1
|
Kojak N, Kuno J, Fittipaldi KE, Khan A, Wenger D, Glasser M, Donnianni RA, Tang Y, Zhang J, Huling K, Ally R, Mujica AO, Turner T, Magardino G, Huang PY, Kerk SY, Droguett G, Prissette M, Rojas J, Gomez T, Gagliardi A, Hunt C, Rabinowitz JS, Gong G, Poueymirou W, Chiao E, Zambrowicz B, Siao CJ, Kajimura D. Somatic and intergenerational G4C2 hexanucleotide repeat instability in a human C9orf72 knock-in mouse model. Nucleic Acids Res 2024; 52:5732-5755. [PMID: 38597682 PMCID: PMC11162798 DOI: 10.1093/nar/gkae250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 03/19/2024] [Accepted: 03/28/2024] [Indexed: 04/11/2024] Open
Abstract
Expansion of a G4C2 repeat in the C9orf72 gene is associated with familial Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD). To investigate the underlying mechanisms of repeat instability, which occurs both somatically and intergenerationally, we created a novel mouse model of familial ALS/FTD that harbors 96 copies of G4C2 repeats at a humanized C9orf72 locus. In mouse embryonic stem cells, we observed two modes of repeat expansion. First, we noted minor increases in repeat length per expansion event, which was dependent on a mismatch repair pathway protein Msh2. Second, we found major increases in repeat length per event when a DNA double- or single-strand break (DSB/SSB) was artificially introduced proximal to the repeats, and which was dependent on the homology-directed repair (HDR) pathway. In mice, the first mode primarily drove somatic repeat expansion. Major changes in repeat length, including expansion, were observed when SSB was introduced in one-cell embryos, or intergenerationally without DSB/SSB introduction if G4C2 repeats exceeded 400 copies, although spontaneous HDR-mediated expansion has yet to be identified. These findings provide a novel strategy to model repeat expansion in a non-human genome and offer insights into the mechanism behind C9orf72 G4C2 repeat instability.
Collapse
Affiliation(s)
- Nada Kojak
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Junko Kuno
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | - David Wenger
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | - Yajun Tang
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Jade Zhang
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Katie Huling
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Roxanne Ally
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | | | - Pei Yi Huang
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | - Sze Yen Kerk
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | - Jose Rojas
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | | | | | - Guochun Gong
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | - Eric Chiao
- Regeneron Pharmaceuticals, Tarrytown, NY 10591, USA
| | | | | | | |
Collapse
|
2
|
Gadgil RY, Rider SD, Shrestha R, Alhawach V, Hitch D, Leffak M. Microsatellite break-induced replication generates highly mutagenized extrachromosomal circular DNAs. NAR Cancer 2024; 6:zcae027. [PMID: 38854437 PMCID: PMC11161834 DOI: 10.1093/narcan/zcae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 05/17/2024] [Accepted: 05/24/2024] [Indexed: 06/11/2024] Open
Abstract
Extrachromosomal circular DNAs (eccDNAs) are produced from all regions of the eucaryotic genome. We used inverse PCR of non-B microsatellites capable of forming hairpin, triplex, quadruplex and AT-rich structures integrated at a common ectopic chromosomal site to show that these non-B DNAs generate highly mutagenized eccDNAs by replication-dependent mechanisms. Mutagenesis occurs within the non-B DNAs and extends several kilobases bidirectionally into flanking and nonallelic DNA. Each non-B DNA exhibits a different pattern of mutagenesis, while sister clones containing the same non-B DNA also display distinct patterns of recombination, microhomology-mediated template switching and base substitutions. Mutations include mismatches, short duplications, long nontemplated insertions, large deletions and template switches to sister chromatids and nonallelic chromosomes. Drug-induced replication stress or the depletion of DNA repair factors Rad51, the COPS2 signalosome subunit or POLη change the pattern of template switching and alter the eccDNA mutagenic profiles. We propose an asynchronous capture model based on break-induced replication from microsatellite-induced DNA double strand breaks to account for the generation and circularization of mutagenized eccDNAs and the appearance of genomic homologous recombination deficiency (HRD) scars. These results may help to explain the appearance of tumor eccDNAS and their roles in neoantigen production, oncogenesis and resistance to chemotherapy.
Collapse
Affiliation(s)
- Rujuta Yashodhan Gadgil
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - S Dean Rider
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Resha Shrestha
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Venicia Alhawach
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - David C Hitch
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| | - Michael Leffak
- Department of Biochemistry and Molecular Biology, Boonshoft School of Medicine, Wright State University, Dayton, OH 45435, USA
| |
Collapse
|
3
|
Jurkovic CM, Boisvert FM. Evolution of techniques and tools for replication fork proteome and protein interaction studies. Biochem Cell Biol 2024; 102:135-144. [PMID: 38113480 DOI: 10.1139/bcb-2023-0215] [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] [Indexed: 12/21/2023] Open
Abstract
Understanding the complex network of protein-protein interactions (PPI) that govern cellular functions is essential for unraveling the molecular basis of biological processes and diseases. Mass spectrometry (MS) has emerged as a powerful tool for studying protein dynamics, enabling comprehensive analysis of protein function, structure, post-translational modifications, interactions, and localization. This article provides an overview of MS techniques and their applications in proteomics studies, with a focus on the replication fork proteome. The replication fork is a multi-protein assembly involved in DNA replication, and its proper functioning is crucial for maintaining genomic integrity. By combining quantitative MS labeling techniques with various data acquisition methods, researchers have made significant strides in elucidating the complex processes and molecular mechanisms at the replication fork. Overall, MS has revolutionized our understanding of protein dynamics, offering valuable insights into cellular processes and potential targets for therapeutic interventions.
Collapse
Affiliation(s)
- Carla-Marie Jurkovic
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - François-Michel Boisvert
- Department of Immunology and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| |
Collapse
|
4
|
Sogari A, Rovera E, Grasso G, Mariella E, Reilly NM, Lamba S, Mauri G, Durinikova E, Vitiello PP, Lorenzato A, Avolio M, Piumatti E, Bonoldi E, Aquilano MC, Arena S, Sartore-Bianchi A, Siena S, Trusolino L, Donalisio M, Russo M, Di Nicolantonio F, Lembo D, Bardelli A. Tolerance to colibactin correlates with homologous recombination proficiency and resistance to irinotecan in colorectal cancer cells. Cell Rep Med 2024; 5:101376. [PMID: 38228147 PMCID: PMC10897517 DOI: 10.1016/j.xcrm.2023.101376] [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: 04/16/2023] [Revised: 11/08/2023] [Accepted: 12/15/2023] [Indexed: 01/18/2024]
Abstract
The bacterial genotoxin colibactin promotes colorectal cancer (CRC) tumorigenesis, but systematic assessment of its impact on DNA repair is lacking, and its effect on response to DNA-damaging chemotherapeutics is unknown. We find that CRC cell lines display differential response to colibactin on the basis of homologous recombination (HR) proficiency. Sensitivity to colibactin is induced by inhibition of ATM, which regulates DNA double-strand break repair, and blunted by HR reconstitution. Conversely, CRC cells chronically infected with colibactin develop a tolerant phenotype characterized by restored HR activity. Notably, sensitivity to colibactin correlates with response to irinotecan active metabolite SN38, in both cell lines and patient-derived organoids. Moreover, CRC cells that acquire colibactin tolerance develop cross-resistance to SN38, and a trend toward poorer response to irinotecan is observed in a retrospective cohort of CRCs harboring colibactin genomic island. Our results shed insight into colibactin activity and provide translational evidence on its chemoresistance-promoting role in CRC.
Collapse
Affiliation(s)
- Alberto Sogari
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Emanuele Rovera
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Gaia Grasso
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Elisa Mariella
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | | | - Simona Lamba
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Gianluca Mauri
- IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy; Department of Oncology and Hemato-Oncology, Università degli Studi di Milano, Milan, Italy; Department of Hematology, Oncology, and Molecular Medicine, Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | | | - Pietro Paolo Vitiello
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Annalisa Lorenzato
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Marco Avolio
- Candiolo Cancer Institute, FPO-IRCCS, 10060 Candiolo, Italy
| | - Eleonora Piumatti
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Emanuela Bonoldi
- Department of Pathology, Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | | | - Sabrina Arena
- Candiolo Cancer Institute, FPO-IRCCS, 10060 Candiolo, Italy; Department of Oncology, University of Torino, 10060 Candiolo, Italy
| | - Andrea Sartore-Bianchi
- Department of Oncology and Hemato-Oncology, Università degli Studi di Milano, Milan, Italy; Department of Hematology, Oncology, and Molecular Medicine, Grande Ospedale Metropolitano Niguarda, Milan, Italy; Division of Clinical Research and Innovation, Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Salvatore Siena
- Department of Oncology and Hemato-Oncology, Università degli Studi di Milano, Milan, Italy; Department of Hematology, Oncology, and Molecular Medicine, Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Livio Trusolino
- Candiolo Cancer Institute, FPO-IRCCS, 10060 Candiolo, Italy; Department of Oncology, University of Torino, 10060 Candiolo, Italy
| | - Manuela Donalisio
- Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Italy
| | - Mariangela Russo
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy
| | - Federica Di Nicolantonio
- Candiolo Cancer Institute, FPO-IRCCS, 10060 Candiolo, Italy; Department of Oncology, University of Torino, 10060 Candiolo, Italy
| | - David Lembo
- Department of Clinical and Biological Sciences, University of Torino, 10043 Orbassano, Italy
| | - Alberto Bardelli
- Department of Oncology, Molecular Biotechnology Center, University of Torino, Torino, Italy; IFOM ETS - The AIRC Institute of Molecular Oncology, 20139 Milan, Italy.
| |
Collapse
|
5
|
Wu SY, Lai HT, Sanjib Banerjee N, Ma Z, Santana JF, Wei S, Liu X, Zhang M, Zhan J, Chen H, Posner B, Chen Y, Price DH, Chow LT, Zhou J, Chiang CM. IDR-targeting compounds suppress HPV genome replication via disruption of phospho-BRD4 association with DNA damage response factors. Mol Cell 2024; 84:202-220.e15. [PMID: 38103559 PMCID: PMC10843765 DOI: 10.1016/j.molcel.2023.11.022] [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: 03/31/2023] [Revised: 10/14/2023] [Accepted: 11/16/2023] [Indexed: 12/19/2023]
Abstract
Compounds binding to the bromodomains of bromodomain and extra-terminal (BET) family proteins, particularly BRD4, are promising anticancer agents. Nevertheless, side effects and drug resistance pose significant obstacles in BET-based therapeutics development. Using high-throughput screening of a 200,000-compound library, we identified small molecules targeting a phosphorylated intrinsically disordered region (IDR) of BRD4 that inhibit phospho-BRD4 (pBRD4)-dependent human papillomavirus (HPV) genome replication in HPV-containing keratinocytes. Proteomic profiling identified two DNA damage response factors-53BP1 and BARD1-crucial for differentiation-associated HPV genome amplification. pBRD4-mediated recruitment of 53BP1 and BARD1 to the HPV origin of replication occurs in a spatiotemporal and BRD4 long (BRD4-L) and short (BRD4-S) isoform-specific manner. This recruitment is disrupted by phospho-IDR-targeting compounds with little perturbation of the global transcriptome and BRD4 chromatin landscape. The discovery of these protein-protein interaction inhibitors (PPIi) not only demonstrates the feasibility of developing PPIi against phospho-IDRs but also uncovers antiviral agents targeting an epigenetic regulator essential for virus-host interaction and cancer development.
Collapse
Affiliation(s)
- Shwu-Yuan Wu
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hsien-Tsung Lai
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - N Sanjib Banerjee
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Zonghui Ma
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch (UTMB), Galveston, TX 77555, USA
| | - Juan F Santana
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Shuguang Wei
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Xisheng Liu
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Meirong Zhang
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Jian Zhan
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, Nanjing 210009, P.R. China
| | - Haiying Chen
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch (UTMB), Galveston, TX 77555, USA
| | - Bruce Posner
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yadong Chen
- State Key Laboratory of Natural Medicines, Department of Organic Chemistry, China Pharmaceutical University, Nanjing 210009, P.R. China
| | - David H Price
- Department of Biochemistry and Molecular Biology, The University of Iowa, Iowa City, IA 52242, USA
| | - Louise T Chow
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch (UTMB), Galveston, TX 77555, USA.
| | - Cheng-Ming Chiang
- Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
6
|
Gadgil RY, Rider SD, Shrestha R, Alhawach V, Hitch DC, Leffak M. Microsatellite break-induced replication generates highly mutagenized extrachromosomal circular DNAs. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.12.575055. [PMID: 38260482 PMCID: PMC10802558 DOI: 10.1101/2024.01.12.575055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Extrachromosomal circular DNAs (eccDNAs) are produced from all regions of the eucaryotic genome. In tumors, highly transcribed eccDNAs have been implicated in oncogenesis, neoantigen production and resistance to chemotherapy. Here we show that unstable microsatellites capable of forming hairpin, triplex, quadruplex and AT-rich structures generate eccDNAs when integrated at a common ectopic site in human cells. These non-B DNA prone microsatellites form eccDNAs by replication-dependent mechanisms. The microsatellite-based eccDNAs are highly mutagenized and display template switches to sister chromatids and to nonallelic chromosomal sites. High frequency mutagenesis occurs within the eccDNA microsatellites and extends bidirectionally for several kilobases into flanking DNA and nonallelic DNA. Mutations include mismatches, short duplications, longer nontemplated insertions and large deletions. Template switching leads to recurrent deletions and recombination domains within the eccDNAs. Template switching events are microhomology-mediated, but do not occur at all potential sites of complementarity. Each microsatellite exhibits a distinct pattern of recombination, microhomology choice and base substitution signature. Depletion of Rad51, the COPS2 signalosome subunit or POLη alter the eccDNA mutagenic profiles. We propose an asynchronous capture model based on break-induced replication from microsatellite-induced DNA breaks for the generation and circularization of mutagenized eccDNAs and genomic homologous recombination deficiency (HRD) scars.
Collapse
|
7
|
Mackay HL, Stone HR, Ellis K, Ronson GE, Walker AK, Starowicz K, Garvin AJ, van Eijk P, Vaitsiankova A, Vijayendran S, Beesley JF, Petermann E, Brown EJ, Densham RM, Reed SH, Dobbs F, Saponaro M, Morris JR. USP50 suppresses alternative RecQ helicase use and deleterious DNA2 activity during replication. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.574674. [PMID: 38260523 PMCID: PMC10802463 DOI: 10.1101/2024.01.10.574674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Mammalian DNA replication employs several RecQ DNA helicases to orchestrate the faithful duplication of genetic information. Helicase function is often coupled to the activity of specific nucleases, but how helicase and nuclease activities are co-directed is unclear. Here we identify the inactive ubiquitin-specific protease, USP50, as a ubiquitin-binding and chromatin-associated protein required for ongoing replication, fork restart, telomere maintenance and cellular survival during replicative stress. USP50 supports WRN:FEN1 at stalled replication forks, suppresses MUS81-dependent fork collapse and restricts double-strand DNA breaks at GC-rich sequences. Surprisingly we find that cells depleted for USP50 and recovering from a replication block exhibit increased DNA2 and RECQL4 foci and that the defects in ongoing replication, poor fork restart and increased fork collapse seen in these cells are mediated by DNA2, RECQL4 and RECQL5. These data define a novel ubiquitin-dependent pathway that promotes the balance of helicase: nuclease use at ongoing and stalled replication forks.
Collapse
|
8
|
Caldecott KW. Causes and consequences of DNA single-strand breaks. Trends Biochem Sci 2024; 49:68-78. [PMID: 38040599 DOI: 10.1016/j.tibs.2023.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/20/2023] [Accepted: 11/03/2023] [Indexed: 12/03/2023]
Abstract
DNA single-strand breaks (SSBs) are among the most common lesions arising in human cells, with tens to hundreds of thousands arising in each cell, each day. Cells have efficient mechanisms for the sensing and repair of these ubiquitous DNA lesions, but the failure of these processes to rapidly remove SSBs can lead to a variety of pathogenic outcomes. The threat posed by unrepaired SSBs is illustrated by the existence of at least six genetic diseases in which SSB repair (SSBR) is defective, all of which are characterised by neurodevelopmental and/or neurodegenerative pathology. Here, I review current understanding of how SSBs arise and impact on critical molecular processes, such as DNA replication and gene transcription, and their links to human disease.
Collapse
Affiliation(s)
- Keith W Caldecott
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, UK.
| |
Collapse
|
9
|
Nickoloff JA, Jaiswal AS, Sharma N, Williamson EA, Tran MT, Arris D, Yang M, Hromas R. Cellular Responses to Widespread DNA Replication Stress. Int J Mol Sci 2023; 24:16903. [PMID: 38069223 PMCID: PMC10707325 DOI: 10.3390/ijms242316903] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/18/2023] Open
Abstract
Replicative DNA polymerases are blocked by nearly all types of DNA damage. The resulting DNA replication stress threatens genome stability. DNA replication stress is also caused by depletion of nucleotide pools, DNA polymerase inhibitors, and DNA sequences or structures that are difficult to replicate. Replication stress triggers complex cellular responses that include cell cycle arrest, replication fork collapse to one-ended DNA double-strand breaks, induction of DNA repair, and programmed cell death after excessive damage. Replication stress caused by specific structures (e.g., G-rich sequences that form G-quadruplexes) is localized but occurs during the S phase of every cell division. This review focuses on cellular responses to widespread stress such as that caused by random DNA damage, DNA polymerase inhibition/nucleotide pool depletion, and R-loops. Another form of global replication stress is seen in cancer cells and is termed oncogenic stress, reflecting dysregulated replication origin firing and/or replication fork progression. Replication stress responses are often dysregulated in cancer cells, and this too contributes to ongoing genome instability that can drive cancer progression. Nucleases play critical roles in replication stress responses, including MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, FEN1, and TATDN2. Several of these nucleases cleave branched DNA structures at stressed replication forks to promote repair and restart of these forks. We recently defined roles for EEPD1 in restarting stressed replication forks after oxidative DNA damage, and for TATDN2 in mitigating replication stress caused by R-loop accumulation in BRCA1-defective cells. We also discuss how insights into biological responses to genome-wide replication stress can inform novel cancer treatment strategies that exploit synthetic lethal relationships among replication stress response factors.
Collapse
Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Aruna S. Jaiswal
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Elizabeth A. Williamson
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Manh T. Tran
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Dominic Arris
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Ming Yang
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| | - Robert Hromas
- Department of Medicine and the Mays Cancer Center, The University of Texas Health Science Center San Antonio, San Antonio, TX 78229, USA; (A.S.J.); (M.T.T.); (R.H.)
| |
Collapse
|
10
|
Palovcak A, Yuan F, Verdun R, Luo L, Zhang Y. Fanconi anemia associated protein 20 (FAAP20) plays an essential role in homology-directed repair of DNA double-strand breaks. Commun Biol 2023; 6:873. [PMID: 37620397 PMCID: PMC10449828 DOI: 10.1038/s42003-023-05252-9] [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: 12/19/2022] [Accepted: 08/17/2023] [Indexed: 08/26/2023] Open
Abstract
FAAP20 is a Fanconi anemia (FA) protein that associates with the FA core complex to promote FANCD2/FANCI monoubiquitination and activate the damage response to interstrand crosslink damage. Here, we report that FAAP20 has a marked role in homologous recombination at a DNA double-strand break not associated with an ICL and separable from its binding partner FANCA. While FAAP20's role in homologous recombination is not dependent on FANCA, we found that FAAP20 stimulates FANCA's biochemical activity in vitro and participates in the single-strand annealing pathway of double-strand break repair in a FANCA-dependent manner. This indicates that FAAP20 has roles in several homology-directed repair pathways. Like other homology-directed repair factors, FAAP20 loss causes a reduction in nuclear RAD51 Irradiation-induced foci; and sensitizes cancer cells to ionizing radiation and PARP inhibition. In summary, FAAP20 participates in DNA double strand break repair by supporting homologous recombination in a non-redundant manner to FANCA, and single-strand annealing repair via FANCA-mediated strand annealing activity.
Collapse
Affiliation(s)
- Anna Palovcak
- Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Fenghua Yuan
- Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Ramiro Verdun
- Department of Medicine, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Liang Luo
- Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, 33136, USA
| | - Yanbin Zhang
- Department of Biochemistry & Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
- Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, 33136, USA.
| |
Collapse
|
11
|
Parisis N, Dans PD, Jbara M, Singh B, Schausi-Tiffoche D, Molina-Serrano D, Brun-Heath I, Hendrychová D, Maity SK, Buitrago D, Lema R, Nait Achour T, Giunta S, Girardot M, Talarek N, Rofidal V, Danezi K, Coudreuse D, Prioleau MN, Feil R, Orozco M, Brik A, Wu PYJ, Krasinska L, Fisher D. Histone H3 serine-57 is a CHK1 substrate whose phosphorylation affects DNA repair. Nat Commun 2023; 14:5104. [PMID: 37607906 PMCID: PMC10444856 DOI: 10.1038/s41467-023-40843-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 08/12/2023] [Indexed: 08/24/2023] Open
Abstract
Histone post-translational modifications promote a chromatin environment that controls transcription, DNA replication and repair, but surprisingly few phosphorylations have been documented. We report the discovery of histone H3 serine-57 phosphorylation (H3S57ph) and show that it is implicated in different DNA repair pathways from fungi to vertebrates. We identified CHK1 as a major human H3S57 kinase, and disrupting or constitutively mimicking H3S57ph had opposing effects on rate of recovery from replication stress, 53BP1 chromatin binding, and dependency on RAD52. In fission yeast, mutation of all H3 alleles to S57A abrogated DNA repair by both non-homologous end-joining and homologous recombination, while cells with phospho-mimicking S57D alleles were partly compromised for both repair pathways, presented aberrant Rad52 foci and were strongly sensitised to replication stress. Mechanistically, H3S57ph loosens DNA-histone contacts, increasing nucleosome mobility, and interacts with H3K56. Our results suggest that dynamic phosphorylation of H3S57 is required for DNA repair and recovery from replication stress, opening avenues for investigating the role of this modification in other DNA-related processes.
Collapse
Affiliation(s)
- Nikolaos Parisis
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
- Equipe labellisée Ligue contre le Cancer, Paris, France
- BPMP, CNRS, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
- Institut Jacques Monod, CNRS, University Paris Diderot, Paris, France
| | - Pablo D Dans
- IRB Barcelona, BIST, Barcelona, Spain
- Bioinformatics Unit, Institute Pasteur of Montevideo, Montevideo, Uruguay
- Department of Biological Sciences, CENUR North Riverside, University of the Republic (UdelaR), Salto, Uruguay
| | - Muhammad Jbara
- Schulich Faculty of Chemistry, Technion Israel Institute of Technology, Haifa, Israel
- School of Chemistry, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
| | | | | | | | | | - Denisa Hendrychová
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
- Equipe labellisée Ligue contre le Cancer, Paris, France
- Department of Experimental Biology, Faculty of Science, Palacký University Olomouc, Olomouc, Czech Republic
| | - Suman Kumar Maity
- Schulich Faculty of Chemistry, Technion Israel Institute of Technology, Haifa, Israel
| | | | | | - Thiziri Nait Achour
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
- Equipe labellisée Ligue contre le Cancer, Paris, France
| | - Simona Giunta
- The Rockefeller University, New York, NY, USA
- Laboratory of Genome Evolution, Department of Biology and Biotechnology "Charles Darwin", University of Rome Sapienza, Rome, Italy
| | - Michael Girardot
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Nicolas Talarek
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
| | - Valérie Rofidal
- BPMP, CNRS, INRA, Montpellier SupAgro, University of Montpellier, Montpellier, France
| | - Katerina Danezi
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
- Equipe labellisée Ligue contre le Cancer, Paris, France
| | - Damien Coudreuse
- IGDR, CNRS, University of Rennes, Rennes, France
- IBGC, CNRS, University of Bordeaux, Bordeaux, France
| | | | - Robert Feil
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France
| | | | - Ashraf Brik
- Schulich Faculty of Chemistry, Technion Israel Institute of Technology, Haifa, Israel
| | - Pei-Yun Jenny Wu
- IGDR, CNRS, University of Rennes, Rennes, France
- IBGC, CNRS, University of Bordeaux, Bordeaux, France
| | - Liliana Krasinska
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France.
- Equipe labellisée Ligue contre le Cancer, Paris, France.
| | - Daniel Fisher
- IGMM, CNRS, INSERM, University of Montpellier, Montpellier, France.
- Equipe labellisée Ligue contre le Cancer, Paris, France.
| |
Collapse
|
12
|
Petroni M, La Monica V, Fabretti F, Augusto M, Battaglini D, Polonara F, Di Giulio S, Giannini G. The Multiple Faces of the MRN Complex: Roles in Medulloblastoma and Beyond. Cancers (Basel) 2023; 15:3599. [PMID: 37509263 PMCID: PMC10377613 DOI: 10.3390/cancers15143599] [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: 06/06/2023] [Revised: 07/09/2023] [Accepted: 07/10/2023] [Indexed: 07/30/2023] Open
Abstract
Hypomorphic mutations in MRN complex genes are frequently found in cancer, supporting their role as oncosuppressors. However, unlike canonical oncosuppressors, MRN proteins are often overexpressed in tumor tissues, where they actively work to counteract DSBs induced by both oncogene-dependent RS and radio-chemotherapy. Moreover, at the same time, MRN genes are also essential genes, since the constitutive KO of each component leads to embryonic lethality. Therefore, even though it is paradoxical, MRN genes may work as oncosuppressive, oncopromoting, and essential genes. In this review, we discussed how alterations in the MRN complex impact the physiopathology of cancer, in light of our recent discoveries on the gene-dosage-dependent effect of NBS1 in Medulloblastoma. These updates aim to understand whether MRN complex can be realistically used as a prognostic/predictive marker and/or as a therapeutic target for the treatment of cancer patients in the future.
Collapse
Affiliation(s)
- Marialaura Petroni
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
| | - Veronica La Monica
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Francesca Fabretti
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Mariaconcetta Augusto
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Center for Life Nano- & Neuro-Science, Istituto Italiano di Tecnologia (IIT), 00161 Rome, Italy
| | - Damiana Battaglini
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Francesca Polonara
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
| | - Stefano Di Giulio
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
| | - Giuseppe Giannini
- Department of Molecular Medicine, University La Sapienza, 00161 Rome, Italy
- Istituto Pasteur-Fondazione Cenci Bolognetti, 00161 Rome, Italy
| |
Collapse
|
13
|
Holland CL, Weis MF, England CJ, Berry AM, Hall PD, Lewis LK. Deficiency in homologous recombination is associated with changes in cell cycling and morphology in Saccharomyces cerevisiae. Exp Cell Res 2023:113701. [PMID: 37393982 DOI: 10.1016/j.yexcr.2023.113701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 06/23/2023] [Accepted: 06/25/2023] [Indexed: 07/04/2023]
Abstract
Exposure of eukaryotic cells to ionizing radiation or clastogenic chemicals leads to formation of DNA double-strand breaks (DSBs). These lesions are also generated internally by chemicals and enzymes, in the absence of exogenous agents, though the sources and consequences of such endogenously generated DSBs remain poorly understood. In the current study, we have investigated the impact of reduced recombinational repair of endogenous DSBs on stress responses, cell morphology and other physical properties of S. cerevisiae (budding yeast) cells. Use of phase contrast and DAPI-based fluorescence microscopy combined with FACS analysis confirmed that recombination-deficient rad52 cell cultures exhibit chronically high levels of G2 phase cells. Cell cycle phase transit times during G1, S and M were similar in WT and rad52 cells, but the length of G2 phase was increased by three-fold in the mutants. rad52 cells were larger than WT in all phases of the cycle and displayed other quantifiable changes in physical characteristics. The high G2 cell phenotype was abolished when DNA damage checkpoint genes, but not spindle assembly checkpoint genes, were co-inactivated with RAD52. Several other RAD52 group mutants (rad51, rad54, rad55, rad57 and rad59) also exhibited the high G2 cell phenotype. The results indicate that recombination deficiency leads to accumulation of unrepaired DSBs during normal mitotic growth that activate a major stress response and produce distinct changes in cellular physiology and morphology.
Collapse
Affiliation(s)
- Cory L Holland
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - Monica F Weis
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - Corbin J England
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - Armand M Berry
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - Paige D Hall
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA
| | - L Kevin Lewis
- Chemistry and Biochemistry, Texas State University, 601 University Drive, San Marcos, TX, 78666, USA.
| |
Collapse
|
14
|
Pai CC, Durley SC, Cheng WC, Chiang NY, Peters J, Kasparek T, Blaikley E, Wee BY, Walker C, Kearsey SE, Buffa F, Murray JM, Humphrey TC. Homologous recombination suppresses transgenerational DNA end resection and chromosomal instability in fission yeast. Nucleic Acids Res 2023; 51:3205-3222. [PMID: 36951111 PMCID: PMC10123110 DOI: 10.1093/nar/gkad160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Revised: 02/13/2023] [Accepted: 02/23/2023] [Indexed: 03/24/2023] Open
Abstract
Chromosomal instability (CIN) drives cell-to-cell heterogeneity, and the development of genetic diseases, including cancer. Impaired homologous recombination (HR) has been implicated as a major driver of CIN, however, the underlying mechanism remains unclear. Using a fission yeast model system, we establish a common role for HR genes in suppressing DNA double-strand break (DSB)-induced CIN. Further, we show that an unrepaired single-ended DSB arising from failed HR repair or telomere loss is a potent driver of widespread CIN. Inherited chromosomes carrying a single-ended DSB are subject to cycles of DNA replication and extensive end-processing across successive cell divisions. These cycles are enabled by Cullin 3-mediated Chk1 loss and checkpoint adaptation. Subsequent propagation of unstable chromosomes carrying a single-ended DSB continues until transgenerational end-resection leads to fold-back inversion of single-stranded centromeric repeats and to stable chromosomal rearrangements, typically isochromosomes, or to chromosomal loss. These findings reveal a mechanism by which HR genes suppress CIN and how DNA breaks that persist through mitotic divisions propagate cell-to-cell heterogeneity in the resultant progeny.
Collapse
Affiliation(s)
- Chen-Chun Pai
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Samuel C Durley
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Wei-Chen Cheng
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Nien-Yi Chiang
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Jennifer Peters
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Torben Kasparek
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Elizabeth Blaikley
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Boon-Yu Wee
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Carol Walker
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Stephen E Kearsey
- Department of Biology, University of Oxford, Zoology Research and Administration Building, Mansfield Road, Oxford OX1 3SZ, UK
| | - Francesca Buffa
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| | - Johanne M Murray
- Genome Damage and Stability Centre, School of Life Sciences, University of Sussex, Falmer, Brighton, SussexBN1 9RQ, UK
| | - Timothy C Humphrey
- MRC Oxford Institute for Radiation Oncology & Biology, Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK
| |
Collapse
|
15
|
Jaiswal AS, Kim HS, Schärer OD, Sharma N, Williamson E, Srinivasan G, Phillips L, Kong K, Arya S, Misra A, Dutta A, Gupta Y, Walter C, Burma S, Narayan S, Sung P, Nickoloff J, Hromas R. EEPD1 promotes repair of oxidatively-stressed replication forks. NAR Cancer 2023; 5:zcac044. [PMID: 36683914 PMCID: PMC9846428 DOI: 10.1093/narcan/zcac044] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 11/22/2022] [Accepted: 12/14/2022] [Indexed: 01/19/2023] Open
Abstract
Unrepaired oxidatively-stressed replication forks can lead to chromosomal instability and neoplastic transformation or cell death. To meet these challenges cells have evolved a robust mechanism to repair oxidative genomic DNA damage through the base excision repair (BER) pathway, but less is known about repair of oxidative damage at replication forks. We found that depletion or genetic deletion of EEPD1 decreases clonogenic cell survival after oxidative DNA damage. We demonstrate that EEPD1 is recruited to replication forks stressed by oxidative damage induced by H2O2 and that EEPD1 promotes replication fork repair and restart and decreases chromosomal abnormalities after such damage. EEPD1 binds to abasic DNA structures and promotes resolution of genomic abasic sites after oxidative stress. We further observed that restoration of expression of EEPD1 via expression vector transfection restores cell survival and suppresses chromosomal abnormalities induced by oxidative stress in EEPD1-depleted cells. Consistent with this, we found that EEPD1 preserves replication fork integrity by preventing oxidatively-stressed unrepaired fork fusion, thereby decreasing chromosome instability and mitotic abnormalities. Our results indicate a novel role for EEPD1 in replication fork preservation and maintenance of chromosomal stability during oxidative stress.
Collapse
Affiliation(s)
- Aruna S Jaiswal
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Hyun-Suk Kim
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
| | - Orlando D Schärer
- Center for Genomic Integrity, Institute for Basic Science, Ulsan, Republic of Korea
- Department of Biological Sciences, School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Elizabeth A Williamson
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Gayathri Srinivasan
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Linda Phillips
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Kimi Kong
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Shailee Arya
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Anurag Misra
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Arijit Dutta
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Yogesh Gupta
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Christi A Walter
- Department of Cell Systems and Anatomy, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Sandeep Burma
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
- Department of Neurosurgery, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Satya Narayan
- Department of Anatomy and Cell Biology, University of Florida, Gainesville, FL 32610, USA
| | - Patrick Sung
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229, USA
| | - Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| |
Collapse
|
16
|
Stabilization of DNA fork junctions by Smc5/6 complexes revealed by single-molecule imaging. Cell Rep 2022; 41:111778. [PMID: 36476856 PMCID: PMC9756111 DOI: 10.1016/j.celrep.2022.111778] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Revised: 09/15/2022] [Accepted: 11/11/2022] [Indexed: 12/12/2022] Open
Abstract
SMC complexes play key roles in genome maintenance, where they ensure efficient genome replication and segregation. The SMC complex Smc5/6 is a crucial player in DNA replication and repair, yet many molecular features that determine its roles are unclear. Here, we use single-molecule microscopy to investigate Smc5/6's interaction with DNA. We find that Smc5/6 forms oligomers that dynamically redistribute on dsDNA by 1D diffusion and statically bind to ssDNA. Using combined force manipulation and single-molecule microscopy, we generate ssDNA-dsDNA junctions that mimic structures present in DNA repair intermediates or replication forks. We show that Smc5/6 accumulates at these junction sites, stabilizes the fork, and promotes the retention of RPA. Our observations provide a model for the complex's enrichment at sites of replication stress and DNA lesions from where it coordinates the recruitment and activation of downstream repair proteins.
Collapse
|
17
|
Babu S, Takeuchi Y, Masai I. Banp regulates DNA damage response and chromosome segregation during the cell cycle in zebrafish retina. eLife 2022; 11:74611. [PMID: 35942692 PMCID: PMC9363121 DOI: 10.7554/elife.74611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 07/05/2022] [Indexed: 11/25/2022] Open
Abstract
Btg3-associated nuclear protein (Banp) was originally identified as a nuclear matrix-associated region (MAR)-binding protein and it functions as a tumor suppressor. At the molecular level, Banp regulates transcription of metabolic genes via a CGCG-containing motif called the Banp motif. However, its physiological roles in embryonic development are unknown. Here, we report that Banp is indispensable for the DNA damage response and chromosome segregation during mitosis. Zebrafish banp mutants show mitotic cell accumulation and apoptosis in developing retina. We found that DNA replication stress and tp53-dependent DNA damage responses were activated to induce apoptosis in banp mutants, suggesting that Banp is required for regulation of DNA replication and DNA damage repair. Furthermore, consistent with mitotic cell accumulation, chromosome segregation was not smoothly processed from prometaphase to anaphase in banp morphants, leading to a prolonged M-phase. Our RNA- and ATAC-sequencing identified 31 candidates for direct Banp target genes that carry the Banp motif. Interestingly, a DNA replication fork regulator, wrnip1, and two chromosome segregation regulators, cenpt and ncapg, are included in this list. Thus, Banp directly regulates transcription of wrnip1 for recovery from DNA replication stress, and cenpt and ncapg for chromosome segregation during mitosis. Our findings provide the first in vivo evidence that Banp is required for cell-cycle progression and cell survival by regulating DNA damage responses and chromosome segregation during mitosis. In order for a cell to divide, it must progress through a series of carefully controlled steps known as the cell cycle. First, the cell replicates its DNA and both copies get segregated to opposite ends. The cell then splits into two and each new cell receives a copy of the duplicated genetic material. If any of the stages in the cell cycle become disrupted or mis-regulated this can lead to uncontrolled divisions that may result in cancer. Researchers have often used a structure within the eye known as the retina to study the cell cycle in zebrafish and other animals as cells in the retina rapidly divide in a highly controlled manner. A protein called Banp is known to help stop tumors from growing in humans and mice, but its normal role in the body, particularly the cell cycle, has remained unclear. To investigate, Babu et al. studied the retina of mutant zebrafish that were unable to make the Banp protein. The experiments revealed that two stress responses indicating DNA damage or defects in copying DNA were active in the retinal cells of the mutant zebrafish. This suggested that Banp allows cell to progress through the cell cycle by repairing any DNA damage that may arise during replication. Banp does this by activating the gene for another protein called Wrnip1. Babu et al. also found that Banp helps segregate the two copies of DNA during cell division by promoting the activation of two other proteins called Cenpt and Ncapg. Further experiments identified 31 genes that were directly regulated by Banp. These findings demonstrate that Banp is required for zebrafish cells to be able to accurately copy their DNA and divide in to two new cells. In the future, the work of Babu et al. will provide a useful resource to investigate how tumors grow and spread around the body, and may contribute to the development of new treatments for cancer.
Collapse
Affiliation(s)
- Swathy Babu
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Japan
| | - Yuki Takeuchi
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Japan
| | - Ichiro Masai
- Developmental Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Onna, Japan
| |
Collapse
|
18
|
Nickoloff JA. Targeting Replication Stress Response Pathways to Enhance Genotoxic Chemo- and Radiotherapy. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27154736. [PMID: 35897913 PMCID: PMC9330692 DOI: 10.3390/molecules27154736] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 07/20/2022] [Accepted: 07/22/2022] [Indexed: 12/12/2022]
Abstract
Proliferating cells regularly experience replication stress caused by spontaneous DNA damage that results from endogenous reactive oxygen species (ROS), DNA sequences that can assume secondary and tertiary structures, and collisions between opposing transcription and replication machineries. Cancer cells face additional replication stress, including oncogenic stress that results from the dysregulation of fork progression and origin firing, and from DNA damage induced by radiotherapy and most cancer chemotherapeutic agents. Cells respond to such stress by activating a complex network of sensor, signaling and effector pathways that protect genome integrity. These responses include slowing or stopping active replication forks, protecting stalled replication forks from collapse, preventing late origin replication firing, stimulating DNA repair pathways that promote the repair and restart of stalled or collapsed replication forks, and activating dormant origins to rescue adjacent stressed forks. Currently, most cancer patients are treated with genotoxic chemotherapeutics and/or ionizing radiation, and cancer cells can gain resistance to the resulting replication stress by activating pro-survival replication stress pathways. Thus, there has been substantial effort to develop small molecule inhibitors of key replication stress proteins to enhance tumor cell killing by these agents. Replication stress targets include ATR, the master kinase that regulates both normal replication and replication stress responses; the downstream signaling kinase Chk1; nucleases that process stressed replication forks (MUS81, EEPD1, Metnase); the homologous recombination catalyst RAD51; and other factors including ATM, DNA-PKcs, and PARP1. This review provides an overview of replication stress response pathways and discusses recent pre-clinical studies and clinical trials aimed at improving cancer therapy by targeting replication stress response factors.
Collapse
Affiliation(s)
- Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| |
Collapse
|
19
|
Kim SM, Forsburg SL. Determinants of RPA megafoci localization to the nuclear periphery in response to replication stress. G3 (BETHESDA, MD.) 2022; 12:jkac116. [PMID: 35567482 PMCID: PMC9258583 DOI: 10.1093/g3journal/jkac116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/04/2022] [Indexed: 06/15/2023]
Abstract
Upon replication stress, ssDNA, coated by the ssDNA-binding protein RPA, accumulates and generates a signal to activate the replication stress response. Severe replication stress induced by the loss of minichromosome maintenance helicase subunit Mcm4 in the temperature-sensitive Schizosaccharomyces pombe degron mutant (mcm4-dg) results in the formation of a large RPA focus that is translocated to the nuclear periphery. We show that resection and repair processes and chromatin remodeler Swr1/Ino80 are involved in the large RPA foci formation and its relocalization to nuclear periphery. This concentrated accumulation of RPA increases the recruitment of Cds1 to chromatin and results in an aberrant cell cycle that lacks MBF-mediated G1/S accumulation of Tos4. These findings reveal a distinct replication stress response mediated by localized accumulation of RPA that allows the evasion of cell cycle arrest.
Collapse
Affiliation(s)
- Seong Min Kim
- Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90007, USA
| | - Susan L Forsburg
- Corresponding author: Molecular & Computational Biology, University of Southern California, Los Angeles, CA 90007, USA.
| |
Collapse
|
20
|
Nickoloff JA, Sharma N, Taylor L, Allen SJ, Hromas R. Nucleases and Co-Factors in DNA Replication Stress Responses. DNA 2022; 2:68-85. [PMID: 36203968 PMCID: PMC9534323 DOI: 10.3390/dna2010006] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
DNA replication stress is a constant threat that cells must manage to proliferate and maintain genome integrity. DNA replication stress responses, a subset of the broader DNA damage response (DDR), operate when the DNA replication machinery (replisome) is blocked or replication forks collapse during S phase. There are many sources of replication stress, such as DNA lesions caused by endogenous and exogenous agents including commonly used cancer therapeutics, and difficult-to-replicate DNA sequences comprising fragile sites, G-quadraplex DNA, hairpins at trinucleotide repeats, and telomeres. Replication stress is also a consequence of conflicts between opposing transcription and replication, and oncogenic stress which dysregulates replication origin firing and fork progression. Cells initially respond to replication stress by protecting blocked replisomes, but if the offending problem (e.g., DNA damage) is not bypassed or resolved in a timely manner, forks may be cleaved by nucleases, inducing a DNA double-strand break (DSB) and providing a means to accurately restart stalled forks via homologous recombination. However, DSBs pose their own risks to genome stability if left unrepaired or misrepaired. Here we focus on replication stress response systems, comprising DDR signaling, fork protection, and fork processing by nucleases that promote fork repair and restart. Replication stress nucleases include MUS81, EEPD1, Metnase, CtIP, MRE11, EXO1, DNA2-BLM, SLX1-SLX4, XPF-ERCC1-SLX4, Artemis, XPG, and FEN1. Replication stress factors are important in cancer etiology as suppressors of genome instability associated with oncogenic mutations, and as potential cancer therapy targets to enhance the efficacy of chemo- and radiotherapeutics.
Collapse
Affiliation(s)
- Jac A. Nickoloff
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Neelam Sharma
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Lynn Taylor
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Sage J. Allen
- Department of Environmental and Radiological Health Sciences, Colorado State University, Ft. Collins, CO 80523, USA
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX 78229, USA
| |
Collapse
|
21
|
Nickoloff JA, Sharma N, Taylor L, Allen SJ, Lee SH, Hromas R. Metnase and EEPD1: DNA Repair Functions and Potential Targets in Cancer Therapy. Front Oncol 2022; 12:808757. [PMID: 35155245 PMCID: PMC8831698 DOI: 10.3389/fonc.2022.808757] [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: 11/03/2021] [Accepted: 01/12/2022] [Indexed: 12/30/2022] Open
Abstract
Cells respond to DNA damage by activating signaling and DNA repair systems, described as the DNA damage response (DDR). Clarifying DDR pathways and their dysregulation in cancer are important for understanding cancer etiology, how cancer cells exploit the DDR to survive endogenous and treatment-related stress, and to identify DDR targets as therapeutic targets. Cancer is often treated with genotoxic chemicals and/or ionizing radiation. These agents are cytotoxic because they induce DNA double-strand breaks (DSBs) directly, or indirectly by inducing replication stress which causes replication fork collapse to DSBs. EEPD1 and Metnase are structure-specific nucleases, and Metnase is also a protein methyl transferase that methylates histone H3 and itself. EEPD1 and Metnase promote repair of frank, two-ended DSBs, and both promote the timely and accurate restart of replication forks that have collapsed to single-ended DSBs. In addition to its roles in HR, Metnase also promotes DSB repair by classical non-homologous recombination, and chromosome decatenation mediated by TopoIIα. Although mutations in Metnase and EEPD1 are not common in cancer, both proteins are frequently overexpressed, which may help tumor cells manage oncogenic stress or confer resistance to therapeutics. Here we focus on Metnase and EEPD1 DNA repair pathways, and discuss opportunities for targeting these pathways to enhance cancer therapy.
Collapse
Affiliation(s)
- Jac A Nickoloff
- Department of Environmental and Radiological Health Sciences, 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
| | - Lynn Taylor
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Sage J Allen
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, United States
| | - Suk-Hee Lee
- Department of Biochemistry & Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Robert Hromas
- Division of Hematology and Medical Oncology, Department of Medicine and the Mays Cancer Center, University of Texas Health Science Center, San Antonio, TX, United States
| |
Collapse
|
22
|
Rossi MJ, DiDomenico SF, Patel M, Mazin AV. RAD52: Paradigm of Synthetic Lethality and New Developments. Front Genet 2021; 12:780293. [PMID: 34887904 PMCID: PMC8650160 DOI: 10.3389/fgene.2021.780293] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 11/05/2021] [Indexed: 12/31/2022] Open
Abstract
DNA double-strand breaks and inter-strand cross-links are the most harmful types of DNA damage that cause genomic instability that lead to cancer development. The highest fidelity pathway for repairing damaged double-stranded DNA is termed Homologous recombination (HR). Rad52 is one of the key HR proteins in eukaryotes. Although it is critical for most DNA repair and recombination events in yeast, knockouts of mammalian RAD52 lack any discernable phenotypes. As a consequence, mammalian RAD52 has been long overlooked. That is changing now, as recent work has shown RAD52 to be critical for backup DNA repair pathways in HR-deficient cancer cells. Novel findings have shed light on RAD52's biochemical activities. RAD52 promotes DNA pairing (D-loop formation), single-strand DNA and DNA:RNA annealing, and inverse strand exchange. These activities contribute to its multiple roles in DNA damage repair including HR, single-strand annealing, break-induced replication, and RNA-mediated repair of DNA. The contributions of RAD52 that are essential to the viability of HR-deficient cancer cells are currently under investigation. These new findings make RAD52 an attractive target for the development of anti-cancer therapies against BRCA-deficient cancers.
Collapse
|