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Regulation of limited N-terminal proteolysis of APE1 in tumor via acetylation and its role in cell proliferation. Oncotarget 2017; 7:22590-604. [PMID: 26981776 PMCID: PMC5008384 DOI: 10.18632/oncotarget.8026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 11/25/2022] Open
Abstract
Mammalian apurinic/apyrimidinic (AP) endonuclease 1 (APE1), a ubiquitous and multifunctional protein, plays an essential role in the repair of both endogenous and drug-induced DNA damages in the genome. Unlike its E.coli counterpart Xth, mammalian APE1 has a unique N-terminal domain and possesses both DNA damage repair and transcriptional regulatory functions. Although the overexpression of APE1 in diverse cancer types and the association of APE1 expression with chemotherapy resistance and poor prognosis are well documented, the cellular and molecular mechanisms that alter APE1 functions during tumorigenesis are largely unknown. Here, we show the presence of full-length APE1 and N-terminal truncated isoforms of APE1 in tumor tissue samples of various cancer types. However, primary tumor tissue has higher levels of acetylated APE1 (AcAPE1) as well as full-length APE1 compared to adjacent non-tumor tissue. We found that APE1 is proteolytically cleaved by an unknown serine protease at its N-terminus following residue lysine (Lys) Lys6 and/or Lys7 and after Lys27 and Lys31 or Lys32. Acetylation of these Lys residues in APE1 prevents this proteolysis. The N-terminal domain of APE1 and its acetylation are required for modulation of the expression of hundreds of genes. Importantly, we found that AcAPE1 is essential for sustained cell proliferation. Together, our study demonstrates that increased acetylation levels of APE1 in tumor cells inhibit the limited N-terminal proteolysis of APE1 and thereby maintain the functions of APE1 to promote tumor cells' sustained proliferation and survival.
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52
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Antoniali G, Serra F, Lirussi L, Tanaka M, D'Ambrosio C, Zhang S, Radovic S, Dalla E, Ciani Y, Scaloni A, Li M, Piazza S, Tell G. Mammalian APE1 controls miRNA processing and its interactome is linked to cancer RNA metabolism. Nat Commun 2017; 8:797. [PMID: 28986522 PMCID: PMC5630600 DOI: 10.1038/s41467-017-00842-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 07/28/2017] [Indexed: 01/31/2023] Open
Abstract
Mammalian apurinic/apyrimidinic endonuclease 1 is a DNA repair enzyme involved in genome stability and expression of genes involved in oxidative stress responses, tumor progression and chemoresistance. However, the molecular mechanisms underlying the role of apurinic/apyrimidinic endonuclease 1 in these processes are still unclear. Recent findings point to a novel role of apurinic/apyrimidinic endonuclease 1 in RNA metabolism. Through the characterization of the interactomes of apurinic/apyrimidinic endonuclease 1 with RNA and other proteins, we demonstrate here a role for apurinic/apyrimidinic endonuclease 1 in pri-miRNA processing and stability via association with the DROSHA-processing complex during genotoxic stress. We also show that endonuclease activity of apurinic/apyrimidinic endonuclease 1 is required for the processing of miR-221/222 in regulating expression of the tumor suppressor PTEN. Analysis of a cohort of different cancers supports the relevance of our findings for tumor biology. We also show that apurinic/apyrimidinic endonuclease 1 participates in RNA-interactomes and protein-interactomes involved in cancer development, thus indicating an unsuspected post-transcriptional effect on cancer genes. APE1 plays an important role in the cellular response to oxidative stress, and mutations are linked to tumor progression and chemoresistance. Here, the authors characterize the interactions of APE1 with RNA and demonstrate a role in microRNA processing.
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Affiliation(s)
- Giulia Antoniali
- Department of Medicine, Laboratory of Molecular Biology and DNA repair, University of Udine, p.le M. Kolbe 4, Udine, 33100, Italy
| | - Fabrizio Serra
- Department of Medicine, Laboratory of Molecular Biology and DNA repair, University of Udine, p.le M. Kolbe 4, Udine, 33100, Italy.,Clinical and Experimental Onco-Hematology Unit, Centro di Riferimento Oncologico, I.R.C.C.S., via Franco Gallini 2, Aviano (PN), 33081, Italy
| | - Lisa Lirussi
- Department of Medicine, Laboratory of Molecular Biology and DNA repair, University of Udine, p.le M. Kolbe 4, Udine, 33100, Italy.,Department of Clinical Molecular Biology, University of Oslo and Akershus University Hospital, Sykehusveien 27, Nordbyhagen, 1474, Norway
| | - Mikiei Tanaka
- Laboratory of Biochemistry, National Heart Lung and Blood Institute, National Institutes of Health, 50 South Drive, MSC-8012, Bethesda, MD, 20892-8012, USA
| | - Chiara D'Ambrosio
- Proteomics and Mass Spectrometry Laboratory, Institute for the Animal Production System in the Mediterranean Environment (ISPAAM) National Research Council (CNR) of Italy, via Argine 1085, Naples, 80147, Italy
| | - Shiheng Zhang
- Cancer Center of Daping Hospital, Third Military Medical University, Chongqing, 400042, China
| | | | - Emiliano Dalla
- Laboratorio Nazionale CIB, Area Science Park Padriciano, Trieste, 34149, Italy
| | - Yari Ciani
- Laboratorio Nazionale CIB, Area Science Park Padriciano, Trieste, 34149, Italy
| | - Andrea Scaloni
- Proteomics and Mass Spectrometry Laboratory, Institute for the Animal Production System in the Mediterranean Environment (ISPAAM) National Research Council (CNR) of Italy, via Argine 1085, Naples, 80147, Italy
| | - Mengxia Li
- Cancer Center of Daping Hospital, Third Military Medical University, Chongqing, 400042, China.
| | - Silvano Piazza
- Laboratorio Nazionale CIB, Area Science Park Padriciano, Trieste, 34149, Italy. .,Bioinformatics Core Facility, Centre for Integrative Biology, CIBIO, University of Trento, via Sommarive 18, Povo, Trento, TN, 38123, Italy.
| | - Gianluca Tell
- Department of Medicine, Laboratory of Molecular Biology and DNA repair, University of Udine, p.le M. Kolbe 4, Udine, 33100, Italy.
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53
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DNA repair enzyme APE1 from evolutionarily ancient Hydra reveals redox activity exclusively found in mammalian APE1. DNA Repair (Amst) 2017; 59:44-56. [PMID: 28946035 DOI: 10.1016/j.dnarep.2017.09.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/10/2017] [Accepted: 09/15/2017] [Indexed: 01/12/2023]
Abstract
Only mammalian apurinic/apyrimidinic endonuclease1 (APE1) has been reported to possess both DNA repair and redox activities. C terminal of the protein is required for base excision repair, while the redox activity resides in the N terminal due to cysteine residues at specific positions. APE1s from other organisms studied so far lack the redox activity in spite of having the N terminal domain. We find that APE1 from the Cnidarian Hydra exhibits both endonuclease and redox activities similar to mammalian APE1. We further show the presence of the three indispensable cysteines in Hydra APE1 for redox activity by site directed mutagenesis. Importance of redox domain but not the repair domain of APE1 in regeneration has been demonstrated by using domain-specific inhibitors. Our findings clearly demonstrate that the redox function of APE1 evolved very early in metazoan evolution and is not a recent acquisition in mammalian APE1 as believed so far.
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54
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Limpose KL, Corbett AH, Doetsch PW. BERing the burden of damage: Pathway crosstalk and posttranslational modification of base excision repair proteins regulate DNA damage management. DNA Repair (Amst) 2017. [PMID: 28629773 DOI: 10.1016/j.dnarep.2017.06.007] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
DNA base damage and non-coding apurinic/apyrimidinic (AP) sites are ubiquitous types of damage that must be efficiently repaired to prevent mutations. These damages can occur in both the nuclear and mitochondrial genomes. Base excision repair (BER) is the frontline pathway for identifying and excising damaged DNA bases in both of these cellular compartments. Recent advances demonstrate that BER does not operate as an isolated pathway but rather dynamically interacts with components of other DNA repair pathways to modulate and coordinate BER functions. We define the coordination and interaction between DNA repair pathways as pathway crosstalk. Numerous BER proteins are modified and regulated by post-translational modifications (PTMs), and PTMs could influence pathway crosstalk. Here, we present recent advances on BER/DNA repair pathway crosstalk describing specific examples and also highlight regulation of BER components through PTMs. We have organized and reported functional interactions and documented PTMs for BER proteins into a consolidated summary table. We further propose the concept of DNA repair hubs that coordinate DNA repair pathway crosstalk to identify central protein targets that could play a role in designing future drug targets.
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Affiliation(s)
- Kristin L Limpose
- Graduate Program in Cancer Biology, Emory University, Atlanta, GA, 30322, United States
| | - Anita H Corbett
- Department of Biology, Emory University, Atlanta, GA, 30322, United States; Winship Cancer Institute, Emory University, Atlanta, GA 30322, United States.
| | - Paul W Doetsch
- Graduate Program in Cancer Biology, Emory University, Atlanta, GA, 30322, United States; Department of Radiation Oncology, Emory University School of Medicine, Atlanta, GA, 30322, United States; Winship Cancer Institute, Emory University, Atlanta, GA 30322, United States; Department of Biochemistry, Emory University, Atlanta, GA, 30322, United States.
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55
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Liang W, Wei X, Li Q, Dai N, Li CY, Deng Y, Jiang X, Tan XR, Dai XY, Li MX, Xu CX, Wang D, Zhong ZY. MicroRNA-765 Enhances the Anti-Angiogenic Effect of CDDP via APE1 in Osteosarcoma. J Cancer 2017; 8:1542-1551. [PMID: 28775773 PMCID: PMC5535709 DOI: 10.7150/jca.18680] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 02/26/2017] [Indexed: 12/22/2022] Open
Abstract
Human osteosarcoma (HOS) is the most common malignancy in children and adolescents and has a heterogeneous presentation and high mortality. Previous studies have shown that microRNAs contribute to RNA silencing and post-transcriptional regulation of gene expression. Here, we showed that significantly increased expression of miR-765 with or without CDDP (Cisplatin) down-regulates APE1 expression and angiogenesis-related markers (VEGF, FGF2, TGFβ, and CD34). Further investigation showed that miR-765 modulates osteosarcoma cell migration and angiogenesis following treatment with cisplatin in vitro and in vivo. MiR-765 increases the anti-angiogenic effect of CDDP in human osteosarcoma. Elucidation of the mechanism of the miR-765-APE1 axis in tumor progression of HOS will be beneficial in identifying biomarkers and therapeutic target of osteosarcoma.
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Affiliation(s)
- Wei Liang
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Xi Wei
- Department of Diagnostic and Therapeutic Ultrasonography, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key laboratory of Cancer Prevention and Therapy, Tianjin, China
| | - Qing Li
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Nan Dai
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Chong-Yi Li
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Yi Deng
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Xuan Jiang
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Xiao-Rong Tan
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Xiao-Yan Dai
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Meng-Xia Li
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Cheng-Xiong Xu
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Dong Wang
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
| | - Zhao-Yang Zhong
- Cancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing,400042, China
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56
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Human Apurinic/Apyrimidinic Endonuclease (APE1) Is Acetylated at DNA Damage Sites in Chromatin, and Acetylation Modulates Its DNA Repair Activity. Mol Cell Biol 2017; 37:MCB.00401-16. [PMID: 27994014 PMCID: PMC5335514 DOI: 10.1128/mcb.00401-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 12/14/2016] [Indexed: 11/20/2022] Open
Abstract
Apurinic/apyrimidinic (AP) sites, the most frequently formed DNA lesions in the genome, inhibit transcription and block replication. The primary enzyme that repairs AP sites in mammalian cells is the AP endonuclease (APE1), which functions through the base excision repair (BER) pathway. Although the mechanism by which APE1 repairs AP sites in vitro has been extensively investigated, it is largely unknown how APE1 repairs AP sites in cells. Here, we show that APE1 is acetylated (AcAPE1) after binding to the AP sites in chromatin and that AcAPE1 is exclusively present on chromatin throughout the cell cycle. Positive charges of acetylable lysine residues in the N-terminal domain of APE1 are essential for chromatin association. Acetylation-mediated neutralization of the positive charges of the lysine residues in the N-terminal domain of APE1 induces a conformational change; this in turn enhances the AP endonuclease activity of APE1. In the absence of APE1 acetylation, cells accumulated AP sites in the genome and showed higher sensitivity to DNA-damaging agents. Thus, mammalian cells, unlike Saccharomyces cerevisiae or Escherichia coli cells, require acetylation of APE1 for the efficient repair of AP sites and base damage in the genome. Our study reveals that APE1 acetylation is an integral part of the BER pathway for maintaining genomic integrity.
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57
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Ogawa LM, Baserga SJ. Crosstalk between the nucleolus and the DNA damage response. MOLECULAR BIOSYSTEMS 2017; 13:443-455. [PMID: 28112326 PMCID: PMC5340083 DOI: 10.1039/c6mb00740f] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Nucleolar function and the cellular response to DNA damage have long been studied as distinct disciplines. New research and a new appreciation for proteins holding multiple functional roles, however, is beginning to change the way we think about the crosstalk among distinct cellular processes. Here, we focus on the crosstalk between the DNA damage response and the nucleolus, including a comprehensive review of the literature that reveals a role for conventional DNA repair proteins in ribosome biogenesis, and conversely, ribosome biogenesis proteins in DNA repair. Furthermore, with recent advances in nucleolar proteomics and a growing list of proteins that localize to the nucleolus, it is likely that we will continue to identify new DNA repair proteins with a nucleolar-specific role. Given the importance of ribosome biogenesis and DNA repair in essential cellular processes and the role that they play in diverse pathologies, continued elucidation of the overlap between these two disciplines will be essential to the advancement of both fields and to the development of novel therapeutics.
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Affiliation(s)
- L M Ogawa
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - S J Baserga
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA. and Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA and Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
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58
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Scott DD, Oeffinger M. Nucleolin and nucleophosmin: nucleolar proteins with multiple functions in DNA repair. Biochem Cell Biol 2016; 94:419-432. [PMID: 27673355 DOI: 10.1139/bcb-2016-0068] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The nucleolus represents a highly multifunctional intranuclear organelle in which, in addition to the canonical ribosome assembly, numerous processes such as transcription, DNA repair and replication, the cell cycle, and apoptosis are coordinated. The nucleolus is further a key hub in the sensing of cellular stress and undergoes major structural and compositional changes in response to cellular perturbations. Numerous nucleolar proteins have been identified that, upon sensing nucleolar stress, deploy additional, non-ribosomal roles in the regulation of varied cell processes including cell cycle arrest, arrest of DNA replication, induction of DNA repair, and apoptosis, among others. The highly abundant proteins nucleophosmin (NPM1) and nucleolin (NCL) are two such factors that transit to the nucleoplasm in response to stress, and participate directly in the repair of numerous different DNA damages. This review discusses the contributions made by NCL and (or) NPM1 to the different DNA repair pathways employed by mammalian cells to repair DNA insults, and examines the implications of such activities for the regulation, pathogenesis, and therapeutic targeting of NPM1 and NCL.
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Affiliation(s)
- Daniel D Scott
- a Laboratory of RNP Biochemistry, Institut de recherches cliniques de Montréal (IRCM), Montréal, QC H2W 1R7, Canada
- b Division of Experimental Medicine, Faculty of Medicine, McGill University, Montréal, QC H3A 2A3, Canada
| | - Marlene Oeffinger
- a Laboratory of RNP Biochemistry, Institut de recherches cliniques de Montréal (IRCM), Montréal, QC H2W 1R7, Canada
- b Division of Experimental Medicine, Faculty of Medicine, McGill University, Montréal, QC H3A 2A3, Canada
- c Département de biochimie et médecine moléculaire, Faculté de Médecine, Université de Montréal, QC H3T 1J4, Canada
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59
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Rotondo R, Moschini R, Renzone G, Tuccinardi T, Balestri F, Cappiello M, Scaloni A, Mura U, Del-Corso A. Human carbonyl reductase 1 as efficient catalyst for the reduction of glutathionylated aldehydes derived from lipid peroxidation. Free Radic Biol Med 2016; 99:323-332. [PMID: 27562619 DOI: 10.1016/j.freeradbiomed.2016.08.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Revised: 08/11/2016] [Accepted: 08/12/2016] [Indexed: 12/14/2022]
Abstract
Human recombinant carbonyl reductase 1 (E.C. 1.1.1.184, hCBR1) is shown to efficiently act as aldehyde reductase on glutathionylated alkanals, namely 3-glutathionyl-4-hydroxynonanal (GSHNE), 3-glutathionyl-nonanal, 3-glutathionyl-hexanal and 3-glutathionyl-propanal. The presence of the glutathionyl moiety appears as a necessary requirement for the susceptibility of these compounds to the NADPH-dependent reduction by hCBR1. In fact the corresponding alkanals and alkenals, and the cysteinyl and γ-glutamyl-cysteinyl alkanals adducts were either ineffective or very poorly active as CBR1 substrates. Mass spectrometry analysis reveals the ability of hCBR1 to reduce GSHNE to the corresponding GS-dihydroxynonane (GSDHN) and at the same time to catalyze the oxidation of the hemiacetal form of GSHNE, generating the 3-glutathionylnonanoic-δ-lactone. These data are indicative of the ability of the enzyme to catalyze a disproportion reaction of the substrate through the redox recycle of the pyridine cofactor. A rationale for the observed preferential activity of hCBR1 on different GSHNE diastereoisomers is given by molecular modelling. These results evidence the potential of hCBR1 acting on GSHNE to accomplish a dual role, both in terms of HNE detoxification and, through the production of GSDHN, in terms of involvement into the signalling cascade of the cellular inflammatory response.
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Affiliation(s)
- Rossella Rotondo
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy
| | - Roberta Moschini
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy
| | - Giovanni Renzone
- Proteomics & Mass Spectrometry Laboratory, ISPAAM-CNR, via Argine, 1085, Napoli, Italy
| | | | - Francesco Balestri
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy
| | - Mario Cappiello
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy
| | - Andrea Scaloni
- Proteomics & Mass Spectrometry Laboratory, ISPAAM-CNR, via Argine, 1085, Napoli, Italy
| | - Umberto Mura
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy
| | - Antonella Del-Corso
- University of Pisa, Department of Biology, Biochemistry Unit, via S. Zeno, 51, Pisa, Italy.
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60
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Sandomenico A, Focà A, Sanguigno L, Caporale A, Focà G, Pignalosa A, Corvino G, Caragnano A, Beltrami AP, Antoniali G, Tell G, Leonardi A, Ruvo M. Monoclonal antibodies against pools of mono- and polyacetylated peptides selectively recognize acetylated lysines within the context of the original antigen. MAbs 2016; 8:1575-1589. [PMID: 27560983 DOI: 10.1080/19420862.2016.1225643] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Post-translational modifications (PTMs) strongly influence the structure and function of proteins. Lysine side chain acetylation is one of the most widespread PTMs, and it plays a major role in several physiological and pathological mechanisms. Protein acetylation may be detected by mass spectrometry (MS), but the use of monoclonal antibodies (mAbs) is a useful and cheaper option. Here, we explored the feasibility of generating mAbs against single or multiple acetylations within the context of a specific sequence. As a model, we used the unstructured N-terminal domain of APE1, which is acetylated on Lys27, Lys31, Lys32 and Lys35. As immunogen, we used a peptide mixture containing all combinations of single or multi-acetylated variants encompassing the 24-39 protein region. Targeted screening of the resulting clones yielded mAbs that bind with high affinity to only the acetylated APE1 peptides and the acetylated protein. No binding was seen with the non-acetylated variant or unrelated acetylated peptides and proteins, suggesting a high specificity for the APE1 acetylated molecules. MAbs could not finely discriminate between the differently acetylated variants; however, they specifically bound the acetylated protein in mammalian cell extracts and in intact cells and tissue slices from both breast cancers and from a patient affected by idiopathic dilated cardiomyopathy. The data suggest that our approach is a rapid and cost-effective method to generate mAbs against specific proteins modified by multiple acetylations or other PTMs.
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Affiliation(s)
- Annamaria Sandomenico
- a Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche (IBB-CNR) , Napoli , Italy
| | - Annalia Focà
- a Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche (IBB-CNR) , Napoli , Italy
| | | | - Andrea Caporale
- c Centro Interuniversitario di Ricerca sui Peptidi Bioattivi (CIRPeB) , Napoli , Italy
| | - Giuseppina Focà
- a Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche (IBB-CNR) , Napoli , Italy
| | - Angelica Pignalosa
- a Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche (IBB-CNR) , Napoli , Italy
| | | | - Angela Caragnano
- d University of Udine , Department of Medical and Biological Sciences , Udine , Italy
| | | | - Giulia Antoniali
- d University of Udine , Department of Medical and Biological Sciences , Udine , Italy
| | - Gianluca Tell
- d University of Udine , Department of Medical and Biological Sciences , Udine , Italy
| | - Antonio Leonardi
- e University of Napoli "Federico II," Department of Molecular Medicine and Medical Biotechnology , Napoli , Italy
| | - Menotti Ruvo
- a Istituto di Biostrutture e Bioimmagini , Consiglio Nazionale delle Ricerche (IBB-CNR) , Napoli , Italy
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61
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Structural comparison of AP endonucleases from the exonuclease III family reveals new amino acid residues in human AP endonuclease 1 that are involved in incision of damaged DNA. Biochimie 2016; 128-129:20-33. [PMID: 27343627 DOI: 10.1016/j.biochi.2016.06.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 06/20/2016] [Indexed: 12/21/2022]
Abstract
Oxidatively damaged DNA bases are substrates for two overlapping repair pathways: DNA glycosylase-initiated base excision repair (BER) and apurinic/apyrimidinic (AP) endonuclease-initiated nucleotide incision repair (NIR). In the BER pathway, an AP endonuclease cleaves DNA at AP sites and 3'-blocking moieties generated by DNA glycosylases, whereas in the NIR pathway, the same AP endonuclease incises DNA 5' to an oxidized base. The majority of characterized AP endonucleases possess classic BER activities, and approximately a half of them can also have a NIR activity. At present, the molecular mechanism underlying DNA substrate specificity of AP endonucleases remains unclear mainly due to the absence of a published structure of the enzyme in complex with a damaged base. To identify critical residues involved in the NIR function, we performed biochemical and structural characterization of Bacillus subtilis AP endonuclease ExoA and compared its crystal structure with the structures of other AP endonucleases: Escherichia coli exonuclease III (Xth), human APE1, and archaeal Mth212. We found conserved amino acid residues in the NIR-specific enzymes APE1, Mth212, and ExoA. Four of these positions were studied by means of point mutations in APE1: we applied substitution with the corresponding residue found in NIR-deficient E. coli Xth (Y128H, N174Q, G231S, and T268D). The APE1-T268D mutant showed a drastically decreased NIR activity and an inverted Mg(2+) dependence of the AP site cleavage activity, which is in line with the presence of an aspartic residue at the equivalent position among other known NIR-deficient AP endonucleases. Taken together, these data show that NIR is an evolutionarily conserved function in the Xth family of AP endonucleases.
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62
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Scott TL, Wicker CA, Suganya R, Dhar B, Pittman T, Horbinski C, Izumi T. Polyubiquitination of apurinic/apyrimidinic endonuclease 1 by Parkin. Mol Carcinog 2016; 56:325-336. [PMID: 27148961 DOI: 10.1002/mc.22495] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 02/26/2016] [Accepted: 04/13/2016] [Indexed: 01/20/2023]
Abstract
Apurinic/apyrimidinic endonuclease 1 (APE1) is an essential protein crucial for repair of oxidized DNA damage not only in genomic DNA but also in mitochondrial DNA. Parkin, a tumor suppressor and Parkinson's disease (PD) associated gene, is an E3 ubiquitin ligase crucial for mitophagy. Although DNA damage is known to induce mitochondrial stress, Parkin's role in regulating DNA repair proteins has not been elucidated. In this study, we examined the possibility of Parkin-dependent ubiquitination of APE1. Ectopically expressed APE1 was degraded by Parkin and PINK1 via polyubiquitination in mouse embryonic fibroblast cells. PD-causing mutations in Parkin and PINK1 abrogated APE1 ubiquitination. Interaction of APE1 with Parkin was observed by co-immunoprecipitation, proximity ligation assay, and co-localization in the cytoplasm. N-terminal deletion of 41 amino acid residues in APE1 significantly reduced the Parkin-dependent APE1 degradation. These results suggested that Parkin directly ubiquitinated N-terminal Lys residues in APE1 in the cytoplasm. Modulation of Parkin and PINK1 activities under mitochondrial or oxidative stress caused moderate but statistically significant decrease of endogenous APE1 in human cell lines including SH-SY5Y, HEK293, and A549 cells. Analyses of glioblastoma tissues showed an inverse relation between the expression levels of APE1 and Parkin. These results suggest that degradation of endogenous APE1 by Parkin occur when cells are stressed to activate Parkin, and imply a role of Parkin in maintaining the quality of APE1, and loss of Parkin may contribute to elevated APE1 levels in glioblastoma. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Timothy L Scott
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Christina A Wicker
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Rangaswamy Suganya
- Radiation Oncology, Houston Methodist Research Institute, Houston, Texas
| | - Bithika Dhar
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
| | - Thomas Pittman
- Department of Neurosurgery, University of Kentucky, Lexington, Kentucky
| | - Craig Horbinski
- Departments of Pathology and Neurosurgery, Northwestern University, Chicago, Illinois
| | - Tadahide Izumi
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, Kentucky
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Transcriptional Up-Regulation of APE1/Ref-1 in Hepatic Tumor: Role in Hepatocytes Resistance to Oxidative Stress and Apoptosis. PLoS One 2015; 10:e0143289. [PMID: 26624999 PMCID: PMC4666459 DOI: 10.1371/journal.pone.0143289] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Accepted: 11/03/2015] [Indexed: 01/11/2023] Open
Abstract
Objective Human Hepatocellular Carcinoma (HCC) is the fifth most frequent neoplasm worldwide and the most serious complication of long-standing chronic liver diseases (CLD). Its development is associated with chronic inflammation and sustained oxidative stress. Deregulation of apurinic apyrimidinic endonuclease 1/redox effector factor 1 (APE1/Ref-1), a master regulator of cellular response to oxidative stress, has been associated with poor prognosis in several cancers including HCC. Design In the present study we investigated the APE1/Ref-1 mRNA levels in cirrhotic and HCC tissues obtained during HCC resection. The possible protective role of APE1/Ref-1 against oxidative stress and apoptosis was evaluated in vitro in immortalized human hepatocytes (IHH) over-expressing APE1/Ref-1. Results APE1/Ref-1 was up-regulated in HCC, regulation occurring at the transcriptional level. APE1/Ref-1 mRNA content increased with the progression of liver disease with the transcriptional up-regulation present in cirrhosis significantly increased in HCC. The up-regulation was higher in the less differentiated cancers. In vitro, over-expression of APE1/Ref-1 in normal hepatocytes conferred cell protection against oxidative stress and it was associated with BAX inhibition and escape from apoptosis. Conclusion APE1/Ref-1 is up-regulated in HCC and this over-expression correlates with cancer aggressiveness. The up-regulation occurs at the transcriptional level and it is present in the earliest phases of hepatocarcinogenesis. The APE-1/Ref-1 over-expression is associated with hepatocyte survival and inhibits BAX activation and apoptosis. These data suggest a possible role of APE1/Ref-1 over-expression both in hepatocyte survival and HCC development calling attention to this molecule as a promising marker for HCC diagnosis and treatment.
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Antoniali G, Marcuzzi F, Casarano E, Tell G. Cadmium treatment suppresses DNA polymerase δ catalytic subunit gene expression by acting on the p53 and Sp1 regulatory axis. DNA Repair (Amst) 2015; 35:90-105. [PMID: 26519823 DOI: 10.1016/j.dnarep.2015.08.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 07/28/2015] [Accepted: 08/05/2015] [Indexed: 01/03/2023]
Abstract
Cadmium (Cd) is a carcinogenic and neurotoxic environmental pollutant. Among the proposed mechanisms for Cd toxic effects, its ability to promote oxidative stress and to inhibit, in vitro, the activities of some Base Excision DNA Repair (BER) enzymes, such as hOGG1, XRCC1 and APE1, have been already established. However, the molecular mechanisms at the basis of these processes are largely unknown especially at sub-lethal doses of Cd and no information is available on the effect of Cd on the expression levels of BER enzymes. Here, we show that non-toxic treatment of neuronal cell lines, with pro-mitogenic doses of Cd, promotes a significant time- and dose-dependent down-regulation of DNA polymerase δ (POLD1) expression through a transcriptional mechanism with a modest effect on Polβ, XRCC1 and APE1. We further elucidated that the observed transcriptional repression on Polδ is acted by through competition by activated p53 on Sp1 at POLD1 promoter and by a squelching effect. We further proved the positive effect of Sp1 not only on POLD1 expression but also on Polβ, XRCC1 and APE1 expression, suggesting that Sp1 has pleiotropic effects on the whole BER pathway. Our results indicated that Cd-mediated impairment of BER pathway, besides acting on the enzymatic functions of some key proteins, is also exerted at the gene expression level of Polδ by acting on the p53-Sp1 regulatory axis. These data may explain not only the Cd-induced neurotoxic effects but also the potential carcinogenicity of this heavy metal.
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Affiliation(s)
- Giulia Antoniali
- Laboratory of Molecular Biology and DNA Repair, Department of Medical and Biological Sciences, University of Udine, 33100 Udine, Italy
| | - Federica Marcuzzi
- Laboratory of Molecular Biology and DNA Repair, Department of Medical and Biological Sciences, University of Udine, 33100 Udine, Italy
| | - Elena Casarano
- Laboratory of Molecular Biology and DNA Repair, Department of Medical and Biological Sciences, University of Udine, 33100 Udine, Italy
| | - Gianluca Tell
- Laboratory of Molecular Biology and DNA Repair, Department of Medical and Biological Sciences, University of Udine, 33100 Udine, Italy.
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65
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Affiliation(s)
- Gianluca Tell
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy
| | - Bruce Demple
- Department of Pharmacological Sciences, Stony Brook University School of Medicine, Stony Brook, NY 11794, USA
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66
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Moschini R, Peroni E, Rotondo R, Renzone G, Melck D, Cappiello M, Srebot M, Napolitano E, Motta A, Scaloni A, Mura U, Del-Corso A. NADP(+)-dependent dehydrogenase activity of carbonyl reductase on glutathionylhydroxynonanal as a new pathway for hydroxynonenal detoxification. Free Radic Biol Med 2015; 83:66-76. [PMID: 25680283 DOI: 10.1016/j.freeradbiomed.2015.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 01/15/2015] [Accepted: 02/02/2015] [Indexed: 10/24/2022]
Abstract
An NADP(+)-dependent dehydrogenase activity on 3-glutathionyl-4-hydroxynonanal (GSHNE) was purified to electrophoretic homogeneity from a line of human astrocytoma cells (ADF). Proteomic analysis identified this enzymatic activity as associated with carbonyl reductase 1 (EC 1.1.1.184). The enzyme is highly efficient at catalyzing the oxidation of GSHNE (KM 33 µM, kcat 405 min(-1)), as it is practically inactive toward trans-4-hydroxy-2-nonenal (HNE) and other HNE-adducted thiol-containing amino acid derivatives. Combined mass spectrometry and nuclear magnetic resonance spectroscopy analysis of the reaction products revealed that carbonyl reductase oxidizes the hydroxyl group of GSHNE in its hemiacetal form, with the formation of the corresponding 3-glutathionylnonanoic-δ-lactone. The relevance of this new reaction catalyzed by carbonyl reductase 1 is discussed in terms of HNE detoxification and the recovery of reducing power.
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Affiliation(s)
- Roberta Moschini
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy
| | - Eleonora Peroni
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy
| | - Rossella Rotondo
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy
| | - Giovanni Renzone
- Proteomics & Mass Spectrometry Laboratory, ISPAAM-CNR, I-80147 Napoli, Italy
| | - Dominique Melck
- Institute of Biomolecular Chemistry, ICB-CNR, I-80078 Pozzuoli (Naples), Italy
| | - Mario Cappiello
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy
| | - Massimo Srebot
- Health Unit 5 Pisa, Gynecology and Obstetric Unit, Pontedera Hospital, 56025 Pontedera, Italy
| | | | - Andrea Motta
- Institute of Biomolecular Chemistry, ICB-CNR, I-80078 Pozzuoli (Naples), Italy
| | - Andrea Scaloni
- Proteomics & Mass Spectrometry Laboratory, ISPAAM-CNR, I-80147 Napoli, Italy
| | - Umberto Mura
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy
| | - Antonella Del-Corso
- Biochemistry Unit, Department of Biology, University of Pisa, I-56123 Pisa, Italy.
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67
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Poletto M, Malfatti MC, Dorjsuren D, Scognamiglio PL, Marasco D, Vascotto C, Jadhav A, Maloney DJ, Wilson DM, Simeonov A, Tell G. Inhibitors of the apurinic/apyrimidinic endonuclease 1 (APE1)/nucleophosmin (NPM1) interaction that display anti-tumor properties. Mol Carcinog 2015; 55:688-704. [PMID: 25865359 DOI: 10.1002/mc.22313] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 02/10/2015] [Accepted: 02/21/2015] [Indexed: 12/23/2022]
Abstract
The apurinic/apyrimidinic endonuclease 1 (APE1) is a protein central to the base excision DNA repair pathway and operates in the modulation of gene expression through redox-dependent and independent mechanisms. Aberrant expression and localization of APE1 in tumors are recurrent hallmarks of aggressiveness and resistance to therapy. We identified and characterized the molecular association between APE1 and nucleophosmin (NPM1), a multifunctional protein involved in the preservation of genome stability and rRNA maturation. This protein-protein interaction modulates subcellular localization and endonuclease activity of APE1. Moreover, we reported a correlation between APE1 and NPM1 expression levels in ovarian cancer, with NPM1 overexpression being a marker of poor prognosis. These observations suggest that tumors that display an augmented APE1/NPM1 association may exhibit increased aggressiveness and resistance. Therefore, targeting the APE1/NPM1 interaction might represent an innovative strategy for the development of anticancer drugs, as tumor cells relying on higher levels of APE1 and NPM1 for proliferation and survival may be more sensitive than untransformed cells. We set up a chemiluminescence-based high-throughput screening assay in order to find small molecules able to interfere with the APE1/NPM1 interaction. This screening led to the identification of a set of bioactive compounds that impair the APE1/NPM1 association in living cells. Interestingly, some of these molecules display anti-proliferative activity and sensitize cells to therapeutically relevant genotoxins. Given the prognostic significance of APE1 and NPM1, these compounds might prove effective in the treatment of tumors that show abundant levels of both proteins, such as ovarian or hepatic carcinomas.
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Affiliation(s)
- Mattia Poletto
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Matilde C Malfatti
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Dorjbal Dorjsuren
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland
| | - Pasqualina L Scognamiglio
- Department of Pharmacy, CIRPEB (Centro Interuniversitario di Ricerca sui Peptidi Bioattivi), University of Naples 'Federico II', Naples, Italy.,Center for Advanced Biomaterials for Healthcare@CRIB, Istituto Italiano di Tecnologia (IIT), Naples, Italy
| | - Daniela Marasco
- Department of Pharmacy, CIRPEB (Centro Interuniversitario di Ricerca sui Peptidi Bioattivi), University of Naples 'Federico II', Naples, Italy
| | - Carlo Vascotto
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - Ajit Jadhav
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland
| | - David J Maloney
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health, Baltimore, Maryland
| | - Anton Simeonov
- NIH Chemical Genomics Center, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, Maryland
| | - Gianluca Tell
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
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68
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Marasco D, Scognamiglio PL. Identification of inhibitors of biological interactions involving intrinsically disordered proteins. Int J Mol Sci 2015; 16:7394-412. [PMID: 25849651 PMCID: PMC4425024 DOI: 10.3390/ijms16047394] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 03/01/2015] [Accepted: 03/06/2015] [Indexed: 11/16/2022] Open
Abstract
Protein-protein interactions involving disordered partners have unique features and represent prominent targets in drug discovery processes. Intrinsically Disordered Proteins (IDPs) are involved in cellular regulation, signaling and control: they bind to multiple partners and these high-specificity/low-affinity interactions play crucial roles in many human diseases. Disordered regions, terminal tails and flexible linkers are particularly abundant in DNA-binding proteins and play crucial roles in the affinity and specificity of DNA recognizing processes. Protein complexes involving IDPs are short-lived and typically involve short amino acid stretches bearing few "hot spots", thus the identification of molecules able to modulate them can produce important lead compounds: in this scenario peptides and/or peptidomimetics, deriving from structure-based, combinatorial or protein dissection approaches, can play a key role as hit compounds. Here, we propose a panoramic review of the structural features of IDPs and how they regulate molecular recognition mechanisms focusing attention on recently reported drug-design strategies in the field of IDPs.
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Affiliation(s)
- Daniela Marasco
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi (CIRPEB), University of Naples "Federico II", DFM-Scarl, 80134 Naples, Italy.
| | - Pasqualina Liana Scognamiglio
- Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi (CIRPEB), University of Naples "Federico II", DFM-Scarl, 80134 Naples, Italy.
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69
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A charge-dependent mechanism is responsible for the dynamic accumulation of proteins inside nucleoli. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:101-10. [DOI: 10.1016/j.bbamcr.2014.10.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 10/02/2014] [Accepted: 10/06/2014] [Indexed: 01/19/2023]
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70
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Edmonds MJ, Parsons JL. Regulation of base excision repair proteins by ubiquitylation. Exp Cell Res 2014; 329:132-8. [DOI: 10.1016/j.yexcr.2014.07.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/21/2014] [Accepted: 07/24/2014] [Indexed: 11/26/2022]
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71
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Thakur S, Sarkar B, Cholia RP, Gautam N, Dhiman M, Mantha AK. APE1/Ref-1 as an emerging therapeutic target for various human diseases: phytochemical modulation of its functions. Exp Mol Med 2014; 46:e106. [PMID: 25033834 PMCID: PMC4119211 DOI: 10.1038/emm.2014.42] [Citation(s) in RCA: 113] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 01/27/2014] [Accepted: 03/05/2014] [Indexed: 12/12/2022] Open
Abstract
Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunctional enzyme involved in the base excision repair (BER) pathway, which repairs oxidative base damage caused by endogenous and exogenous agents. APE1 acts as a reductive activator of many transcription factors (TFs) and has also been named redox effector factor 1, Ref-1. For example, APE1 activates activator protein-1, nuclear factor kappa B, hypoxia-inducible factor 1α, paired box gene 8, signal transducer activator of transcription 3 and p53, which are involved in apoptosis, inflammation, angiogenesis and survival pathways. APE1/Ref-1 maintains cellular homeostasis (redox) via the activation of TFs that regulate various physiological processes and that crosstalk with redox balancing agents (for example, thioredoxin, catalase and superoxide dismutase) by controlling levels of reactive oxygen and nitrogen species. The efficiency of APE1/Ref-1's function(s) depends on pairwise interaction with participant protein(s), the functions regulated by APE1/Ref-1 include the BER pathway, TFs, energy metabolism, cytoskeletal elements and stress-dependent responses. Thus, APE1/Ref-1 acts as a ‘hub-protein' that controls pathways that are important for cell survival. In this review, we will discuss APE1/Ref-1's versatile nature in various human etiologies, including neurodegeneration, cancer, cardiovascular and other diseases that have been linked with alterations in the expression, subcellular localization and activities of APE/Ref-1. APE1/Ref-1 can be targeted for therapeutic intervention using natural plant products that modulate the expression and functions of APE1/Ref-1. In addition, studies focusing on translational applications based on APE1/Ref-1-mediated therapeutic interventions are discussed.
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Affiliation(s)
- Shweta Thakur
- Center for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Punjab, India
| | - Bibekananda Sarkar
- Center for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Punjab, India
| | - Ravi P Cholia
- Center for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Punjab, India
| | - Nandini Gautam
- Center for Environmental Science and Technology, School of Environment and Earth Sciences, Central University of Punjab, Punjab, India
| | - Monisha Dhiman
- Center for Genetic Diseases and Molecular Medicine, School of Emerging Life Science Technologies, Central University of Punjab, Punjab, India
| | - Anil K Mantha
- 1] Center for Biosciences, School of Basic and Applied Sciences, Central University of Punjab, Punjab, India [2] Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX, USA
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72
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Poletto M, Lirussi L, Wilson DM, Tell G. Nucleophosmin modulates stability, activity, and nucleolar accumulation of base excision repair proteins. Mol Biol Cell 2014; 25:1641-52. [PMID: 24648491 PMCID: PMC4019495 DOI: 10.1091/mbc.e13-12-0717] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Revised: 02/19/2014] [Accepted: 03/10/2014] [Indexed: 01/25/2023] Open
Abstract
Nucleophosmin (NPM1) is a multifunctional protein that controls cell growth and genome stability via a mechanism that involves nucleolar-cytoplasmic shuttling. It is clear that NPM1 also contributes to the DNA damage response, yet its exact function is poorly understood. We recently linked NPM1 expression to the functional activation of the major abasic endonuclease in mammalian base excision repair (BER), apurinic/apyrimidinic endonuclease 1 (APE1). Here we unveil a novel role for NPM1 as a modulator of the whole BER pathway by 1) controlling BER protein levels, 2) regulating total BER capacity, and 3) modulating the nucleolar localization of several BER enzymes. We find that cell treatment with the genotoxin cisplatin leads to concurrent relocalization of NPM1 and BER components from nucleoli to the nucleoplasm, and cellular experiments targeting APE1 suggest a role for the redistribution of nucleolar BER factors in determining cisplatin toxicity. Finally, based on the use of APE1 as a representative protein of the BER pathway, our data suggest a function for BER proteins in the regulation of ribogenesis.
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Affiliation(s)
- Mattia Poletto
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy
| | - Lisa Lirussi
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy
| | - David M Wilson
- Laboratory of Molecular Gerontology, National Institute on Aging, Intramural Research Program, National Institutes of Health, Baltimore, MD 21224
| | - Gianluca Tell
- Department of Medical and Biological Sciences, University of Udine, Udine 33100, Italy
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Abstract
SIGNIFICANCE Human apurinic/apyrimidinic endonuclease 1 (APE1, also known as REF-1) was isolated based on its ability to cleave at AP sites in DNA or activate the DNA binding activity of certain transcription factors. We review herein topics related to this multi-functional DNA repair and stress-response protein. RECENT ADVANCES APE1 displays homology to Escherichia coli exonuclease III and is a member of the divalent metal-dependent α/β fold-containing phosphoesterase superfamily of enzymes. APE1 has acquired distinct active site and loop elements that dictate substrate selectivity, and a unique N-terminus which at minimum imparts nuclear targeting and interaction specificity. Additional activities ascribed to APE1 include 3'-5' exonuclease, 3'-repair diesterase, nucleotide incision repair, damaged or site-specific RNA cleavage, and multiple transcription regulatory roles. CRITICAL ISSUES APE1 is essential for mouse embryogenesis and contributes to cell viability in a genetic background-dependent manner. Haploinsufficient APE1(+/-) mice exhibit reduced survival, increased cancer formation, and cellular/tissue hyper-sensitivity to oxidative stress, supporting the notion that impaired APE1 function associates with disease susceptibility. Although abnormal APE1 expression/localization has been seen in cancer and neuropathologies, and impaired-function variants have been described, a causal link between an APE1 defect and human disease remains elusive. FUTURE DIRECTIONS Ongoing efforts aim at delineating the biological role(s) of the different APE1 activities, as well as the regulatory mechanisms for its intra-cellular distribution and participation in diverse molecular pathways. The determination of whether APE1 defects contribute to human disease, particularly pathologies that involve oxidative stress, and whether APE1 small-molecule regulators have clinical utility, is central to future investigations.
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Affiliation(s)
- Mengxia Li
- Intramural Research Program, Laboratory of Molecular Gerontology, National Institute on Aging, National Institutes of Health , Baltimore, Maryland
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74
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Antoniali G, Lirussi L, Poletto M, Tell G. Emerging roles of the nucleolus in regulating the DNA damage response: the noncanonical DNA repair enzyme APE1/Ref-1 as a paradigmatical example. Antioxid Redox Signal 2014; 20:621-39. [PMID: 23879289 PMCID: PMC3901381 DOI: 10.1089/ars.2013.5491] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 07/22/2013] [Indexed: 12/25/2022]
Abstract
SIGNIFICANCE An emerging concept in DNA repair mechanisms is the evidence that some key enzymes, besides their role in the maintenance of genome stability, display also unexpected noncanonical functions associated with RNA metabolism in specific subcellular districts (e.g., nucleoli). During the evolution of these key enzymes, the acquisition of unfolded domains significantly amplified the possibility to interact with different partners and substrates, possibly explaining their phylogenetic gain of functions. RECENT ADVANCES After nucleolar stress or DNA damage, many DNA repair proteins can freely relocalize from nucleoli to the nucleoplasm. This process may represent a surveillance mechanism to monitor the synthesis and correct assembly of ribosomal units affecting cell cycle progression or inducing p53-mediated apoptosis or senescence. CRITICAL ISSUES A paradigm for this kind of regulation is represented by some enzymes of the DNA base excision repair (BER) pathway, such as apurinic/apyrimidinic endonuclease 1 (APE1). In this review, the role of the nucleolus and the noncanonical functions of the APE1 protein are discussed in light of their possible implications in human pathologies. FUTURE DIRECTIONS A productive cross-talk between DNA repair enzymes and proteins involved in RNA metabolism seems reasonable as the nucleolus is emerging as a dynamic functional hub that coordinates cell growth arrest and DNA repair mechanisms. These findings will drive further analyses on other BER proteins and might imply that nucleic acid processing enzymes are more versatile than originally thought having evolved DNA-targeted functions after a previous life in the early RNA world.
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Affiliation(s)
- Giulia Antoniali
- Department of Medical and Biological Sciences, University of Udine , Udine, Italy
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75
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Antoniali G, Lirussi L, D'Ambrosio C, Dal Piaz F, Vascotto C, Casarano E, Marasco D, Scaloni A, Fogolari F, Tell G. SIRT1 gene expression upon genotoxic damage is regulated by APE1 through nCaRE-promoter elements. Mol Biol Cell 2013; 25:532-47. [PMID: 24356447 PMCID: PMC3923644 DOI: 10.1091/mbc.e13-05-0286] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
APE1 is recruited to the transcription initiation site of the SIRT1 promoter during early cell response to oxidative stress. This reveals the importance of BER enzyme involvement in controlling specific gene expression at the transcriptional level. Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunctional protein contributing to genome stability via repair of DNA lesions via the base excision repair pathway. It also plays a role in gene expression regulation and RNA metabolism. Another, poorly characterized function is its ability to bind to negative calcium responsive elements (nCaRE) of some gene promoters. The presence of many functional nCaRE sequences regulating gene transcription can be envisioned, given their conservation within ALU repeats. To look for functional nCaRE sequences within the human genome, we performed bioinformatic analyses and identified 57 genes potentially regulated by APE1. We focused on sirtuin-1 (SIRT1) deacetylase due to its involvement in cell stress, including senescence, apoptosis, and tumorigenesis, and its role in the deacetylation of APE1 after genotoxic stress. The human SIRT1 promoter presents two nCaRE elements stably bound by APE1 through its N-terminus. We demonstrate that APE1 is part of a multiprotein complex including hOGG1, Ku70, and RNA Pol II, which is recruited on SIRT1 promoter to regulate SIRT1 gene functions during early response to oxidative stress. These findings provide new insights into the role of nCaRE sequences in the transcriptional regulation of mammalian genes.
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Affiliation(s)
- Giulia Antoniali
- Department of Biomedical Sciences and Technologies, University of Udine, 33100 Udine, Italy Proteomics and Mass Spectrometry Laboratory, ISPAAM, National Research Council, 80147 Naples, Italy Department of Biomedical and Pharmaceutical Sciences, University of Salerno, 84084 Fisciano (Salerno), Italy Department of Pharmacy, University of Naples "Federico II," 80134 Naples, Italy Institute of Biostructures and Bioimaging, National Research Council, 80134 Naples, Italy
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Li Z, Malla S, Shin B, Li JM. Battle against RNA oxidation: molecular mechanisms for reducing oxidized RNA to protect cells. WILEY INTERDISCIPLINARY REVIEWS-RNA 2013; 5:335-46. [PMID: 24375979 DOI: 10.1002/wrna.1214] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 09/17/2013] [Accepted: 09/18/2013] [Indexed: 01/08/2023]
Abstract
Oxidation is probably the most common type of damage that occurs in cellular RNA. Oxidized RNA may be dysfunctional and is implicated in the pathogenesis of age-related human diseases. Cellular mechanisms controlling oxidized RNA have begun to be revealed. Currently, a number of ribonucleases and RNA-binding proteins have been shown to reduce oxidized RNA and to protect cells under oxidative stress. Although information about how these factors work is still very limited, we suggest several mechanisms that can be used to minimize oxidized RNA in various organisms.
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Affiliation(s)
- Zhongwei Li
- Department of Biomedical Science, Florida Atlantic University, Boca Raton, FL, USA
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Luncsford PJ, Manvilla BA, Patterson DN, Malik SS, Jin J, Hwang BJ, Gunther R, Kalvakolanu S, Lipinski LJ, Yuan W, Lu W, Drohat AC, Lu AL, Toth EA. Coordination of MYH DNA glycosylase and APE1 endonuclease activities via physical interactions. DNA Repair (Amst) 2013; 12:1043-52. [PMID: 24209961 DOI: 10.1016/j.dnarep.2013.09.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/30/2013] [Accepted: 09/20/2013] [Indexed: 11/26/2022]
Abstract
MutY homologue (MYH) is a DNA glycosylase which excises adenine paired with the oxidative lesion 7,8-dihydro-8-oxoguanine (8-oxoG, or G(o)) during base excision repair (BER). Base excision by MYH results in an apurinic/apyrimidinic (AP) site in the DNA where the DNA sugar-phosphate backbone remains intact. A key feature of MYH activity is its physical interaction and coordination with AP endonuclease I (APE1), which subsequently nicks DNA 5' to the AP site. Because AP sites are mutagenic and cytotoxic, they must be processed by APE1 immediately after the action of MYH glycosylase. Our recent reports show that the interdomain connector (IDC) of human MYH (hMYH) maintains interactions with hAPE1 and the human checkpoint clamp Rad9-Rad1-Hus1 (9-1-1) complex. In this study, we used NMR chemical shift perturbation experiments to determine hMYH-binding site on hAPE1. Chemical shift perturbations indicate that the hMYH IDC peptide binds to the DNA-binding site of hAPE1 and an additional site which is distal to the APE1 DNA-binding interface. In these two binding sites, N212 and Q137 of hAPE1 are key mediators of the MYH/APE1 interaction. Intriguingly, despite the fact that hHus1 and hAPE1 both interact with the MYH IDC, hHus1 does not compete with hAPE1 for binding to hMYH. Rather, hHus1 stabilizes the hMYH/hAPE1 complex both in vitro and in cells. This is consistent with a common theme in BER, namely that the assembly of protein-DNA complexes enhances repair by efficiently coordinating multiple enzymatic steps while simultaneously minimizing the release of harmful repair intermediates.
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Affiliation(s)
- Paz J Luncsford
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, United States
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78
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Cesaratto L, Codarin E, Vascotto C, Leonardi A, Kelley MR, Tiribelli C, Tell G. Specific inhibition of the redox activity of ape1/ref-1 by e3330 blocks tnf-α-induced activation of IL-8 production in liver cancer cell lines. PLoS One 2013; 8:e70909. [PMID: 23967134 PMCID: PMC3744539 DOI: 10.1371/journal.pone.0070909] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 06/24/2013] [Indexed: 12/23/2022] Open
Abstract
APE1/Ref-1 is a main regulator of cellular response to oxidative stress via DNA-repair function and co-activating activity on the NF-κB transcription factor. APE1 is central in controlling the oxidative stress-based inflammatory processes through modulation of cytokines expression and its overexpression is responsible for the onset of chemoresistance in different tumors including hepatic cancer. We examined the functional role of APE1 overexpression during hepatic cell damage related to fatty acid accumulation and the role of the redox function of APE1 in the inflammatory process. HepG2 cells were stably transfected with functional and non-functional APE1 encoding plasmids and the protective effect of APE1 overexpression toward genotoxic compounds or FAs accumulation, was tested. JHH6 cells were stimulated with TNF-α in the presence or absence of E3330, an APE1 redox inhibitor. IL-8 promoter activity was assessed by a luciferase reporter assay, gene expression by Real-Time PCR and cytokines (IL-6, IL-8, IL-12) levels measured by ELISA. APE1 over-expression did not prevent cytotoxicity induced by lipid accumulation. E3330 treatment prevented the functional activation of NF-κB via the alteration of APE1 subcellular trafficking and reduced IL-6 and IL-8 expression induced by TNF-α and FAs accumulation through blockage of the redox-mediated activation of NF-κB. APE1 overexpression observed in hepatic cancer cells may reflect an adaptive response to cell damage and may be responsible for further cell resistance to chemotherapy and for the onset of inflammatory response. The efficacy of the inhibition of APE1 redox activity in blocking TNF-α and FAs induced inflammatory response opens new perspectives for treatment of inflammatory-based liver diseases.
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Affiliation(s)
- Laura Cesaratto
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, Udine, Italy
- Fondazione Italiana Fegato, AREA Science Park, Basovizza, Trieste, Italy
| | - Erika Codarin
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, Udine, Italy
| | - Carlo Vascotto
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, Udine, Italy
| | - Antonio Leonardi
- Dipartimento di Patologia Cellulare e Molecolare ‘L. Califano’ Università “Federico II” di Napoli, Napoli, Italy
| | - Mark R. Kelley
- Department of Pediatrics, Herman B Wells Center for Pediatric Research, Indiana University, Indianapolis, Indiana, United States of America
| | - Claudio Tiribelli
- Fondazione Italiana Fegato, AREA Science Park, Basovizza, Trieste, Italy
- Dipartimento Scienze Cliniche, Università di Trieste, Trieste, Italy
| | - Gianluca Tell
- Dipartimento di Scienze Mediche e Biologiche, Università di Udine, Udine, Italy
- * E-mail:
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79
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Role of the unstructured N-terminal domain of the hAPE1 (human apurinic/apyrimidinic endonuclease 1) in the modulation of its interaction with nucleic acids and NPM1 (nucleophosmin). Biochem J 2013; 452:545-57. [PMID: 23544830 DOI: 10.1042/bj20121277] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The hAPE1 (human apurinic/apyrimidinic endonuclease 1) is an essential enzyme, being the main abasic endonuclease in higher eukaryotes. However, there is strong evidence to show that hAPE1 can directly bind specific gene promoters, thus modulating their transcriptional activity, even in the absence of specific DNA damage. Recent findings, moreover, suggest a role for hAPE1 in RNA processing, which is modulated by the interaction with NPM1 (nucleophosmin). Independent domains account for many activities of hAPE1; however, whereas the endonuclease and the redox-active portions of the protein are well characterized, a better understanding of the role of the unstructured N-terminal region is needed. In the present study, we characterized the requirements for the interaction of hAPE1 with NPM1 and undamaged nucleic acids. We show that DNA/RNA secondary structure has an impact on hAPE1 binding in the absence of damage. Biochemical studies, using the isolated N-terminal region of the protein, reveal that the hAPE1 N-terminal domain represents an evolutionary gain of function, since its composition affects the protein's stability and ability to interact with both nucleic acids and NPM1. Although required, however, this region is not sufficient itself to stably interact with DNA or NPM1.
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80
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Kovalchuk I, Walz P, Thomas J, Kovalchuk O. Genomic instability in liver cells caused by an LPS-induced bystander-like effect. PLoS One 2013; 8:e67342. [PMID: 23874414 PMCID: PMC3706549 DOI: 10.1371/journal.pone.0067342] [Citation(s) in RCA: 7] [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: 01/28/2013] [Accepted: 05/15/2013] [Indexed: 12/21/2022] Open
Abstract
Bacterial infection has been linked to carcinogenesis, however, there is lack of knowledge of molecular mechanisms that associate infection with the development of cancer. We analyzed possible effects of the consumption of heat-killed E. coli O157:H7 cells or its cellular components, DNA, RNA, protein or lipopolysaccharides (LPS) on gene expression in naïve liver cells. Four week old mice were provided water supplemented with whole heat-killed bacteria or bacterial components for a two week period. One group of animals was sacrificed immediately, whereas another group was allowed to consume uncontaminated tap water for an additional two weeks, and liver samples were collected, post mortem. Liver cells responded to exposure of whole heat-killed bacteria and LPS with alteration in γH2AX levels and levels of proteins involved in proliferation, DNA methylation (MeCP2, DNMT1, DNMT3A and 3B) or DNA repair (APE1 and KU70) as well as with changes in the expression of genes involved in stress response, cell cycle control and bile acid biosynthesis. Other bacterial components analysed in this study did not lead to any significant changes in the tested molecular parameters. This study suggests that lipopolysaccharides are a major component of Gram-negative bacteria that induce molecular changes within naïve cells of the host.
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Affiliation(s)
- Igor Kovalchuk
- Department of Biological Sciences, University of Lethbridge, Lethbridge, Canada.
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81
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Vascotto C, Lirussi L, Poletto M, Tiribelli M, Damiani D, Fabbro D, Damante G, Demple B, Colombo E, Tell G. Functional regulation of the apurinic/apyrimidinic endonuclease 1 by nucleophosmin: impact on tumor biology. Oncogene 2013; 33:2876-87. [PMID: 23831574 DOI: 10.1038/onc.2013.251] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 04/24/2013] [Accepted: 05/19/2013] [Indexed: 12/17/2022]
Abstract
Nucleophosmin 1 (NPM1) is a nucleolar protein involved in ribosome biogenesis, stress responses and maintaining genome stability. One-third of acute myeloid leukemias (AMLs) are associated with aberrant localization of NPM1 to the cytoplasm (NPM1c+). This mutation is critical during leukemogenesis and constitutes a good prognostic factor for chemotherapy. At present, there is no clear molecular basis for the role of NPM1 in DNA repair and the tumorigenic process. We found that the nuclear apurinic/apyrimidinic endonuclease 1 (APE1), a core enzyme in base excision DNA repair (BER) of DNA lesions, specifically interacts with NPM1 within nucleoli and the nucleoplasm. Cytoplasmic accumulation of APE1 is associated with cancers including, as we show, NPM1c+ AML. Here we show that NPM1 stimulates APE1 BER activity in cells. We provide evidence that expression of the NPM1c+ variant causes cytoplasmic accumulation of APE1 in: (i) a heterologous cell system (HeLa cells); (ii) the myeloid cell line OCI/AML3 stably expressing NPM1c+; and (iii) primary lymphoblasts of NPM1c+ AML patients. Consistent with impaired APE1 localization, OCI/AML3 cells and blasts of AML patients have impaired BER activity. Cytoplasmic APE1 in NPM1c+ myeloid cells is truncated due to proteolysis. Thus, the good prognostic response of NPM1c+ AML to chemotherapy may result from the cytoplasmic relocalization of APE1 and the consequent BER deficiency. NPM1 thus has an indirect but significant role in BER in vivo that may also be important for NPM1c+ tumorigenesis.
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Affiliation(s)
- C Vascotto
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - L Lirussi
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - M Poletto
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - M Tiribelli
- Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, Italy
| | - D Damiani
- Department of Experimental and Clinical Medical Sciences, University of Udine, Udine, Italy
| | - D Fabbro
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - G Damante
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
| | - B Demple
- Department of Pharmacological Sciences, Stony Brook University School of Medicine, Stony Brook, NY, USA
| | - E Colombo
- Department of Medicine, Surgery and Dentistry, University of Milan, Milan, Italy
| | - G Tell
- Department of Medical and Biological Sciences, University of Udine, Udine, Italy
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