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Uhrig ME, Sharma N, Maxwell P, Gomez J, Selemenakis P, Mazin AV, Wiese C. Disparate requirements for RAD54L in replication fork reversal. Nucleic Acids Res 2024:gkae828. [PMID: 39315725 DOI: 10.1093/nar/gkae828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 09/05/2024] [Accepted: 09/13/2024] [Indexed: 09/25/2024] Open
Abstract
RAD54L is a DNA motor protein with multiple roles in homologous recombination DNA repair. In vitro, RAD54L was shown to also catalyze the reversal and restoration of model replication forks. In cells, however, little is known about how RAD54L may regulate the dynamics of DNA replication. Here, we show that RAD54L restrains the progression of replication forks and functions as a fork remodeler in human cancer cell lines and non-transformed cells. Analogous to HLTF, SMARCAL1 and FBH1, and consistent with a role in fork reversal, RAD54L decelerates fork progression in response to replication stress and suppresses the formation of replication-associated ssDNA gaps. Interestingly, loss of RAD54L prevents nascent strand DNA degradation in both BRCA1/2- and 53BP1-deficient cells, suggesting that RAD54L functions in both pathways of RAD51-mediated replication fork reversal. In the HLTF/SMARCAL1 pathway, RAD54L is critical, but its ability to catalyze branch migration is dispensable, indicative of its function downstream of HLTF/SMARCAL1. Conversely, in the FBH1 pathway, branch migration activity of RAD54L is essential, and FBH1 engagement is dependent on its concerted action with RAD54L. Collectively, our results reveal disparate requirements for RAD54L in two distinct RAD51-mediated fork reversal pathways, positing its potential as a future therapeutic target.
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Affiliation(s)
- Mollie E Uhrig
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Petey Maxwell
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Jordi Gomez
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Platon Selemenakis
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Alexander V Mazin
- Department of Biochemistry and Structural Biology, UT Health San Antonio, San Antonio, TX 78229, USA
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
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2
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Uhrig ME, Sharma N, Maxwell P, Selemenakis P, Mazin AV, Wiese C. Disparate requirements for RAD54L in replication fork reversal. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.26.550704. [PMID: 37546955 PMCID: PMC10402051 DOI: 10.1101/2023.07.26.550704] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
RAD54L is a DNA motor protein with multiple roles in homologous recombination DNA repair (HR). In vitro , RAD54L was shown to also catalyze the reversal and restoration of model replication forks. In cells, however, little is known about how RAD54L may regulate the dynamics of DNA replication. Here, we show that RAD54L restrains the progression of replication forks and functions as a fork remodeler in human cells. Analogous to HLTF, SMARCAL1, and FBH1, and consistent with a role in fork reversal, RAD54L decelerates fork progression in response to replication stress and suppresses the formation of replication-associated ssDNA gaps. Interestingly, loss of RAD54L prevents nascent strand DNA degradation in both BRCA1/2- and 53BP1-deficient cells, suggesting that RAD54L functions in both pathways of RAD51-mediated replication fork reversal. In the HLTF/SMARCAL1 pathway, RAD54L is critical, but its ability to catalyze branch migration is dispensable, indicative of its function downstream of HLTF/SMARCAL1. Conversely, in the FBH1 pathway, branch migration activity of RAD54L is essential, and FBH1 engagement is dependent on its concerted action with RAD54L. Collectively, our results reveal disparate requirements for RAD54L in two distinct RAD51-mediated fork reversal pathways, positing its potential as a future therapeutic target.
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3
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Ito M, Fujita Y, Shinohara A. Positive and negative regulators of RAD51/DMC1 in homologous recombination and DNA replication. DNA Repair (Amst) 2024; 134:103613. [PMID: 38142595 DOI: 10.1016/j.dnarep.2023.103613] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 12/26/2023]
Abstract
RAD51 recombinase plays a central role in homologous recombination (HR) by forming a nucleoprotein filament on single-stranded DNA (ssDNA) to catalyze homology search and strand exchange between the ssDNA and a homologous double-stranded DNA (dsDNA). The catalytic activity of RAD51 assembled on ssDNA is critical for the DNA-homology-mediated repair of DNA double-strand breaks in somatic and meiotic cells and restarting stalled replication forks during DNA replication. The RAD51-ssDNA complex also plays a structural role in protecting the regressed/reversed replication fork. Two types of regulators control RAD51 filament formation, stability, and dynamics, namely positive regulators, including mediators, and negative regulators, so-called remodelers. The appropriate balance of action by the two regulators assures genome stability. This review describes the roles of positive and negative RAD51 regulators in HR and DNA replication and its meiosis-specific homolog DMC1 in meiotic recombination. We also provide future study directions for a comprehensive understanding of RAD51/DMC1-mediated regulation in maintaining and inheriting genome integrity.
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Affiliation(s)
- Masaru Ito
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Yurika Fujita
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
| | - Akira Shinohara
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita, Osaka 565-0871, Japan.
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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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Kishore V, Gaiwala Sharma SS, Raghunand TR. Septum site placement in Mycobacteria - identification and characterisation of mycobacterial homologues of Escherichia coli MinD. MICROBIOLOGY (READING, ENGLAND) 2023; 169:001359. [PMID: 37526955 PMCID: PMC10482377 DOI: 10.1099/mic.0.001359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Accepted: 06/22/2023] [Indexed: 08/02/2023]
Abstract
A major virulence trait of Mycobacterium tuberculosis (M. tb) is its ability to enter a dormant state within its human host. Since cell division is intimately linked to metabolic shut down, understanding the mechanism of septum formation and its integration with other events in the division pathway is likely to offer clues to the molecular basis of dormancy. The M. tb genome lacks obvious homologues of several conserved cell division proteins, and this study was aimed at identifying and functionally characterising mycobacterial homologues of the E. coli septum site specification protein MinD (Ec MinD). Sequence homology based analyses suggested that the genomes of both M. tb and the saprophyte Mycobacterium smegmatis (M. smegmatis) encode two putative Ec MinD homologues - Rv1708/MSMEG_3743 and Rv3660c/ MSMEG_6171. Of these, Rv1708/MSMEG_3743 were found to be the true homologues, through complementation of the E. coli ∆minDE mutant HL1, overexpression studies, and structural comparisons. Rv1708 and MSMEG_3743 fully complemented the mini-cell phenotype of HL1, and over-expression of MSMEG_3743 in M. smegmatis led to cell elongation and a drastic decrease in c.f.u. counts, indicating its essentiality in cell-division. MSMEG_3743 displayed ATPase activity, consistent with its containing a conserved Walker A motif. Interaction of Rv1708 with the chromosome associated proteins ScpA and ParB, implied a link between its septum formation role, and chromosome segregation. Comparative structural analyses showed Rv1708 to be closer in similarity to Ec MinD than Rv3660c. In summary we identify Rv1708 and MSMEG_3743 to be homologues of Ec MinD, adding a critical missing piece to the mycobacterial cell division puzzle.
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Affiliation(s)
- Vimal Kishore
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Present address: National Centre for Cell Science (NCCS), NCCS Complex, University of Pune Campus, Pune University Rd, Ganeshkhind, Pune, 411007, India
| | - Sujata S. Gaiwala Sharma
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Present address: Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008, India
| | - Tirumalai R. Raghunand
- CSIR - Centre for Cellular and Molecular Biology, Uppal Road Hyderabad - 500007, India
- Academy of Scientific and Innovative Research, Ghaziabad, India
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Longo MA, Roy S, Chen Y, Tomaszowski KH, Arvai AS, Pepper JT, Boisvert RA, Kunnimalaiyaan S, Keshvani C, Schild D, Bacolla A, Williams GJ, Tainer JA, Schlacher K. RAD51C-XRCC3 structure and cancer patient mutations define DNA replication roles. Nat Commun 2023; 14:4445. [PMID: 37488098 PMCID: PMC10366140 DOI: 10.1038/s41467-023-40096-1] [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: 04/12/2023] [Accepted: 07/07/2023] [Indexed: 07/26/2023] Open
Abstract
RAD51C is an enigmatic predisposition gene for breast, ovarian, and prostate cancer. Currently, missing structural and related functional understanding limits patient mutation interpretation to homology-directed repair (HDR) function analysis. Here we report the RAD51C-XRCC3 (CX3) X-ray co-crystal structure with bound ATP analog and define separable RAD51C replication stability roles informed by its three-dimensional structure, assembly, and unappreciated polymerization motif. Mapping of cancer patient mutations as a functional guide confirms ATP-binding matching RAD51 recombinase, yet highlights distinct CX3 interfaces. Analyses of CRISPR/Cas9-edited human cells with RAD51C mutations combined with single-molecule, single-cell and biophysics measurements uncover discrete CX3 regions for DNA replication fork protection, restart and reversal, accomplished by separable functions in DNA binding and implied 5' RAD51 filament capping. Collective findings establish CX3 as a cancer-relevant replication stress response complex, show how HDR-proficient variants could contribute to tumor development, and identify regions to aid functional testing and classification of cancer mutations.
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Affiliation(s)
- Michael A Longo
- Department of Molecular & Cellular Oncology, UT MD Anderson Cancer Center, Houston, TX, USA
| | - Sunetra Roy
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA
| | - Yue Chen
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA
| | | | - Andrew S Arvai
- The Department of Integrative Structural & Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Jordan T Pepper
- Department of Biochemistry and Molecular Biology, Robson DNA Science Centre, Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Rebecca A Boisvert
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA
| | | | - Caezanne Keshvani
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA
| | - David Schild
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Albino Bacolla
- Department of Molecular & Cellular Oncology, UT MD Anderson Cancer Center, Houston, TX, USA
| | - Gareth J Williams
- Department of Biochemistry and Molecular Biology, Robson DNA Science Centre, Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
| | - John A Tainer
- Department of Molecular & Cellular Oncology, UT MD Anderson Cancer Center, Houston, TX, USA.
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA.
| | - Katharina Schlacher
- Department of Cancer Biology, UT MD Anderson Cancer Center, Houston, TX, USA.
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Franca MM, Condezo YB, Elzaiat M, Felipe-Medina N, Sánchez-Sáez F, Muñoz S, Sainz-Urruela R, Martín-Hervás MR, García-Valiente R, Sánchez-Martín MA, Astudillo A, Mendez J, Llano E, Veitia RA, Mendonca BB, Pendás AM. A truncating variant of RAD51B associated with primary ovarian insufficiency provides insights into its meiotic and somatic functions. Cell Death Differ 2022; 29:2347-2361. [PMID: 35624308 PMCID: PMC9751091 DOI: 10.1038/s41418-022-01021-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/31/2023] Open
Abstract
Primary ovarian insufficiency (POI) causes female infertility by abolishing normal ovarian function. Although its genetic etiology has been extensively investigated, most POI cases remain unexplained. Using whole-exome sequencing, we identified a homozygous variant in RAD51B -(c.92delT) in two sisters with POI. In vitro studies revealed that this variant leads to translation reinitiation at methionine 64. Here, we show that this is a pathogenic hypomorphic variant in a mouse model. Rad51bc.92delT/c.92delT mice exhibited meiotic DNA repair defects due to RAD51 and HSF2BP/BMRE1 accumulation in the chromosome axes leading to a reduction in the number of crossovers. Interestingly, the interaction of RAD51B-c.92delT with RAD51C and with its newly identified interactors RAD51 and HELQ was abrogated or diminished. Repair of mitomycin-C-induced chromosomal aberrations was impaired in RAD51B/Rad51b-c.92delT human and mouse somatic cells in vitro and in explanted mouse bone marrow cells. Accordingly, Rad51b-c.92delT variant reduced replication fork progression of patient-derived lymphoblastoid cell lines and pluripotent reprogramming efficiency of primary mouse embryonic fibroblasts. Finally, Rad51bc.92delT/c.92delT mice displayed increased incidence of pituitary gland hyperplasia. These results provide new mechanistic insights into the role of RAD51B not only in meiosis but in the maintenance of somatic genome stability.
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Affiliation(s)
- Monica M Franca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42 and SELA, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brasil
- Section of Endocrinology Diabetes and Metabolism, Department of Medicine, The University of Chicago, Chicago, IL, USA
| | - Yazmine B Condezo
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Maëva Elzaiat
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France
| | - Natalia Felipe-Medina
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Fernando Sánchez-Sáez
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Sergio Muñoz
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Raquel Sainz-Urruela
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - M Rosario Martín-Hervás
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Rodrigo García-Valiente
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
| | - Manuel A Sánchez-Martín
- Departamento de Medicina, Universidad de Salamanca, Salamanca, Spain
- Transgenic Facility, Nucleus platform, Universidad de Salamanca, Salamanca, Spain
| | | | - Juan Mendez
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Melchor Fernández Almagro 3, E-28029, Madrid, Spain
| | - Elena Llano
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain
- Departamento de Fisiología y Farmacología, Universidad de Salamanca, Salamanca, Spain
| | - Reiner A Veitia
- Université Paris Cité, CNRS, Institut Jacques Monod, F-75013, Paris, France.
- Université Paris-Saclay and Institut François Jacob, Comissariat à l'Energie Atomique, Gif-sur-Yvette, France.
| | - Berenice B Mendonca
- Unidade de Endocrinologia do Desenvolvimento, Laboratório de Hormônios e Genética Molecular/LIM42 and SELA, Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (FMUSP), São Paulo, Brasil.
| | - Alberto M Pendás
- Molecular Mechanisms Program, Centro de Investigación del Cáncer and Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca), Salamanca, Spain.
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Selemenakis P, Sharma N, Uhrig ME, Katz J, Kwon Y, Sung P, Wiese C. RAD51AP1 and RAD54L Can Underpin Two Distinct RAD51-Dependent Routes of DNA Damage Repair via Homologous Recombination. Front Cell Dev Biol 2022; 10:866601. [PMID: 35652094 PMCID: PMC9149245 DOI: 10.3389/fcell.2022.866601] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 04/20/2022] [Indexed: 11/17/2022] Open
Abstract
Homologous recombination DNA repair (HR) is a complex DNA damage repair pathway and an attractive target of inhibition in anti-cancer therapy. To help guide the development of efficient HR inhibitors, it is critical to identify compensatory HR sub-pathways. In this study, we describe a novel synthetic interaction between RAD51AP1 and RAD54L, two structurally unrelated proteins that function downstream of the RAD51 recombinase in HR. We show that concomitant deletion of RAD51AP1 and RAD54L further sensitizes human cancer cell lines to treatment with olaparib, a Poly (adenosine 5′-diphosphate-ribose) polymerase inhibitor, to the DNA inter-strand crosslinking agent mitomycin C, and to hydroxyurea, which induces DNA replication stress. We also show that the RAD54L paralog RAD54B compensates for RAD54L deficiency, although, surprisingly, less extensively than RAD51AP1. These results, for the first time, delineate RAD51AP1- and RAD54L-dependent sub-pathways and will guide the development of inhibitors that target HR stimulators of strand invasion.
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Affiliation(s)
- Platon Selemenakis
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States.,Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO, United States
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Mollie E Uhrig
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Jeffrey Katz
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Youngho Kwon
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
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Structural, molecular, and functional insights into Schlafen proteins. EXPERIMENTAL & MOLECULAR MEDICINE 2022; 54:730-738. [PMID: 35768579 PMCID: PMC9256597 DOI: 10.1038/s12276-022-00794-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 04/08/2022] [Accepted: 04/14/2022] [Indexed: 11/30/2022]
Abstract
Schlafen (SLFN) genes belong to a vertebrate gene family encoding proteins with high sequence homology. However, each SLFN is functionally divergent and differentially expressed in various tissues and species, showing a wide range of expression in cancer and normal cells. SLFNs are involved in various cellular and tissue-specific processes, including DNA replication, proliferation, immune and interferon responses, viral infections, and sensitivity to DNA-targeted anticancer agents. The fundamental molecular characteristics of SLFNs and their structures are beginning to be elucidated. Here, we review recent structural insights into the N-terminal, middle and C-terminal domains (N-, M-, and C-domains, respectively) of human SLFNs and discuss the current understanding of their biological roles. We review the distinct molecular activities of SLFN11, SLFN5, and SLFN12 and the relevance of SLFN11 as a predictive biomarker in oncology. The diverse roles that Schlafen family proteins play in cell proliferation, immune modulation, and other biological processes make them promising targets for treating and tracking diseases, especially cancer. Ukhyun Jo and Yves Pommier from the National Cancer Institute in Bethesda, USA, review the molecular characteristics and structural features of Schlafen proteins. These proteins take their name from the German word for “sleep”, as the first described Schlafen proteins caused cells to stop dividing, although later reports found that related members of the same protein family serve myriad cellular functions, including in the regulation of DNA replication. A better understanding of Schlafen proteins could open up new avenues in cancer management, for instance, diagnostics that monitor activity levels of one such protein, SLFN11, could help oncologists predict how well patients might respond to anti-cancer therapies.
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10
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Zhou X, Li S, Yang X. The DcPS1 cooperates with OSDLa during pollen development and 2n gamete production in carnation meiosis. BMC PLANT BIOLOGY 2022; 22:259. [PMID: 35610560 PMCID: PMC9128087 DOI: 10.1186/s12870-022-03648-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 05/09/2022] [Indexed: 05/31/2023]
Abstract
BACKGROUND Deciphering the mechanisms of meiosis has important implications for potential applications in plant breeding programmes and species evolution. However, the process of meiosis is poorly understood in carnation, which is famous for its cut flowers. RESULTS We report that Dianthus caryophyllus parallel spindle 1 (DcPS1) regulates omission of second division like a (OSDLa) during pollen development and 2n gamete production in carnation meiosis. In DcPS1 and OSDLa RNAi lines, an absence of the second meiotic division and the abnormal orientation of spindles at meiosis II might be the main reason for dyad/triad formation, resulting in unreduced gametes. We also found that carnation OSDLa interacted with DcPS1 and DcRAD51D. In the DcPS1 RNAi lines, a decrease in OSDLa and DcRAD51D expression was observed. In the OSDLa RNAi lines, a decrease in DcPS1 and DcRAD51D expression was also observed. We propose that DcPS1 regulates OSDLa expression, allowing entry into meiosis II and the proper orientation of the metaphase II spindle in meiosis II. We also propose that OSDLa regulates DcRAD51D expression, allowing for homologous recombination. CONCLUSIONS These results suggest a critical role for DcPS1 and OSDLa in diplogamete production during meiosis and open a new pathway for meiosis-related studies.
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Affiliation(s)
- Xuhong Zhou
- Office of Science and Technology, Yunnan University of Chinese Medicine, 1076 Yuhua Road, Chenggong, Kunming, Yunnan, 650500, PR China.
- Flower Research Institute, Yunnan Academy of Agricultural Sciences, National Engineering Research Center for Ornamental Horticulture, 2238 Beijing Road, Kunming, Yunnan, 650205, PR China.
| | - Shuying Li
- Flower Research Institute, Yunnan Academy of Agricultural Sciences, National Engineering Research Center for Ornamental Horticulture, 2238 Beijing Road, Kunming, Yunnan, 650205, PR China
| | - Xiaomi Yang
- Office of Science and Technology, Yunnan University of Chinese Medicine, 1076 Yuhua Road, Chenggong, Kunming, Yunnan, 650500, PR China
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11
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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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12
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Boni J, Idani A, Roca C, Feliubadaló L, Tomiak E, Weber E, Foulkes WD, Orthwein A, El Haffaf Z, Lazaro C, Rivera B. A decade of RAD51C and RAD51D germline variants in cancer. Hum Mutat 2021; 43:285-298. [PMID: 34923718 DOI: 10.1002/humu.24319] [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: 08/25/2021] [Revised: 12/08/2021] [Accepted: 12/15/2021] [Indexed: 11/12/2022]
Abstract
Defects in DNA repair genes have been extensively associated with cancer susceptibility. Germline pathogenic variants (GPV) in genes involved in homologous recombination repair pathways predispose to cancers arising mainly in the breast and ovary, but also other tissues. The RAD51 paralogs RAD51C and RAD51D were included in this group 10 years ago when germline variants were associated with non-BRCA1/2 familial ovarian cancer. Here, we have reviewed the landscape of RAD51C and RAD51D germline variants in cancer reported in the literature during the last decade, integrating this list with variants identified by in-house patient screening. A comprehensive catalog of 341 variants that have been classified applying ACMG/AMP criteria has been generated pinpointing the existence of recurrent variants in both genes. Recurrent variants have been extensively discussed compiling data on population frequencies and functional characterization if available, highlighting variants that have not been fully characterized yet to properly establish their pathogenicity. Finally, we have complemented this data with relevant information regarding the conservation of mutated residues among RAD51 paralogs and modeling of putative hotspot areas, which contributes to generating an exhaustive update on these two cancer predisposition genes.
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Affiliation(s)
- Jacopo Boni
- Program in Molecular Mechanisms and Experimental Therapy in Oncology (Oncobell), Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Aida Idani
- Program in Molecular Mechanisms and Experimental Therapy in Oncology (Oncobell), Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Carla Roca
- Program in Molecular Mechanisms and Experimental Therapy in Oncology (Oncobell), Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Lidia Feliubadaló
- Hereditary Cancer Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Eva Tomiak
- Department of Genetics, University of Ottawa, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - Evan Weber
- Division of Medical Genetics, Department of Specialized Medicine, McGill University Health Centre, Quebec, Montreal, Canada
| | - William D Foulkes
- Division of Medical Genetics, Department of Specialized Medicine, McGill University Health Centre, Quebec, Montreal, Canada.,Gerald Bronfman Department of Oncology, McGill University Montreal, Montreal, Quebec, Canada.,Department of Human Genetics, McGill University Montreal, Montreal, Quebec, Canada.,Cancer Research Axis, Lady Davis Institute, Jewish General Hospital, Quebec, Montreal, Canada
| | - Alexandre Orthwein
- Gerald Bronfman Department of Oncology, McGill University Montreal, Montreal, Quebec, Canada.,Cancer Research Axis, Lady Davis Institute, Jewish General Hospital, Quebec, Montreal, Canada
| | - Zaki El Haffaf
- Division of Genetics, Department of Medicine, Research Center, Centre Hospitalier de l'Université de Montréal (CRCHUM), Quebec, Montreal, Canada
| | - Conxi Lazaro
- Program in Molecular Mechanisms and Experimental Therapy in Oncology (Oncobell), Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain.,Hereditary Cancer Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Barbara Rivera
- Program in Molecular Mechanisms and Experimental Therapy in Oncology (Oncobell), Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain.,Hereditary Cancer Program, Catalan Institute of Oncology, Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain.,Gerald Bronfman Department of Oncology, McGill University Montreal, Montreal, Quebec, Canada.,Cancer Research Axis, Lady Davis Institute, Jewish General Hospital, Quebec, Montreal, Canada
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13
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Bueno-Martínez E, Sanoguera-Miralles L, Valenzuela-Palomo A, Lorca V, Gómez-Sanz A, Carvalho S, Allen J, Infante M, Pérez-Segura P, Lázaro C, Easton DF, Devilee P, Vreeswijk MPG, de la Hoya M, Velasco EA. RAD51D Aberrant Splicing in Breast Cancer: Identification of Splicing Regulatory Elements and Minigene-Based Evaluation of 53 DNA Variants. Cancers (Basel) 2021; 13:2845. [PMID: 34200360 PMCID: PMC8201001 DOI: 10.3390/cancers13112845] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 12/18/2022] Open
Abstract
RAD51D loss-of-function variants increase lifetime risk of breast and ovarian cancer. Splicing disruption is a frequent pathogenic mechanism associated with variants in susceptibility genes. Herein, we have assessed the splicing and clinical impact of splice-site and exonic splicing enhancer (ESE) variants identified through the study of ~113,000 women of the BRIDGES cohort. A RAD51D minigene with exons 2-9 was constructed in splicing vector pSAD. Eleven BRIDGES splice-site variants (selected by MaxEntScan) were introduced into the minigene by site-directed mutagenesis and tested in MCF-7 cells. The 11 variants disrupted splicing, collectively generating 25 different aberrant transcripts. All variants but one produced negligible levels (<3.4%) of the full-length (FL) transcript. In addition, ESE elements of the alternative exon 3 were mapped by testing four overlapping exonic microdeletions (≥30-bp), revealing an ESE-rich interval (c.202_235del) with critical sequences for exon 3 recognition that might have been affected by germline variants. Next, 26 BRIDGES variants and 16 artificial exon 3 single-nucleotide substitutions were also assayed. Thirty variants impaired splicing with variable amounts (0-65.1%) of the FL transcript, although only c.202G>A demonstrated a complete aberrant splicing pattern without the FL transcript. On the other hand, c.214T>C increased efficiency of exon 3 recognition, so only the FL transcript was detected (100%). In conclusion, 41 RAD51D spliceogenic variants (28 of which were from the BRIDGES cohort) were identified by minigene assays. We show that minigene-based mapping of ESEs is a powerful approach for identifying ESE hotspots and ESE-disrupting variants. Finally, we have classified nine variants as likely pathogenic according to ACMG/AMP-based guidelines, highlighting the complex relationship between splicing alterations and variant interpretation.
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Affiliation(s)
- Elena Bueno-Martínez
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Lara Sanoguera-Miralles
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Alberto Valenzuela-Palomo
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
| | - Víctor Lorca
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Alicia Gómez-Sanz
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Sara Carvalho
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Jamie Allen
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Mar Infante
- Cancer Genetics, Unidad de Excelencia Instituto de Biología y Genética Molecular (CSIC-UVa), 47003 Valladolid, Spain;
| | - Pedro Pérez-Segura
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Conxi Lázaro
- Hereditary Cancer Program, Catalan Institute of Oncology, IDIBELL and CIBERONC, 08908 Hospitalet de Llobregat, Spain;
| | - Douglas F. Easton
- Centre for Cancer Genetic Epidemiology, Department of Public Health and Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; (S.C.); (J.A.); (D.F.E.)
| | - Peter Devilee
- Department of Human Genetics, Leiden University Medical Center, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Maaike P. G. Vreeswijk
- Department of Human Genetics, Leiden University Medical Center, 2300RC Leiden, The Netherlands; (P.D.); (M.P.G.V.)
| | - Miguel de la Hoya
- Molecular Oncology Laboratory CIBERONC, IdISSC (Instituto de Investigación Sanitaria del Hospital Clínico San Carlos), Hospital Clinico San Carlos, 28040 Madrid, Spain; (V.L.); (A.G.-S.); (P.P.-S.)
| | - Eladio A. Velasco
- Splicing and Genetic Susceptibility to Cancer Laboratory, Unidad de Excelencia Instituto de Biología y Genética Molecular, Consejo Superior de Investigaciones Científicas (CSIC-UVa), 47003 Valladolid, Spain; (E.B.-M.); (L.S.-M.); (A.V.-P.)
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14
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Pires E, Sharma N, Selemenakis P, Wu B, Huang Y, Alimbetov DS, Zhao W, Wiese C. RAD51AP1 mediates RAD51 activity through nucleosome interaction. J Biol Chem 2021; 297:100844. [PMID: 34058198 PMCID: PMC8233230 DOI: 10.1016/j.jbc.2021.100844] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 05/18/2021] [Accepted: 05/26/2021] [Indexed: 10/31/2022] Open
Abstract
RAD51-associated protein 1 (RAD51AP1) is a key protein in the homologous recombination (HR) DNA repair pathway. Loss of RAD51AP1 leads to defective HR, genome instability, and telomere erosion. RAD51AP1 physically interacts with the RAD51 recombinase and promotes RAD51-mediated capture of donor DNA, synaptic complex assembly, and displacement-loop formation when tested with nucleosome-free DNA substrates. In cells, however, DNA is packaged into chromatin, posing an additional barrier to the complexities of the HR reaction. In this study, we show that RAD51AP1 binds to nucleosome core particles (NCPs), the minimum basic unit of chromatin in which approximately two superhelical turns of 147 bp double-stranded DNA are wrapped around one histone octamer with no free DNA ends remaining. We identified a C-terminal region in RAD51AP1, including its previously mapped DNA-binding domain, as critical for mediating the association between RAD51AP1 and both the NCP and the histone octamer. Using in vitro surrogate assays of HR activity, we show that RAD51AP1 is capable of promoting duplex DNA capture and initiating joint-molecule formation with the NCP and chromatinized template DNA, respectively. Together, our results suggest that RAD51AP1 directly assists in the RAD51-mediated search for donor DNA in chromatin. We present a model, in which RAD51AP1 anchors the DNA template through affinity for its nucleosomes to the RAD51-ssDNA nucleoprotein filament.
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Affiliation(s)
- Elena Pires
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA; Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, Colorado, USA
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Platon Selemenakis
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA; Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, Colorado, USA
| | - Bo Wu
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Yuxin Huang
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Dauren S Alimbetov
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Weixing Zhao
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, Texas, USA
| | - Claudia Wiese
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA.
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15
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Maranon DG, Sharma N, Huang Y, Selemenakis P, Wang M, Altina N, Zhao W, Wiese C. NUCKS1 promotes RAD54 activity in homologous recombination DNA repair. J Cell Biol 2021; 219:152064. [PMID: 32876692 PMCID: PMC7659731 DOI: 10.1083/jcb.201911049] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 05/04/2020] [Accepted: 06/18/2020] [Indexed: 12/13/2022] Open
Abstract
NUCKS1 (nuclear ubiquitous casein kinase and cyclin-dependent kinase substrate 1) is a chromatin-associated, vertebrate-specific, and multifunctional protein with a role in DNA damage signaling and repair. Previously, we have shown that NUCKS1 helps maintain homologous recombination (HR) DNA repair in human cells and functions as a tumor suppressor in mice. However, the mechanisms by which NUCKS1 positively impacts these processes had remained unclear. Here, we show that NUCKS1 physically and functionally interacts with the DNA motor protein RAD54. Upon exposure of human cells to DNA-damaging agents, NUCKS1 controls the resolution of RAD54 foci. In unperturbed cells, NUCKS1 prevents RAD54's inappropriate engagement with RAD51AP1. In vitro, NUCKS1 stimulates the ATPase activity of RAD54 and the RAD51-RAD54-mediated strand invasion step during displacement loop formation. Taken together, our data demonstrate that the NUCKS1 protein is an important new regulator of the spatiotemporal events in HR.
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Affiliation(s)
- David G Maranon
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO
| | - Neelam Sharma
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO
| | - Yuxin Huang
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX
| | - Platon Selemenakis
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO.,Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO
| | - Meiling Wang
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX
| | - Noelia Altina
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO.,Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO
| | - Weixing Zhao
- Department of Biochemistry and Structural Biology, University of Texas Health San Antonio, San Antonio, TX
| | - Claudia Wiese
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO.,Cell and Molecular Biology Graduate Program, Colorado State University, Fort Collins, CO
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16
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Wappenschmidt B, Hauke J, Faust U, Niederacher D, Wiesmüller L, Schmidt G, Groß E, Gehrig A, Sutter C, Ramser J, Rump A, Arnold N, Meindl A. Criteria of the German Consortium for Hereditary Breast and Ovarian Cancer for the Classification of Germline Sequence Variants in Risk Genes for Hereditary Breast and Ovarian Cancer. Geburtshilfe Frauenheilkd 2020; 80:410-429. [PMID: 32322110 PMCID: PMC7174002 DOI: 10.1055/a-1110-0909] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 01/28/2020] [Accepted: 01/29/2020] [Indexed: 12/14/2022] Open
Abstract
More than ten years ago, the German Consortium for Hereditary Breast and Ovarian Cancer (GC-HBOC) set up a panel of experts (VUS Task Force) which was tasked with reviewing the classifications of genetic variants reported by individual centres of the GC-HBOC to the central database in Leipzig and reclassifying them, where necessary, based on the most recent data. When it evaluates variants, the VUS Task Force must arrive at a consensus. The resulting classifications are recorded in a central database where they serve as a basis for ensuring the consistent evaluation of previously known and newly identified variants in the different centres of the GC-HBOC. The standardised VUS evaluation by the VUS Task Force is a key element of the recall system which has also been set up by the GC-HBOC. The system will be used to pass on information to families monitored and managed by GC-HBOC centres in the event that previously classified variants are reclassified based on new information. The evaluation algorithm of the VUS Task Force was compiled using internationally established assessment methods (IARC, ACMG, ENIGMA) and is presented here together with the underlying evaluation criteria used to arrive at the classification decision using a flow chart. In addition, the characteristics and special features of specific individual risk genes associated with breast and/or ovarian cancer are discussed in separate subsections. The URLs of relevant databases have also been included together with extensive literature references to provide additional information and cover the scope and dynamism of the current state of knowledge on the evaluation of genetic variants. In future, if criteria are updated based on new information, the update will be published on the website of the GC-HBOC (
https://www.konsortium-familiaerer-brustkrebs.de/
).
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Affiliation(s)
- Barbara Wappenschmidt
- Zentrum familiärer Brust- und Eierstockkrebs, Universitätsklinikum Köln, Köln, Germany
| | - Jan Hauke
- Zentrum familiärer Brust- und Eierstockkrebs, Universitätsklinikum Köln, Köln, Germany
| | - Ulrike Faust
- Institut für Medizinische Genetik und Angewandte Genomik, Universität Tübingen, Tübingen, Germany
| | - Dieter Niederacher
- Klinik für Frauenheilkunde und Geburtshilfe, Universitätsklinikum Düsseldorf, Düsseldorf, Germany
| | - Lisa Wiesmüller
- Frauenklinik, Sektion Gynäkologische Onkologie, Uniklinik Ulm, Ulm, Germany
| | - Gunnar Schmidt
- Institut für Humangenetik, Medizinische Hochschule Hannover, Hannover, Germany
| | - Evi Groß
- Klinik und Poliklinik für Frauenheilkunde und Geburtshilfe, Klinikum der Universität München, Campus Großhadern, München, Germany
| | - Andrea Gehrig
- Institut für Humangenetik, Universität Würzburg, Würzburg, Germany
| | - Christian Sutter
- Institut für Humangenetik, Universität Heidelberg, Heidelberg, Germany
| | - Juliane Ramser
- Frauenklinik der Technischen Universität München, Klinikum rechts der Isar, München, Germany
| | - Andreas Rump
- Institut für klinische Genetik, Technische Universität Dresden, Dresden, Germany
| | - Norbert Arnold
- Universitätsklinikum Kiel, Klinik für Gynäkologie und Geburtshilfe, Kiel, Germany.,Institut für Klinische Molekularbiologie, Universitätsklinikum Kiel, Kiel, Germany
| | - Alfons Meindl
- Klinik und Poliklinik für Frauenheilkunde und Geburtshilfe, Klinikum der Universität München, Campus Großhadern, München, Germany.,Frauenklinik der Technischen Universität München, Klinikum rechts der Isar, München, Germany
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17
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Garcin EB, Gon S, Sullivan MR, Brunette GJ, Cian AD, Concordet JP, Giovannangeli C, Dirks WG, Eberth S, Bernstein KA, Prakash R, Jasin M, Modesti M. Differential Requirements for the RAD51 Paralogs in Genome Repair and Maintenance in Human Cells. PLoS Genet 2019; 15:e1008355. [PMID: 31584931 PMCID: PMC6795472 DOI: 10.1371/journal.pgen.1008355] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 10/16/2019] [Accepted: 08/07/2019] [Indexed: 12/16/2022] Open
Abstract
Deficiency in several of the classical human RAD51 paralogs [RAD51B, RAD51C, RAD51D, XRCC2 and XRCC3] is associated with cancer predisposition and Fanconi anemia. To investigate their functions, isogenic disruption mutants for each were generated in non-transformed MCF10A mammary epithelial cells and in transformed U2OS and HEK293 cells. In U2OS and HEK293 cells, viable ablated clones were readily isolated for each RAD51 paralog; in contrast, with the exception of RAD51B, RAD51 paralogs are cell-essential in MCF10A cells. Underlining their importance for genomic stability, mutant cell lines display variable growth defects, impaired sister chromatid recombination, reduced levels of stable RAD51 nuclear foci, and hyper-sensitivity to mitomycin C and olaparib, with the weakest phenotypes observed in RAD51B-deficient cells. Altogether these observations underscore the contributions of RAD51 paralogs in diverse DNA repair processes, and demonstrate essential differences in different cell types. Finally, this study will provide useful reagents to analyze patient-derived mutations and to investigate mechanisms of chemotherapeutic resistance deployed by cancers.
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Affiliation(s)
- Edwige B. Garcin
- Cancer Research Center of Marseille; CNRS; Inserm; Institut Paoli-Calmettes; Aix-Marseille Université, Marseille, France
| | - Stéphanie Gon
- Cancer Research Center of Marseille; CNRS; Inserm; Institut Paoli-Calmettes; Aix-Marseille Université, Marseille, France
| | - Meghan R. Sullivan
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine and UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania, United States of America
| | - Gregory J. Brunette
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine and UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania, United States of America
| | - Anne De Cian
- Museum National d'Histoire Naturelle, Inserm U1154, CNRS UMR 7196, Sorbonne Universités, Paris, France
| | - Jean-Paul Concordet
- Museum National d'Histoire Naturelle, Inserm U1154, CNRS UMR 7196, Sorbonne Universités, Paris, France
| | - Carine Giovannangeli
- Museum National d'Histoire Naturelle, Inserm U1154, CNRS UMR 7196, Sorbonne Universités, Paris, France
| | - Wilhelm G. Dirks
- Department of Human and Animal Cell Lines, Leibniz-Institute DSMZ-German, Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Sonja Eberth
- Department of Human and Animal Cell Lines, Leibniz-Institute DSMZ-German, Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Kara A. Bernstein
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine and UPMC Hillman Cancer Center, Pittsburgh, Pennsylvania, United States of America
| | - Rohit Prakash
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, United States of America
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York, United States of America
| | - Mauro Modesti
- Cancer Research Center of Marseille; CNRS; Inserm; Institut Paoli-Calmettes; Aix-Marseille Université, Marseille, France
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18
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Jordan MR, Wang J, Weiss A, Skaar EP, Capdevila DA, Giedroc DP. Mechanistic Insights into the Metal-Dependent Activation of Zn II-Dependent Metallochaperones. Inorg Chem 2019; 58:13661-13672. [PMID: 31247880 DOI: 10.1021/acs.inorgchem.9b01173] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Members of the COG0523 subfamily of candidate GTPase metallochaperones function in bacterial transition-metal homeostasis, but the nature of the cognate metal, mechanism of metal transfer, and identification of target protein(s) for metal delivery remain open questions. Here, we explore the multifunctionality of members of the subfamily linked to delivering ZnII to apoprotein targets under conditions of host-imposed transition-metal depletion. We examine two zinc-uptake repressor (Zur)-regulated COG0523 family members, each from a major human pathogen, Acinetobacter baumannii (AbZigA) and Staphylococcus aureus (SaZigA), in an effort to develop a model for ZnII metallochaperone activity. ZnII chelator competition experiments reveal one high-affinity (KZn1 ≈ 1010-1011 M-1) metal-binding site in each GTPase, while AbZigA and SaZigA are characterized by an additional one and two (lower-affinity) metal-binding sites, respectively. CoII titrations reveal that both metallochaperones have similar electronic absorption characteristics that indicate the presence of two tetrahedral metal coordination sites. High-affinity metal binding at the CXCC motif activates the GTPase activity of both enzymes, with ZnII more effective than CoII. Both GTPases bind the product, GDP, more tightly in the apoprotein than the ZnII-bound state and exhibit what is best described as a "locked" conformation around the GTP substrate. Negative thermodynamic linkage is observed between nucleotide binding and metal binding, leading to a new mechanistic model for COG0523-catalyzed metal delivery.
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Affiliation(s)
| | | | - Andy Weiss
- Department of Pathology, Microbiology, and Immunology , Vanderbilt University Medical Center , Nashville , Tennessee 37232 , United States
| | - Eric P Skaar
- Department of Pathology, Microbiology, and Immunology , Vanderbilt University Medical Center , Nashville , Tennessee 37232 , United States
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19
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Hartmann M, Kohl KP, Sekelsky J, Hatkevich T. Meiotic MCM Proteins Promote and Inhibit Crossovers During Meiotic Recombination. Genetics 2019; 212:461-468. [PMID: 31028111 PMCID: PMC6553819 DOI: 10.1534/genetics.119.302221] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 04/22/2019] [Indexed: 01/29/2023] Open
Abstract
Crossover formation as a result of meiotic recombination is vital for the proper segregation of homologous chromosomes at the end of meiosis I. In many organisms, crossovers are generated through two crossover pathways: Class I and Class II. To ensure accurate crossover formation, meiosis-specific protein complexes regulate the degree to which each pathway is used. One such complex is the mei-mini-chromosome maintenance (MCM) complex, which contains MCM and MCM-like proteins REC (ortholog of Mcm8), MEI-217, and MEI-218. The mei-MCM complex genetically promotes Class I crossovers and inhibits Class II crossovers in Drosophila, but it is unclear how individual mei-MCM proteins contribute to crossover regulation. In this study, we perform genetic analyses to understand how specific regions and motifs of mei-MCM proteins contribute to Class I and II crossover formation, and distribution. Our analyses show that the long, disordered N-terminus of MEI-218 is dispensable for crossover formation, and that mutations that disrupt REC's Walker A and B motifs differentially affect Class I and Class II crossover formation. In rec Walker A mutants, Class I crossovers exhibit no change but Class II crossovers are increased. However, in rec Walker B mutants, Class I crossovers are severely impaired and Class II crossovers are increased. These results suggest that REC may form multiple complexes that exhibit differential REC-dependent ATP-binding and -hydrolyzing requirements. These results provide genetic insight into the mechanisms through which mei-MCM proteins promote Class I crossovers and inhibit Class II crossovers.
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Affiliation(s)
- Michaelyn Hartmann
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Kathryn P Kohl
- Department of Biology, Winthrop University, Rock Hill, South Carolina 29733
| | - Jeff Sekelsky
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina 27599
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
- Integrative Program in Biological and Genome Sciences, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Talia Hatkevich
- Curriculum in Genetics and Molecular Biology, University of North Carolina, Chapel Hill, North Carolina 27599
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20
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RAD51D splice variants and cancer-associated mutations reveal XRCC2 interaction to be critical for homologous recombination. DNA Repair (Amst) 2019; 76:99-107. [PMID: 30836272 DOI: 10.1016/j.dnarep.2019.02.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 02/15/2019] [Accepted: 02/15/2019] [Indexed: 12/14/2022]
Abstract
The proficiency of cancer cells to repair DNA double-strand breaks (DSBs) by homologous recombination (HR) is a key determinant in predicting response to targeted therapies such as PARP inhibitors. The RAD51 paralogs work as multimeric complexes and act downstream of BRCA1 to facilitate HR. Numerous epidemiological studies have linked RAD51 paralog mutations with hereditary cancer predisposition. Despite their substantial links to cancer, RAD51 paralog HR function has remained elusive. Here we identify isoform 1 as the functional isoform of RAD51D, whereas isoform 4 which has a large N-terminal deletion (including the Walker A motif), and isoform 6 which includes an alternate exon in the N-terminus, are non-functional. To determine the importance of this N-terminal region, we investigated the impact of cancer-associated mutations and SNPs in this variable RAD51D N-terminal region using yeast-2-hybrid and yeast-3-hybrid assays to screen for altered protein-protein interactions. We identified two cancer-associated mutations close to or within the Walker A motif (G96C and G107 V, respectively) that independently disrupt RAD51D interaction with XRCC2. We validated our yeast interaction data in human U2OS cells by co-immunoprecipitation and determined the impact of these mutations on HR-proficiency using a sister chromatid recombination reporter assay in a RAD51D knock-out cell line. Our investigation reveals that the interaction of RAD51D with XRCC2 is required for DSB repair. By characterizing the impact of cancer-associated mutations on RAD51D interactions, we aim to develop predictive models for therapeutic sensitivity and resistance in patients who harbor similar mutations in RAD51D.
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21
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Reilly NM, Yard BD, Pittman DL. Homologous Recombination-Mediated DNA Repair and Implications for Clinical Treatment of Repair Defective Cancers. Methods Mol Biol 2019; 1999:3-29. [PMID: 31127567 DOI: 10.1007/978-1-4939-9500-4_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Double-strand DNA breaks (DSBs) are generated by ionizing radiation and as intermediates during the processing of DNA, such as repair of interstrand cross-links and collapsed replication forks. These potentially deleterious DSBs are repaired primarily by the homologous recombination (HR) and nonhomologous end joining (NHEJ) DNA repair pathways. HR utilizes a homologous template to accurately restore damaged DNA, whereas NHEJ utilizes microhomology to join breaks in close proximity. The pathway available for DSB repair is dependent upon the cell cycle stage; for example, HR primarily functions during the S/G2 stages while NHEJ can repair DSBs at any cell cycle stage. Posttranslational modifications (PTMs) promote activity of specific pathways and subpathways through enzyme activation and precisely timed protein recruitment and degradation. This chapter provides an overview of PTMs occurring during DSB repair. In addition, clinical phenotypes associated with HR-defective cancers, such as mutational signatures used to predict response to poly(ADP-ribose) polymerase inhibitors, are discussed. Understanding these processes will provide insight into mechanisms of genome maintenance and likely identify targets and new avenues for therapeutic interventions.
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Affiliation(s)
- Nicole M Reilly
- Fondazione Piemontese per la Ricerca sul Cancro ONLUS, Candiolo, Italy
| | - Brian D Yard
- Department of Translational Hematology and Oncology Research, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Douglas L Pittman
- Department of Drug Discovery and Biomedical Sciences, College of Pharmacy, University of South Carolina, Columbia, SC, USA.
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22
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Rivera B, Di Iorio M, Frankum J, Nadaf J, Fahiminiya S, Arcand SL, Burk DL, Grapton D, Tomiak E, Hastings V, Hamel N, Wagener R, Aleynikova O, Giroux S, Hamdan FF, Dionne-Laporte A, Zogopoulos G, Rousseau F, Berghuis AM, Provencher D, Rouleau GA, Michaud JL, Mes-Masson AM, Majewski J, Bens S, Siebert R, Narod SA, Akbari MR, Lord CJ, Tonin PN, Orthwein A, Foulkes WD. Functionally Null RAD51D Missense Mutation Associates Strongly with Ovarian Carcinoma. Cancer Res 2017; 77:4517-4529. [PMID: 28646019 DOI: 10.1158/0008-5472.can-17-0190] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/23/2017] [Accepted: 06/06/2017] [Indexed: 11/16/2022]
Abstract
RAD51D is a key player in DNA repair by homologous recombination (HR), and RAD51D truncating variant carriers have an increased risk for ovarian cancer. However, the contribution of nontruncating RAD51D variants to cancer predisposition remains uncertain. Using deep sequencing and case-control genotyping studies, we show that in French Canadians, the missense RAD51D variant c.620C>T;p.S207L is highly prevalent and is associated with a significantly increased risk for ovarian high-grade serous carcinoma (HGSC; 3.8% cases vs. 0.2% controls). The frequency of the p.S207L variant did not significantly differ from that of controls in breast, endometrial, pancreas, or colorectal adenocarcinomas. Functionally, we show that this mutation impairs HR by disrupting the RAD51D-XRCC2 interaction and confers PARP inhibitor sensitivity. These results highlight the importance of a functional RAD51D-XRCC2 interaction to promote HR and prevent the development of HGSC. This study identifies c.620C>T;p.S207L as the first bona fide pathogenic RAD51D missense cancer susceptibility allele and supports the use of targeted PARP-inhibitor therapies in ovarian cancer patients carrying deleterious missense RAD51D variants. Cancer Res; 77(16); 4517-29. ©2017 AACR.
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Affiliation(s)
- Barbara Rivera
- Department of Human Genetics, McGill University, Montreal, Canada
- Lady Davis Institute, Montreal, Canada
| | - Massimo Di Iorio
- Department of Human Genetics, McGill University, Montreal, Canada
| | - Jessica Frankum
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, United Kingdom
| | - Javad Nadaf
- Department of Human Genetics, McGill University, Montreal, Canada
- Genome Quebec Innovation Centre, Montreal, Canada
| | - Somayyeh Fahiminiya
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Suzanna L Arcand
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
| | - David L Burk
- Department of Biochemistry, McGill University, Montreal, Canada
| | | | - Eva Tomiak
- Department of Genetics, University of Ottawa, Children's Hospital of Eastern Ontario, Canada
| | - Valerie Hastings
- Department of Genetics, University of Ottawa, Children's Hospital of Eastern Ontario, Canada
| | - Nancy Hamel
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Rabea Wagener
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Olga Aleynikova
- Department of pathology, Jewish General Hospital, Montreal, Canada
| | - Sylvie Giroux
- University of Laval and CHU Research Centre, Quebec; Canada
| | - Fadi F Hamdan
- CHU Sainte-Justine Research Center, Montreal, Canada
| | | | - George Zogopoulos
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
- The Goodman Cancer Research Centre, McGill University, Montreal, Canada
| | | | | | - Diane Provencher
- Centre de recherche du CHUM and Institut du cancer de Montréal, University of Montreal, Montreal, Canada
| | - Guy A Rouleau
- Montreal Neurological Institute, McGill University, Montreal, Canada
| | | | - Anne-Marie Mes-Masson
- Centre de recherche du CHUM and Institut du cancer de Montréal, University of Montreal, Montreal, Canada
| | - Jacek Majewski
- Department of Human Genetics, McGill University, Montreal, Canada
- Genome Quebec Innovation Centre, Montreal, Canada
| | - Susanne Bens
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Reiner Siebert
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Steven A Narod
- Dalla Lana School of Public Health, Toronto, Canada
- Women's College Hospital, Toronto, Canada
| | - Mohammad R Akbari
- Dalla Lana School of Public Health, Toronto, Canada
- Women's College Hospital, Toronto, Canada
| | - Christopher J Lord
- The CRUK Gene Function Laboratory and Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, United Kingdom
| | - Patricia N Tonin
- Department of Human Genetics, McGill University, Montreal, Canada
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
- Department of Medicine, McGill University, Montreal, Canada
| | - Alexandre Orthwein
- Lady Davis Institute, Montreal, Canada
- Department of Oncology, McGill University, Montreal, Canada
| | - William D Foulkes
- Department of Human Genetics, McGill University, Montreal, Canada.
- Lady Davis Institute, Montreal, Canada
- Cancer Research Program, The Research Institute of the McGill University Health Centre, Montreal, Canada
- Department of Medical Genetics, Research Institute, McGill University Health Centre, Montreal, Canada
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23
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Paths from DNA damage and signaling to genome rearrangements via homologous recombination. Mutat Res 2017; 806:64-74. [PMID: 28779875 DOI: 10.1016/j.mrfmmm.2017.07.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 07/21/2017] [Indexed: 12/31/2022]
Abstract
DNA damage is a constant threat to genome integrity. DNA repair and damage signaling networks play a central role maintaining genome stability, suppressing tumorigenesis, and determining tumor response to common cancer chemotherapeutic agents and radiotherapy. DNA double-strand breaks (DSBs) are critical lesions induced by ionizing radiation and when replication forks encounter damage. DSBs can result in mutations and large-scale genome rearrangements reflecting mis-repair by non-homologous end joining or homologous recombination. Ionizing radiation induces genetic change immediately, and it also triggers delayed events weeks or even years after exposure, long after the initial damage has been repaired or diluted through cell division. This review covers DNA damage signaling and repair pathways and cell fate following genotoxic insult, including immediate and delayed genome instability and cell survival/cell death pathways.
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24
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Allen CP, Hirakawa H, Nakajima NI, Moore S, Nie J, Sharma N, Sugiura M, Hoki Y, Araki R, Abe M, Okayasu R, Fujimori A, Nickoloff JA. Low- and High-LET Ionizing Radiation Induces Delayed Homologous Recombination that Persists for Two Weeks before Resolving. Radiat Res 2017; 188:82-93. [PMID: 28535128 DOI: 10.1667/rr14748.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Genome instability is a hallmark of cancer cells and dysregulation or defects in DNA repair pathways cause genome instability and are linked to inherited cancer predisposition syndromes. Ionizing radiation can cause immediate effects such as mutation or cell death, observed within hours or a few days after irradiation. Ionizing radiation also induces delayed effects many cell generations after irradiation. Delayed effects include hypermutation, hyper-homologous recombination, chromosome instability and reduced clonogenic survival (delayed death). Delayed hyperrecombination (DHR) is mechanistically distinct from delayed chromosomal instability and delayed death. Using a green fluorescent protein (GFP) direct repeat homologous recombination system, time-lapse microscopy and colony-based assays, we demonstrate that DHR increases several-fold in response to low-LET X rays and high-LET carbon-ion radiation. Time-lapse analyses of DHR revealed two classes of recombinants not detected in colony-based assays, including cells that recombined and then senesced or died. With both low- and high-LET radiation, DHR was evident during the first two weeks postirradiation, but resolved to background levels during the third week. The results indicate that the risk of radiation-induced genome destabilization via DHR is time limited, and suggest that there is little or no additional risk of radiation-induced genome instability mediated by DHR with high-LET radiation compared to low-LET radiation.
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Affiliation(s)
- Christopher P Allen
- a Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado
| | - Hirokazu Hirakawa
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Nakako Izumi Nakajima
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Sophia Moore
- a Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado
| | - Jingyi Nie
- a Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado
| | - Neelam Sharma
- a Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado
| | - Mayumi Sugiura
- c Division of Natural Sciences, Research Group of Biological Sciences, Nara Women's University, Nara, Japan
| | - Yuko Hoki
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Ryoko Araki
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Masumi Abe
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Ryuichi Okayasu
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Akira Fujimori
- b Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Chiba, Japan
| | - Jac A Nickoloff
- a Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, Colorado
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25
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CRISPR Technology Reveals RAD(51)-ical Mechanisms of Repair in Roundworms: An Educational Primer for Use with "Promotion of Homologous Recombination by SWS-1 in Complex with RAD-51 Paralogs in Caenorhabditis elegans". Genetics 2017; 204:883-891. [PMID: 28114101 DOI: 10.1534/genetics.116.195479] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The mechanisms cells use to maintain genetic fidelity via DNA repair and the accuracy of these processes have garnered interest from scientists engaged in basic research to clinicians seeking improved treatment for cancer patients. Despite the continued advances, many details of DNA repair are still incompletely understood. In addition, the inherent complexity of DNA repair processes, even at the most fundamental level, makes it a challenging topic. This primer is meant to assist both educators and students in using a recent paper, "Promotion of homologous recombination by SWS-1 in complex with RAD-51 paralogs in Caenorhabditis elegans," to understand mechanisms of DNA repair. The goals of this primer are to highlight and clarify several key techniques utilized, with special emphasis on the clustered, regularly interspaced, short palindromic repeats technique and the ways in which it has revolutionized genetics research, as well as to provide questions for deeper in-class discussion.
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26
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Parplys AC, Zhao W, Sharma N, Groesser T, Liang F, Maranon DG, Leung SG, Grundt K, Dray E, Idate R, Østvold AC, Schild D, Sung P, Wiese C. NUCKS1 is a novel RAD51AP1 paralog important for homologous recombination and genome stability. Nucleic Acids Res 2015; 43:9817-34. [PMID: 26323318 PMCID: PMC4787752 DOI: 10.1093/nar/gkv859] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 07/09/2015] [Accepted: 08/17/2015] [Indexed: 01/20/2023] Open
Abstract
NUCKS1 (nuclear casein kinase and cyclin-dependent kinase substrate 1) is a 27 kD chromosomal, vertebrate-specific protein, for which limited functional data exist. Here, we demonstrate that NUCKS1 shares extensive sequence homology with RAD51AP1 (RAD51 associated protein 1), suggesting that these two proteins are paralogs. Similar to the phenotypic effects of RAD51AP1 knockdown, we find that depletion of NUCKS1 in human cells impairs DNA repair by homologous recombination (HR) and chromosome stability. Depletion of NUCKS1 also results in greatly increased cellular sensitivity to mitomycin C (MMC), and in increased levels of spontaneous and MMC-induced chromatid breaks. NUCKS1 is critical to maintaining wild type HR capacity, and, as observed for a number of proteins involved in the HR pathway, functional loss of NUCKS1 leads to a slow down in DNA replication fork progression with a concomitant increase in the utilization of new replication origins. Interestingly, recombinant NUCKS1 shares the same DNA binding preference as RAD51AP1, but binds to DNA with reduced affinity when compared to RAD51AP1. Our results show that NUCKS1 is a chromatin-associated protein with a role in the DNA damage response and in HR, a DNA repair pathway critical for tumor suppression.
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Affiliation(s)
- Ann C Parplys
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Weixing Zhao
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Neelam Sharma
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Torsten Groesser
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Fengshan Liang
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - David G Maranon
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Stanley G Leung
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kirsten Grundt
- Department of Molecular Medicine, Institute of Basic Medical Science, University of Oslo, 0317 Oslo, Norway
| | - Eloïse Dray
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Rupa Idate
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Anne Carine Østvold
- Department of Molecular Medicine, Institute of Basic Medical Science, University of Oslo, 0317 Oslo, Norway
| | - David Schild
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Patrick Sung
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Claudia Wiese
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
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27
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Taylor MRG, Špírek M, Chaurasiya KR, Ward JD, Carzaniga R, Yu X, Egelman EH, Collinson LM, Rueda D, Krejci L, Boulton SJ. Rad51 Paralogs Remodel Pre-synaptic Rad51 Filaments to Stimulate Homologous Recombination. Cell 2015; 162:271-286. [PMID: 26186187 PMCID: PMC4518479 DOI: 10.1016/j.cell.2015.06.015] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/27/2015] [Accepted: 06/01/2015] [Indexed: 10/31/2022]
Abstract
Repair of DNA double strand breaks by homologous recombination (HR) is initiated by Rad51 filament nucleation on single-stranded DNA (ssDNA), which catalyzes strand exchange with homologous duplex DNA. BRCA2 and the Rad51 paralogs are tumor suppressors and critical mediators of Rad51. To gain insight into Rad51 paralog function, we investigated a heterodimeric Rad51 paralog complex, RFS-1/RIP-1, and uncovered the molecular basis by which Rad51 paralogs promote HR. Unlike BRCA2, which nucleates RAD-51-ssDNA filaments, RFS-1/RIP-1 binds and remodels pre-synaptic filaments to a stabilized, "open," and flexible conformation, in which the ssDNA is more accessible to nuclease digestion and RAD-51 dissociation rate is reduced. Walker box mutations in RFS-1, which abolish filament remodeling, fail to stimulate RAD-51 strand exchange activity, demonstrating that remodeling is essential for RFS-1/RIP-1 function. We propose that Rad51 paralogs stimulate HR by remodeling the Rad51 filament, priming it for strand exchange with the template duplex.
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Affiliation(s)
- Martin R G Taylor
- DNA Damage Response Laboratory, Clare Hall Laboratory, The Francis Crick Institute, South Mimms EN6 3LD, UK
| | - Mário Špírek
- Department of Biology, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, St. Anne's University Hospital in Brno, 62500 Brno, Czech Republic
| | - Kathy R Chaurasiya
- Section of Virology, Single Molecule Imaging Group and MRC Clinical Sciences Centre, Department of Medicine, Imperial College London, London W12 0NN, UK
| | - Jordan D Ward
- DNA Damage Response Laboratory, Clare Hall Laboratory, The Francis Crick Institute, South Mimms EN6 3LD, UK; UCSF-Mission Bay, Genentech Hall S574, San Francisco, CA 94158, USA
| | - Raffaella Carzaniga
- Electron Microscopy Science Technology Platform, Lincoln's Inn Fields Laboratory, The Francis Crick Institute, London WC2A 3LY, UK
| | - Xiong Yu
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Lucy M Collinson
- Electron Microscopy Science Technology Platform, Lincoln's Inn Fields Laboratory, The Francis Crick Institute, London WC2A 3LY, UK
| | - David Rueda
- Section of Virology, Single Molecule Imaging Group and MRC Clinical Sciences Centre, Department of Medicine, Imperial College London, London W12 0NN, UK
| | - Lumir Krejci
- Department of Biology, Masaryk University, 62500 Brno, Czech Republic; International Clinical Research Center, St. Anne's University Hospital in Brno, 62500 Brno, Czech Republic; National Centre for Biomolecular Research, Masaryk University, 62500 Brno, Czech Republic.
| | - Simon J Boulton
- DNA Damage Response Laboratory, Clare Hall Laboratory, The Francis Crick Institute, South Mimms EN6 3LD, UK.
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28
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Prakash R, Zhang Y, Feng W, Jasin M. Homologous recombination and human health: the roles of BRCA1, BRCA2, and associated proteins. Cold Spring Harb Perspect Biol 2015; 7:a016600. [PMID: 25833843 DOI: 10.1101/cshperspect.a016600] [Citation(s) in RCA: 572] [Impact Index Per Article: 63.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Homologous recombination (HR) is a major pathway for the repair of DNA double-strand breaks in mammalian cells, the defining step of which is homologous strand exchange directed by the RAD51 protein. The physiological importance of HR is underscored by the observation of genomic instability in HR-deficient cells and, importantly, the association of cancer predisposition and developmental defects with mutations in HR genes. The tumor suppressors BRCA1 and BRCA2, key players at different stages of HR, are frequently mutated in familial breast and ovarian cancers. Other HR proteins, including PALB2 and RAD51 paralogs, have also been identified as tumor suppressors. This review summarizes recent findings on BRCA1, BRCA2, and associated proteins involved in human disease with an emphasis on their molecular roles and interactions.
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Affiliation(s)
- Rohit Prakash
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Yu Zhang
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Weiran Feng
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065 Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York 10065
| | - Maria Jasin
- Developmental Biology Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065 Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, New York 10065
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29
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Parplys AC, Kratz K, Speed MC, Leung SG, Schild D, Wiese C. RAD51AP1-deficiency in vertebrate cells impairs DNA replication. DNA Repair (Amst) 2014; 24:87-97. [PMID: 25288561 DOI: 10.1016/j.dnarep.2014.09.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 09/06/2014] [Accepted: 09/16/2014] [Indexed: 01/03/2023]
Abstract
RAD51-associated protein 1 (RAD51AP1) is critical for homologous recombination (HR) by interacting with and stimulating the activities of the RAD51 and DMC1 recombinases. In human somatic cells, knockdown of RAD51AP1 results in increased sensitivity to DNA damaging agents and to impaired HR, but the formation of DNA damage-induced RAD51 foci is unaffected. Here, we generated a genetic model system, based on chicken DT40 cells, to assess the phenotype of fully inactivated RAD51AP1 in vertebrate cells. Targeted inactivation of both RAD51AP1 alleles has no effect on either viability or doubling-time in undamaged cells, but leads to increased levels of cytotoxicity after exposure to cisplatin or to ionizing radiation. Interestingly, ectopic expression of GgRAD51AP1, but not of HsRAD51AP1 is able to fully complement in cell survival assays. Notably, in RAD51AP1-deficient DT40 cells the resolution of DNA damage-induced RAD51 foci is greatly slowed down, while their formation is not impaired. We also identify, for the first time, an important role for RAD51AP1 in counteracting both spontaneous and DNA damage-induced replication stress. In human and in chicken cells, RAD51AP1 is required to maintain wild type speed of replication fork progression, and both RAD51AP1-depleted human cells and RAD51AP1-deficient DT40 cells respond to replication stress by a slow-down of replication fork elongation rates. However, increased firing of replication origins occurs in RAD51AP1-/- DT40 cells, likely to ensure the timely duplication of the entire genome. Taken together, our results may explain why RAD51AP1 commonly is overexpressed in tumor cells and tissues, and we speculate that the disruption of RAD51AP1 function could be a promising approach in targeted tumor therapy.
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Affiliation(s)
- Ann C Parplys
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Katja Kratz
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Michael C Speed
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - Stanley G Leung
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
| | - David Schild
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
| | - Claudia Wiese
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States.
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30
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Khasanova OS, Vagin DA, Khasanov FK. Recombinational repair in Schizosaccharomyces pombe: The role of mediator proteins. Mol Biol 2012. [DOI: 10.1134/s0026893312050068] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Alamri OD, Cundy AB, Di Y, Jha AN, Rotchell JM. Ionizing radiation-induced DNA damage response identified in marine mussels, Mytilus sp. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2012; 168:107-112. [PMID: 22609861 DOI: 10.1016/j.envpol.2012.04.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 04/11/2012] [Accepted: 04/12/2012] [Indexed: 06/01/2023]
Abstract
There is growing concern over the potential detrimental impact of ionizing radiation on natural biota. The mechanistic cause-and-effect impact of ionizing radiation has yet to be characterized in any aquatic species. Adopting an integrated approach, including radiochemical analysis of environmental samples, we evaluate molecular responses to ionizing radiation in the marine mussel, Mytilus edulis. These responses included analyses of RAD51 mRNA expression, a gene involved in the repair of DNA double strand breaks, and induction of DNA strand breaks using the comet assay, in samples collected from a site impacted by low level ionizing radiation discharges. Based on activities of the radionuclides measured in sediment and mussel tissue at the discharge site, external and internal dose rates were low, at ca. 0.61 μGyh(-1) and significantly lower than the generic (all species) "no effect" dose rate of 10 uGyh(-1), yet DNA strand breakage and RAD51 mRNA expression were both altered.
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Affiliation(s)
- Ohoud D Alamri
- School of Life Sciences, University of Sussex, Brighton BN1 9QJ, UK
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Urbin SS, Elvers I, Hinz JM, Helleday T, Thompson LH. Uncoupling of RAD51 focus formation and cell survival after replication fork stalling in RAD51D null CHO cells. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2012; 53:114-124. [PMID: 22302683 DOI: 10.1002/em.21672] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 10/24/2011] [Accepted: 10/25/2011] [Indexed: 05/31/2023]
Abstract
In vertebrate cells, the five RAD51 paralogs (XRCC2/3 and RAD51B/C/D) enhance the efficiency of homologous recombination repair (HRR). Stalling and breakage of DNA replication forks is a common event, especially in the large genomes of higher eukaryotes. When cells are exposed to agents that arrest DNA replication, such as hydroxyurea or aphidicolin, fork breakage can lead to chromosomal aberrations and cell killing. We assessed the contribution of the HRR protein RAD51D in resistance to killing by replication-associated DSBs. In response to hydroxyurea, the isogenic rad51d null CHO mutant fails to show any indication of HRR initiation, as assessed by induction RAD51 foci, as expected. Surprisingly, these cells have normal resistance to killing by replication inhibition from either hydroxyurea or aphidicolin, but show the expected sensitivity to camptothecin, which also generates replication-dependent DSBs. In contrast, we confirm that the V79 xrcc2 mutant does show increased sensitivity to hydroxyurea under some conditions, which was correlated to its attenuated RAD51 focus response. In response to the PARP1 inhibitor KU58684, rad51d cells, like other HRR mutants, show exquisite sensitivity (>1000-fold), which is also associated with defective RAD51 focus formation. Thus, rad51d cells are broadly deficient in RAD51 focus formation in response to various agents, but this defect is not invariably associated with increased sensitivity. Our results indicate that RAD51 paralogs do not contribute equally to cellular resistance of inhibitors of DNAreplication, and that the RAD51 foci associated with replication inhibition may not be a reliable indicator of cellular resistance to such agents.
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Affiliation(s)
- Salustra S Urbin
- Biosciences and Biotechnology Division, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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Lin FY, Chan KW, Wang CY, Wong ML, Hsu WL. Purification and functional motifs of the recombinant ATPase of orf virus. Protein Expr Purif 2011; 79:210-6. [PMID: 21540113 DOI: 10.1016/j.pep.2011.04.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 04/11/2011] [Accepted: 04/14/2011] [Indexed: 11/25/2022]
Abstract
Our previous study showed that the recombinant ATPase encoded by the A32L gene of orf virus displayed ATP hydrolysis activity as predicted from its amino acids sequence. This viral ATPase contains four known functional motifs (motifs I-IV) and a novel AYDG motif; they are essential for ATP hydrolysis reaction by binding ATP and magnesium ions. The motifs I and II correspond with the Walker A and B motifs of the typical ATPase, respectively. To examine the biochemical roles of these five conserved motifs, recombinant ATPases of five deletion mutants derived from the Taiping strain were expressed and purified. Their ATPase functions were assayed and compared with those of two wild type strains, Taiping and Nantou isolated in Taiwan. Our results showed that deletions at motifs I-III or IV exhibited lower activity than that of the wild type. Interestingly, deletion of AYDG motif decreased the ATPase activity more significantly than those of motifs I-IV deletions. Divalent ions such as magnesium and calcium were essential for ATPase activity. Moreover, our recombinant proteins of orf virus also demonstrated GTPase activity, though weaker than the original ATPase activity.
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Affiliation(s)
- Fong-Yuan Lin
- Department of Veterinary Medicine, National Chung Hsing University, Taichung 402, Taiwan
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The importance of XRCC2 in RAD51-related DNA damage repair. DNA Repair (Amst) 2010; 9:517-25. [DOI: 10.1016/j.dnarep.2010.01.016] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/04/2009] [Accepted: 01/28/2010] [Indexed: 12/11/2022]
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Crozat E, Meglio A, Allemand JF, Chivers CE, Howarth M, Vénien-Bryan C, Grainge I, Sherratt DJ. Separating speed and ability to displace roadblocks during DNA translocation by FtsK. EMBO J 2010; 29:1423-33. [PMID: 20379135 PMCID: PMC2868570 DOI: 10.1038/emboj.2010.29] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Accepted: 02/12/2010] [Indexed: 11/18/2022] Open
Abstract
FtsK translocates dsDNA directionally at >5 kb/s, even under strong forces. In vivo, the action of FtsK at the bacterial division septum is required to complete the final stages of chromosome unlinking and segregation. Despite the availability of translocase structures, the mechanism by which ATP hydrolysis is coupled to DNA translocation is not understood. Here, we use covalently linked translocase subunits to gain insight into the DNA translocation mechanism. Covalent trimers of wild-type subunits dimerized efficiently to form hexamers with high translocation activity and an ability to activate XerCD-dif chromosome unlinking. Covalent trimers with a catalytic mutation in the central subunit formed hexamers with two mutated subunits that had robust ATPase activity. They showed wild-type translocation velocity in single-molecule experiments, activated translocation-dependent chromosome unlinking, but had an impaired ability to displace either a triplex oligonucleotide, or streptavidin linked to biotin-DNA, during translocation along DNA. This separation of translocation velocity and ability to displace roadblocks is more consistent with a sequential escort mechanism than stochastic, hand-off, or concerted mechanisms.
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Affiliation(s)
- Estelle Crozat
- Department of Biochemistry, University of Oxford, Oxford, UK
| | - Adrien Meglio
- Laboratoire de Physique Statistique et Département de Biologie, Ecole Normale Supérieure, UPMC, Paris 06, Université Paris Diderot, CNRS, Paris, France
| | - Jean-François Allemand
- Laboratoire de Physique Statistique et Département de Biologie, Ecole Normale Supérieure, UPMC, Paris 06, Université Paris Diderot, CNRS, Paris, France
| | | | - Mark Howarth
- Department of Biochemistry, University of Oxford, Oxford, UK
| | | | - Ian Grainge
- Department of Biochemistry, University of Oxford, Oxford, UK
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Zafar F, Seidler SB, Kronenberg A, Schild D, Wiese C. Homologous recombination contributes to the repair of DNA double-strand breaks induced by high-energy iron ions. Radiat Res 2010; 173:27-39. [PMID: 20041757 DOI: 10.1667/rr1910.1] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
To test the contribution of homologous recombinational repair (HRR) in repairing DNA damage sites induced by high-energy iron ions, we used (1) HRR-deficient rodent cells carrying a deletion in the RAD51D gene and (2) syngeneic human cells impaired for HRR by RAD51D or RAD51 knockdown using RNA interference. We found that in response to exposure to iron ions, HRR contributed to cell survival in rodent cells and that HRR deficiency abrogated RAD51 focus formation. Complementation of the HRR defect by human RAD51D rescues both enhanced cytotoxicity and RAD51 focus formation. For human cells irradiated with iron ions, cell survival was decreased, and in p53 mutant cells, the levels of mutagenesis were increased when HRR was impaired. Human cells synchronized in S phase exhibited a more pronounced resistance to iron ions compared with cells in G(1) phase, and this increase in radioresistance was diminished by RAD51 knockdown. These results indicate a role for RAD51-mediated DNA repair (i.e. HRR) in removing a fraction of clustered lesions induced by charged-particle radiation. Our results are the first to directly show the requirement for an intact HRR pathway in human cells in ensuring DNA repair and cell survival after exposure to high-energy high-LET radiation.
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Affiliation(s)
- Faria Zafar
- Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, California 94720, USA
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Rajesh C, Gruver AM, Basrur V, Pittman DL. The interaction profile of homologous recombination repair proteins RAD51C, RAD51D and XRCC2 as determined by proteomic analysis. Proteomics 2009; 9:4071-86. [PMID: 19658102 DOI: 10.1002/pmic.200800977] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The RAD51 family of proteins is involved in homologous recombination (HR) DNA repair and maintaining chromosome integrity. To identify candidates that interact with HR proteins, the mouse RAD51C, RAD51D and XRCC2 proteins were purified using bacterial expression systems and each of them used to co-precipitate interacting partners from mouse embryonic fibroblast cellular extracts. Mass spectroscopic analysis was performed on protein bands obtained after 1-D SDS-PAGE of co-precipitation eluates from cell extracts of mitomycin C treated and untreated mouse embryonic fibroblasts. Profiling of the interacting proteins showed a clear bias toward nucleic acid binding and modification proteins. Interactions of four candidate proteins (SFPQ, NONO, MSH2 and mini chromosome maintenance protein 2) were confirmed by Western blot analysis of co-precipitation eluates and were also verified to form ex vivo complexes with RAD51D. Additional interacting proteins were associated with cell division, embryo development, protein and carbohydrate metabolism, cellular trafficking, protein synthesis, modification or folding, and cell structure or motility functions. Results from this study are an important step toward identifying interacting partners of the RAD51 paralogs and understanding the functional diversity of proteins that assist or regulate HR repair mechanisms.
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Affiliation(s)
- Changanamkandath Rajesh
- Department of Pharmaceutical and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, SC 29208, USA
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XRCC2 and XRCC3 regulate the balance between short- and long-tract gene conversions between sister chromatids. Mol Cell Biol 2009; 29:4283-94. [PMID: 19470754 DOI: 10.1128/mcb.01406-08] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Sister chromatid recombination (SCR) is a potentially error-free pathway for the repair of DNA lesions associated with replication and is thought to be important for suppressing genomic instability. The mechanisms regulating the initiation and termination of SCR in mammalian cells are poorly understood. Previous work has implicated all the Rad51 paralogs in the initiation of gene conversion and the Rad51C/XRCC3 complex in its termination. Here, we show that hamster cells deficient in the Rad51 paralog XRCC2, a component of the Rad51B/Rad51C/Rad51D/XRCC2 complex, reveal a bias in favor of long-tract gene conversion (LTGC) during SCR. This defect is corrected by expression of wild-type XRCC2 and also by XRCC2 mutants defective in ATP binding and hydrolysis. In contrast, XRCC3-mediated homologous recombination and suppression of LTGC are dependent on ATP binding and hydrolysis. These results reveal an unexpectedly general role for Rad51 paralogs in the control of the termination of gene conversion between sister chromatids.
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Gruver AM, Yard BD, McInnes C, Rajesh C, Pittman DL. Functional characterization and identification of mouse Rad51d splice variants. BMC Mol Biol 2009; 10:27. [PMID: 19327148 PMCID: PMC2667185 DOI: 10.1186/1471-2199-10-27] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2008] [Accepted: 03/27/2009] [Indexed: 11/10/2022] Open
Abstract
Background The homologous recombination (HR) pathway is vital for maintaining genomic integrity through the restoration of double-stranded breaks and interstrand crosslinks. The RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, XRCC3) are essential for this process in vertebrates, and the RAD51D paralog is unique in that it participates in both HR repair and telomere maintenance. RAD51D is also known to directly interact with the RAD51C and XRCC2 proteins. Rad51d splice variants have been reported in mouse and human tissues, supportive of a role for alternative splicing in HR regulation. The present study evaluated the interaction of the Rad51d splice isoform products with RAD51C and XRCC2 and their expression patterns. Results Yeast-2-hybrid analysis was used to determine that the Mus musculus Rad51d splice variant product RAD51DΔ7b (deleted for residues 219 through 223) was capable of interacting with both RAD51C and XRCC2 and that RAD51D+int3 interacted with XRCC2. In addition, the linker region (residues 54 through 77) of RAD51D was identified as a region that potentially mediates binding with XRCC2. Cellular localization, detected by EGFP fusion proteins, demonstrated that each of the splice variant products tested was distributed throughout the cell similar to the full-length protein. However, none of the splice variants were capable of restoring resistance of Rad51d-deficient cell lines to mitomycin C. RT-PCR expression analysis revealed that Rad51dΔ3 (deleted for exon 3) and Rad51dΔ5 (deleted for exon 5)transcripts display tissue specific expression patterns with Rad51dΔ3 being detected in each tissue except ovary and Rad51dΔ5 not detected in mammary gland and testis. These expression studies also led to the identification of two additional Rad51d ubiquitously expressed transcripts, one deleted for both exon 9 and 10 and one deleted for only exon 10. Conclusion These results suggest Rad51d alternative splice variants potentially modulate mechanisms of HR by sequestering either RAD51C or XRCC2.
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Affiliation(s)
- Aaron M Gruver
- Department of Pharmaceutical and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina Campus, Columbia, SC 29208, USA.
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Saito T, Gale M. Differential recognition of double-stranded RNA by RIG-I-like receptors in antiviral immunity. ACTA ACUST UNITED AC 2008; 205:1523-7. [PMID: 18591413 PMCID: PMC2442628 DOI: 10.1084/jem.20081210] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Retinoic acid–inducible gene (RIG)-I–like receptors (RLRs) are cytosolic RNA helicases that sense viral RNA and trigger signaling pathways that induce the production of type I interferons (IFNs) and proinflammatory cytokines. RLRs recognize distinct and overlapping sets of viruses, but the mechanisms that dictate this specificity were unknown. A new study now provides evidence for size-based discrimination of double-stranded RNA (dsRNA) by RLRs and suggests how host cells recognize a variety of RNA viruses.
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Affiliation(s)
- Takeshi Saito
- Department of Immunology, University of Washington School of Medicine, Seattle, WA 98195, USA
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Russo J, Balogh GA, Russo IH. Full-term pregnancy induces a specific genomic signature in the human breast. Cancer Epidemiol Biomarkers Prev 2008; 17:51-66. [PMID: 18199711 DOI: 10.1158/1055-9965.epi-07-0678] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Breast cancer risk has traditionally been linked to nulliparity or late first full-term pregnancy, whereas young age at first childbirth, multiparity, and breast-feeding are associated with a reduced risk. Early pregnancy confers protection by inducing breast differentiation, which imprints a specific and permanent genomic signature in experimental rodent models. For testing whether the same phenomenon was detectable in the atrophic breast of postmenopausal parous women, we designed a case-control study for the analysis of the gene expression profile of RNA extracted from epithelial cells microdissected from normal breast tissues obtained from 18 parous and 7 nulliparous women free of breast pathology (controls), and 41 parous and 8 nulliparous women with history of breast cancer (cases). RNA was hybridized to cDNA glass microarrays containing 40,000 genes; arrays were scanned and the images were analyzed using ImaGene software version 4.2. Normalization and statistical analysis were carried out using Linear Models for Microarrays and GeneSight software for hierarchical clustering. The parous control group contained 2,541 gene sequences representing 18 biological processes that were differentially expressed in comparison with the other three groups. Hierarchical clustering of these genes revealed that the combined parity/absence of breast cancer data generated a distinct genomic profile that differed from those of the breast cancer groups, irrespective of parity history, and from the nulliparous cancer-free group, which has been traditionally identified as a high-risk group. The signature that identifies those women in whom parity has been protective will serve as a molecular biomarker of differentiation for evaluating the potential use of preventive agents.
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Affiliation(s)
- Jose Russo
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA.
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Ward JD, Barber LJ, Petalcorin MIR, Yanowitz J, Boulton SJ. Replication blocking lesions present a unique substrate for homologous recombination. EMBO J 2007; 26:3384-96. [PMID: 17611606 PMCID: PMC1933397 DOI: 10.1038/sj.emboj.7601766] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Accepted: 05/24/2007] [Indexed: 02/06/2023] Open
Abstract
Homologous recombination (HR) plays a critical role in the restart of blocked replication forks, but how this is achieved remains poorly understood. We show that mutants in the single Rad51 paralog in Caenorhabditis elegans, rfs-1, permit discrimination between HR substrates generated at DNA double-strand breaks (DSBs), or following replication fork collapse from HR substrates assembled at replication fork barriers (RFBs). Unexpectedly, RFS-1 is dispensable for RAD-51 recruitment to meiotic and ionizing radiation (IR)-induced DSBs and following replication fork collapse, yet, is essential for RAD-51 recruitment to RFBs formed by DNA crosslinking agents and other replication blocking lesions. Deletion of rfs-1 also suppresses the accumulation of toxic HR intermediates in him-6; top-3 mutants and accelerates deletion formation at presumed endogenous RFBs formed by poly G/C tracts in the absence of DOG-1. These data suggest that RFS-1 is not a general mediator of HR-dependent DSB repair, but acts specifically to promote HR at RFBs. HR substrates generated at conventional DSBs or following replication fork collapse are therefore intrinsically different from those produced during normal repair of blocked replication forks.
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Affiliation(s)
- Jordan D Ward
- DNA Damage Response Laboratory, Cancer Research UK, The London Research Institute, Clare Hall Laboratories, South Mimms, Herts, UK
| | - Louise J Barber
- DNA Damage Response Laboratory, Cancer Research UK, The London Research Institute, Clare Hall Laboratories, South Mimms, Herts, UK
| | - Mark IR Petalcorin
- DNA Damage Response Laboratory, Cancer Research UK, The London Research Institute, Clare Hall Laboratories, South Mimms, Herts, UK
| | - Judith Yanowitz
- Carnegie Institution, Department of Embryology, Baltimore, MD, USA
| | - Simon J Boulton
- DNA Damage Response Laboratory, Cancer Research UK, The London Research Institute, Clare Hall Laboratories, South Mimms, Herts, UK
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Grycova L, Lansky Z, Friedlova E, Vlachova V, Kubala M, Obsilova V, Obsil T, Teisinger J. ATP binding site on the C-terminus of the vanilloid receptor. Arch Biochem Biophys 2007; 465:389-98. [PMID: 17706589 DOI: 10.1016/j.abb.2007.06.035] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2007] [Revised: 06/29/2007] [Accepted: 06/30/2007] [Indexed: 10/23/2022]
Abstract
Transient receptor potential channel vanilloid receptor subunit 1 (TRPV1) is a thermosensitive cation channel activated by noxious heat as well as a wide range of chemical stimuli. Although ATP by itself does not directly activate TRPV1, it was shown that intracellular ATP increases its activity by directly interacting with the Walker A motif residing on the C-terminus of TRPV1. In order to identify the amino acid residues that are essential for the binding of ATP to the TRPV1 channel, we performed the following point mutations of the Walker A motif: P732A, D733A, G734A, K735A, D736A, and D737A. Employing bulk fluorescence measurements, namely a TNP-ATP competition assay and FITC labelling and quenching experiments, we identified the key role of the K735 residue in the binding of the nucleotide. Experimental data was interpreted according to our molecular modelling simulations.
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Affiliation(s)
- Lenka Grycova
- Institute of Physiology, Academy of Sciences of the Czech Republic, Vídenská 1083, 14220 Prague, Czech Republic
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