4, SOX2, KLF4, LIN28) and compared with methods that use C-MYC. We demonstrate that CYCLIN D1 made iPSC have (a) lower multitelomeric signal, (b) reduced double-strand DNA breaks, (c) correct nuclear localization of RAD51 protein expression, and (d) reduced single-nucleotide polymorphism (SNP) changes per chromosome, compared with the classical reprogramming method using C-MYC. CYCLIN D1 iPSC have reduced teratoma Ki67 cell growth kinetics and derived neural stem cells successfully engraft in a hostile spinal cord injury (SCI) microenvironment with efficient survival, differentiation. We demonstrate that CYCLIN D1 promotes double-stranded DNA damage repair predominantly through HR during cell reprogramming to efficiently produce iPSC. CYCLIN D1 reduces general cell stress associated with significantly lower SIRT1 gene expression and can rescue Sirt1 null mouse cell reprogramming. In conclusion, we show synthetic mRNA transfection of CYCLIN D1 repairs DNA during reprogramming resulting in significantly improved genetically stable footprint in human iPSC, enabling a new cell reprogramming method for more accurate and reliable generation of human iPSC for disease modeling and future clinical applications.
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Affiliation(s)
- Ana Belén Alvarez-Palomo
- Molecular Genetics and Control of Pluripotency Laboratory, Department of Biomedicine, Institute of Neuroscience, Faculty of Medicine, University of Barcelona, Hospital Clinic, Barcelona, Catalonia, Spain
- Cell Therapy Service, Banc de Sang i Teixits (BST), Barcelona, Spain
| | - Jordi Requena-Osete
- Molecular Genetics and Control of Pluripotency Laboratory, Department of Biomedicine, Institute of Neuroscience, Faculty of Medicine, University of Barcelona, Hospital Clinic, Barcelona, Catalonia, Spain
- Institute of Clinical Medicine, University of Oslo, Oslo, Norway
- Division of Mental Health and Addiction, NORMENT, Centre for Mental Disorders Research, Oslo, Norway
| | - Raul Delgado-Morales
- Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience (MHeNs), Maastricht University, Maastricht, The Netherlands
| | - Victoria Moreno-Manzano
- Neuronal and Tissue Regeneration Laboratory, Príncipe Felipe Research Center, Valencia, Spain
| | - Carme Grau-Bove
- Molecular Genetics and Control of Pluripotency Laboratory, Department of Biomedicine, Institute of Neuroscience, Faculty of Medicine, University of Barcelona, Hospital Clinic, Barcelona, Catalonia, Spain
| | - Agueda M Tejera
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Manel Juan Otero
- Hospital Clinic, Department of Clinical Immunology, Biomedical Diagnostic Center (CDB), Villarroel, Catalonia, Spain
| | - Carme Barrot
- Forensic Genetics Laboratory, Legal Medicine Department, Faculty of Medicine, University of Barcelona, Barcelona, Spain
| | - Irene Santos-Barriopedro
- Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
| | - Alejandro Vaquero
- Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
| | - Jovita Mezquita-Pla
- Molecular Genetics and Control of Pluripotency Laboratory, Department of Biomedicine, Institute of Neuroscience, Faculty of Medicine, University of Barcelona, Hospital Clinic, Barcelona, Catalonia, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Sebastian Moran
- Chromatin Biology Laboratory, Cancer Epigenetics and Biology Program (PEBC), Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Catalonia, Spain
| | - Carlos Hobeich Naya
- Congenital Coagulopathies Department, Banc de Sang i Teixits (BST), Barcelona, Spain
- Transfusional Medicine, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona (VHIR-UAB), Barcelona, Spain
| | - Iris Garcia-Martínez
- Congenital Coagulopathies Department, Banc de Sang i Teixits (BST), Barcelona, Spain
- Transfusional Medicine, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona (VHIR-UAB), Barcelona, Spain
| | - Francisco Vidal Pérez
- Congenital Coagulopathies Department, Banc de Sang i Teixits (BST), Barcelona, Spain
- Transfusional Medicine, Vall d'Hebron Research Institute, Universitat Autònoma de Barcelona (VHIR-UAB), Barcelona, Spain
- CIBER de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - María A Blasco
- Telomeres and Telomerase Group, Molecular Oncology Program, Spanish National Cancer Centre (CNIO), Madrid, Spain
| | - Manel Esteller
- Josep Carreras Leukemia Research Institute (IJC), Badalona, Barcelona, Catalonia, Spain
- Centro de Investigacion Biomedica en Red Cancer (CIBERONC), Madrid, Spain
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Catalonia, Spain
- Physiological Sciences Department, School of Medicine and Health Sciences, University of Barcelona (UB), Barcelona, Catalonia, Spain
| | - Michael J Edel
- Molecular Genetics and Control of Pluripotency Laboratory, Department of Biomedicine, Institute of Neuroscience, Faculty of Medicine, University of Barcelona, Hospital Clinic, Barcelona, Catalonia, Spain
- Victor Chang Cardiac Research Institute, Sydney, New South Wales, Australia
- University of Western Australia, School of Medicine and Pharmacology, Harry Perkins Research Institute, Centre for Cell Therapy and Regenerative Medicine (CCTRM), Perth, Western Australia, Australia
- Centro de Oftalmología Barraquer, Institut Universitari Barraquer, Universitat Autònoma de Barcelona, Bellaterra, Spain
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Orhan E, Velazquez C, Tabet I, Sardet C, Theillet C. Regulation of RAD51 at the Transcriptional and Functional Levels: What Prospects for Cancer Therapy? Cancers (Basel) 2021; 13:2930. [PMID: 34208195 PMCID: PMC8230762 DOI: 10.3390/cancers13122930] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/03/2021] [Accepted: 06/08/2021] [Indexed: 01/07/2023] Open
Abstract
The RAD51 recombinase is a critical effector of Homologous Recombination (HR), which is an essential DNA repair mechanism for double-strand breaks. The RAD51 protein is recruited onto the DNA break by BRCA2 and forms homopolymeric filaments that invade the homologous chromatid and use it as a template for repair. RAD51 filaments are detectable by immunofluorescence as distinct foci in the cell nucleus, and their presence is a read out of HR proficiency. RAD51 is an essential gene, protecting cells from genetic instability. Its expression is low and tightly regulated in normal cells and, contrastingly, elevated in a large fraction of cancers, where its level of expression and activity have been linked with sensitivity to genotoxic treatment. In particular, BRCA-deficient tumors show reduced or obliterated RAD51 foci formation and increased sensitivity to platinum salt or PARP inhibitors. However, resistance to treatment sets in rapidly and is frequently based on a complete or partial restoration of RAD51 foci formation. Consequently, RAD51 could be a highly valuable therapeutic target. Here, we review the multiple levels of regulation that impact the transcription of the RAD51 gene, as well as the post-translational modifications that determine its expression level, recruitment on DNA damage sites and the efficient formation of homofilaments. Some of these regulation levels may be targeted and their impact on cancer cell survival discussed.
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Affiliation(s)
- Esin Orhan
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | | | - Imene Tabet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | - Claude Sardet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
| | - Charles Theillet
- IRCM, Institut de Recherche en Cancérologie de Montpellier U1194 INSERM, Université de Montpellier, 34090 Montpellier, France; (E.O.); (I.T.); (C.S.)
- ICM, Institut du Cancer de Montpellier, 34090 Montpellier, France;
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Klaric JA, Wüst S, Panier S. New Faces of old Friends: Emerging new Roles of RNA-Binding Proteins in the DNA Double-Strand Break Response. Front Mol Biosci 2021; 8:668821. [PMID: 34026839 PMCID: PMC8138124 DOI: 10.3389/fmolb.2021.668821] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/22/2021] [Indexed: 12/14/2022] Open
Abstract
DNA double-strand breaks (DSBs) are highly cytotoxic DNA lesions. To protect genomic stability and ensure cell homeostasis, cells mount a complex signaling-based response that not only coordinates the repair of the broken DNA strand but also activates cell cycle checkpoints and, if necessary, induces cell death. The last decade has seen a flurry of studies that have identified RNA-binding proteins (RBPs) as novel regulators of the DSB response. While many of these RBPs have well-characterized roles in gene expression, it is becoming increasingly clear that they also have non-canonical functions in the DSB response that go well beyond transcription, splicing and mRNA processing. Here, we review the current understanding of how RBPs are integrated into the cellular response to DSBs and describe how these proteins directly participate in signal transduction, amplification and repair at damaged chromatin. In addition, we discuss the implications of an RBP-mediated DSB response for genome instability and age-associated diseases such as cancer and neurodegeneration.
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Affiliation(s)
- Julie A Klaric
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Stas Wüst
- Max Planck Institute for Biology of Ageing, Cologne, Germany
| | - Stephanie Panier
- Max Planck Institute for Biology of Ageing, Cologne, Germany.,Cologne Cluster of Excellence in Cellular Stress Responses in Aging-Associated Diseases (CECAD) Research Center, University of Cologne, Cologne, Germany
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40
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DNA double-strand break repair: Putting zinc fingers on the sore spot. Semin Cell Dev Biol 2021; 113:65-74. [DOI: 10.1016/j.semcdb.2020.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 07/22/2020] [Accepted: 09/07/2020] [Indexed: 12/15/2022]
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Mouse Models for Deciphering the Impact of Homologous Recombination on Tumorigenesis. Cancers (Basel) 2021; 13:cancers13092083. [PMID: 33923105 PMCID: PMC8123484 DOI: 10.3390/cancers13092083] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 12/15/2022] Open
Abstract
Homologous recombination (HR) is a fundamental evolutionarily conserved process that plays prime role(s) in genome stability maintenance through DNA repair and through the protection and resumption of arrested replication forks. Many HR genes are deregulated in cancer cells. Notably, the breast cancer genes BRCA1 and BRCA2, two important HR players, are the most frequently mutated genes in familial breast and ovarian cancer. Transgenic mice constitute powerful tools to unravel the intricate mechanisms controlling tumorigenesis in vivo. However, the genes central to HR are essential in mammals, and their knockout leads to early embryonic lethality in mice. Elaborated strategies have been developed to overcome this difficulty, enabling one to analyze the consequences of HR disruption in vivo. In this review, we first briefly present the molecular mechanisms of HR in mammalian cells to introduce each factor in the HR process. Then, we present the different mouse models of HR invalidation and the consequences of HR inactivation on tumorigenesis. Finally, we discuss the use of mouse models for the development of targeted cancer therapies as well as perspectives on the future potential for understanding the mechanisms of HR inactivation-driven tumorigenesis in vivo.
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Yang C, Arnold AG, Catchings A, Rai V, Stadler ZK, Zhang L. The RAD51D c.82G>A (p.Val28Met) variant disrupts normal splicing and is associated with hereditary ovarian cancer. Breast Cancer Res Treat 2021; 185:869-877. [PMID: 33452952 DOI: 10.1007/s10549-020-06066-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 12/15/2020] [Indexed: 11/29/2022]
Abstract
PURPOSE Mutations in RAD51D are associated with a predisposition to primary ovarian, fallopian tube, and peritoneal carcinoma. Our study aims to characterize a RAD51D missense variant in a hereditary ovarian cancer family. METHODS The effects of the RAD51D c.82G>A (p.Val28Met) variant on mRNA splicing were evaluated and characterized using RT-PCR, cloning and DNA sequencing. RESULTS This variant completely disrupts normal splicing and results in the loss of 3'end of 5'UTR and the entire exon 1 (c.-86_c.82), which presumably leads to loss of the RAD51D protein. The RAD51D c.82G>A (p.Val28Met) variant is clinically significant and classified as likely pathogenic. CONCLUSIONS Our results indicate that the RAD51D c.82G>A (p.Val28Met) variant contributes to cancer predisposition through disruption of normal mRNA splicing. The identification of this variant in an individual affected with high-grade serous fallopian tube cancer suggests that the RAD51D variant may contribute to predisposition to the ovarian cancer in this family.
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Affiliation(s)
- Ciyu Yang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Angela G Arnold
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Amanda Catchings
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Vikas Rai
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Zsofia K Stadler
- Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Liying Zhang
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA. .,Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
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Lang GT, Shi JX, Huang L, Cao AY, Zhang CH, Song CG, Zhuang ZG, Hu X, Huang W, Shao ZM. Multiple cancer susceptible genes sequencing in BRCA-negative breast cancer with high hereditary risk. ANNALS OF TRANSLATIONAL MEDICINE 2020; 8:1417. [PMID: 33313162 PMCID: PMC7723566 DOI: 10.21037/atm-20-2999] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Hereditary factors contributed to breast cancer susceptibility. Low BRCA mutation prevalence was demonstrated in previous BRCA mutation screening in Chinese breast cancer patients. Multiple-gene sequencing may assist in discovering detrimental germline mutation in BRCA negative breast cancers. Methods A total of 384 Chinese subjects with any two of high-risk factors were recruited and screened by next-generation sequencing (NGS) for 30 cancer susceptible genes. Variants with a truncating, initiation codon or splice donor/acceptor effect, or with pathogenicity demonstrated in published literature were classified into pathogenic/likely-pathogenic mutations. Results In total, we acquired 39 (10.2%) patients with pathogenic/likely-pathogenic germline mutations, including one carrying two distinct mutations. Major mutant non-BRCA genes were MUTYH (n=11, 2.9%), PTCH1 (n=7, 1.8%), RET (n=6, 1.6%) and PALB2 (n=5, 1.3%). Other mutant genes included TP53 (n=3, 0.8%), RAD51D (n=2, 0.5%), CHEK2 (n=1, 0.3%), BRIP1 (n=1, 0.3%), CDH1 (n=1, 0.3%), MRE11 (n=1, 0.3%), RAD50 (n=1, 0.3%) and PALLD (n=1, 0.3%). A splicing germline mutation, MUTYH c.934-2A>G, was a hotspot (9/384, 2.3%) in Chinese breast cancer. Conclusions Among BRCA-negative breast cancer patients with high hereditary risk in China, 10.2% carried mutations in cancer associated susceptibility genes. MUTYH and PTCH1 had relatively high mutation rates (2.9% and 1.8%). Multigene testing contributes to understand genetic background of BRCA-negative breast cancer patients with high hereditary risk.
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Affiliation(s)
- Guan-Tian Lang
- Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Jin-Xiu Shi
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai (CHGC) and Shanghai Industrial Technology Institute (SITI), Shanghai, China
| | - Liang Huang
- Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - A-Yong Cao
- Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Chen-Hui Zhang
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai (CHGC) and Shanghai Industrial Technology Institute (SITI), Shanghai, China
| | - Chuan-Gui Song
- Department of Breast Surgery, Affiliated Union Hospital, Fujian Medical University, Fuzhou, China
| | - Zhi-Gang Zhuang
- Department of Breast Surgery, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xin Hu
- Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wei Huang
- Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai (CHGC) and Shanghai Industrial Technology Institute (SITI), Shanghai, China
| | - Zhi-Ming Shao
- Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, China
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Starcher CL, Pay SL, Singh N, Yeh IJ, Bhandare SB, Su X, Huang X, Bey EA, Motea EA, Boothman DA. Targeting Base Excision Repair in Cancer: NQO1-Bioactivatable Drugs Improve Tumor Selectivity and Reduce Treatment Toxicity Through Radiosensitization of Human Cancer. Front Oncol 2020; 10:1575. [PMID: 32974194 PMCID: PMC7468503 DOI: 10.3389/fonc.2020.01575] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 07/21/2020] [Indexed: 01/23/2023] Open
Abstract
Ionizing radiation (IR) creates lethal DNA damage that can effectively kill tumor cells. However, the high dose required for a therapeutic outcome also damages healthy tissue. Thus, a therapeutic strategy with predictive biomarkers to enhance the beneficial effects of IR allowing a dose reduction without losing efficacy is highly desirable. NAD(P)H:quinone oxidoreductase 1 (NQO1) is overexpressed in the majority of recalcitrant solid tumors in comparison with normal tissue. Studies have shown that NQO1 can bioactivate certain quinone molecules (e.g., ortho-naphthoquinone and β-lapachone) to induce a futile redox cycle leading to the formation of oxidative DNA damage, hyperactivation of poly(ADP-ribose) polymerase 1 (PARP1), and catastrophic depletion of NAD+ and ATP, which culminates in cellular lethality via NAD+-Keresis. However, NQO1-bioactivatable drugs induce methemoglobinemia and hemolytic anemia at high doses. To circumvent this, NQO1-bioactivatable agents have been shown to synergize with PARP1 inhibitors, pyrimidine radiosensitizers, and IR. This therapeutic strategy allows for a reduction in the dose of the combined agents to decrease unwanted side effects by increasing tumor selectivity. In this review, we discuss the mechanisms of radiosensitization between NQO1-bioactivatable drugs and IR with a focus on the involvement of base excision repair (BER). This combination therapeutic strategy presents a unique tumor-selective and minimally toxic approach for targeting solid tumors that overexpress NQO1.
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Affiliation(s)
- Colton L Starcher
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - S Louise Pay
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Naveen Singh
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - I-Ju Yeh
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Snehal B Bhandare
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Xiaolin Su
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Xiumei Huang
- Department of Radiation Oncology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Erik A Bey
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Edward A Motea
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - David A Boothman
- Department of Biochemistry and Molecular Biology, IU Simon Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
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Zhang F, Shen Y, Miao C, Cao Y, Shi W, Du G, Tang D, Li Y, Luo Q, Cheng Z. OsRAD51D promotes homologous pairing and recombination by preventing nonhomologous interactions in rice meiosis. THE NEW PHYTOLOGIST 2020; 227:824-839. [PMID: 32275774 DOI: 10.1111/nph.16595] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 03/23/2020] [Indexed: 06/11/2023]
Abstract
Homologous recombination is carefully orchestrated to maintain genome integrity. RAD51D has been previously shown to be essential for double-strand break repair in mammalian somatic cells. However, the function of RAD51D during meiosis is largely unknown. Here, through detailed analyses of Osrad51d single and double mutants, we pinpoint the specific function of OsRAD51D in coordinating homologous pairing and recombination by preventing nonhomologous interactions during meiosis. OsRAD51D is associated with telomeres in both meiocytes and somatic cells. Loss of OsRAD51D leads to significant induction of nonhomologous pairing and chromosome entanglements, suggesting its role in suppressing nonhomologous interactions. The failed localization of OsRAD51 and OsDMC1 in Osrad51d, together with the genetic analysis of Osrad51d Osdmc1a Osdmc1b, indicates that OsRAD51D acts at a very early stage of homologous recombination. Observations from the Osrad51d pair1 and Osrad51d ku70 double mutants further demonstrate that nonhomologous interactions require double-strand break formation but do not depend on the KU70-mediated repair pathway. Moreover, the interplay between OsRAD51D and OsRAD51C indicates both conservation and divergence of their functions in meiosis. Altogether, this work reveals that OsRAD51D plays an essential role in the inhibition of nonhomologous connections, thus guaranteeing faithful pairing and recombination during meiosis.
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Affiliation(s)
- Fanfan Zhang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Yi Shen
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Chunbo Miao
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Yiwei Cao
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Wenqing Shi
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Guijie Du
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Ding Tang
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Yafei Li
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
| | - Qiong Luo
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Ministry of Education Key Laboratory of Agriculture Biodiversity for Plant Disease Management, Yunnan Agricultural University, Kunming, 650201, China
| | - Zhukuan Cheng
- State Key Lab of Plant Genomics, Institute of Genetics and Developmental Biology, Innovation Academy for Seed Design, Chinese Academy of Sciences, 100101, Beijing, China
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou, 225009, China
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Sequential role of RAD51 paralog complexes in replication fork remodeling and restart. Nat Commun 2020; 11:3531. [PMID: 32669601 PMCID: PMC7363682 DOI: 10.1038/s41467-020-17324-z] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 06/16/2020] [Indexed: 12/19/2022] Open
Abstract
Homologous recombination (HR) factors were recently implicated in DNA replication fork remodeling and protection. While maintaining genome stability, HR-mediated fork remodeling promotes cancer chemoresistance, by as-yet elusive mechanisms. Five HR cofactors – the RAD51 paralogs RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3 – recently emerged as crucial tumor suppressors. Albeit extensively characterized in DNA repair, their role in replication has not been addressed systematically. Here, we identify all RAD51 paralogs while screening for modulators of RAD51 recombinase upon replication stress. Single-molecule analysis of fork progression and architecture in isogenic cellular systems shows that the BCDX2 subcomplex restrains fork progression upon stress, promoting fork reversal. Accordingly, BCDX2 primes unscheduled degradation of reversed forks in BRCA2-defective cells, boosting genomic instability. Conversely, the CX3 subcomplex is dispensable for fork reversal, but mediates efficient restart of reversed forks. We propose that RAD51 paralogs sequentially orchestrate clinically relevant transactions at replication forks, cooperatively promoting fork remodeling and restart. Replication stress has been associated with transient remodelling of replication intermediates into reversed forks, followed by efficient fork restart. Here the authors systematically analyse the role of RAD51 paralogs in these transactions, providing insights on the mechanistic role of different complexes of these proteins.
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Abstract
Accurate DNA repair and replication are critical for genomic stability and cancer prevention. RAD51 and its gene family are key regulators of DNA fidelity through diverse roles in double-strand break repair, replication stress, and meiosis. RAD51 is an ATPase that forms a nucleoprotein filament on single-stranded DNA. RAD51 has the function of finding and invading homologous DNA sequences to enable accurate and timely DNA repair. Its paralogs, which arose from ancient gene duplications of RAD51, have evolved to regulate and promote RAD51 function. Underscoring its importance, misregulation of RAD51, and its paralogs, is associated with diseases such as cancer and Fanconi anemia. In this review, we focus on the mammalian RAD51 structure and function and highlight the use of model systems to enable mechanistic understanding of RAD51 cellular roles. We also discuss how misregulation of the RAD51 gene family members contributes to disease and consider new approaches to pharmacologically inhibit RAD51.
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Affiliation(s)
- Braulio Bonilla
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - Sarah R Hengel
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - McKenzie K Grundy
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
| | - Kara A Bernstein
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213, USA;
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Yang G, Dong K, Zhang Z, Zhang E, Liang B, Chen X, Huang Z. EXO1 Plays a Carcinogenic Role in Hepatocellular Carcinoma and is related to the regulation of FOXP3. J Cancer 2020; 11:4917-4932. [PMID: 32626539 PMCID: PMC7330697 DOI: 10.7150/jca.40673] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 05/29/2020] [Indexed: 12/21/2022] Open
Abstract
Exonuclease 1 (EXO1), a member of the RAD2 nuclease family, was first described as possessing 5' to 3' nuclease activity and 5' structure-specific endonuclease activity. Here, we show that EXO1 is significantly upregulated in HCC tumor tissues and that high EXO1 expression is significantly correlated with liver cirrhosis. We further demonstrate that EXO1 knockdown decreases proliferation and colony forming abilities of HCC cells in vitro and tumorigenicity in vivo, as well as decreases migration and invasive capabilities of HCC cells. Alternatively, EXO1 overexpression significantly increases the proliferation, colony forming ability, and migration and invasive capabilities of HCC cells in vitro. Additionally, we truncated a region upstream of the transcription start site (TSS) of EXO1 and used the region with the strongest transcriptional activity to predict that the transcription factor FOXP3 can bind to the EXO1 promoter. Bioinformatics analysis found that FOXP3 was positively correlated with EXO1 and luciferase reporter assays and RT-PCR confirmed that FOXP3 could enhance the transcriptional activity of EXO1. CCK-8 assays showed that depletion of FOXP3 further reduces cell proliferation ability after knocking down of EXO1 in vitro. Taken together, our findings indicate that EXO1 acts as an oncogene in HCC and its expression level is related to FOXP3 activity.
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Affiliation(s)
- Guang Yang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Keshuai Dong
- Department of Hepatobiliary and Laparoscopic Surgery, Renmin Hospital, Wuhan University, Hubei Key Laboratory of Digestive System Disease, Wuhan, China
| | - Zunyi Zhang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Erlei Zhang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Binyong Liang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoping Chen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhiyong Huang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Knadler C, Rolfsmeier M, Vallejo A, Haseltine C. Characterization of an archaeal recombinase paralog that exhibits novel anti-recombinase activity. Mutat Res 2020; 821:111703. [PMID: 32416400 DOI: 10.1016/j.mrfmmm.2020.111703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 04/01/2020] [Indexed: 01/31/2023]
Abstract
The process of homologous recombination is heavily dependent on the RecA family of recombinases for repair of DNA double-strand breaks. These recombinases are responsible for identifying homologies and forming heteroduplex DNA between substrate ssDNA and dsDNA templates, activities that are modified by various accessory factors. In this work we describe the biochemical functions of the SsoRal2 recombinase paralog from the crenarchaeon Sulfolobus solfataricus. We found that the SsoRal2 protein is a DNA-independent ATPase that, unlike the other S. solfataricus paralogs, does not bind either ss- or dsDNA. Instead, SsoRal2 alters the ssDNA binding activity of the SsoRadA recombinase in conjunction with another paralog, SsoRal1. In the presence of SsoRal1, SsoRal2 has a modest effect on strand invasion but effectively abrogates strand exchange activity. Taken together, these results indicate that SsoRal2 assists in nucleoprotein filament modulation and control of strand exchange in S. solfataricus.
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Affiliation(s)
- Corey Knadler
- Washington State University, Biotech/LifeSciences Rm 137, Pullman, 99164, United States
| | - Michael Rolfsmeier
- Washington State University, Biotech/LifeSciences Rm 137, Pullman, 99164, United States
| | - Antonia Vallejo
- Washington State University, Biotech/LifeSciences Rm 137, Pullman, 99164, United States
| | - Cynthia Haseltine
- Washington State University, Biotech/LifeSciences Rm 137, Pullman, 99164, United States.
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Kurihara T, Kouyama-Suzuki E, Satoga M, Li X, Badawi M, Thiha, Baig DN, Yanagawa T, Uemura T, Mori T, Tabuchi K. DNA repair protein RAD51 enhances the CRISPR/Cas9-mediated knock-in efficiency in brain neurons. Biochem Biophys Res Commun 2020; 524:621-628. [PMID: 32029273 DOI: 10.1016/j.bbrc.2020.01.132] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/22/2020] [Indexed: 10/25/2022]
Abstract
Gene knock-in using the CRISPR/Cas9 system can be achieved in a specific population of neurons in the mouse brain, by using in utero electroporation to introduce DNA fragments into neural progenitor cells. Using this strategy, we previously knocked-in the EGFP coding sequence into the N-terminal region of the β-actin gene specifically in the pyramidal neurons in layer 2/3 of the somatosensory cortex. However, the knock-in efficiency was less than 2% of the transfected neurons. In this study, we sought to improve the knock-in efficiency using this system. First, we varied the length of the homology arms of the β-actin donor template DNA, and found that the knock-in efficiency was increased to ∼14% by extending the length of the 5' and 3' homology arms to 1.6 kb and 2.0 kb, respectively. We then tested the effect of the DNA repair protein RAD51 and the knock-in efficiency was increased up to 2.5-fold when co-transfecting with two different β-actin and a camk2a targeting EGFP knock-in modules. The RAD51 overexpression did not alter the migration of developing neurons, density or morphology of the dendritic spines compared to those in neurons not transfected with RAD51. RAD51 expression will be useful for increasing the knock-in efficiency in neurons in vivo by CRISPR/Cas9-mediated homology directed repair (HDR).
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Affiliation(s)
- Taiga Kurihara
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Emi Kouyama-Suzuki
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Michiru Satoga
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Xue Li
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Moataz Badawi
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Thiha
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan
| | - Deeba Noreen Baig
- School of Life Sciences Forman Christian College (A Chartared University), Lahore, 54600, Pakistan
| | - Toru Yanagawa
- Department of Oral and Maxillofacial Surgery, Faculty of Medicine, University of Tsukuba, Ibaraki, 305-8575, Japan
| | - Takeshi Uemura
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan; Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Nagano, 390-8621, Japan
| | - Takuma Mori
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan; Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Nagano, 390-8621, Japan
| | - Katsuhiko Tabuchi
- Department of Molecular and Cellular Physiology, Institute of Medicine, Academic Assembly, Shinshu University, Nagano, 390-8621, Japan; Institute for Biomedical Sciences, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Nagano, 390-8621, Japan.
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