1
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Wang Z, Qu M, Chang S, Dai X, You C. Human RNA-binding protein HNRNPD interacts with and regulates the repair of deoxyribouridine in DNA. Int J Biol Macromol 2024; 262:129951. [PMID: 38325695 DOI: 10.1016/j.ijbiomac.2024.129951] [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: 12/13/2023] [Revised: 01/31/2024] [Accepted: 02/01/2024] [Indexed: 02/09/2024]
Abstract
Deoxyribouridine (dU) is an abnormal nucleoside in DNA and plays vital roles in multiple biological and physiological processes. Here, we conducted a mass spectrometry-based screen for dU-binding proteins and found that the heterogeneous nuclear ribonucleoprotein D (HNRNPD) could preferentially bind to dU-containing DNA. We also discovered that HNRNPD engages in the 5-Fluorouracil (5FU)-induced DNA damage response and can modulate the repair of dU in DNA in vitro and in human cells. Moreover, using a shuttle vector- and next-generation sequencing-based method, we unveiled the crucial role of HNRNPD in promoting the replicative bypass of dU in human cells. Taken together, these findings suggested that HNRNPD is a novel dU-bearing DNA-binding protein capable of regulating the removal of dU in DNA, and provided new insights into the molecular mechanisms of dU-associated diseases.
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Affiliation(s)
- Ziyu Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Minghui Qu
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Sijia Chang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Xiaoxia Dai
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
| | - Changjun You
- State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
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2
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Liang Y, Yuan Q, Zheng Q, Mei Z, Song Y, Yan H, Yang J, Wu S, Yuan J, Wu W. DNA Damage Atlas: an atlas of DNA damage and repair. Nucleic Acids Res 2024; 52:D1218-D1226. [PMID: 37831087 PMCID: PMC10767978 DOI: 10.1093/nar/gkad845] [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: 08/12/2023] [Revised: 09/06/2023] [Accepted: 09/21/2023] [Indexed: 10/14/2023] Open
Abstract
DNA damage and its improper repair are the major source of genomic alterations responsible for many human diseases, particularly cancer. To aid researchers in understanding the underlying mechanisms of genome instability, a number of genome-wide profiling approaches have been developed to monitor DNA damage and repair events. The rapid accumulation of published datasets underscores the critical necessity of a comprehensive database to curate sequencing data on DNA damage and repair intermediates. Here, we present DNA Damage Atlas (DDA, http://www.bioinformaticspa.com/DDA/), the first large-scale repository of DNA damage and repair information. Currently, DDA comprises 6,030 samples from 262 datasets by 59 technologies, covering 16 species, 10 types of damage and 135 treatments. Data collected in DDA was processed through a standardized workflow, including quality checks, hotspots identification and a series of feature characterization for the hotspots. Notably, DDA encompasses analyses of highly repetitive regions, ribosomal DNA and telomere. DDA offers a user-friendly interface that facilitates browsing, searching, genome browser visualization, hotspots comparison and data downloading, enabling convenient and thorough exploration for datasets of interest. In summary, DDA will stand as a valuable resource for research in genome instability and its association with diseases.
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Affiliation(s)
- Yu Liang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Qingqing Yuan
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Qijie Zheng
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Zilv Mei
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Yawei Song
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Huan Yan
- GMU-GIBH Joint School of Life Sciences, The Guangdong-Hong Kong-Macau Joint Laboratory for Cell Fate Regulation and Diseases, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
| | - Jiajie Yang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Shuheng Wu
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Jiao Yuan
- GMU-GIBH Joint School of Life Sciences, The Guangdong-Hong Kong-Macau Joint Laboratory for Cell Fate Regulation and Diseases, Guangzhou National Laboratory, Guangzhou Medical University, Guangzhou, China
| | - Wei Wu
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
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3
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Lei Z, Meng H, Rao X, Zhao H, Yi C. Detect-seq, a chemical labeling and biotin pull-down approach for the unbiased and genome-wide off-target evaluation of programmable cytosine base editors. Nat Protoc 2023:10.1038/s41596-023-00837-4. [PMID: 37277562 DOI: 10.1038/s41596-023-00837-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 03/09/2023] [Indexed: 06/07/2023]
Abstract
Programmable cytosine base editors show promising approaches for correcting pathogenic mutations; yet, their off-target effects have been of great concern. Detect-seq (dU-detection enabled by C-to-T transition during sequencing) is an unbiased, sensitive method for the off-target evaluation of programmable cytosine base editors. It profiles the editome by tracing the editing intermediate dU, which is introduced inside living cells and edited by programmable cytosine base editors. The genomic DNA is extracted, preprocessed and labeled by successive chemical and enzymatic reactions, followed by biotin pull-down to enrich the dU-containing loci for sequencing. Here, we describe a detailed protocol for performing the Detect-seq experiment, and a customized, open-source, bioinformatic pipeline for analyzing the characteristic Detect-seq data is also provided. Unlike those previous whole-genome sequencing-based methods, Detect-seq uses an enrichment strategy and hence is endowed with great sensitivity, a higher signal-to-noise ratio and no requirement for high sequencing depth. Furthermore, Detect-seq is widely applicable for both mitotic and postmitotic biological systems. The entire protocol typically takes 5 d from the genomic DNA extraction to sequencing and ~1 week for data analysis.
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Affiliation(s)
- Zhixin Lei
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, China
| | - Haowei Meng
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Xichen Rao
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China
| | - Huanan Zhao
- School of Life Sciences, Tsinghua University, Beijing, China
- Peking University-Tsinghua University-National Institute of Biological Sciences Joint Graduate Program, School of Life Sciences, Tsinghua University, Beijing, China
| | - Chengqi Yi
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, Beijing, China.
- Department of Chemical Biology and Synthetic and Functional Biomolecules Center, College of Chemistry and Molecular Engineering, Peking University, Beijing, China.
- Peking University Genome Editing Research Center, Peking University, Beijing, China.
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4
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Ji TT, Xie NB, Ding JH, Wang M, Guo X, Chen YY, Yu SY, Feng YQ, Yuan BF. Enzymatic Cleavage-Mediated Extension Stalling Enables Accurate Recognition and Quantification of Locus-Specific Uracil Modification in DNA. Anal Chem 2023; 95:8384-8392. [PMID: 37192336 DOI: 10.1021/acs.analchem.3c01410] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Chemical modifications in DNA have profound influences on the structures and functions of DNA. Uracil, a naturally occurring DNA modification, can originate from the deamination of cytosine or arise from misincorporation of dUTP into DNA during DNA replication. Uracil in DNA will imperil genomic stability due to their potential in producing detrimental mutations. An in-depth understanding of the functions of uracil modification requires the accurate determination of its site as well as content in genomes. Herein, we characterized that a new member of the uracil-DNA glycosylase (UDG) family enzyme (UdgX-H109S) could selectively cleave both uracil-containing single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA). Based on this unique property of UdgX-H109S, we developed an enzymatic cleavage-mediated extension stalling (ECES) method for the locus-specific detection and quantification of uracil in genomic DNA. In the ECES method, UdgX-H109S specifically recognizes and cleaves the N-glycosidic bond of uracil from dsDNA and generates an apurinic/apyrimidinic (AP) site, which could be broken by APE1 to form a one-nucleotide gap. The specific cleavage by UdgX-H109S is then evaluated and quantified by qPCR. With the developed ECES approach, we demonstrated that the level of uracil at position Chr4:50566961 in genomic DNA of breast cancer tissues was significantly decreased. Collectively, the ECES method has been proved to be accurate and reproducible in the locus-specific quantification of uracil in genomic DNA from biological and clinical samples.
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Affiliation(s)
- Tong-Tong Ji
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Neng-Bin Xie
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
- School of Public Health, Research Center of Public Health, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430060, China
| | - Jiang-Hui Ding
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Min Wang
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Xia Guo
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Ying-Ying Chen
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
| | - Si-Yu Yu
- School of Public Health, Research Center of Public Health, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430060, China
| | - Yu-Qi Feng
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
- School of Public Health, Research Center of Public Health, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430060, China
| | - Bi-Feng Yuan
- College of Chemistry and Molecular Sciences, Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430071, China
- School of Public Health, Research Center of Public Health, Renmin Hospital of Wuhan University, Wuhan University, Wuhan, Hubei 430060, China
- Cancer Precision Diagnosis and Treatment and Translational Medicine Hubei Engineering Research Center, Wuhan Research Center for Infectious Diseases and Cancer, Zhongnan Hospital of Wuhan University, Chinese Academy of Medical Sciences, Wuhan, Hubei 430071, China
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5
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Tao J, Bauer DE, Chiarle R. Assessing and advancing the safety of CRISPR-Cas tools: from DNA to RNA editing. Nat Commun 2023; 14:212. [PMID: 36639728 PMCID: PMC9838544 DOI: 10.1038/s41467-023-35886-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 37.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 01/06/2023] [Indexed: 01/14/2023] Open
Abstract
CRISPR-Cas gene editing has revolutionized experimental molecular biology over the past decade and holds great promise for the treatment of human genetic diseases. Here we review the development of CRISPR-Cas9/Cas12/Cas13 nucleases, DNA base editors, prime editors, and RNA base editors, focusing on the assessment and improvement of their editing precision and safety, pushing the limit of editing specificity and efficiency. We summarize the capabilities and limitations of each CRISPR tool from DNA editing to RNA editing, and highlight the opportunities for future improvements and applications in basic research, as well as the therapeutic and clinical considerations for their use in patients.
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Affiliation(s)
- Jianli Tao
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
| | - Daniel E Bauer
- Division of Hematology/Oncology, Boston Children's Hospital, Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Stem Cell Institute, Broad Institute, Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Roberto Chiarle
- Department of Pathology, Boston Children's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
- Department of Molecular Biotechnology and Health Sciences, University of Torino, Torino, 10126, Italy.
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6
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Li CC, Liu WX, Jiang S, Liu M, Luo X, Zhang CY. Construction of Bioluminescent Sensors for Label-Free, Template-Free, Separation-Free, and Sequence-Independent Detection of both Clustered and Isolated Damage in Genomic DNA. Anal Chem 2022; 94:14716-14724. [PMID: 36223141 DOI: 10.1021/acs.analchem.2c03134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
DNA damage induced by endogenous/exogenous factors may cause various diseases, and the genomic DNA damage has become an important biomarker for clinical diagnosis and risk assessment, but it remains a great challenge to accurately quantify both clustered and isolated damage because of their random locations, large diversity, and low abundance. Herein, we demonstrate the development of bioluminescent sensors for label-free, template-free, separation-free, and sequence-independent detection of both clustered and isolated damage in genomic DNA based on the base-excision repair (BER) pathway and terminal transferase (TdT)-initiated template-free isothermal cyclic amplification. The damaged bases are cleaved by DNA glycosylase to generate a new 3'-OH terminus, and subsequently, TdT catalyzes the repeated incorporation of dTTPs into the 3'-OH terminus to produce poly-T structures which can hybridize with the signal probe to form a poly-T sequence/signal probe duplex. Under the lambda exonuclease hydrolysis, a large number of adenosine monophosphate (AMP) molecules are produced to generate a high bioluminescence signal through the cyclic interconversion of AMP-adenosine triphosphate (ATP)-AMP in the presence of luciferin and firefly luciferase. Moreover, the introduction of APE1-induced cyclic cleavage signal amplification can greatly improve the detection sensitivity. The proposed strategy can detect both clustered and isolated damage in genomic DNA with extremely high sensitivity and excellent specificity, and it can even distinguish 0.001% DNA damage in the mixture. Importantly, it can detect the cellular DNA damage with a detection limit of 0.011 ng and further extend to measure various DNA damage with the integration of appropriate DNA repair enzymes.
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Affiliation(s)
- Chen-Chen Li
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China.,Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Wan-Xin Liu
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China.,Zichuan Experimental Middle School, Zibo 255100, China
| | - Su Jiang
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China
| | - Meng Liu
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China
| | - Xiliang Luo
- Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, MOE, Shandong Key Laboratory of Biochemical Analysis, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Chun-Yang Zhang
- College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan 250014, China
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7
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Li X, Wang Y, Tang H, Yang B, Zhao Y, Wu P. Evaluation of the sequence-dependent relative activity of APE1 for optimal biosensing design. Biosens Bioelectron 2022; 214:114539. [DOI: 10.1016/j.bios.2022.114539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/01/2022] [Indexed: 11/02/2022]
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8
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Zheng X, Chen D, Zhao Y, Dai X, You C. Development of an Endonuclease V-Assisted Analytical Method for Sequencing Analysis of Deoxyinosine in DNA. Anal Chem 2022; 94:11627-11632. [PMID: 35942621 DOI: 10.1021/acs.analchem.2c02126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Deoxyinosine (dI) is a highly mutagenic lesion that preferentially pairs with deoxycytidine during replication, which may induce A to G transition and ultimately contribute to carcinogenesis. Therefore, finding the site of dI modification in DNA is of great value for both basic research and clinical applications. Herein, we developed a novel method to sequence the dI modification site in DNA, which utilizes endonuclease V (EndoV)-dependent deamination repair to specifically label the modification site with biotin-14-dATP that allows the affinity enrichment of dI-bearing DNA for sequencing. We have achieved efficient determination of the location of the modified nucleotide in dI-bearing plasmid DNA with the assistance of EndoV-dependent deamination repair. We have also successfully applied this approach to locate the dI modification sites in the mitochondrial DNA of human cells. Our method should be generally applicable for genome-wide sequencing analysis of dI modifications in living organisms.
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Affiliation(s)
- Xiaofang Zheng
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Hunan University, Changsha 410082, China
| | - Di Chen
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Hunan University, Changsha 410082, China
| | - Yingqi Zhao
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Hunan University, Changsha 410082, China
| | - Xiaoxia Dai
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Hunan University, Changsha 410082, China
| | - Changjun You
- Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan Provincial Key Laboratory of Biomacromolecular Chemical Biology, Hunan University, Changsha 410082, China
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9
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Mitochondrial base editor induces substantial nuclear off-target mutations. Nature 2022; 606:804-811. [PMID: 35551512 DOI: 10.1038/s41586-022-04836-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 05/05/2022] [Indexed: 11/08/2022]
Abstract
DddA-derived cytosine base editors (DdCBEs), which are fusions of the split-DddA halves and transcription activator-like effector (TALE) array proteins, enable targeted C·G-to- T·A conversions in mitochondrial DNA1. However, its genome-wide specificity is poorly understood. Here we show that the mitochondrial base editor induces extensive off-target editing in the nuclear genome. Genome-wide, unbiased analysis of its editome reveals hundreds of off-target sites that are TALE array sequence (TAS)-dependent or -independent. TAS-dependent off-target sites in the nuclear DNA (nDNA) are often specified by only one of the two TALE repeats, challenging the principle that DdCBEs are guided by a paired TALE proteins positioned in close proximity. TAS-independent nDNA off-target sites are frequently shared among DdCBEs with distinct TALE arrays. Notably, they co-localize strongly with CTCF-binding sites and are enriched in TAD boundaries. We also engineered DdCBE to alleviate such off-target effect. Collectively, our results have implications for the use of DdCBEs in basic research and therapeutic applications, and suggest the need to thoroughly define and evaluate the off-target effects of base editing tools.
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10
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Jiang L, Yin J, Qian M, Rong S, Zhang S, Chen K, Zhao C, Tan Y, Guo J, Chen H, Gao S, Liu T, Liu Y, Shen B, Yang J, Zhang Y, Meng FL, Hu J, Ma H, Chen YH. UdgX-Mediated Uracil Sequencing at Single-Nucleotide Resolution. J Am Chem Soc 2022; 144:1323-1331. [PMID: 35037455 DOI: 10.1021/jacs.1c11269] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
As an aberrant base in DNA, uracil is generated by either deoxyuridine (dU) misincorporation or cytosine deamination, and involved in multiple physiological and pathological processes. Genome-wide profiles of uracil are important for study of these processes. Current methods for whole-genome mapping of uracil all rely on uracil-DNA N-glycosylase (UNG) and are limited in resolution, specificity, and/or sensitivity. Here, we developed a UdgX cross-linking and polymerase stalling sequencing ("Ucaps-seq") method to detect dU at single-nucleotide resolution. First, the specificity of Ucaps-seq was confirmed on synthetic DNA. Then the effectiveness of the approach was verified on two genomes from different sources. Ucaps-seq not only identified the enrichment of dU at dT sites in pemetrexed-treated cancer cells with globally elevated uracil but also detected dU at dC sites within the "WRC" motif in activated B cells which have increased dU in specific regions. Finally, Ucaps-seq was utilized to detect dU introduced by the cytosine base editor (nCas9-APOBEC) and identified a novel off-target site in cellular context. In conclusion, Ucaps-seq is a powerful tool with many potential applications, especially in evaluation of base editing fidelity.
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Affiliation(s)
- Liudan Jiang
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Shanghai Fifth People's Hospital, Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Jiayong Yin
- Institute of Pediatrics and Department of Hematology and Oncology, Children's Hospital of Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Maoxiang Qian
- Institute of Pediatrics and Department of Hematology and Oncology, Children's Hospital of Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Shaoqin Rong
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Shengqi Zhang
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Kejing Chen
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Chengchen Zhao
- School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Yuanqing Tan
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Jiayin Guo
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Hao Chen
- School of Medicine, Southern University of Science and Technology, Shenzhen 518055, China
| | - Siyun Gao
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Tingting Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yi Liu
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Bin Shen
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 211166, China
| | - Jian Yang
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
| | - Yong Zhang
- School of Life Science and Technology, Tongji University, Shanghai, 200092, China
| | - Fei-Long Meng
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai 200031, China
| | - Jinchuan Hu
- Shanghai Fifth People's Hospital, Fudan University, and Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism (Ministry of Science and Technology), Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China
| | - Honghui Ma
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China.,Research Units of Origin and Regulation of Heart Rhythm, Chinese Academy of Medical Sciences, Shanghai 200092, China
| | - Yi-Han Chen
- Department of Cardiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai 200120, China.,Key Laboratory of Arrhythmias of the Ministry of Education of China, Tongji University School of Medicine, Shanghai, 200092, China
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11
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Tang F, Yuan J, Yuan BF, Wang Y. DNA-Protein Cross-Linking Sequencing for Genome-Wide Mapping of Thymidine Glycol. J Am Chem Soc 2022; 144:454-462. [PMID: 34978433 PMCID: PMC8755629 DOI: 10.1021/jacs.1c10490] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Thymidine glycol (Tg) is the most prevalent form of oxidatively induced pyrimidine lesions in DNA. Tg can arise from direct oxidation of thymidine in DNA. In addition, 5-methyl-2'-deoxycytidine (5-mdC) can be oxidized to 5-mdC glycol, and its subsequent deamination also yields Tg. However, Tg's distribution in the human genome remains unknown. Here, we presented a DNA-protein cross-linking sequencing (DPC-Seq) method for genome-wide mapping of Tg in human cells. Our approach capitalizes on the specificity of a bifunctional DNA glycosylase, i.e., NTHL1, for the covalent labeling, as well as DPC pulldown, SDS-PAGE fractionation, and membrane transfer for highly efficient and selective enrichment of Tg-bearing DNA. By employing DPC-Seq, we detected thousands of Tg sites in the human genome, where dual ablation of NTHL1 and NEIL1, the major DNA glycosylases responsible for Tg repair, led to pronounced increases in the number of Tg peaks. In addition, Tg is depleted in genomic regions associated with active transcription but enriched at nucleosome-binding sites, especially at heterochromatin sites marked with H3K9me2. Collectively, we developed a DPC-Seq method for highly efficient enrichment of Tg-containing DNA and for genome-wide mapping of Tg in human cells. Our work offers a robust tool for future functional studies of Tg in DNA, and we envision that the method can also be adapted for mapping other modified nucleosides in genomic DNA in the future.
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Affiliation(s)
- Feng Tang
- Department of Chemistry, University of California, Riverside, Riverside, California 92521-0403, United States,Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University, Wuhan 430072, China
| | - Jun Yuan
- Department of Chemistry, University of California, Riverside, Riverside, California 92521-0403, United States
| | - Bi-Feng Yuan
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University, Wuhan 430072, China
| | - Yinsheng Wang
- Department of Chemistry, University of California, Riverside, Riverside, California 92521-0403, United States
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12
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Fiddler JL, Xiu Y, Blum JE, Lamarre SG, Phinney WN, Stabler SP, Brosnan ME, Brosnan JT, Thalacker-Mercer AE, Field MS. Reduced Shmt2 Expression Impairs Mitochondrial Folate Accumulation and Respiration, and Leads to Uracil Accumulation in Mouse Mitochondrial DNA. J Nutr 2021; 151:2882-2893. [PMID: 34383924 DOI: 10.1093/jn/nxab211] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/24/2021] [Accepted: 06/08/2021] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Adequate cellular thymidylate (dTMP) pools are essential for preservation of nuclear and mitochondrial genome stability. Previous studies have indicated that disruption in nuclear dTMP synthesis leads to increased uracil misincorporation into DNA, affecting genome stability. To date, the effects of impaired mitochondrial dTMP synthesis in nontransformed tissues have been understudied. OBJECTIVES This study aimed to determine the effects of decreased serine hydroxymethyltransferase 2 (Shmt2) expression and dietary folate deficiency on mitochondrial DNA (mtDNA) integrity and mitochondrial function in mouse tissues. METHODS Liver mtDNA content, and uracil content in liver mtDNA, were measured in Shmt2+/- and Shmt2+/+ mice weaned onto either a folate-sufficient control diet (2 mg/kg folic acid; C) or a modified diet lacking folic acid (0 mg/kg folic acid) for 7 wk. Shmt2+/- and Shmt2+/+ mouse embryonic fibroblast (MEF) cells were cultured in defined culture medium containing either 0 or 25 nM folate (6S-5-formyl-tetrahydrofolate, folinate) to assess proliferative capacity and mitochondrial function. Chi-square tests, linear mixed models, and 2-factor ANOVA with Tukey post hoc analyses were used to analyze data. RESULTS Shmt2 +/- mice exhibited a 48%-67% reduction in SHMT2 protein concentrations in tissues. Interestingly, Shmt2+/- mice consuming the folate-sufficient C diet exhibited a 25% reduction in total folate in liver mitochondria. There was also a >20-fold increase in uracil in liver mtDNA in Shmt2+/- mice consuming the C diet, and dietary folate deficiency also increased uracil content in mouse liver mtDNA from both Shmt2+/+ and Shmt2+/- mice. Furthermore, decreased Shmt2 expression in MEF cells reduced cell proliferation, mitochondrial membrane potential, and oxygen consumption rate. CONCLUSIONS This study demonstrates that Shmt2 heterozygosity and dietary folate deficiency impair mitochondrial dTMP synthesis in mice, as evidenced by the increased uracil in mtDNA. In addition, Shmt2 heterozygosity impairs mitochondrial function in MEF cells. These findings suggest that elevated uracil in mtDNA may impair mitochondrial function.
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Affiliation(s)
- Joanna L Fiddler
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Yuwen Xiu
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Jamie E Blum
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Simon G Lamarre
- Department of Biology, University of Moncton, Moncton, New Brunswick, Canada
| | | | - Sally P Stabler
- Department of Medicine, University of Colorado, Aurora, CO, USA
| | - Margaret E Brosnan
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - John T Brosnan
- Department of Biochemistry, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Anna E Thalacker-Mercer
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Martha S Field
- Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
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13
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Genome-wide mapping of genomic DNA damage: methods and implications. Cell Mol Life Sci 2021; 78:6745-6762. [PMID: 34463773 PMCID: PMC8558167 DOI: 10.1007/s00018-021-03923-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 08/02/2021] [Accepted: 08/11/2021] [Indexed: 12/19/2022]
Abstract
Exposures from the external and internal environments lead to the modification of genomic DNA, which is implicated in the cause of numerous diseases, including cancer, cardiovascular, pulmonary and neurodegenerative diseases, together with ageing. However, the precise mechanism(s) linking the presence of damage, to impact upon cellular function and pathogenesis, is far from clear. Genomic location of specific forms of damage is likely to be highly informative in understanding this process, as the impact of downstream events (e.g. mutation, microsatellite instability, altered methylation and gene expression) on cellular function will be positional—events at key locations will have the greatest impact. However, until recently, methods for assessing DNA damage determined the totality of damage in the genomic location, with no positional information. The technique of “mapping DNA adductomics” describes the molecular approaches that map a variety of forms of DNA damage, to specific locations across the nuclear and mitochondrial genomes. We propose that integrated comparison of this information with other genome-wide data, such as mutational hotspots for specific genotoxins, tumour-specific mutation patterns and chromatin organisation and transcriptional activity in non-cancerous lesions (such as nevi), pre-cancerous conditions (such as polyps) and tumours, will improve our understanding of how environmental toxins lead to cancer. Adopting an analogous approach for non-cancer diseases, including the development of genome-wide assays for other cellular outcomes of DNA damage, will improve our understanding of the role of DNA damage in pathogenesis more generally.
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14
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Feng Y, Chen JJ, Xie NB, Ding JH, You XJ, Tao WB, Zhang X, Yi C, Zhou X, Yuan BF, Feng YQ. Direct decarboxylation of ten-eleven translocation-produced 5-carboxylcytosine in mammalian genomes forms a new mechanism for active DNA demethylation. Chem Sci 2021; 12:11322-11329. [PMID: 34567494 PMCID: PMC8409474 DOI: 10.1039/d1sc02161c] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 07/20/2021] [Indexed: 12/26/2022] Open
Abstract
DNA cytosine methylation (5-methylcytosine, 5mC) is the most important epigenetic mark in higher eukaryotes. 5mC in genomes is dynamically controlled by writers and erasers. DNA (cytosine-5)-methyltransferases (DNMTs) are responsible for the generation and maintenance of 5mC in genomes. Active demethylation of 5-methylcytosine (5mC) is achieved by ten-eleven translocation (TET) dioxygenase-mediated oxidation of 5mC to 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), and 5-carboxylcytosine (5caC). 5fC and 5caC are further processed by thymine DNA glycosylase (TDG)-initiated base excision repair (BER) to restore unmodified cytosines. The TET-TDG-BER pathway could cause the production of DNA strand breaks and therefore jeopardize the integrity of genomes. Here, we investigated the direct decarboxylation of 5caC in mammalian genomes by using metabolic labeling with 2'-fluorinated 5caC (F-5caC) and mass spectrometry analysis. Our results clearly demonstrated the decarboxylation of 5caC occurring in mammalian genomes, which unveiled that, in addition to the TET-TDG-BER pathway, the direct decarboxylation of TET-produced 5caC constituted a new pathway for active demethylation of 5mC in mammalian genomes.
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Affiliation(s)
- Yang Feng
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China .,School of Health Sciences, Wuhan University Wuhan 430071 China
| | - Juan-Juan Chen
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Neng-Bin Xie
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Jiang-Hui Ding
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Xue-Jiao You
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Wan-Bing Tao
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Xiaoxue Zhang
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University Beijing 100871 China
| | - Chengqi Yi
- State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University Beijing 100871 China
| | - Xiang Zhou
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China
| | - Bi-Feng Yuan
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China .,School of Health Sciences, Wuhan University Wuhan 430071 China
| | - Yu-Qi Feng
- Sauvage Center for Molecular Sciences, Department of Chemistry, Wuhan University Wuhan 430072 China .,School of Health Sciences, Wuhan University Wuhan 430071 China
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15
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Wang Y, Zhang X, Han S, Yang W, Chen Z, Wu F, Liu J, Weng X, Zhou X. Base-Resolution Analysis of Deoxyuridine at the Genome Scale Based on the Artificial Incorporation Modified Nucleobase. ACS CENTRAL SCIENCE 2021; 7:973-979. [PMID: 34235258 PMCID: PMC8227591 DOI: 10.1021/acscentsci.0c01504] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Indexed: 05/11/2023]
Abstract
Deamination of cytosine and dUMP misincorporation have been found to be capable of producing uracil in the genome. This study presents the AI-seq (artificial incorporation modified nucleobase for sequencing), a "base substitution", which not only is capable of profiling uracil at single-nucleotide resolution and showing its centromeric enrichment but could also reveal that the identified uracil sites are derived from cytosine deamination. All the results indicate the potential biological significance of uracil as the epigenetic modification.
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Affiliation(s)
- Yafen Wang
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Xiong Zhang
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Shaoqing Han
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Wei Yang
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Zonggui Chen
- State
Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Innovation Academy for
Seed Design, Chinese Academy of Sciences, Wuhan 430072, China
| | - Fan Wu
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Jizhou Liu
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
| | - Xiaocheng Weng
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
- E-mail:
| | - Xiang Zhou
- College
of Chemistry and Molecular Sciences, Key Laboratory of Biomedical
Polymers of Ministry of Education, Wuhan
University, Wuhan, 430072 Hubei, China
- E-mail:
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16
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Detect-seq reveals out-of-protospacer editing and target-strand editing by cytosine base editors. Nat Methods 2021; 18:643-651. [PMID: 34099937 DOI: 10.1038/s41592-021-01172-w] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 05/03/2021] [Indexed: 02/04/2023]
Abstract
Cytosine base editors (CBEs) have the potential to correct human pathogenic point mutations. However, their genome-wide specificity remains poorly understood. Here we report Detect-seq for the evaluation of CBE specificity. It enables sensitive detection of CBE-induced off-target sites at the genome-wide level. Detect-seq leverages chemical labeling and biotin pulldown to trace the editing intermediate deoxyuridine, thereby revealing the editome of CBE. In addition to Cas9-independent and typical Cas9-dependent off-target sites, we discovered edits outside the protospacer sequence (that is, out-of-protospacer) and on the target strand (which pairs with the single-guide RNA). Such unexpected off-target edits are prevalent and can exhibit a high editing ratio, while their occurrences exhibit cell-type dependency and cannot be predicted based on the sgRNA sequence. Moreover, we found out-of-protospacer and target-strand edits nearby the on-target sites tested, challenging the general knowledge that CBEs do not induce proximal off-target mutations. Collectively, our approaches allow unbiased analysis of the CBE editome and provide a widely applicable tool for specificity evaluation of various emerging genome editing tools.
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17
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Detection of Genomic Uracil Patterns. Int J Mol Sci 2021; 22:ijms22083902. [PMID: 33918885 PMCID: PMC8070346 DOI: 10.3390/ijms22083902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 03/28/2021] [Accepted: 04/05/2021] [Indexed: 01/06/2023] Open
Abstract
The appearance of uracil in the deoxyuridine moiety of DNA is among the most frequently occurring genomic modifications. Three different routes can result in genomic uracil, two of which do not require specific enzymes: spontaneous cytosine deamination due to the inherent chemical reactivity of living cells, and thymine-replacing incorporation upon nucleotide pool imbalances. There is also an enzymatic pathway of cytosine deamination with multiple DNA (cytosine) deaminases involved in this process. In order to describe potential roles of genomic uracil, it is of key importance to utilize efficient uracil-DNA detection methods. In this review, we provide a comprehensive and critical assessment of currently available uracil detection methods with special focus on genome-wide mapping solutions. Recent developments in PCR-based and in situ detection as well as the quantitation of genomic uracil are also discussed.
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18
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Wang B, Chen Y, Zhang X, Jiang Z, Wang Y, Chen K, Wang F, Weng X, Zhou X. A far-red emissive two-photon fluorescent probe for quantification of uracil in genomic DNA. Chem Commun (Camb) 2021; 57:2784-2787. [PMID: 33599665 DOI: 10.1039/d1cc00016k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report a new method for dU detection in genomic DNA combined with UNG excision and fluorescent probe labeling. UNG can remove uracil bases to introduce abasic sites, which can react with NRNO to produce intense fluorescence because of the inhibition of the PET effect. It can also cause the polymerase extension to stop to provide details of dU site information.
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Affiliation(s)
- Bingyao Wang
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Yi Chen
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Xiong Zhang
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Zhuoran Jiang
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Yafen Wang
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Kun Chen
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Fang Wang
- Wuhan University School of Pharmaceutical Sciences, Wuhan, 430071, China
| | - Xiaocheng Weng
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
| | - Xiang Zhou
- The Institute of Advanced Studies, College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, China.
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19
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Bogdanov KV, Merzlikina OV, Mirolyubova YV, Girshova LL, Lomaia EG, Zaritskey AY. CASC5 Gene Expression Changes Correlate with Targeted Mutations in Leukemia. Mol Biol 2021. [DOI: 10.1134/s0026893321010027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Stewart JA, Schauer G, Bhagwat AS. Visualization of uracils created by APOBEC3A using UdgX shows colocalization with RPA at stalled replication forks. Nucleic Acids Res 2020; 48:e118. [PMID: 33074285 PMCID: PMC7672425 DOI: 10.1093/nar/gkaa845] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 09/11/2020] [Accepted: 09/18/2020] [Indexed: 12/19/2022] Open
Abstract
The AID/APOBEC enzymes deaminate cytosines in single-stranded DNA (ssDNA) and play key roles in innate and adaptive immunity. The resulting uracils cause mutations and strand breaks that inactivate viruses and diversify antibody repertoire. Mutational evidence suggests that two members of this family, APOBEC3A (A3A) and APOBEC3B, deaminate cytosines in the lagging-strand template during replication. To obtain direct evidence for the presence of these uracils, we engineered a protein that covalently links to DNA at uracils, UdgX, for mammalian expression and immunohistochemistry. We show that UdgX strongly prefers uracils in ssDNA over those in U•G or U:A pairs, and localizes to nuclei in a dispersed form. When A3A is expressed in these cells, UdgX tends to form foci. The treatment of cells with cisplatin, which blocks replication, causes a significant increase in UdgX foci. Furthermore, this protein- and hence the uracils created by A3A- colocalize with replication protein A (RPA), but not with A3A. Using purified proteins, we confirm that RPA inhibits A3A by binding ssDNA, but despite its overexpression following cisplatin treatment, RPA is unable to fully protect ssDNA created by cisplatin adducts. This suggests that cisplatin treatment of cells expressing APOBEC3A should cause accumulation of APOBEC signature mutations.
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Affiliation(s)
- Jessica A Stewart
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA
| | - Grant Schauer
- Department of Biochemistry & Molecular Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Ashok S Bhagwat
- Department of Chemistry, Wayne State University, Detroit, MI 48202, USA.,Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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21
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Housh K, Jha JS, Haldar T, Amin SBM, Islam T, Wallace A, Gomina A, Guo X, Nel C, Wyatt JW, Gates KS. Formation and repair of unavoidable, endogenous interstrand cross-links in cellular DNA. DNA Repair (Amst) 2020; 98:103029. [PMID: 33385969 DOI: 10.1016/j.dnarep.2020.103029] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 11/24/2020] [Indexed: 02/08/2023]
Abstract
Genome integrity is essential for life and, as a result, DNA repair systems evolved to remove unavoidable DNA lesions from cellular DNA. Many forms of life possess the capacity to remove interstrand DNA cross-links (ICLs) from their genome but the identity of the naturally-occurring, endogenous substrates that drove the evolution and retention of these DNA repair systems across a wide range of life forms remains uncertain. In this review, we describe more than a dozen chemical processes by which endogenous ICLs plausibly can be introduced into cellular DNA. The majority involve DNA degradation processes that introduce aldehyde residues into the double helix or reactions of DNA with endogenous low molecular weight aldehyde metabolites. A smaller number of the cross-linking processes involve reactions of DNA radicals generated by oxidation.
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Affiliation(s)
- Kurt Housh
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Jay S Jha
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Tuhin Haldar
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Saosan Binth Md Amin
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Tanhaul Islam
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Amanda Wallace
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Anuoluwapo Gomina
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Xu Guo
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Christopher Nel
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Jesse W Wyatt
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States
| | - Kent S Gates
- University of Missouri, Department of Chemistry, 125 Chemistry Building, Columbia, MO 65211, United States; University of Missouri, Department of Biochemistry, Columbia, MO 65211, United States.
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22
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Abstract
Cellular DNA is constantly chemically altered by exogenous and endogenous agents. As all processes of life depend on the transmission of the genetic information, multiple biological processes exist to ensure genome integrity. Chemically damaged DNA has been linked to cancer and aging, therefore it is of great interest to map DNA damage formation and repair to elucidate the distribution of damage on a genome-wide scale. While the low abundance and inability to enzymatically amplify DNA damage are obstacles to genome-wide sequencing, new developments in the last few years have enabled high-resolution mapping of damaged bases. Recently, a number of DNA damage sequencing library construction strategies coupled to new data analysis pipelines allowed the mapping of specific DNA damage formation and repair at high and single nucleotide resolution. Strikingly, these advancements revealed that the distribution of DNA damage is heavily influenced by chromatin states and the binding of transcription factors. In the last seven years, these novel approaches have revealed new genomic maps of DNA damage distribution in a variety of organisms as generated by diverse chemical and physical DNA insults; oxidative stress, chemotherapeutic drugs, environmental pollutants, and sun exposure. Preferred sequences for damage formation and repair have been elucidated, thus making it possible to identify persistent weak spots in the genome as locations predicted to be vulnerable for mutation. As such, sequencing DNA damage will have an immense impact on our ability to elucidate mechanisms of disease initiation, and to evaluate and predict the efficacy of chemotherapeutic drugs.
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Affiliation(s)
- Cécile Mingard
- Department of Health Sciences and Technology, ETH Zürich, Schmelzbergstrasse 9, 8092 Zürich, Switzerland.
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23
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Pálinkás HL, Békési A, Róna G, Pongor L, Papp G, Tihanyi G, Holub E, Póti Á, Gemma C, Ali S, Morten MJ, Rothenberg E, Pagano M, Szűts D, Győrffy B, Vértessy BG. Genome-wide alterations of uracil distribution patterns in human DNA upon chemotherapeutic treatments. eLife 2020; 9:e60498. [PMID: 32956035 PMCID: PMC7505663 DOI: 10.7554/elife.60498] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 08/23/2020] [Indexed: 12/17/2022] Open
Abstract
Numerous anti-cancer drugs perturb thymidylate biosynthesis and lead to genomic uracil incorporation contributing to their antiproliferative effect. Still, it is not yet characterized if uracil incorporations have any positional preference. Here, we aimed to uncover genome-wide alterations in uracil pattern upon drug treatments in human cancer cell line models derived from HCT116. We developed a straightforward U-DNA sequencing method (U-DNA-Seq) that was combined with in situ super-resolution imaging. Using a novel robust analysis pipeline, we found broad regions with elevated probability of uracil occurrence both in treated and non-treated cells. Correlation with chromatin markers and other genomic features shows that non-treated cells possess uracil in the late replicating constitutive heterochromatic regions, while drug treatment induced a shift of incorporated uracil towards segments that are normally more active/functional. Data were corroborated by colocalization studies via dSTORM microscopy. This approach can be applied to study the dynamic spatio-temporal nature of genomic uracil.
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Affiliation(s)
- Hajnalka L Pálinkás
- Genome Metabolism Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
- Doctoral School of Multidisciplinary Medical Science, University of SzegedSzegedHungary
| | - Angéla Békési
- Genome Metabolism Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
| | - Gergely Róna
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
- Department of Biochemistry and Molecular Pharmacology, New York University School of MedicineNew YorkUnited States
- Perlmutter Cancer Center, New York University School of MedicineNew YorkUnited States
- Howard Hughes Medical Institute, New York University School of MedicineNew YorkUnited States
| | - Lőrinc Pongor
- Cancer Biomarker Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Bioinformatics and 2nd Department of Pediatrics, Semmelweis UniversityBudapestHungary
| | - Gábor Papp
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
| | - Gergely Tihanyi
- Genome Metabolism Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
| | - Eszter Holub
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
| | - Ádám Póti
- Genome Stability Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
| | - Carolina Gemma
- Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital CampusLondonUnited Kingdom
| | - Simak Ali
- Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital CampusLondonUnited Kingdom
| | - Michael J Morten
- Department of Biochemistry and Molecular Pharmacology, New York University School of MedicineNew YorkUnited States
| | - Eli Rothenberg
- Department of Biochemistry and Molecular Pharmacology, New York University School of MedicineNew YorkUnited States
| | - Michele Pagano
- Department of Biochemistry and Molecular Pharmacology, New York University School of MedicineNew YorkUnited States
- Perlmutter Cancer Center, New York University School of MedicineNew YorkUnited States
- Howard Hughes Medical Institute, New York University School of MedicineNew YorkUnited States
| | - Dávid Szűts
- Genome Stability Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
| | - Balázs Győrffy
- Cancer Biomarker Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Bioinformatics and 2nd Department of Pediatrics, Semmelweis UniversityBudapestHungary
| | - Beáta G Vértessy
- Genome Metabolism Research Group, Institute of Enzymology, Research Centre for Natural SciencesBudapestHungary
- Department of Applied Biotechnology and Food Sciences, Budapest University of Technology and EconomicsBudapestHungary
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24
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Leung J, Gaudin V. Who Rules the Cell? An Epi-Tale of Histone, DNA, RNA, and the Metabolic Deep State. FRONTIERS IN PLANT SCIENCE 2020; 11:181. [PMID: 32194593 PMCID: PMC7066317 DOI: 10.3389/fpls.2020.00181] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Accepted: 02/06/2020] [Indexed: 05/23/2023]
Abstract
Epigenetics refers to the mode of inheritance independent of mutational changes in the DNA. Early evidence has revealed methylation, acetylation, and phosphorylation of histones, as well as methylation of DNA as part of the underlying mechanisms. The recent awareness that many human diseases have in fact an epigenetic basis, due to unbalanced diets, has led to a resurgence of interest in how epigenetics might be connected with, or even controlled by, metabolism. The Next-Generation genomic technologies have now unleashed torrents of results exposing a wondrous array of metabolites that are covalently attached to selective sites on histones, DNA and RNA. Metabolites are often cofactors or targets of chromatin-modifying enzymes. Many metabolites themselves can be acetylated or methylated. This indicates that the acetylome and methylome can actually be deep and pervasive networks to ensure the nuclear activities are coordinated with the metabolic status of the cell. The discovery of novel histone marks also raises the question on the types of pathways by which their corresponding metabolites are replenished, how they are corralled to the specific histone residues and how they are recognized. Further, atypical cytosines and uracil have also been found in eukaryotic genomes. Although these new and extensive connections between metabolism and epigenetics have been established mostly in animal models, parallels must exist in plants, inasmuch as many of the basic components of chromatin and its modifying enzymes are conserved. Plants are chemical factories constantly responding to stress. Plants, therefore, should lend themselves readily for identifying new endogenous metabolites that are also modulators of nuclear activities in adapting to stress.
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Affiliation(s)
- Jeffrey Leung
- Institut Jean-Pierre Bourgin, ERL3559 CNRS, INRAE, Versailles, France
| | - Valérie Gaudin
- Institut Jean-Pierre Bourgin, UMR1318 INRAE-AgroParisTech, Université Paris-Saclay, Versailles, France
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25
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Chen F, Xue J, Zhang J, Bai M, Yu X, Fan C, Zhao Y. Differentiated Visualization of Single-Cell 5-Hydroxymethylpyrimidines with Microfluidic Hydrogel Encoding. J Am Chem Soc 2020; 142:2889-2896. [PMID: 31986025 DOI: 10.1021/jacs.9b11393] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
5-Hydroxymethyluracil ( 5hmU ) is found in the genomes of a diverse range of organisms as another kind of 5-hydroxymethylpyrimidine, with the exception of 5-hydroxymethylcytosine ( 5hmC ). The biological function of 5hmU has not been well explored due to lacking both specific 5hmU recognition and single-cell analysis methods. Here we report differentiated visualization of single-cell 5hmU and 5hmC with microfluidic hydrogel encoding (sc 5hmU / 5hmC -microgel). Single cells and their genomic DNA after cell lysis can be encapsulated in individual agarose microgels. The 5hmU sites are then specifically labeled with thiophosphate for the first time, followed by labeling 5hmC with azide glucose. These labeled bases are each encoded into respective DNA barcode primers by chemical cross-linking. In situ amplification is triggered for single-molecule fluorescence visualization of single-cell 5hmU and 5hmC . On the basis of the sc 5hmU / 5hmC -microgel, we reveal cell type-specific molecular signatures of these two bases with remarkable single-cell heterogeneity. Utilizing machine learning algorithms to decode four-dimensional signatures of 5hmU / 5hmC , we visualize the discrimination of nontumorigenic, carcinoma and highly invasive breast cell lines. This strategy provides a new route to analyze and decode single-cell DNA epigenetic modifications.
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Affiliation(s)
- Feng Chen
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
| | - Jing Xue
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
| | - Jin Zhang
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
| | - Min Bai
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
| | - Xu Yu
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
| | - Chunhai Fan
- Institute of Molecular Medicine, Renji Hospital, School of Medicine and School of Chemistry and ChemicalEngineering , Shanghai Jiao Tong University , Shanghai 200127 , P. R. China
| | - Yongxi Zhao
- Institute of Analytical Chemistry and Instrument for Life Science, The Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology , Xi'an Jiaotong University , Xianning West Road , Xi'an , Shaanxi 710049 , P. R. China
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26
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Sarno A, Lundbæk M, Liabakk NB, Aas PA, Mjelle R, Hagen L, Sousa MML, Krokan HE, Kavli B. Uracil-DNA glycosylase UNG1 isoform variant supports class switch recombination and repairs nuclear genomic uracil. Nucleic Acids Res 2019; 47:4569-4585. [PMID: 30838409 PMCID: PMC6511853 DOI: 10.1093/nar/gkz145] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 01/18/2019] [Accepted: 02/25/2019] [Indexed: 11/23/2022] Open
Abstract
UNG is the major uracil-DNA glycosylase in mammalian cells and is involved in both error-free base excision repair of genomic uracil and mutagenic uracil-processing at the antibody genes. However, the regulation of UNG in these different processes is currently not well understood. The UNG gene encodes two isoforms, UNG1 and UNG2, each possessing unique N-termini that mediate translocation to the mitochondria and the nucleus, respectively. A strict subcellular localization of each isoform has been widely accepted despite a lack of models to study them individually. To determine the roles of each isoform, we generated and characterized several UNG isoform-specific mouse and human cell lines. We identified a distinct UNG1 isoform variant that is targeted to the cell nucleus where it supports antibody class switching and repairs genomic uracil. We propose that the nuclear UNG1 variant, which in contrast to UNG2 lacks a PCNA-binding motif, may be specialized to act on ssDNA through its ability to bind RPA. RPA-coated ssDNA regions include both transcribed antibody genes that are targets for deamination by AID and regions in front of the moving replication forks. Our findings provide new insights into the function of UNG isoforms in adaptive immunity and DNA repair.
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Affiliation(s)
- Antonio Sarno
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.,Clinic of Laboratory Medicine, St. Olav's Hospital, Trondheim University Hospital, NO-7006 Trondheim, Norway.,PROMEC Core Facility for Proteomics and Modomics at NTNU and the Central Norway Regional Health Authority
| | - Marie Lundbæk
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Nina Beate Liabakk
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Per Arne Aas
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Robin Mjelle
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Lars Hagen
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.,PROMEC Core Facility for Proteomics and Modomics at NTNU and the Central Norway Regional Health Authority
| | - Mirta M L Sousa
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.,Clinic of Laboratory Medicine, St. Olav's Hospital, Trondheim University Hospital, NO-7006 Trondheim, Norway.,PROMEC Core Facility for Proteomics and Modomics at NTNU and the Central Norway Regional Health Authority
| | - Hans E Krokan
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway
| | - Bodil Kavli
- Department of Clinical and Molecular Medicine, NTNU-Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.,Clinic of Laboratory Medicine, St. Olav's Hospital, Trondheim University Hospital, NO-7006 Trondheim, Norway
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27
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Banerjee DR, Deckard CE, Zeng Y, Sczepanski JT. Acetylation of the histone H3 tail domain regulates base excision repair on higher-order chromatin structures. Sci Rep 2019; 9:15972. [PMID: 31685935 PMCID: PMC6828659 DOI: 10.1038/s41598-019-52340-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/15/2019] [Indexed: 02/07/2023] Open
Abstract
Despite recent evidence suggesting that histone lysine acetylation contributes to base excision repair (BER) in cells, their exact mechanistic role remains unclear. In order to examine the influence of histone acetylation on the initial steps of BER, we assembled nucleosome arrays consisting of homogeneously acetylated histone H3 (H3K18 and H3K27) and measured the repair of a site-specifically positioned 2′-deoxyuridine (dU) residue by uracil DNA glycosylase (UDG) and apurinic/apyrimidinic endonuclease 1 (APE1). We find that H3K18ac and H3K27ac differentially influence the combined activities of UDG/APE1 on compact chromatin, suggesting that acetylated lysine residues on the H3 tail domain play distinct roles in regulating the initial steps of BER. In addition, we show that the effects of H3 tail domain acetylation on UDG/APE1 activity are at the nucleosome level and do not influence higher-order chromatin folding. Overall, these results establish a novel regulatory role for histone H3 acetylation during the initiation of BER on chromatin.
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Affiliation(s)
- Deb Ranjan Banerjee
- Department of Chemistry, National Institute of Technology, Durgapur, West Bengal, India
| | - Charles E Deckard
- Department of Chemistry, Texas A&M University, College Station, Texas, 77843, United States
| | - Yu Zeng
- Department of Microbial Pathogenesis and Immunology, Texas A&M University, College Station, Texas, 77843, United States
| | - Jonathan T Sczepanski
- Department of Chemistry, Texas A&M University, College Station, Texas, 77843, United States.
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28
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Sakhtemani R, Senevirathne V, Stewart J, Perera MLW, Pique-Regi R, Lawrence MS, Bhagwat AS. Genome-wide mapping of regions preferentially targeted by the human DNA-cytosine deaminase APOBEC3A using uracil-DNA pulldown and sequencing. J Biol Chem 2019; 294:15037-15051. [PMID: 31431505 DOI: 10.1074/jbc.ra119.008053] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 08/13/2019] [Indexed: 12/16/2022] Open
Abstract
Activation-induced deaminase (AID) and apolipoprotein B mRNA-editing enzyme catalytic subunit (APOBEC) enzymes convert cytosines to uracils, creating signature mutations that have been used to predict sites targeted by these enzymes. Mutation-based targeting maps are distorted by the error-prone or error-free repair of these uracils and by selection pressures. To directly map uracils created by AID/APOBEC enzymes, here we used uracil-DNA glycosylase and an alkoxyamine to covalently tag and sequence uracil-containing DNA fragments (UPD-Seq). We applied this technique to the genome of repair-defective, APOBEC3A-expressing bacterial cells and created a uracilation genome map, i.e. uracilome. The peak uracilated regions were in the 5'-ends of genes and operons mainly containing tRNA genes and a few protein-coding genes. We validated these findings through deep sequencing of pulldown regions and whole-genome sequencing of independent clones. The peaks were not correlated with high transcription rates or stable RNA:DNA hybrid formation. We defined the uracilation index (UI) as the frequency of occurrence of TT in UPD-Seq reads at different original TC dinucleotides. Genome-wide UI calculation confirmed that APOBEC3A modifies cytosines in the lagging-strand template during replication and in short hairpin loops. APOBEC3A's preference for tRNA genes was observed previously in yeast, and an analysis of human tumor sequences revealed that in tumors with a high percentage of APOBEC3 signature mutations, the frequency of tRNA gene mutations was much higher than in the rest of the genome. These results identify multiple causes underlying selection of cytosines by APOBEC3A for deamination, and demonstrate the utility of UPD-Seq.
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Affiliation(s)
- Ramin Sakhtemani
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | | | - Jessica Stewart
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - Madusha L W Perera
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202
| | - Roger Pique-Regi
- Center for Molecular Medicine and Genetics, Wayne State University, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Michael S Lawrence
- Department of Pathology and Cancer Center, Massachusetts General Hospital, Boston, Massachusetts 02114
| | - Ashok S Bhagwat
- Department of Chemistry, Wayne State University, Detroit, Michigan 48202 .,Department of Biochemistry, Microbiology and Immunology, Wayne State University School of Medicine, Detroit, Michigan 48201
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29
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Liu ZJ, Martínez Cuesta S, van Delft P, Balasubramanian S. Sequencing abasic sites in DNA at single-nucleotide resolution. Nat Chem 2019; 11:629-637. [PMID: 31209299 PMCID: PMC6589398 DOI: 10.1038/s41557-019-0279-9] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 04/30/2019] [Indexed: 12/27/2022]
Abstract
In DNA, the loss of a nucleobase by hydrolysis generates an abasic site. Formed as a result of DNA damage, as well as a key intermediate during the base excision repair pathway, abasic sites are frequent DNA lesions that can lead to mutations and strand breaks. Here we present snAP-seq, a chemical approach that selectively exploits the reactive aldehyde moiety at abasic sites to reveal their location within DNA at single-nucleotide resolution. Importantly, the approach resolves abasic sites from other aldehyde functionalities known to exist in genomic DNA. snAP-seq was validated on synthetic DNA and then applied to two separate genomes. We studied the distribution of thymine modifications in the Leishmania major genome by enzymatically converting these modifications into abasic sites followed by abasic site mapping. We also applied snAP-seq directly to HeLa DNA to provide a map of endogenous abasic sites in the human genome.
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Affiliation(s)
- Zheng J Liu
- Department of Chemistry, University of Cambridge, Cambridge, UK
| | - Sergio Martínez Cuesta
- Department of Chemistry, University of Cambridge, Cambridge, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK
| | | | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge, UK.
- Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, UK.
- School of Clinical Medicine, University of Cambridge, Cambridge, UK.
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30
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Cui J, Gizzi A, Stivers JT. Deoxyuridine in DNA has an inhibitory and promutagenic effect on RNA transcription by diverse RNA polymerases. Nucleic Acids Res 2019; 47:4153-4168. [PMID: 30892639 PMCID: PMC6486633 DOI: 10.1093/nar/gkz183] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/04/2019] [Accepted: 03/09/2019] [Indexed: 12/16/2022] Open
Abstract
dUTP is a close structural congener of dTTP and can be readily incorporated into DNA opposite to adenine during DNA replication leading to non-mutagenic dU/A base pairs ('uracilation'). We find that dU/A pairs located within DNA transcriptional templates optimized for either T7 RNA polymerase (T7 RNAP) or human RNA polymerase II (pol II) have inhibitory and mutagenic effects on transcription. The data for T7 RNAP establishes that even a single dU/A pair can inhibit promoter binding and transcription initiation up to 30-fold, and that inhibitory effects on transcription elongation are also possible. Sequencing of the mRNA transcribed from uniformly uracilated DNA templates by T7 RNAP indicated an increased frequency of transversion and insertion mutations compared to all T/A templates. Strong effects of dU/A pairs on cellular transcription activity and fidelity were also observed with RNA pol II using uracil base excision repair (UBER)-deficient human cells. At the highest levels of template uracilation, transcription by RNA pol II was completely blocked. We propose that these effects arise from the decreased thermodynamic stability and increased dynamics of dU/A pairs in DNA. The potential implications of these findings on gene regulation and disease are discussed.
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Affiliation(s)
- Junru Cui
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
| | - Anthony Gizzi
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
| | - James T Stivers
- Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA
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31
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Hofer A, Liu ZJ, Balasubramanian S. Detection, Structure and Function of Modified DNA Bases. J Am Chem Soc 2019; 141:6420-6429. [DOI: 10.1021/jacs.9b01915] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Alexandre Hofer
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Zheng J. Liu
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
- Cancer Research
UK Cambridge Institute, University of Cambridge, Cambridge CB2 0RE, United Kingdom
- School of Clinical Medicine, University of Cambridge, Cambridge CB2 0SP, United Kingdom
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32
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Chon J, Field MS, Stover PJ. Deoxyuracil in DNA and disease: Genomic signal or managed situation? DNA Repair (Amst) 2019; 77:36-44. [PMID: 30875637 DOI: 10.1016/j.dnarep.2019.02.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 02/26/2019] [Indexed: 12/21/2022]
Abstract
Genomic instability is implicated in the etiology of several deleterious health outcomes including megaloblastic anemia, neural tube defects, and neurodegeneration. Uracil misincorporation and its repair are known to cause genomic instability by inducing DNA strand breaks leading to apoptosis, but there is emerging evidence that uracil incorporation may also result in broader modifications of gene expression, including: changes in transcriptional stalling, strand break-mediated transcriptional upregulation, and direct promoter inhibition. The factors that influence uracil levels in DNA are cytosine deamination, de novo thymidylate (dTMP) biosynthesis, salvage dTMP biosynthesis, dUTPase, and DNA repair. There is evidence that the nuclear localization of the enzymes in these pathways in mammalian cells may modify and/or control the levels of uracil accumulation into nuclear DNA. Uracil sequencing technologies demonstrate that uracil in DNA is not distributed stochastically across the genome, but instead shows patterns of enrichment. Nuclear localization of the enzymes that modify uracil in DNA may serve to change these patterns of enrichment in a tissue-specific manner, and thereby signal the genome in response to metabolic and/or nutritional state of the cell.
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Affiliation(s)
- James Chon
- Graduate Field of Biochemistry, Molecular and Cellular Biology, Cornell University, Ithaca, NY, 14853, USA
| | - Martha S Field
- Division of Nutritional Sciences, Cornell University, 127 Savage Hall, Ithaca, NY, 14853, USA
| | - Patrick J Stover
- Graduate Field of Biochemistry, Molecular and Cellular Biology, Cornell University, Ithaca, NY, 14853, USA; Division of Nutritional Sciences, Cornell University, 127 Savage Hall, Ithaca, NY, 14853, USA.
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33
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Papp-Kádár V, Balázs Z, Vékey K, Ozohanics O, Vértessy BG. Mass spectrometry-based analysis of macromolecular complexes of Staphylococcus aureus uracil-DNA glycosylase and its inhibitor reveals specific variations due to naturally occurring mutations. FEBS Open Bio 2019; 9:420-427. [PMID: 30868050 PMCID: PMC6396141 DOI: 10.1002/2211-5463.12567] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 08/10/2018] [Accepted: 09/06/2018] [Indexed: 12/13/2022] Open
Abstract
The base excision repair pathway plays an important role in correcting damage induced by either physiological or external effects. This repair pathway removes incorrect bases from the DNA. The uracil base is among the most frequently occurring erroneous bases in DNA, and is cut out from the phosphodiester backbone via the catalytic action of uracil‐DNA glycosylase. Uracil excision repair is an evolutionarily highly conserved pathway and can be specifically inhibited by a protein inhibitor of uracil‐DNA glycosylase. Interestingly, both uracil‐DNA glycosylase (Staphylococcus aureus uracil‐DNA glycosylase; SAUDG) and its inhibitor (S. aureus uracil‐DNA glycosylase inhibitor; SAUGI) are present in the staphylococcal cell. The interaction of these two proteins effectively decreases the efficiency of uracil‐DNA excision repair. The physiological relevance of this complexation has not yet been addressed in detailed; however, numerous mutations have been identified within SAUGI. Here, we investigated whether these mutations drastically perturb the interaction with SAUDG. To perform quantitative analysis of the macromolecular interactions, we applied native mass spectrometry and demonstrated that this is a highly efficient and specific method for determination of dissociation constants. Our results indicate that several naturally occurring mutations of SAUGI do indeed lead to appreciable changes in the dissociation constants for complex formation. However, all of these Kd values remain in the nanomolar range and therefore the association of these two proteins is preserved. We conclude that complexation is most likely preserved even with the naturally occurring mutant uracil‐DNA glycosylase inhibitor proteins.
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Affiliation(s)
- Veronika Papp-Kádár
- Hungarian Academy of Sciences Research Centre for Natural Sciences Institute of Enzymology Budapest Hungary.,Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
| | - Zoltán Balázs
- Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
| | - Károly Vékey
- Hungarian Academy of Sciences Research Centre for Natural Sciences Institute of Organic Chemistry Budapest Hungary
| | - Olivér Ozohanics
- Hungarian Academy of Sciences Research Centre for Natural Sciences Institute of Organic Chemistry Budapest Hungary.,Department of Medical Biochemistry Semmelweis University Budapest Hungary
| | - Beáta G Vértessy
- Hungarian Academy of Sciences Research Centre for Natural Sciences Institute of Enzymology Budapest Hungary.,Department of Applied Biotechnology and Food Science Budapest University of Technology and Economics Budapest Hungary
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34
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Lai W, Mo J, Yin J, Lyu C, Wang H. Profiling of epigenetic DNA modifications by advanced liquid chromatography-mass spectrometry technologies. Trends Analyt Chem 2019. [DOI: 10.1016/j.trac.2018.10.031] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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35
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Wang Y, Liu C, Wu F, Zhang X, Liu S, Chen Z, Zeng W, Yang W, Zhang X, Zhou Y, Weng X, Wu Z, Zhou X. Highly Selective 5-Formyluracil Labeling and Genome-wide Mapping Using (2-Benzimidazolyl)Acetonitrile Probe. iScience 2018; 9:423-432. [PMID: 30466066 PMCID: PMC6249349 DOI: 10.1016/j.isci.2018.10.024] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 09/04/2018] [Accepted: 10/23/2018] [Indexed: 02/08/2023] Open
Abstract
Chemical modifications to nucleobases have a great influence on various cellular processes, by making gene regulation more complex, thus indicating their profound impact on aspects of heredity, growth, and disease. Here, we provide the first genome-wide map of 5-formyluracil (5fU) in living tissues and evaluate the potential roles for 5fU in genomics. We show that an azido derivative of (2-benzimidazolyl)acetonitrile has high selectivity for enriching 5fU-containing genomic DNA. The results have demonstrated the feasibility of using this method to determine the genome-wide distribution of 5fU. Intriguingly, most 5fU sites were found in intergenic regions and introns. Also, distribution of 5fU in human thyroid carcinoma tissues is positively correlated with binding sites of POLR2A protein, which indicates that 5fU may distributed around POLR2A-binding sites. The derivative of (2-benzimidazolyl)acetonitrile (azi-BIAN) can selectivity label 5fU Azi-BIAN can selectively label and pull down 5fU in the genome for NGS The first genome-wide map of 5fU in mammalian genomic DNA 5fU is highly enriched at intergenic regions and introns
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Affiliation(s)
- Yafen Wang
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Chaoxing Liu
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Fan Wu
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Xiong Zhang
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Sheng Liu
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, School of Medicine, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Zonggui Chen
- College of Life Science, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Weiwu Zeng
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Wei Yang
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Xiaolian Zhang
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology and Department of Immunology, School of Medicine, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Yu Zhou
- College of Life Science, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Xiaocheng Weng
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Zhiguo Wu
- College of Life Science, Wuhan University, Wuhan, Hubei 430072, P. R. China
| | - Xiang Zhou
- College of Chemistry and Molecular Sciences, Key Laboratory of Biomedical Polymers of Ministry of Education, The Institute for Advanced Studies, Hubei Province Key Laboratory of Allergy and Immunology, Wuhan University, Wuhan, Hubei 430072, P. R. China.
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The etiology of uracil residues in the Saccharomyces cerevisiae genomic DNA. Curr Genet 2018; 65:393-399. [PMID: 30328489 PMCID: PMC6420880 DOI: 10.1007/s00294-018-0895-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 10/11/2018] [Accepted: 10/13/2018] [Indexed: 11/29/2022]
Abstract
Non-canonical residue in DNA is a major and conserved source of genome instability. The appearance of uracil residues in DNA accompanies a significant mutagenic consequence and is regulated at multiple levels, from the concentration of available dUTP in the nucleotide pool to the excision repair for removal from DNA. Recently, an interesting phenomenon of transcription-associated elevation in uracil-derived mutations was described in Saccharomyces cerevisiae genome. While trying to understand the variability in mutagenesis, we uncovered that the frequency of uracil incorporation into DNA can vary depending on the transcription rate and that the non-replicative, repair-associated DNA synthesis underlies the higher uracil density of the actively transcribed genomic loci. This novel mechanism brings together the chemical vulnerability of DNA under transcription and the uracil-associated mutagenesis, and has the potential to apply to other non-canonical residues of mutagenic importance.
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