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Neupane A, Chariker JH, Rouchka EC. Analysis of Nucleotide Variations in Human G-Quadruplex Forming Regions Associated with Disease States. Genes (Basel) 2023; 14:2125. [PMID: 38136947 PMCID: PMC10742762 DOI: 10.3390/genes14122125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/20/2023] [Accepted: 11/23/2023] [Indexed: 12/24/2023] Open
Abstract
While the role of G quadruplex (G4) structures has been identified in cancers and metabolic disorders, single nucleotide variations (SNVs) and their effect on G4s in disease contexts have not been extensively studied. The COSMIC and CLINVAR databases were used to detect SNVs present in G4s to identify sequence level changes and their effect on the alteration of the G4 secondary structure. A total of 37,515 G4 SNVs in the COSMIC database and 2378 in CLINVAR were identified. Of those, 7236 COSMIC (19.3%) and 457 (19%) of the CLINVAR variants result in G4 loss, while 2728 (COSMIC) and 129 (CLINVAR) SNVs gain a G4 structure. The remaining variants potentially affect the folding energy without affecting the presence of a G4. Analysis of mutational patterns in the G4 structure shows a higher selective pressure (3-fold) in the coding region on the template strand compared to the reverse strand. At the same time, an equal proportion of SNVs were observed among intronic, promoter, and enhancer regions across strands.
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Affiliation(s)
- Aryan Neupane
- School of Graduate and Interdisciplinary Studies, University of Louisville, Louisville, KY 40292, USA;
| | - Julia H. Chariker
- Department of Neuroscience Training, University of Louisville, Louisville, KY 40292, USA;
- Kentucky IDeA Network of Biomedical Research Excellence (KY INBRE) Bioinformatics Core, University of Louisville, Louisville, KY 40292, USA
| | - Eric C. Rouchka
- Kentucky IDeA Network of Biomedical Research Excellence (KY INBRE) Bioinformatics Core, University of Louisville, Louisville, KY 40292, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, KY 40292, USA
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2
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Malfatti MC, Bellina A, Antoniali G, Tell G. Revisiting Two Decades of Research Focused on Targeting APE1 for Cancer Therapy: The Pros and Cons. Cells 2023; 12:1895. [PMID: 37508559 PMCID: PMC10378182 DOI: 10.3390/cells12141895] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Revised: 07/06/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
APE1 is an essential endodeoxyribonuclease of the base excision repair pathway that maintains genome stability. It was identified as a pivotal factor favoring tumor progression and chemoresistance through the control of gene expression by a redox-based mechanism. APE1 is overexpressed and serum-secreted in different cancers, representing a prognostic and predictive factor and a promising non-invasive biomarker. Strategies directly targeting APE1 functions led to the identification of inhibitors showing potential therapeutic value, some of which are currently in clinical trials. Interestingly, evidence indicates novel roles of APE1 in RNA metabolism that are still not fully understood, including its activity in processing damaged RNA in chemoresistant phenotypes, regulating onco-miRNA maturation, and oxidized RNA decay. Recent data point out a control role for APE1 in the expression and sorting of onco-miRNAs within secreted extracellular vesicles. This review is focused on giving a portrait of the pros and cons of the last two decades of research aiming at the identification of inhibitors of the redox or DNA-repair functions of APE1 for the definition of novel targeted therapies for cancer. We will discuss the new perspectives in cancer therapy emerging from the unexpected finding of the APE1 role in miRNA processing for personalized therapy.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy
| | - Alessia Bellina
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy
| | - Giulia Antoniali
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, 33100 Udine, Italy
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3
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Malfatti MC, Antoniali G, Tell G. In Vitro Assay to Measure APE1 Enzymatic Activity on Ribose Monophosphate Abasic Site. Methods Mol Biol 2023; 2701:21-38. [PMID: 37574473 DOI: 10.1007/978-1-0716-3373-1_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
APE1 (apurinic/apyrimidinic endodeoxyribonuclease 1) is a central enzyme of the base excision repair (BER) pathway playing a pivotal role in protecting mammalian cells against genotoxins and in safeguarding genome stability. Recently, we demonstrated the APE1 ability to process abasic ribonucleotides embedded in DNA. Here, we provide a pipeline of protocols to quantify endodeoxyribonuclease activity by APE1 on these substrates, by using recombinant protein and whole-cell extracts. The repair capacity is measured by using fluorescent oligonucleotide substrates, which are then separated by polyacrylamide gel electrophoresis and detected by imaging scanning. The specificity of APE1 action is demonstrated using specific APE1 enzymatic inhibitors.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy
| | - Giulia Antoniali
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy.
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4
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Feng M, Luo J, Wan Y, Zhang J, Lu C, Wang M, Dai L, Cao X, Yang X, Wang Y. Polystyrene Nanoplastic Exposure Induces Developmental Toxicity by Activating the Oxidative Stress Response and Base Excision Repair Pathway in Zebrafish ( Danio rerio). ACS OMEGA 2022; 7:32153-32163. [PMID: 36119974 PMCID: PMC9476205 DOI: 10.1021/acsomega.2c03378] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/22/2022] [Indexed: 02/05/2023]
Abstract
The widespread accumulation of nanoplastics is a growing concern for the environmental and human health. However, studies on the mechanisms of nanoplastic-induced developmental toxicity are still limited. Here, we systematically investigated the potential biological roles of nanoplastic exposure in zebrafish during the early developmental stage. The zebrafish embryos were subjected to exposure to 100 nm polystyrene nanoplastics with different concentrations (0, 100, 200, and 400 mg/L). The results indicated that nanoplastic exposure could decrease the hatching and survival rates of zebrafish embryos. In addition, the developmental toxicity test indicated that nanoplastic exposure exhibits developmental toxicity via the inhibition of the heart rate and body length in zebrafish embryos. Besides, behavioral activity was also significantly suppressed after 96 h of nanoplastic exposure in zebrafish larvae. Further biochemical assays revealed that nanoplastic-induced activation of the oxidative stress responses, including reactive oxygen species accumulation and enhanced superoxide dismutase and catalase activities, might affect developmental toxicity in zebrafish embryos. Furthermore, a quantitative polymerase chain reaction assay demonstrated that the mRNA levels of the base excision repair (BER) pathway-related genes, including lig1, lig3, polb, parp1, pold, fen1, nthl1, apex, xrcc1, and ogg1, were altered in zebrafish embryos for 24 h after nanoplastic exposure, indicating that the activation of the BER pathway would be stimulated after nanoplastic exposure in zebrafish embryos. Therefore, our findings illustrated that nanoplastics could induce developmental toxicity through activation of the oxidative stress response and BER pathways in zebrafish.
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Affiliation(s)
- Meilan Feng
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Juanjuan Luo
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Yiping Wan
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Jiannan Zhang
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Chunjiao Lu
- Guangdong
Provincial Key Laboratory of Infectious Disease and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, China
| | - Maya Wang
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Lu Dai
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Xiaoqian Cao
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, China
| | - Xiaojun Yang
- Guangdong Provincial Key Laboratory of Infectious Disease and Molecular Immunopathology, Shantou University Medical College, Shantou 515041,China
| | - Yajun Wang
- Key Laboratory of Bio-resources and Eco-environment of Ministry of Education, College of Life Science, Sichuan University, Chengdu 610065, China
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5
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Torgasheva NA, Diatlova EA, Grin IR, Endutkin AV, Mechetin GV, Vokhtantsev IP, Yudkina AV, Zharkov DO. Noncatalytic Domains in DNA Glycosylases. Int J Mol Sci 2022; 23:ijms23137286. [PMID: 35806289 PMCID: PMC9266487 DOI: 10.3390/ijms23137286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 02/04/2023] Open
Abstract
Many proteins consist of two or more structural domains: separate parts that have a defined structure and function. For example, in enzymes, the catalytic activity is often localized in a core fragment, while other domains or disordered parts of the same protein participate in a number of regulatory processes. This situation is often observed in many DNA glycosylases, the proteins that remove damaged nucleobases thus initiating base excision DNA repair. This review covers the present knowledge about the functions and evolution of such noncatalytic parts in DNA glycosylases, mostly concerned with the human enzymes but also considering some unique members of this group coming from plants and prokaryotes.
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Affiliation(s)
- Natalia A. Torgasheva
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
| | - Evgeniia A. Diatlova
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Street, 630090 Novosibirsk, Russia
| | - Inga R. Grin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
| | - Anton V. Endutkin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
| | - Grigory V. Mechetin
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
| | - Ivan P. Vokhtantsev
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Street, 630090 Novosibirsk, Russia
| | - Anna V. Yudkina
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
| | - Dmitry O. Zharkov
- SB RAS Institute of Chemical Biology and Fundamental Medicine, 8 Lavrentieva Avenue, 630090 Novosibirsk, Russia; (N.A.T.); (E.A.D.); (I.R.G.); (A.V.E.); (G.V.M.); (I.P.V.); (A.V.Y.)
- Department of Natural Sciences, Novosibirsk State University, 2 Pirogova Street, 630090 Novosibirsk, Russia
- Correspondence:
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6
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Liang L, Mai S, Mai G, Chen Y, Liu L. DNA damage repair-related gene signature predicts prognosis and indicates immune cell infiltration landscape in skin cutaneous melanoma. Front Endocrinol (Lausanne) 2022; 13:882431. [PMID: 35957812 PMCID: PMC9361349 DOI: 10.3389/fendo.2022.882431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND DNA damage repair plays an important role in the onset and progression of cancers and its resistance to treatment therapy. This study aims to assess the prognostic potential of DNA damage repair markers in skin cutaneous melanoma (SKCM). METHOD In this study, we have analyzed the gene expression profiles being downloaded from TCGA, GTEx, and GEO databases. We sequentially used univariate and LASSO Cox regression analyses to screen DNA repair genes associated with prognosis. Then, we have conducted a multivariate regression analysis to construct the prognostic profile of DNA repair-related genes (DRRGs). The risk coefficient is used to calculate the risk scores and divide the patients into two cohorts. Additionally, we validated our prognosis model on an external cohort as well as evaluated the link between immune response and the DRRGs prognostic profiles. The risk signature is compared to immune cell infiltration, chemotherapy, and immune checkpoint inhibitors (ICIs) treatment. RESULTS An analysis using LASSO-Cox stepwise regression established a prognostic signature consisting of twelve DRRGs with strong predictive ability. Disease-specific survival (DSS) is found to be lower among high-risk patients group as compared to low-risk patients. The signature may be employed as an independent prognostic predictor after controlling for clinicopathological factors, as demonstrated by validation on one external GSE65904 cohort. A strong correlation is also found between the risk score and the immune microenvironment, along with the infiltrating immune cells, and ICIs key molecules. The gene enrichment analysis results indicate a wide range of biological activities and pathways to be exhibited by high-risk groups. Furthermore, Cisplatin exhibited a considerable response sensitivity in low-risk groups as opposed to the high-risk incidents, while docetaxel exhibited a considerable response sensitivity in high-risk groups. CONCLUSIONS Our findings provide a thorough investigation of DRRGs to develop an DSS-related prognostic indicator which may be useful in forecasting SKCM progression and enabling more enhanced clinical benefits from immunotherapy.
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Affiliation(s)
- Liping Liang
- Department of Gastroenterology, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Shijie Mai
- Department of Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Genghui Mai
- Department of Gastroenterology, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Ye Chen
- Department of Gastroenterology, State Key Laboratory of Organ Failure Research, Guangdong Provincial Key Laboratory of Gastroenterology, Nanfang Hospital, Southern Medical University, Guangzhou, China
- Department of Gastroenterology, Integrated Clinical Microecology Center, Shenzhen Hospital, Southern Medical University, Shenzhen, China
- *Correspondence: Le Liu, ; Ye Chen,
| | - Le Liu
- Department of Gastroenterology, Integrated Clinical Microecology Center, Shenzhen Hospital, Southern Medical University, Shenzhen, China
- *Correspondence: Le Liu, ; Ye Chen,
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7
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Hindi NN, Elsakrmy N, Ramotar D. The base excision repair process: comparison between higher and lower eukaryotes. Cell Mol Life Sci 2021; 78:7943-7965. [PMID: 34734296 PMCID: PMC11071731 DOI: 10.1007/s00018-021-03990-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 09/08/2021] [Accepted: 10/14/2021] [Indexed: 01/01/2023]
Abstract
The base excision repair (BER) pathway is essential for maintaining the stability of DNA in all organisms and defects in this process are associated with life-threatening diseases. It is involved in removing specific types of DNA lesions that are induced by both exogenous and endogenous genotoxic substances. BER is a multi-step mechanism that is often initiated by the removal of a damaged base leading to a genotoxic intermediate that is further processed before the reinsertion of the correct nucleotide and the restoration of the genome to a stable structure. Studies in human and yeast cells, as well as fruit fly and nematode worms, have played important roles in identifying the components of this conserved DNA repair pathway that maintains the integrity of the eukaryotic genome. This review will focus on the components of base excision repair, namely, the DNA glycosylases, the apurinic/apyrimidinic endonucleases, the DNA polymerase, and the ligases, as well as other protein cofactors. Functional insights into these conserved proteins will be provided from humans, Saccharomyces cerevisiae, Drosophila melanogaster, and Caenorhabditis elegans, and the implications of genetic polymorphisms and knockouts of the corresponding genes.
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Affiliation(s)
- Nagham Nafiz Hindi
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Noha Elsakrmy
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar
| | - Dindial Ramotar
- Division of Biological and Biomedical Sciences, College of Health and Life Sciences, Hamad Bin Khalifa University, Education City, Doha, Qatar.
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8
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Elbanna M, Chowdhury NN, Rhome R, Fishel ML. Clinical and Preclinical Outcomes of Combining Targeted Therapy With Radiotherapy. Front Oncol 2021; 11:749496. [PMID: 34733787 PMCID: PMC8558533 DOI: 10.3389/fonc.2021.749496] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/30/2021] [Indexed: 12/12/2022] Open
Abstract
In the era of precision medicine, radiation medicine is currently focused on the precise delivery of highly conformal radiation treatments. However, the tremendous developments in targeted therapy are yet to fulfill their full promise and arguably have the potential to dramatically enhance the radiation therapeutic ratio. The increased ability to molecularly profile tumors both at diagnosis and at relapse and the co-incident progress in the field of radiogenomics could potentially pave the way for a more personalized approach to radiation treatment in contrast to the current ‘‘one size fits all’’ paradigm. Few clinical trials to date have shown an improved clinical outcome when combining targeted agents with radiation therapy, however, most have failed to show benefit, which is arguably due to limited preclinical data. Several key molecular pathways could theoretically enhance therapeutic effect of radiation when rationally targeted either by directly enhancing tumor cell kill or indirectly through the abscopal effect of radiation when combined with novel immunotherapies. The timing of combining molecular targeted therapy with radiation is also important to determine and could greatly affect the outcome depending on which pathway is being inhibited.
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Affiliation(s)
- May Elbanna
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN, United States.,Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Nayela N Chowdhury
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Ryan Rhome
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN, United States.,Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Melissa L Fishel
- Indiana University Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN, United States.,Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN, United States.,Department of Pediatrics and Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, United States
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9
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Fleming AM, Burrows CJ. Oxidative stress-mediated epigenetic regulation by G-quadruplexes. NAR Cancer 2021; 3:zcab038. [PMID: 34541539 PMCID: PMC8445369 DOI: 10.1093/narcan/zcab038] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 08/20/2021] [Accepted: 09/06/2021] [Indexed: 02/06/2023] Open
Abstract
Many cancer-associated genes are regulated by guanine (G)-rich sequences that are capable of refolding from the canonical duplex structure to an intrastrand G-quadruplex. These same sequences are sensitive to oxidative damage that is repaired by the base excision repair glycosylases OGG1 and NEIL1–3. We describe studies indicating that oxidation of a guanosine base in a gene promoter G-quadruplex can lead to up- and downregulation of gene expression that is location dependent and involves the base excision repair pathway in which the first intermediate, an apurinic (AP) site, plays a key role mediated by AP endonuclease 1 (APE1/REF1). The nuclease activity of APE1 is paused at a G-quadruplex, while the REF1 capacity of this protein engages activating transcription factors such as HIF-1α, AP-1 and p53. The mechanism has been probed by in vitro biophysical studies, whole-genome approaches and reporter plasmids in cellulo. Replacement of promoter elements by a G-quadruplex sequence usually led to upregulation, but depending on the strand and precise location, examples of downregulation were also found. The impact of oxidative stress-mediated lesions in the G-rich sequence enhanced the effect, whether it was positive or negative.
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Affiliation(s)
- Aaron M Fleming
- Department of Chemistry, University of Utah, 315 S. 1400 East, Salt Lake City, UT 84112-0850, USA
| | - Cynthia J Burrows
- Department of Chemistry, University of Utah, 315 S. 1400 East, Salt Lake City, UT 84112-0850, USA
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10
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Kim DV, Kulishova LM, Torgasheva NA, Melentyev VS, Dianov GL, Medvedev SP, Zakian SM, Zharkov DO. Mild phenotype of knockouts of the major apurinic/apyrimidinic endonuclease APEX1 in a non-cancer human cell line. PLoS One 2021; 16:e0257473. [PMID: 34529719 PMCID: PMC8445474 DOI: 10.1371/journal.pone.0257473] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 09/01/2021] [Indexed: 12/26/2022] Open
Abstract
The major human apurinic/apyrimidinic (AP) site endonuclease, APEX1, is a central player in the base excision DNA repair (BER) pathway and has a role in the regulation of DNA binding by transcription factors. In vertebrates, APEX1 knockouts are embryonic lethal, and only a handful of knockout cell lines are known. To facilitate studies of multiple functions of this protein in human cells, we have used the CRISPR/Cas9 system to knock out the APEX1 gene in a widely used non-cancer hypotriploid HEK 293FT cell line. Two stable knockout lines were obtained, one carrying two single-base deletion alleles and one single-base insertion allele in exon 3, another homozygous in the single-base insertion allele. Both mutations cause a frameshift that leads to premature translation termination before the start of the protein's catalytic domain. Both cell lines totally lacked the APEX1 protein and AP site-cleaving activity, and showed significantly lower levels of the APEX1 transcript. The APEX1-null cells were unable to support BER on uracil- or AP site-containing substrates. Phenotypically, they showed a moderately increased sensitivity to methyl methanesulfonate (MMS; ~2-fold lower EC50 compared with wild-type cells), and their background level of natural AP sites detected by the aldehyde-reactive probe was elevated ~1.5-2-fold. However, the knockout lines retained a nearly wild-type sensitivity to oxidizing agents hydrogen peroxide and potassium bromate. Interestingly, despite the increased MMS cytotoxicity, we observed no additional increase in AP sites in knockout cells upon MMS treatment, which could indicate their conversion into more toxic products in the absence of repair. Overall, the relatively mild cell phenotype in the absence of APEX1-dependent BER suggests that mammalian cells possess mechanisms of tolerance or alternative repair of AP sites. The knockout derivatives of the extensively characterized HEK 293FT cell line may provide a valuable tool for studies of APEX1 in DNA repair and beyond.
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Affiliation(s)
- Daria V. Kim
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | - Liliya M. Kulishova
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
| | | | - Vasily S. Melentyev
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Cytology and Genetics, Novosibirsk, Russia
| | - Grigory L. Dianov
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Cytology and Genetics, Novosibirsk, Russia
- Department of Oncology, MRC Oxford Institute for Radiation Oncology, University of Oxford, Oxford, United Kingdom
| | | | - Suren M. Zakian
- SB RAS Institute of Cytology and Genetics, Novosibirsk, Russia
| | - Dmitry O. Zharkov
- Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
- SB RAS Institute of Chemical Biology and Fundamental Medicine, Novosibirsk, Russia
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11
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Integrated multi-omics analyses on patient-derived CRC organoids highlight altered molecular pathways in colorectal cancer progression involving PTEN. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:198. [PMID: 34154611 PMCID: PMC8215814 DOI: 10.1186/s13046-021-01986-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 05/16/2021] [Indexed: 12/23/2022]
Abstract
Background Colorectal cancer (CRC) represents the fourth leading cause of cancer-related deaths. The heterogeneity of CRC identity limits the usage of cell lines to study this type of tumor because of the limited representation of multiple features of the original malignancy. Patient-derived colon organoids (PDCOs) are a promising 3D-cell model to study tumor identity for personalized medicine, although this approach still lacks detailed characterization regarding molecular stability during culturing conditions. Correlation analysis that considers genomic, transcriptomic, and proteomic data, as well as thawing, timing, and culturing conditions, is missing. Methods Through integrated multi–omics strategies, we characterized PDCOs under different growing and timing conditions, to define their ability to recapitulate the original tumor. Results Whole Exome Sequencing allowed detecting temporal acquisition of somatic variants, in a patient-specific manner, having deleterious effects on driver genes CRC-associated. Moreover, the targeted NGS approach confirmed that organoids faithfully recapitulated patients’ tumor tissue. Using RNA-seq experiments, we identified 5125 differentially expressed transcripts in tumor versus normal organoids at different time points, in which the PTEN pathway resulted of particular interest, as also confirmed by further phospho-proteomics analysis. Interestingly, we identified the PTEN c.806_817dup (NM_000314) mutation, which has never been reported previously and is predicted to be deleterious according to the American College of Medical Genetics and Genomics (ACMG) classification. Conclusion The crosstalk of genomic, transcriptomic and phosphoproteomic data allowed to observe that PDCOs recapitulate, at the molecular level, the tumor of origin, accumulating mutations over time that potentially mimic the evolution of the patient’s tumor, underlining relevant potentialities of this 3D model. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-021-01986-8.
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12
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Malfatti MC, Antoniali G, Codrich M, Tell G. Coping with RNA damage with a focus on APE1, a BER enzyme at the crossroad between DNA damage repair and RNA processing/decay. DNA Repair (Amst) 2021; 104:103133. [PMID: 34049077 DOI: 10.1016/j.dnarep.2021.103133] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/06/2021] [Accepted: 05/09/2021] [Indexed: 12/17/2022]
Abstract
Interest in RNA damage as a novel threat associated with several human pathologies is rapidly increasing. Knowledge on damaged RNA recognition, repair, processing and decay is still scanty. Interestingly, in the last few years, more and more evidence put a bridge between DNA damage repair enzymes and the RNA world. The Apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1) was firstly identified as a crucial enzyme of the base excision repair (BER) pathway preserving genome stability toward non-distorting DNA lesion-induced damages. Later, an unsuspected role of APE1 in controlling gene expression was discovered and its pivotal involvement in several human pathologies, ranging from tumor progression to neurodegenerative diseases, has emerged. Recent novel findings indicate a role of APE1 in RNA metabolism, particularly in processing activities of damaged (abasic and oxidized) RNA and in the regulation of oncogenic microRNAs (miRNAs). Even though the role of miRNAs in human pathologies is well-known, the mechanisms underlying their quality control are still totally unexplored. A detailed knowledge of damaged RNA decay processes in human cells is crucial in order to understand the molecular processes involved in multiple pathologies. This cutting-edge perspective article will highlight these emerging aspects of damaged RNA processing and decay, focusing the attention on the involvement of APE1 in RNA world.
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Affiliation(s)
- Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Giulia Antoniali
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Marta Codrich
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA Repair, Department of Medicine, University of Udine, Piazzale M. Kolbe 4, 33100 Udine, Italy.
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Eshraghi M, Adlimoghaddam A, Mahmoodzadeh A, Sharifzad F, Yasavoli-Sharahi H, Lorzadeh S, Albensi BC, Ghavami S. Alzheimer's Disease Pathogenesis: Role of Autophagy and Mitophagy Focusing in Microglia. Int J Mol Sci 2021; 22:3330. [PMID: 33805142 PMCID: PMC8036323 DOI: 10.3390/ijms22073330] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/14/2021] [Accepted: 03/19/2021] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's disease (AD) is a debilitating neurological disorder, and currently, there is no cure for it. Several pathologic alterations have been described in the brain of AD patients, but the ultimate causative mechanisms of AD are still elusive. The classic hallmarks of AD, including amyloid plaques (Aβ) and tau tangles (tau), are the most studied features of AD. Unfortunately, all the efforts targeting these pathologies have failed to show the desired efficacy in AD patients so far. Neuroinflammation and impaired autophagy are two other main known pathologies in AD. It has been reported that these pathologies exist in AD brain long before the emergence of any clinical manifestation of AD. Microglia are the main inflammatory cells in the brain and are considered by many researchers as the next hope for finding a viable therapeutic target in AD. Interestingly, it appears that the autophagy and mitophagy are also changed in these cells in AD. Inside the cells, autophagy and inflammation interact in a bidirectional manner. In the current review, we briefly discussed an overview on autophagy and mitophagy in AD and then provided a comprehensive discussion on the role of these pathways in microglia and their involvement in AD pathogenesis.
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Affiliation(s)
- Mehdi Eshraghi
- Center for Motor Neuron Biology and Disease, Columbia University, New York, NY 10032, USA;
- Department of Pathology and Cell Biology, Columbia University, New York, NY 10032, USA
| | - Aida Adlimoghaddam
- St. Boniface Hospital Albrechtsen Research Centre, Division of Neurodegenerative Disorders, Winnipeg, MB R2H2A6, Canada; (A.A.); (B.C.A.)
| | - Amir Mahmoodzadeh
- Medical Biology Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah 6734667149, Iran;
| | - Farzaneh Sharifzad
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; (F.S.); (H.Y.-S.)
| | - Hamed Yasavoli-Sharahi
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; (F.S.); (H.Y.-S.)
| | - Shahrokh Lorzadeh
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
| | - Benedict C. Albensi
- St. Boniface Hospital Albrechtsen Research Centre, Division of Neurodegenerative Disorders, Winnipeg, MB R2H2A6, Canada; (A.A.); (B.C.A.)
- Department of Pharmacology & Therapeutics, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Saeid Ghavami
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
- Research Institute of Oncology and Hematology, Cancer Care Manitoba-University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Biology of Breathing Theme, Children Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
- Faculty of Medicine, Katowice School of Technology, 40-555 Katowice, Poland
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Mangiapane G, Parolini I, Conte K, Malfatti MC, Corsi J, Sanchez M, Pietrantoni A, D'Agostino VG, Tell G. Enzymatically active apurinic/apyrimidinic endodeoxyribonuclease 1 is released by mammalian cells through exosomes. J Biol Chem 2021; 296:100569. [PMID: 33753167 PMCID: PMC8080531 DOI: 10.1016/j.jbc.2021.100569] [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: 10/16/2020] [Revised: 03/11/2021] [Accepted: 03/18/2021] [Indexed: 12/11/2022] Open
Abstract
The apurinic/apyrimidinic endodeoxyribonuclease 1 (APE1), the main AP-endonuclease of the DNA base excision repair pathway, is a key molecule of interest to researchers due to its unsuspected roles in different nonrepair activities, such as: i) adaptive cell response to genotoxic stress, ii) regulation of gene expression, and iii) processing of microRNAs, which make it an excellent drug target for cancer treatment. We and others recently demonstrated that APE1 can be secreted in the extracellular environment and that serum APE1 may represent a novel prognostic biomarker in hepatocellular and non-small-cell lung cancers. However, the mechanism by which APE1 is released extracellularly was not described before. Here, using three different approaches for exosomes isolation: commercial kit, nickel-based isolation, and ultracentrifugation methods and various mammalian cell lines, we elucidated the mechanisms responsible for APE1 secretion. We demonstrated that APE1 p37 and p33 forms are actively secreted through extracellular vesicles (EVs), including exosomes from different mammalian cell lines. We then observed that APE1 p33 form is generated by proteasomal-mediated degradation and is enzymatically active in EVs. Finally, we revealed that the p33 form of APE1 accumulates in EVs upon genotoxic treatment by cisplatin and doxorubicin, compounds commonly found in chemotherapy pharmacological treatments. Taken together, these findings provide for the first time evidence that a functional Base Excision Repair protein is delivered through exosomes in response to genotoxic stresses, shedding new light into the complex noncanonical biological functions of APE1 and opening new intriguing perspectives on its role in cancer biology.
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Affiliation(s)
- Giovanna Mangiapane
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy
| | - Isabella Parolini
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Rome, Italy
| | - Kristel Conte
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy
| | - Matilde Clarissa Malfatti
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy
| | - Jessica Corsi
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Trento, Italy
| | | | | | - Vito G D'Agostino
- Department of Cellular, Computational and Integrative Biology (CIBIO), University of Trento, Trento, Italy
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA repair, Department of Medicine (DAME), University of Udine, Udine, Italy.
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15
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Nelson BC, Dizdaroglu M. Implications of DNA damage and DNA repair on human diseases. Mutagenesis 2021; 35:1-3. [PMID: 32052057 DOI: 10.1093/mutage/gez048] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Indexed: 12/14/2022] Open
Affiliation(s)
- Bryant C Nelson
- National Institute of Standards and Technology, Material Measurement Laboratory, Gaithersburg, MD, USA
| | - Miral Dizdaroglu
- National Institute of Standards and Technology, Material Measurement Laboratory, Gaithersburg, MD, USA
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16
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Lu C, Luo J, Liu Y, Yang X. The oxidative stress responses caused by phthalate acid esters increases mRNA abundance of base excision repair (BER) genes in vivo and in vitro. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111525. [PMID: 33120273 DOI: 10.1016/j.ecoenv.2020.111525] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 10/09/2020] [Accepted: 10/14/2020] [Indexed: 02/05/2023]
Abstract
The base excision repair (BER) pathway is an important defense response to oxidative DNA damage. It is known that exposures to phthalate esters (PAEs), including Dibutyl phthalate (DBP), Mono-(2-ethylhexyl) phthalate (MEHP), and Di-(2-ethylhexyl) phthalate (DEHP), cause reactive oxygen species-induced DNA damage and oxidative stress. Here, we determined the mRNA levels of BER pathway-related genes (ogg1, nthl1, apex1, parp1, xrcc1, lig3, ung, pcna, polb, pold, fen1, and lig1), pro-apoptotic gene (bax), and apoptotic suppressor gene (bcl2) in different PAEs-exposed zebrafish larvae and HEK293T cells. Further investigations were performed to examine reactive oxygen species (ROS) accumulation, superoxide dismutase (SOD) activity, developmental toxicity, and cell viability after PAEs exposure in vivo and in vitro. The results showed that PAEs exposure can induce developmental abnormalities in zebrafish larvae, and inhibit cell viability in HEK293T cells. Additionally, we found that PAEs exposure results in the accumulation of ROS and the inhibition of SOD activation in vivo and in vitro. Notably, the mRNA levels of BER pathway-related genes (OGG1, NTHL1, APEX1, XRCC1, UNG, POLB, POLD, FEN1) were significantly upregulated after DBP or MEHP exposure, whereas the mRNA levels of NTHL1, UNG, POLB, POLD, and FEN1 were significantly altered in DEHP-treated HEK293T cells. In zebrafish, the mRNA levels of ogg1, pcna, fen1 and lig1 genes were increased after DBP or DEHP exposure, whereas the mRNA levels of nthl1, apex1, parp1, lig3, pcna and polb were decreased after MEHP exposure, respectively. Thus, our findings indicated that PAEs exposure can induce developmental toxicity, cytotoxicity, and oxidative stress, as well as activate BER pathway in vivo and in vitro, suggesting that BER pathway might play critical roles in PAEs-induced oxidative stress through repairing oxidative DNA damage.
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Affiliation(s)
- Chunjiao Lu
- Shantou University Medical College, Shantou 515041, China
| | - Juanjuan Luo
- Shantou University Medical College, Shantou 515041, China
| | - Yao Liu
- Shantou University Medical College, Shantou 515041, China
| | - Xiaojun Yang
- Shantou University Medical College, Shantou 515041, China.
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17
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Vågbø CB, Slupphaug G. RNA in DNA repair. DNA Repair (Amst) 2020; 95:102927. [DOI: 10.1016/j.dnarep.2020.102927] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/22/2022]
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18
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Stratigopoulou M, van Dam TP, Guikema JEJ. Base Excision Repair in the Immune System: Small DNA Lesions With Big Consequences. Front Immunol 2020; 11:1084. [PMID: 32547565 PMCID: PMC7272602 DOI: 10.3389/fimmu.2020.01084] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/05/2020] [Indexed: 12/13/2022] Open
Abstract
The integrity of the genome is under constant threat of environmental and endogenous agents that cause DNA damage. Endogenous damage is particularly pervasive, occurring at an estimated rate of 10,000–30,000 per cell/per day, and mostly involves chemical DNA base lesions caused by oxidation, depurination, alkylation, and deamination. The base excision repair (BER) pathway is primary responsible for removing and repairing these small base lesions that would otherwise lead to mutations or DNA breaks during replication. Next to preventing DNA mutations and damage, the BER pathway is also involved in mutagenic processes in B cells during immunoglobulin (Ig) class switch recombination (CSR) and somatic hypermutation (SHM), which are instigated by uracil (U) lesions derived from activation-induced cytidine deaminase (AID) activity. BER is required for the processing of AID-induced lesions into DNA double strand breaks (DSB) that are required for CSR, and is of pivotal importance for determining the mutagenic outcome of uracil lesions during SHM. Although uracils are generally efficiently repaired by error-free BER, this process is surprisingly error-prone at the Ig loci in proliferating B cells. Breakdown of this high-fidelity process outside of the Ig loci has been linked to mutations observed in B-cell tumors and DNA breaks and chromosomal translocations in activated B cells. Next to its role in preventing cancer, BER has also been implicated in immune tolerance. Several defects in BER components have been associated with autoimmune diseases, and animal models have shown that BER defects can cause autoimmunity in a B-cell intrinsic and extrinsic fashion. In this review we discuss the contribution of BER to genomic integrity in the context of immune receptor diversification, cancer and autoimmune diseases.
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Affiliation(s)
- Maria Stratigopoulou
- Department of Pathology, Lymphoma and Myeloma Center Amsterdam (LYMMCARE), Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Tijmen P van Dam
- Department of Pathology, Lymphoma and Myeloma Center Amsterdam (LYMMCARE), Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Jeroen E J Guikema
- Department of Pathology, Lymphoma and Myeloma Center Amsterdam (LYMMCARE), Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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Moor N, Vasil’eva I, Lavrik O. Functional Role of N-Terminal Extension of Human AP Endonuclease 1 In Coordination of Base Excision DNA Repair via Protein-Protein Interactions. Int J Mol Sci 2020; 21:ijms21093122. [PMID: 32354179 PMCID: PMC7247576 DOI: 10.3390/ijms21093122] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 02/06/2023] Open
Abstract
Human apurinic/apyrimidinic endonuclease 1 (APE1) has multiple functions in base excision DNA repair (BER) and other cellular processes. Its eukaryote-specific N-terminal extension plays diverse regulatory roles in interaction with different partners. Here, we explored its involvement in interaction with canonical BER proteins. Using fluorescence based-techniques, we compared binding affinities of the full-length and N-terminally truncated forms of APE1 (APE1NΔ35 and APE1NΔ61) for functionally and structurally different DNA polymerase β (Polβ), X-ray repair cross-complementing protein 1 (XRCC1), and poly(adenosine diphosphate (ADP)-ribose) polymerase 1 (PARP1), in the absence and presence of model DNA intermediates. Influence of the N-terminal truncation on binding the AP site-containing DNA was additionally explored. These data suggest that the interaction domain for proteins is basically formed by the conserved catalytic core of APE1. The N-terminal extension being capable of dynamically interacting with the protein and DNA partners is mostly responsible for DNA-dependent modulation of protein–protein interactions. Polβ, XRCC1, and PARP1 were shown to more efficiently regulate the endonuclease activity of the full-length protein than that of APE1NΔ61, further suggesting contribution of the N-terminal extension to BER coordination. Our results advance the understanding of functional roles of eukaryote-specific protein extensions in highly coordinated BER processes.
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Affiliation(s)
- Nina Moor
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (N.M.); (I.V.)
| | - Inna Vasil’eva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (N.M.); (I.V.)
| | - Olga Lavrik
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, 630090 Novosibirsk, Russia; (N.M.); (I.V.)
- Novosibirsk State University, 630090 Novosibirsk, Russia
- Correspondence:
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