1
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Rojas P, Wang J, Guglielmi G, Sadurnì MM, Pavlou L, Leung GHD, Rajagopal V, Spill F, Saponaro M. Genome-wide identification of replication fork stalling/pausing sites and the interplay between RNA Pol II transcription and DNA replication progression. Genome Biol 2024; 25:126. [PMID: 38773641 PMCID: PMC11106976 DOI: 10.1186/s13059-024-03278-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 05/14/2024] [Indexed: 05/24/2024] Open
Abstract
BACKGROUND DNA replication progression can be affected by the presence of physical barriers like the RNA polymerases, leading to replication stress and DNA damage. Nonetheless, we do not know how transcription influences overall DNA replication progression. RESULTS To characterize sites where DNA replication forks stall and pause, we establish a genome-wide approach to identify them. This approach uses multiple timepoints during S-phase to identify replication fork/stalling hotspots as replication progresses through the genome. These sites are typically associated with increased DNA damage, overlapped with fragile sites and with breakpoints of rearrangements identified in cancers but do not overlap with replication origins. Overlaying these sites with a genome-wide analysis of RNA polymerase II transcription, we find that replication fork stalling/pausing sites inside genes are directly related to transcription progression and activity. Indeed, we find that slowing down transcription elongation slows down directly replication progression through genes. This indicates that transcription and replication can coexist over the same regions. Importantly, rearrangements found in cancers overlapping transcription-replication collision sites are detected in non-transformed cells and increase following treatment with ATM and ATR inhibitors. At the same time, we find instances where transcription activity favors replication progression because it reduces histone density. CONCLUSIONS Altogether, our findings highlight how transcription and replication overlap during S-phase, with both positive and negative consequences for replication fork progression and genome stability by the coexistence of these two processes.
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Affiliation(s)
- Patricia Rojas
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Jianming Wang
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Giovanni Guglielmi
- School of Mathematics, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Martina Mustè Sadurnì
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Lucas Pavlou
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Geoffrey Ho Duen Leung
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Vijay Rajagopal
- Department of Biomedical Engineering, University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Fabian Spill
- School of Mathematics, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Marco Saponaro
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, B15 2TT, UK.
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2
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Boddu PC, Gupta AK, Roy R, De La Peña Avalos B, Olazabal-Herrero A, Neuenkirchen N, Zimmer JT, Chandhok NS, King D, Nannya Y, Ogawa S, Lin H, Simon MD, Dray E, Kupfer GM, Verma A, Neugebauer KM, Pillai MM. Transcription elongation defects link oncogenic SF3B1 mutations to targetable alterations in chromatin landscape. Mol Cell 2024; 84:1475-1495.e18. [PMID: 38521065 PMCID: PMC11061666 DOI: 10.1016/j.molcel.2024.02.032] [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: 03/28/2023] [Revised: 11/26/2023] [Accepted: 02/27/2024] [Indexed: 03/25/2024]
Abstract
Transcription and splicing of pre-messenger RNA are closely coordinated, but how this functional coupling is disrupted in human diseases remains unexplored. Using isogenic cell lines, patient samples, and a mutant mouse model, we investigated how cancer-associated mutations in SF3B1 alter transcription. We found that these mutations reduce the elongation rate of RNA polymerase II (RNAPII) along gene bodies and its density at promoters. The elongation defect results from disrupted pre-spliceosome assembly due to impaired protein-protein interactions of mutant SF3B1. The decreased promoter-proximal RNAPII density reduces both chromatin accessibility and H3K4me3 marks at promoters. Through an unbiased screen, we identified epigenetic factors in the Sin3/HDAC/H3K4me pathway, which, when modulated, reverse both transcription and chromatin changes. Our findings reveal how splicing factor mutant states behave functionally as epigenetic disorders through impaired transcription-related changes to the chromatin landscape. We also present a rationale for targeting the Sin3/HDAC complex as a therapeutic strategy.
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Affiliation(s)
- Prajwal C Boddu
- Section of Hematology, Yale Cancer Center and Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Suite 786, New Haven, CT 06511, USA
| | - Abhishek K Gupta
- Section of Hematology, Yale Cancer Center and Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Suite 786, New Haven, CT 06511, USA
| | - Rahul Roy
- Section of Hematology, Yale Cancer Center and Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Suite 786, New Haven, CT 06511, USA
| | - Bárbara De La Peña Avalos
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center (UTHSC) at San Antonio, San Antonio, TX, USA
| | - Anne Olazabal-Herrero
- Section of Hematology, Yale Cancer Center and Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Suite 786, New Haven, CT 06511, USA
| | - Nils Neuenkirchen
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA; Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA
| | - Joshua T Zimmer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Namrata S Chandhok
- Division of Hematology, Department of Medicine, Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL, USA
| | - Darren King
- Section of Hematology and Medical Oncology, Department of Internal Medicine and Rogel Cancer Center, University of Michigan Health, Ann Arbor, MI, USA
| | - Yasuhito Nannya
- Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan
| | - Seishi Ogawa
- Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan
| | - Haifan Lin
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA; Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA
| | - Matthew D Simon
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Eloise Dray
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center (UTHSC) at San Antonio, San Antonio, TX, USA
| | - Gary M Kupfer
- Department of Oncology and Pediatrics, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, USA
| | - Amit Verma
- Division of Hemato-Oncology, Department of Medicine and Department of Developmental and Molecular Biology, Albert Einstein-Montefiore Cancer Center, New York, USA
| | - Karla M Neugebauer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA; Yale Center for RNA Science and Medicine, Yale University, New Haven, CT, USA
| | - Manoj M Pillai
- Section of Hematology, Yale Cancer Center and Department of Internal Medicine, Yale University School of Medicine, 300 George Street, Suite 786, New Haven, CT 06511, USA; Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA; Yale Center for RNA Science and Medicine, Yale University, New Haven, CT, USA; Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
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3
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Tian M, Wang Z, Su Z, Shibata E, Shibata Y, Dutta A, Zang C. Integrative analysis of DNA replication origins and ORC-/MCM-binding sites in human cells reveals a lack of overlap. eLife 2024; 12:RP89548. [PMID: 38567819 PMCID: PMC10990492 DOI: 10.7554/elife.89548] [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] [Indexed: 04/05/2024] Open
Abstract
Based on experimentally determined average inter-origin distances of ~100 kb, DNA replication initiates from ~50,000 origins on human chromosomes in each cell cycle. The origins are believed to be specified by binding of factors like the origin recognition complex (ORC) or CTCF or other features like G-quadruplexes. We have performed an integrative analysis of 113 genome-wide human origin profiles (from five different techniques) and five ORC-binding profiles to critically evaluate whether the most reproducible origins are specified by these features. Out of ~7.5 million union origins identified by all datasets, only 0.27% (20,250 shared origins) were reproducibly obtained in at least 20 independent SNS-seq datasets and contained in initiation zones identified by each of three other techniques, suggesting extensive variability in origin usage and identification. Also, 21% of the shared origins overlap with transcriptional promoters, posing a conundrum. Although the shared origins overlap more than union origins with constitutive CTCF-binding sites, G-quadruplex sites, and activating histone marks, these overlaps are comparable or less than that of known transcription start sites, so that these features could be enriched in origins because of the overlap of origins with epigenetically open, promoter-like sequences. Only 6.4% of the 20,250 shared origins were within 1 kb from any of the ~13,000 reproducible ORC-binding sites in human cancer cells, and only 4.5% were within 1 kb of the ~11,000 union MCM2-7-binding sites in contrast to the nearly 100% overlap in the two comparisons in the yeast, Saccharomyces cerevisiae. Thus, in human cancer cell lines, replication origins appear to be specified by highly variable stochastic events dependent on the high epigenetic accessibility around promoters, without extensive overlap between the most reproducible origins and currently known ORC- or MCM-binding sites.
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Affiliation(s)
- Mengxue Tian
- Center for Public Health Genomics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
| | - Zhenjia Wang
- Center for Public Health Genomics, University of Virginia School of MedicineCharlottesvilleUnited States
| | - Zhangli Su
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Genetics, University of Alabama at BirminghamBirminghamUnited States
| | - Etsuko Shibata
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Genetics, University of Alabama at BirminghamBirminghamUnited States
| | - Yoshiyuki Shibata
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Genetics, University of Alabama at BirminghamBirminghamUnited States
| | - Anindya Dutta
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Genetics, University of Alabama at BirminghamBirminghamUnited States
| | - Chongzhi Zang
- Center for Public Health Genomics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Biochemistry and Molecular Genetics, University of Virginia School of MedicineCharlottesvilleUnited States
- Department of Public Health Sciences, University of VirginiaCharlottesvilleUnited States
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4
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Liu Y, Zhangding Z, Liu X, Gan T, Ai C, Wu J, Liang H, Chen M, Guo Y, Lu R, Jiang Y, Ji X, Gao N, Kong D, Li Q, Hu J. Fork coupling directs DNA replication elongation and termination. Science 2024; 383:1215-1222. [PMID: 38484065 DOI: 10.1126/science.adj7606] [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: 07/19/2023] [Accepted: 02/09/2024] [Indexed: 03/19/2024]
Abstract
DNA replication is initiated at multiple loci to ensure timely duplication of eukaryotic genomes. Sister replication forks progress bidirectionally, and replication terminates when two convergent forks encounter one another. To investigate the coordination of replication forks, we developed a replication-associated in situ HiC method to capture chromatin interactions involving nascent DNA. We identify more than 2000 fountain-like structures of chromatin contacts in human and mouse genomes, indicative of coupling of DNA replication forks. Replication fork interaction not only occurs between sister forks but also involves forks from two distinct origins to predetermine replication termination. Termination-associated chromatin fountains are sensitive to replication stress and lead to coupled forks-associated genomic deletions in cancers. These findings reveal the spatial organization of DNA replication forks within the chromatin context.
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Affiliation(s)
- Yang Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Zhengrong Zhangding
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
| | - Xuhao Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
| | - Tingting Gan
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
- Peking University ChengDu Academy for Advanced Interdisciplinary Biotechnologies, Chengdu, Sichuan 610213, China
| | - Chen Ai
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Jinchun Wu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Haoxin Liang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
| | - Mohan Chen
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
| | - Yuefeng Guo
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
| | - Rusen Lu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Yongpeng Jiang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Xiong Ji
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
| | - Ning Gao
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing 100871, China
| | - Daochun Kong
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Qing Li
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing 100871, China
| | - Jiazhi Hu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University; Beijing 100871, China
- PKU-THU Center for Life Sciences, Peking University, Beijing 100871, China
- Peking University ChengDu Academy for Advanced Interdisciplinary Biotechnologies, Chengdu, Sichuan 610213, China
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5
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Tian M, Wang Z, Su Z, Shibata E, Shibata Y, Dutta A, Zang C. Integrative analysis of DNA replication origins and ORC/MCM binding sites in human cells reveals a lack of overlap. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.25.550556. [PMID: 37546918 PMCID: PMC10402023 DOI: 10.1101/2023.07.25.550556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Based on experimentally determined average inter-origin distances of ∼100 kb, DNA replication initiates from ∼50,000 origins on human chromosomes in each cell cycle. The origins are believed to be specified by binding of factors like the Origin Recognition Complex (ORC) or CTCF or other features like G-quadruplexes. We have performed an integrative analysis of 113 genome-wide human origin profiles (from five different techniques) and 5 ORC-binding profiles to critically evaluate whether the most reproducible origins are specified by these features. Out of ∼7.5 million union origins identified by all datasets, only 0.27% were reproducibly obtained in at least 20 independent SNS-seq datasets and contained in initiation zones identified by each of three other techniques (20,250 shared origins), suggesting extensive variability in origin usage and identification. 21% of the shared origins overlap with transcriptional promoters, posing a conundrum. Although the shared origins overlap more than union origins with constitutive CTCF binding sites, G-quadruplex sites and activating histone marks, these overlaps are comparable or less than that of known Transcription Start Sites, so that these features could be enriched in origins because of the overlap of origins with epigenetically open, promoter-like sequences. Only 6.4% of the 20,250 shared origins were within 1 kb from any of the ∼13,000 reproducible ORC binding sites in human cancer cells, and only 4.5% were within 1 kb of the ∼11,000 union MCM2-7 binding sites in contrast to the nearly 100% overlap in the two comparisons in the yeast, S. cerevisiae . Thus, in human cancer cell lines, replication origins appear to be specified by highly variable stochastic events dependent on the high epigenetic accessibility around promoters, without extensive overlap between the most reproducible origins and currently known ORC- or MCM-binding sites.
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6
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Bayona-Feliu A, Herrera-Moyano E, Badra-Fajardo N, Galván-Femenía I, Soler-Oliva ME, Aguilera A. The chromatin network helps prevent cancer-associated mutagenesis at transcription-replication conflicts. Nat Commun 2023; 14:6890. [PMID: 37898641 PMCID: PMC10613258 DOI: 10.1038/s41467-023-42653-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 10/09/2023] [Indexed: 10/30/2023] Open
Abstract
Genome instability is a feature of cancer cells, transcription being an important source of DNA damage. This is in large part associated with R-loops, which hamper replication, especially at head-on transcription-replication conflicts (TRCs). Here we show that TRCs trigger a DNA Damage Response (DDR) involving the chromatin network to prevent genome instability. Depletion of the key chromatin factors INO80, SMARCA5 and MTA2 results in TRCs, fork stalling and R-loop-mediated DNA damage which mostly accumulates at S/G2, while histone H3 Ser10 phosphorylation, a mark of chromatin compaction, is enriched at TRCs. Strikingly, TRC regions show increased mutagenesis in cancer cells with signatures of homologous recombination deficiency, transcription-coupled nucleotide excision repair (TC-NER) and of the AID/APOBEC cytidine deaminases, being predominant at head-on collisions. Thus, our results support that the chromatin network prevents R-loops and TRCs from genomic instability and mutagenic signatures frequently associated with cancer.
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Affiliation(s)
- Aleix Bayona-Feliu
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092, Seville, Spain.
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Seville, Spain.
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
| | - Emilia Herrera-Moyano
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092, Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Seville, Spain
| | - Nibal Badra-Fajardo
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092, Seville, Spain
| | - Iván Galván-Femenía
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - María Eugenia Soler-Oliva
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092, Seville, Spain
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Seville, Spain
| | - Andrés Aguilera
- Centro Andaluz de Biología Molecular y Medicina Regenerativa CABIMER, Universidad de Sevilla-CSIC-Universidad Pablo de Olavide, 41092, Seville, Spain.
- Departamento de Genética, Facultad de Biología, Universidad de Sevilla, 41012, Seville, Spain.
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7
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Wu J, Liu Y, Zhangding Z, Liu X, Ai C, Gan T, Liang H, Guo Y, Chen M, Liu Y, Yin J, Zhang W, Hu J. Cohesin maintains replication timing to suppress DNA damage on cancer genes. Nat Genet 2023; 55:1347-1358. [PMID: 37500731 DOI: 10.1038/s41588-023-01458-z] [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: 09/29/2022] [Accepted: 06/26/2023] [Indexed: 07/29/2023]
Abstract
Cohesin loss-of-function mutations are frequently observed in tumors, but the mechanism underlying its role in tumorigenesis is unclear. Here, we found that depletion of RAD21, a core subunit of cohesin, leads to massive genome-wide DNA breaks and 147 translocation hotspot genes, co-mutated with cohesin in multiple cancers. Increased DNA damages are independent of RAD21-loss-induced transcription alteration and loop anchor disruption. However, damage-induced chromosomal translocations coincide with the asymmetrically distributed Okazaki fragments of DNA replication, suggesting that RAD21 depletion causes replication stresses evidenced by the slower replication speed and increased stalled forks. Mechanistically, approximately 30% of the human genome exhibits an earlier replication timing after RAD21 depletion, caused by the early initiation of >900 extra dormant origins. Correspondingly, most translocation hotspot genes lie in timing-altered regions. Therefore, we conclude that cohesin dysfunction causes replication stresses induced by excessive DNA replication initiation, resulting in gross DNA damages that may promote tumorigenesis.
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Affiliation(s)
- Jinchun Wu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Yang Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Zhengrong Zhangding
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Xuhao Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Chen Ai
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Tingting Gan
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Haoxin Liang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Yuefeng Guo
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Mohan Chen
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Yiyang Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Jianhang Yin
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Weiwei Zhang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China
| | - Jiazhi Hu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Center for Life Sciences, Genome Editing Research Center, Peking University, Beijing, China.
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8
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Liu Y, Wu X, d'Aubenton-Carafa Y, Thermes C, Chen CL. OKseqHMM: a genome-wide replication fork directionality analysis toolkit. Nucleic Acids Res 2023; 51:e22. [PMID: 36629249 PMCID: PMC9976876 DOI: 10.1093/nar/gkac1239] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 12/06/2022] [Accepted: 12/19/2022] [Indexed: 01/12/2023] Open
Abstract
During each cell division, tens of thousands of DNA replication origins are co-ordinately activated to ensure the complete duplication of the human genome. However, replication fork progression can be challenged by many factors, including co-directional and head-on transcription-replication conflicts (TRC). Head-on TRCs are more dangerous for genome integrity. To study the direction of replication fork movement and TRCs, we developed a bioinformatics toolkit called OKseqHMM (https://github.com/CL-CHEN-Lab/OK-Seq, https://doi.org/10.5281/zenodo.7428883). Then, we used OKseqHMM to analyse a large number of datasets obtained by Okazaki fragment sequencing to directly measure the genome-wide replication fork directionality (RFD) and to accurately predict replication initiation and termination at a fine resolution in organisms including yeast, mouse and human. We also successfully applied our analysis to other genome-wide sequencing techniques that also contain RFD information (e.g. eSPAN, TrAEL-seq). Our toolkit can be used to predict replication initiation and fork progression direction genome-wide in a wide range of cell models and growth conditions. Comparing the replication and transcription directions allows identifying loci at risk of TRCs, particularly head-on TRCs, and investigating their role in genome instability by checking DNA damage data, which is of prime importance for human health.
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Affiliation(s)
- Yaqun Liu
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR3244, Dynamics of Genetic Information, 75005 Paris, France
| | - Xia Wu
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR3244, Dynamics of Genetic Information, 75005 Paris, France
| | - Yves d'Aubenton-Carafa
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Claude Thermes
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Chun-Long Chen
- Institut Curie, Université PSL, Sorbonne Université, CNRS UMR3244, Dynamics of Genetic Information, 75005 Paris, France
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9
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Boddu PC, Gupta A, Roy R, De La Pena Avalos B, Herrero AO, Neuenkirchen N, Zimmer J, Chandhok N, King D, Nannya Y, Ogawa S, Lin H, Simon M, Dray E, Kupfer G, Verma AK, Neugebauer KM, Pillai MM. Transcription elongation defects link oncogenic splicing factor mutations to targetable alterations in chromatin landscape. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.25.530019. [PMID: 36891287 PMCID: PMC9994134 DOI: 10.1101/2023.02.25.530019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Transcription and splicing of pre-messenger RNA are closely coordinated, but how this functional coupling is disrupted in human disease remains unexplored. Here, we investigated the impact of non-synonymous mutations in SF3B1 and U2AF1, two commonly mutated splicing factors in cancer, on transcription. We find that the mutations impair RNA Polymerase II (RNAPII) transcription elongation along gene bodies leading to transcription-replication conflicts, replication stress and altered chromatin organization. This elongation defect is linked to disrupted pre-spliceosome assembly due to impaired association of HTATSF1 with mutant SF3B1. Through an unbiased screen, we identified epigenetic factors in the Sin3/HDAC complex, which, when modulated, normalize transcription defects and their downstream effects. Our findings shed light on the mechanisms by which oncogenic mutant spliceosomes impact chromatin organization through their effects on RNAPII transcription elongation and present a rationale for targeting the Sin3/HDAC complex as a potential therapeutic strategy. GRAPHICAL ABSTRACT HIGHLIGHTS Oncogenic mutations of SF3B1 and U2AF1 cause a gene-body RNAPII elongation defectRNAPII transcription elongation defect leads to transcription replication conflicts, DNA damage response, and changes to chromatin organization and H3K4me3 marksThe transcription elongation defect is linked to disruption of the early spliceosome formation through impaired interaction of HTATSF1 with mutant SF3B1.Changes to chromatin organization reveal potential therapeutic strategies by targeting the Sin3/HDAC pathway.
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10
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Genome-wide measurement of DNA replication fork directionality and quantification of DNA replication initiation and termination with Okazaki fragment sequencing. Nat Protoc 2023; 18:1260-1295. [PMID: 36653528 DOI: 10.1038/s41596-022-00793-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 11/09/2022] [Indexed: 01/19/2023]
Abstract
Studying the dynamics of genome replication in mammalian cells has been historically challenging. To reveal the location of replication initiation and termination in the human genome, we developed Okazaki fragment sequencing (OK-seq), a quantitative approach based on the isolation and strand-specific sequencing of Okazaki fragments, the lagging strand replication intermediates. OK-seq quantitates the proportion of leftward- and rightward-oriented forks at every genomic locus and reveals the location and efficiency of replication initiation and termination events. Here we provide the detailed experimental procedures for performing OK-seq in unperturbed cultured human cells and budding yeast and the bioinformatics pipelines for data processing and computation of replication fork directionality. Furthermore, we present the analytical approach based on a hidden Markov model, which allows automated detection of ascending, descending and flat replication fork directionality segments revealing the zones of replication initiation, termination and unidirectional fork movement across the entire genome. These tools are essential for the accurate interpretation of human and yeast replication programs. The experiments and the data processing can be accomplished within six days. Besides revealing the genome replication program in fine detail, OK-seq has been instrumental in numerous studies unravelling mechanisms of genome stability, epigenome maintenance and genome evolution.
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11
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Jodkowska K, Pancaldi V, Rigau M, Almeida R, Fernández-Justel J, Graña-Castro O, Rodríguez-Acebes S, Rubio-Camarillo M, Carrillo-de Santa Pau E, Pisano D, Al-Shahrour F, Valencia A, Gómez M, Méndez J. 3D chromatin connectivity underlies replication origin efficiency in mouse embryonic stem cells. Nucleic Acids Res 2022; 50:12149-12165. [PMID: 36453993 PMCID: PMC9757045 DOI: 10.1093/nar/gkac1111] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 10/31/2022] [Accepted: 11/25/2022] [Indexed: 12/03/2022] Open
Abstract
In mammalian cells, chromosomal replication starts at thousands of origins at which replisomes are assembled. Replicative stress triggers additional initiation events from 'dormant' origins whose genomic distribution and regulation are not well understood. In this study, we have analyzed origin activity in mouse embryonic stem cells in the absence or presence of mild replicative stress induced by aphidicolin, a DNA polymerase inhibitor, or by deregulation of origin licensing factor CDC6. In both cases, we observe that the majority of stress-responsive origins are also active in a small fraction of the cell population in a normal S phase, and stress increases their frequency of activation. In a search for the molecular determinants of origin efficiency, we compared the genetic and epigenetic features of origins displaying different levels of activation, and integrated their genomic positions in three-dimensional chromatin interaction networks derived from high-depth Hi-C and promoter-capture Hi-C data. We report that origin efficiency is directly proportional to the proximity to transcriptional start sites and to the number of contacts established between origin-containing chromatin fragments, supporting the organization of origins in higher-level DNA replication factories.
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Affiliation(s)
| | | | | | | | - José M Fernández-Justel
- Functional Organization of the Mammalian Genome Group, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Madrid, Spain
| | - Osvaldo Graña-Castro
- Bioinformatics Unit, Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain,Institute of Applied Molecular Medicine (IMMA-Nemesio Díez), San Pablo-CEU University, Boadilla del Monte, Madrid, Spain
| | - Sara Rodríguez-Acebes
- DNA Replication Group, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Miriam Rubio-Camarillo
- Bioinformatics Unit, Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | | | - David Pisano
- Bioinformatics Unit, Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Fátima Al-Shahrour
- Bioinformatics Unit, Structural Biology Programme, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Alfonso Valencia
- Computational Biology Life Sciences Group, Barcelona Supercomputing Center (BSC), Barcelona, Spain
| | - María Gómez
- Correspondence may also be addressed to María Gómez. Tel: +34 911964724; Fax: +34 911964420;
| | - Juan Méndez
- To whom correspondence should be addressed. Tel: +34 917328000; Fax: +34 917328033;
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12
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Effects of replication domains on genome-wide UV-induced DNA damage and repair. PLoS Genet 2022; 18:e1010426. [PMID: 36155646 PMCID: PMC9536635 DOI: 10.1371/journal.pgen.1010426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 10/06/2022] [Accepted: 09/12/2022] [Indexed: 11/19/2022] Open
Abstract
Nucleotide excision repair is the primary repair mechanism that removes UV-induced DNA lesions in placentals. Unrepaired UV-induced lesions could result in mutations during DNA replication. Although the mutagenesis of pyrimidine dimers is reasonably well understood, the direct effects of replication fork progression on nucleotide excision repair are yet to be clarified. Here, we applied Damage-seq and XR-seq techniques and generated replication maps in synchronized UV-treated HeLa cells. The results suggest that ongoing replication stimulates local repair in both early and late replication domains. Additionally, it was revealed that lesions on lagging strand templates are repaired slower in late replication domains, which is probably due to the imbalanced sequence context. Asymmetric relative repair is in line with the strand bias of melanoma mutations, suggesting a role of exogenous damage, repair, and replication in mutational strand asymmetry.
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13
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Guilbaud G, Murat P, Wilkes HS, Lerner LK, Sale JE, Krude T. Determination of human DNA replication origin position and efficiency reveals principles of initiation zone organisation. Nucleic Acids Res 2022; 50:7436-7450. [PMID: 35801867 PMCID: PMC9303276 DOI: 10.1093/nar/gkac555] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 06/14/2022] [Accepted: 06/20/2022] [Indexed: 12/16/2022] Open
Abstract
Replication of the human genome initiates within broad zones of ∼150 kb. The extent to which firing of individual DNA replication origins within initiation zones is spatially stochastic or localised at defined sites remains a matter of debate. A thorough characterisation of the dynamic activation of origins within initiation zones is hampered by the lack of a high-resolution map of both their position and efficiency. To address this shortcoming, we describe a modification of initiation site sequencing (ini-seq), based on density substitution. Newly replicated DNA is rendered 'heavy-light' (HL) by incorporation of BrdUTP while unreplicated DNA remains 'light-light' (LL). Replicated HL-DNA is separated from unreplicated LL-DNA by equilibrium density gradient centrifugation, then both fractions are subjected to massive parallel sequencing. This allows precise mapping of 23,905 replication origins simultaneously with an assignment of a replication initiation efficiency score to each. We show that origin firing within early initiation zones is not randomly distributed. Rather, origins are arranged hierarchically with a set of very highly efficient origins marking zone boundaries. We propose that these origins explain much of the early firing activity arising within initiation zones, helping to unify the concept of replication initiation zones with the identification of discrete replication origin sites.
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Affiliation(s)
- Guillaume Guilbaud
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Pierre Murat
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Helen S Wilkes
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK
| | - Leticia Koch Lerner
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Julian E Sale
- Division of Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Torsten Krude
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ, UK
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14
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The SWI/SNF chromatin remodeling complex helps resolve R-loop-mediated transcription-replication conflicts. Nat Genet 2021; 53:1050-1063. [PMID: 33986538 DOI: 10.1038/s41588-021-00867-2] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 04/06/2021] [Indexed: 02/03/2023]
Abstract
ATP-dependent chromatin remodelers are commonly mutated in human cancer. Mammalian SWI/SNF complexes comprise three conserved multisubunit chromatin remodelers (cBAF, ncBAF and PBAF) that share the BRG1 (also known as SMARCA4) subunit responsible for the main ATPase activity. BRG1 is the most frequently mutated Snf2-like ATPase in cancer. In the present study, we have investigated the role of SWI/SNF in genome instability, a hallmark of cancer cells, given its role in transcription, DNA replication and DNA-damage repair. We show that depletion of BRG1 increases R-loops and R-loop-dependent DNA breaks, as well as transcription-replication (T-R) conflicts. BRG1 colocalizes with R-loops and replication fork blocks, as determined by FANCD2 foci, with BRG1 depletion being epistatic to FANCD2 silencing. Our study, extended to other components of SWI/SNF, uncovers a key role of the SWI/SNF complex, in particular cBAF, in helping resolve R-loop-mediated T-R conflicts, thus, unveiling a new mechanism by which chromatin remodeling protects genome integrity.
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15
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Liu Y, Ai C, Gan T, Wu J, Jiang Y, Liu X, Lu R, Gao N, Li Q, Ji X, Hu J. Transcription shapes DNA replication initiation to preserve genome integrity. Genome Biol 2021; 22:176. [PMID: 34108027 PMCID: PMC8188667 DOI: 10.1186/s13059-021-02390-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Early DNA replication occurs within actively transcribed chromatin compartments in mammalian cells, raising the immediate question of how early DNA replication coordinates with transcription to avoid collisions and DNA damage. RESULTS We develop a high-throughput nucleoside analog incorporation sequencing assay and identify thousands of early replication initiation zones in both mouse and human cells. The identified early replication initiation zones fall in open chromatin compartments and are mutually exclusive with transcription elongation. Of note, early replication initiation zones are mainly located in non-transcribed regions adjacent to transcribed regions. Mechanistically, we find that RNA polymerase II actively redistributes the chromatin-bound mini-chromosome maintenance complex (MCM), but not the origin recognition complex (ORC), to actively restrict early DNA replication initiation outside of transcribed regions. In support of this finding, we detect apparent MCM accumulation and DNA replication initiation in transcribed regions due to anchoring of nuclease-dead Cas9 at transcribed genes, which stalls RNA polymerase II. Finally, we find that the orchestration of early DNA replication initiation by transcription efficiently prevents gross DNA damage. CONCLUSION RNA polymerase II redistributes MCM complexes, but not the ORC, to prevent early DNA replication from initiating within transcribed regions. This RNA polymerase II-driven MCM redistribution spatially separates transcription and early DNA replication events and avoids the transcription-replication initiation collision, thereby providing a critical regulatory mechanism to preserve genome stability.
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Affiliation(s)
- Yang Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Chen Ai
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
| | - Tingting Gan
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Jinchun Wu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Yongpeng Jiang
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Xuhao Liu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
| | - Rusen Lu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Ning Gao
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- State Key Laboratory of Membrane Biology, School of Life Sciences, Peking University, Beijing, 100871, China
| | - Qing Li
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, 100871, China
| | - Xiong Ji
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
| | - Jiazhi Hu
- The MOE Key Laboratory of Cell Proliferation and Differentiation, School of Life Sciences, Genome Editing Research Center, Peking University, Beijing, 100871, China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
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16
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Kirstein N, Buschle A, Wu X, Krebs S, Blum H, Kremmer E, Vorberg IM, Hammerschmidt W, Lacroix L, Hyrien O, Audit B, Schepers A. Human ORC/MCM density is low in active genes and correlates with replication time but does not delimit initiation zones. eLife 2021; 10:62161. [PMID: 33683199 PMCID: PMC7993996 DOI: 10.7554/elife.62161] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 03/05/2021] [Indexed: 12/22/2022] Open
Abstract
Eukaryotic DNA replication initiates during S phase from origins that have been licensed in the preceding G1 phase. Here, we compare ChIP-seq profiles of the licensing factors Orc2, Orc3, Mcm3, and Mcm7 with gene expression, replication timing, and fork directionality profiles obtained by RNA-seq, Repli-seq, and OK-seq. Both, the origin recognition complex (ORC) and the minichromosome maintenance complex (MCM) are significantly and homogeneously depleted from transcribed genes, enriched at gene promoters, and more abundant in early- than in late-replicating domains. Surprisingly, after controlling these variables, no difference in ORC/MCM density is detected between initiation zones, termination zones, unidirectionally replicating regions, and randomly replicating regions. Therefore, ORC/MCM density correlates with replication timing but does not solely regulate the probability of replication initiation. Interestingly, H4K20me3, a histone modification proposed to facilitate late origin licensing, was enriched in late-replicating initiation zones and gene deserts of stochastic replication fork direction. We discuss potential mechanisms specifying when and where replication initiates in human cells.
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Affiliation(s)
- Nina Kirstein
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Munich, Germany
| | - Alexander Buschle
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health and German Center for Infection Research (DZIF), Munich, Germany
| | - Xia Wu
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Stefan Krebs
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center of the Ludwig-Maximilians Universität (LMU) München, Munich, Germany
| | - Helmut Blum
- Laboratory for Functional Genome Analysis (LAFUGA), Gene Center of the Ludwig-Maximilians Universität (LMU) München, Munich, Germany
| | - Elisabeth Kremmer
- Institute for Molecular Immunology, Monoclonal Antibody Core Facility, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - Ina M Vorberg
- German Center for Neurodegenerative Diseases (DZNE e.V.), Bonn, Germany.,Rheinische Friedrich-Wilhelms-Universität Bonn, Bonn, Germany
| | - Wolfgang Hammerschmidt
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health and German Center for Infection Research (DZIF), Munich, Germany
| | - Laurent Lacroix
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Olivier Hyrien
- Institut de Biologie de l'ENS (IBENS), Département de Biologie, Ecole Normale Supérieure, CNRS, Inserm, PSL Research University, Paris, France
| | - Benjamin Audit
- Univ Lyon, ENS de Lyon, Univ. Claude Bernard, CNRS, Laboratoire de Physique, 69342 Lyon, France
| | - Aloys Schepers
- Research Unit Gene Vectors, Helmholtz Zentrum München (GmbH), German Research Center for Environmental Health, Munich, Germany
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17
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Monitoring genome-wide replication fork directionality by Okazaki fragment sequencing in mammalian cells. Nat Protoc 2021; 16:1193-1218. [PMID: 33442052 DOI: 10.1038/s41596-020-00454-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 10/25/2020] [Indexed: 11/08/2022]
Abstract
The ability to monitor DNA replication fork directionality at the genome-wide scale is paramount for a greater understanding of how genetic and environmental perturbations can impact replication dynamics in human cells. Here we describe a detailed protocol for isolating and sequencing Okazaki fragments from asynchronously growing mammalian cells, termed Okazaki fragment sequencing (Ok-seq), for the purpose of quantitatively determining replication initiation and termination frequencies around specific genomic loci by meta-analyses. Briefly, cells are pulsed with 5-ethynyl-2'-deoxyuridine (EdU) to label newly synthesized DNA, and collected for DNA extraction. After size fractionation on a sucrose gradient, Okazaki fragments are concentrated and purified before click chemistry is used to tag the EdU label with a biotin conjugate that is cleavable under mild conditions. Biotinylated Okazaki fragments are then captured on streptavidin beads and ligated to Illumina adapters before library preparation for Illumina sequencing. The use of Ok-seq to interrogate genome-wide replication fork initiation and termination efficiencies can be applied to all unperturbed, asynchronously growing mammalian cells or under conditions of replication stress, and the assay can be performed in less than 2 weeks.
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18
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Iqbal Z, Absar M, Mahmood A, Aleem A, Iqbal M, Jameel A, Akhtar T, Karim S, Rasool M, Mirza Z, Khalid M, Akram AM, Sabar MF, Khalid AM, Aljarrah K, Iqbal J, Khalid M, Shah IH, Alanazi N. Discovery and Protein Modeling Studies of Novel Compound Mutations Causing Resistance to Multiple Tyrosine Kinase Inhibitors in Chronic Myeloid Leukemia. Asian Pac J Cancer Prev 2020; 21:3517-3526. [PMID: 33369447 PMCID: PMC8046299 DOI: 10.31557/apjcp.2020.21.12.3517] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVE BCR-ABL fusion oncogene is the hallmark of chronic myeloid leukemia (CML), causing genomic instability which leads to accumulation of mutations in BCR-ABL as well as other genes. BCR-ABL mutations are the cause of tyrosine kinase inhibitors (TKIs) resistance in CML. Recently, compound BCR-ABL mutations have been reported to resist all FDA approved TKIs. Therefore, finding novel compound BCR-ABL mutations can help and clinically manage CML. Therefore, our objective was to find out novel drug-resistant compound BCR-ABL mutations in CML and carry out their protein modelling studies. METHODOLOGY Peripheral blood samples were collected from ten imatinib resistant CML patients receiving nilotinib treatment. BCR-ABL transcript mutations were investigated by employing capillary sequencing. Patient follow-up was carried out using European LeukemiaNet guidelines. Protein modeling studies were carried out for new compound mutations using PyMol to see the effects of mutations at structural level. RESULTS A novel compound mutation (K245N mutation along with G250W mutation) and previously known T351I utation was detected in two of the nilotinib resistance CML patients respectively while in the rest of 8 nilotinib responders, no resistant mutations were detected. Protein modelling studies indicated changes in BCR-ABL mutant protein which may have negatively impacted its binding with nilotinib leading to drug resistance. CONCLUSION We report a novel nilotinib resistant BCR-ABL compound mutation (K245N along with G250W mutation) which impacts structural modification in BCR-ABL mutant protein leading to drug resistance. As compound mutations pose a new threat by causing resistance to all FDA approved tyrosine kinase inhibitors in BCR-ABL+ leukemias, our study opens a new direction for in vitro characterization of novel BCR-ABL compound mutations and their resistant to second generation and third generation TKIs.
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Affiliation(s)
- Zafar Iqbal
- Hematology Oncology and Pharmacogenetics Engineering Sciences (HOPES) Group, Health Sciences Research Laboratories, Department of Zoology, University of the Punjab, Lahore, & University of Education, Lahore, Pakistan
| | - Muhammad Absar
- Hematology Oncology and Pharmacogenetics Engineering Sciences (HOPES) Group, Health Sciences Research Laboratories, Department of Zoology, University of the Punjab, Lahore, & University of Education, Lahore, Pakistan
| | - Amer Mahmood
- Department of Anatomy, College of Medicine and King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia
| | - Aamer Aleem
- Hematology/Oncology Division, Department of Medicine, College of Medicine and King Khalid University Hospital, King Saud University, Riyadh, Saudi Arabia
| | - Mudassar Iqbal
- Foreign Faculty, Asian Medical Institute, Kant City, National Surgical Centre, Bishkek, Kyrgyzstan, and Higher Education Commission Program in "Hematology Oncology and Pharmacogenetics Engineering Sciences (HOPES)", Kyrgyzstan
| | - Abid Jameel
- Post-Graduate Medical Institute, Hayatabad Medical Complex, Peshawar, Pakistan
| | - Tanveer Akhtar
- Hematology Oncology and Pharmacogenetics Engineering Sciences (HOPES) Group, Health Sciences Research Laboratories, Department of Zoology, University of the Punjab, Lahore, & University of Education, Lahore, Pakistan
| | - Sajjad Karim
- Center of Excellence in Genomic Medicine Research & Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mahmood Rasool
- Center of Excellence in Genomic Medicine Research & Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Zeenat Mirza
- Center of Excellence in Genomic Medicine Research & Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | | | - Afia Muhammad Akram
- Department of Zoology, Division of Science and Technology, University of Education, Township, Lahore, Pakistan
| | | | - Ahmad M Khalid
- Departments of Biotechnology and Genomic Medicine, University of Sialkot, Pakistan
| | - Khalid Aljarrah
- College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS)/ KAIMRC/SSBMT, National Guards Health Affairs, Al-Ahsa, Kingdom of Saudi Arabia.,Jordan University of Science and Technology, Irbid, Jordan
| | - Janhangir Iqbal
- National Guard Health Affairs, King Abdullah International Medical Research Centre (KAIMRC), Al-Ahsa, Saudi Arabia
| | - Muhammad Khalid
- Allied Hospital, Punjab Medical College & Sahil Hospital, Faisalabad, Pakistan
| | - Ijaz H Shah
- Allied Hospital, Punjab Medical College & Sahil Hospital, Faisalabad, Pakistan
| | - Nawaf Alanazi
- College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS)/ KAIMRC/SSBMT, National Guards Health Affairs, Al-Ahsa, Kingdom of Saudi Arabia
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19
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Shi MJ, Meng XY, Fontugne J, Chen CL, Radvanyi F, Bernard-Pierrot I. Identification of new driver and passenger mutations within APOBEC-induced hotspot mutations in bladder cancer. Genome Med 2020; 12:85. [PMID: 32988402 PMCID: PMC7646471 DOI: 10.1186/s13073-020-00781-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 09/11/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND APOBEC-driven mutagenesis and functional positive selection of mutated genes may synergistically drive the higher frequency of some hotspot driver mutations compared to other mutations within the same gene, as we reported for FGFR3 S249C. Only a few APOBEC-associated driver hotspot mutations have been identified in bladder cancer (BCa). Here, we systematically looked for and characterised APOBEC-associated hotspots in BCa. METHODS We analysed 602 published exome-sequenced BCas, for part of which gene expression data were also available. APOBEC-associated hotspots were identified by motif-mapping, mutation signature fitting and APOBEC-mediated mutagenesis comparison. Joint analysis of DNA hairpin stability and gene expression was performed to predict driver or passenger hotspots. Aryl hydrocarbon receptor (AhR) activity was calculated based on its target genes expression. Effects of AhR knockout/inhibition on BCa cell viability were analysed. RESULTS We established a panel of 44 APOBEC-associated hotspot mutations in BCa, which accounted for about half of the hotspot mutations. Fourteen of them overlapped with the hotspots found in other cancer types with high APOBEC activity. They mostly occurred in the DNA lagging-strand templates and the loop of DNA hairpins. APOBEC-associated hotspots presented systematically a higher prevalence than the other mutations within each APOBEC-target gene, independently of their functional impact. A combined analysis of DNA loop stability and gene expression allowed to distinguish known passenger from known driver hotspot mutations in BCa, including loss-of-function mutations affecting tumour suppressor genes, and to predict new candidate drivers, such as AHR Q383H. We further characterised AHR Q383H as an activating driver mutation associated with high AhR activity in luminal tumours. High AhR activity was also found in tumours presenting amplifications of AHR and its co-receptor ARNT. We finally showed that BCa cells presenting those different genetic alterations were sensitive to AhR inhibition. CONCLUSIONS Our study identified novel potential drivers within APOBEC-associated hotspot mutations in BCa reinforcing the importance of APOBEC mutagenesis in BCa. It could allow a better understanding of BCa biology and aetiology and have clinical implications such as AhR as a potential therapeutic target. Our results also challenge the dogma that all hotspot mutations are drivers and mostly gain-of-function mutations affecting oncogenes.
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Affiliation(s)
- Ming-Jun Shi
- Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, 26 Rue d'Ulm, 75005, Paris, France
- Paris-Saclay University, Paris, France
| | - Xiang-Yu Meng
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, 26 Rue d'Ulm, 75005, Paris, France.
- Paris-Saclay University, Paris, France.
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China.
| | - Jacqueline Fontugne
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, 26 Rue d'Ulm, 75005, Paris, France
- Paris-Saclay University, Paris, France
| | - Chun-Long Chen
- Institut Curie, CNRS, UMR3244, PSL Research University, Paris, France
- Sorbonne Université, Paris, France
| | - François Radvanyi
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, 26 Rue d'Ulm, 75005, Paris, France
| | - Isabelle Bernard-Pierrot
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, 26 Rue d'Ulm, 75005, Paris, France.
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Targeting BMP signaling in the bone marrow microenvironment of myeloid leukemia. Biochem Soc Trans 2020; 48:411-418. [DOI: 10.1042/bst20190223] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 02/18/2020] [Accepted: 02/18/2020] [Indexed: 12/29/2022]
Abstract
The bone morphogenetic protein (BMP) pathway regulates the fate and proliferation of normal hematopoietic stem cells (HSC) as well as interactions with their niche. While BMP2 and BMP4 promote HSC differentiation, only BMP4 maintains HSC pool and favors interactions with their niche. In myeloid leukemia, we have identified intrinsic and extrinsic dysregulations of the BMP pathway in Chronic Myeloid Leukemia (CML) and Acute Myeloid leukemia (AML) responsible for leukemic stem cells (LSC) survival. In AML, BMP pathway alterations sustain and promote resistant immature-like leukemic cells by activating a new signaling cascade. Binding of BMP4 to BMPR1A leads to ΔNp73 expression, which in turn induces NANOG, altogether associated with a poor patient's prognosis. Despite efficient targeted therapies, like Tyrosine Kinase Inhibitors (TKI) in CML, many patients retain LSCs. Our laboratory demonstrated that the BMP pathway sustains a permanent pool of LSCs expressing high levels of BMPR1B receptor, that evolve upon treatment to progressively implement a BMP4 autocrine loop, leading to TKI-resistant cells. Single cell RNA-Seq analysis of TKI-persisting LSCs showed a co-enrichment of BMP with Jak2-signaling, quiescence and stem cell (SC) signatures. Using a new model of persisting LSCs, we recently demonstrated that BMPR1B+ cells display co-activated Smad1/5/8 and Stat3 pathways and could be targeted by blocking BMPR1B/Jak2 signal. Lastly, a specific BMPR1B inhibitor impaired BMP4-mediated LSC protection against TKIs. Altogether, data based on various studies including ours, indicate that BMP targeting could eliminate leukemic cells within a protective bone marrow microenvironment to efficiently impact residual resistance or persistence of LSCs in myeloid leukemia.
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Hulke ML, Massey DJ, Koren A. Genomic methods for measuring DNA replication dynamics. Chromosome Res 2020; 28:49-67. [PMID: 31848781 PMCID: PMC7131883 DOI: 10.1007/s10577-019-09624-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/30/2019] [Accepted: 12/03/2019] [Indexed: 12/27/2022]
Abstract
Genomic DNA replicates according to a defined temporal program in which early-replicating loci are associated with open chromatin, higher gene density, and increased gene expression levels, while late-replicating loci tend to be heterochromatic and show higher rates of genomic instability. The ability to measure DNA replication dynamics at genome scale has proven crucial for understanding the mechanisms and cellular consequences of DNA replication timing. Several methods, such as quantification of nucleotide analog incorporation and DNA copy number analyses, can accurately reconstruct the genomic replication timing profiles of various species and cell types. More recent developments have expanded the DNA replication genomic toolkit to assays that directly measure the activity of replication origins, while single-cell replication timing assays are beginning to reveal a new level of replication timing regulation. The combination of these methods, applied on a genomic scale and in multiple biological systems, promises to resolve many open questions and lead to a holistic understanding of how eukaryotic cells replicate their genomes accurately and efficiently.
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Affiliation(s)
- Michelle L Hulke
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Dashiell J Massey
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA
| | - Amnon Koren
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, 14853, USA.
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Shi MJ, Meng XY, Lamy P, Banday AR, Yang J, Moreno-Vega A, Chen CL, Dyrskjøt L, Bernard-Pierrot I, Prokunina-Olsson L, Radvanyi F. APOBEC-mediated Mutagenesis as a Likely Cause of FGFR3 S249C Mutation Over-representation in Bladder Cancer. Eur Urol 2019; 76:9-13. [PMID: 30975452 DOI: 10.1016/j.eururo.2019.03.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 03/21/2019] [Indexed: 12/26/2022]
Abstract
FGFR3 is one of the most frequently mutated genes in bladder cancer and a driver of an oncogenic dependency. Here we report that only the most common recurrent FGFR3 mutation, S249C (TCC→TGC), represents an APOBEC-type motif and is probably caused by the APOBEC-mediated mutagenic process, accounting for its over-representation. We observed significant enrichment of the APOBEC mutational signature and overexpression of AID/APOBEC gene family members in bladder tumors with S249C compared to tumors with other recurrent FGFR3 mutations. Analysis of replication fork directionality suggests that the coding strand of FGFR3 is predominantly replicated as a lagging strand template that could favor the formation of hairpin structures, facilitating mutagenic activity of APOBEC enzymes. In vitro APOBEC deamination assays confirmed S249 as an APOBEC target. We also found that the FGFR3 S249C mutation was common in three other cancer types with an APOBEC mutational signature, but rare in urothelial tumors without APOBEC mutagenesis and in two diseases probably related to aging. PATIENT SUMMARY: We propose that APOBEC-mediated mutagenesis can generate clinically relevant driver mutations even within suboptimal motifs, such as in the case of FGFR3 S249C, one of the most common mutations in bladder cancer. Knowledge about the etiology of this mutation will improve our understanding of the molecular mechanisms of bladder cancer.
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Affiliation(s)
- Ming-Jun Shi
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, Paris, France; Paris-Sud University, Paris-Saclay University, Paris, France; Department of Urology, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Xiang-Yu Meng
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, Paris, France; Paris-Sud University, Paris-Saclay University, Paris, France; Department of Urology, Zhongnan Hospital, Wuhan University, Wuhan, China
| | - Philippe Lamy
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - A Rouf Banday
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jie Yang
- Inserm UMR-1162, Génomique fonctionnelle des Tumeurs solides, Université Paris Diderot, Paris, France
| | - Aura Moreno-Vega
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, Paris, France; Paris-Sud University, Paris-Saclay University, Paris, France
| | - Chun-Long Chen
- Institut Curie, CNRS, UMR3244, PSL Research University, Paris, France; Sorbonne Université, Paris, France
| | - Lars Dyrskjøt
- Department of Molecular Medicine, Aarhus University Hospital, Aarhus, Denmark
| | | | - Ludmila Prokunina-Olsson
- Laboratory of Translational Genomics, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - François Radvanyi
- Institut Curie, CNRS, UMR144, Molecular Oncology team, PSL Research University, Paris, France.
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