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Liu W, He X, Zhu Y, Li Y, Wang Z, Li P, Pan J, Wang J, Chu B, Yang G, Zhang M, He Q, Li Y, Li W, Zhang C. Identification of a conserved G-quadruplex within the E165R of African swine fever virus (ASFV) as a potential antiviral target. J Biol Chem 2024; 300:107453. [PMID: 38852886 PMCID: PMC11261444 DOI: 10.1016/j.jbc.2024.107453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 05/29/2024] [Accepted: 05/30/2024] [Indexed: 06/11/2024] Open
Abstract
Identification of a conserved G-quadruplex in E165R of ASFVAfrican swine fever virus (ASFV) is a double-stranded DNA arbovirus with high transmissibility and mortality rates. It has caused immense economic losses to the global pig industry. Currently, no effective vaccines or medications are to combat ASFV infection. G-quadruplex (G4) structures have attracted increasing interest because of their regulatory role in vital biological processes. In this study, we identified a conserved G-rich sequence within the E165R gene of ASFV. Subsequently, using various methods, we verified that this sequence could fold into a parallel G4. In addition, the G4-stabilizers pyridostatin and 5,10,15,20-tetrakis-(N-methyl-4-pyridyl) porphin (TMPyP4) can bind and stabilize this G4 structure, thereby inhibiting E165R gene expression, and the inhibitory effect is associated with G4 formation. Moreover, the G4 ligand pyridostatin substantially impeded ASFV proliferation in Vero cells by reducing gene copy number and viral protein expression. These compelling findings suggest that G4 structures may represent a promising and novel antiviral target against ASFV.
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Affiliation(s)
- Wenhao Liu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Xinglin He
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Hubei Hongshan Laboratory, Wuhan, China
| | - Yance Zhu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Yaqin Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China
| | - Zhihao Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Pengfei Li
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Hubei Hongshan Laboratory, Wuhan, China
| | - Jiajia Pan
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Jiang Wang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Beibei Chu
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Guoyu Yang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China
| | - Mengjia Zhang
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Hubei Hongshan Laboratory, Wuhan, China
| | - Qigai He
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Hubei Hongshan Laboratory, Wuhan, China
| | - Yongtao Li
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China.
| | - Wentao Li
- National Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China; Hubei Hongshan Laboratory, Wuhan, China.
| | - Chao Zhang
- College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, China; Key Laboratory of Animal Biochemistry and Nutrition, Ministry of Agriculture and Rural Affairs, Zhengzhou, China; Key Laboratory of Animal Growth and Development of Henan Province, Henan Agricultural University, Zhengzhou, China.
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Romano F, Di Porzio A, Iaccarino N, Riccardi G, Di Lorenzo R, Laneri S, Pagano B, Amato J, Randazzo A. G-quadruplexes in cancer-related gene promoters: from identification to therapeutic targeting. Expert Opin Ther Pat 2023; 33:745-773. [PMID: 37855085 DOI: 10.1080/13543776.2023.2271168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
INTRODUCTION Guanine-rich DNA sequences can fold into four-stranded noncanonical secondary structures called G-quadruplexes (G4s) which are widely distributed in functional regions of the human genome, such as telomeres and gene promoter regions. Compelling evidence suggests their involvement in key genome functions such as gene expression and genome stability. Notably, the abundance of G4-forming sequences near transcription start sites suggests their potential involvement in regulating oncogenes. AREAS COVERED This review provides an overview of current knowledge on G4s in human oncogene promoters. The most representative G4-binding ligands have also been documented. The objective of this work is to present a comprehensive overview of the most promising targets for the development of novel and highly specific anticancer drugs capable of selectively impacting the expression of individual or a limited number of genes. EXPERT OPINION Modulation of G4 formation by specific ligands has been proposed as a powerful new tool to treat cancer through the control of oncogene expression. Actually, most of G4-binding small molecules seem to simultaneously target a range of gene promoter G4s, potentially influencing several critical driver genes in cancer, thus producing significant therapeutic benefits.
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Affiliation(s)
- Francesca Romano
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Anna Di Porzio
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Nunzia Iaccarino
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | | | | | - Sonia Laneri
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Bruno Pagano
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Jussara Amato
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Antonio Randazzo
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
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Monsen RC, DeLeeuw LW, Dean WL, Gray RD, Chakravarthy S, Hopkins JB, Chaires JB, Trent JO. Long promoter sequences form higher-order G-quadruplexes: an integrative structural biology study of c-Myc, k-Ras and c-Kit promoter sequences. Nucleic Acids Res 2022; 50:4127-4147. [PMID: 35325198 PMCID: PMC9023277 DOI: 10.1093/nar/gkac182] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/03/2022] [Accepted: 03/21/2022] [Indexed: 12/15/2022] Open
Abstract
We report on higher-order G-quadruplex structures adopted by long promoter sequences obtained by an iterative integrated structural biology approach. Our approach uses quantitative biophysical tools (analytical ultracentrifugation, small-angle X-ray scattering, and circular dichroism spectroscopy) combined with modeling and molecular dynamics simulations, to derive self-consistent structural models. The formal resolution of our approach is 18 angstroms, but in some cases structural features of only a few nucleotides can be discerned. We report here five structures of long (34-70 nt) wild-type sequences selected from three cancer-related promoters: c-Myc, c-Kit and k-Ras. Each sequence studied has a unique structure. Three sequences form structures with two contiguous, stacked, G-quadruplex units. One longer sequence from c-Myc forms a structure with three contiguous stacked quadruplexes. A longer c-Kit sequence forms a quadruplex-hairpin structure. Each structure exhibits interfacial regions between stacked quadruplexes or novel loop geometries that are possible druggable targets. We also report methodological advances in our integrated structural biology approach, which now includes quantitative CD for counting stacked G-tetrads, DNaseI cleavage for hairpin detection and SAXS model refinement. Our results suggest that higher-order quadruplex assemblies may be a common feature within the genome, rather than simple single quadruplex structures.
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Affiliation(s)
- Robert C Monsen
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Lynn W DeLeeuw
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - William L Dean
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Robert D Gray
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Srinivas Chakravarthy
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Jesse B Hopkins
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Jonathan B Chaires
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
| | - John O Trent
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
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Abiri A, Lavigne M, Rezaei M, Nikzad S, Zare P, Mergny JL, Rahimi HR. Unlocking G-Quadruplexes as Antiviral Targets. Pharmacol Rev 2021; 73:897-923. [PMID: 34045305 DOI: 10.1124/pharmrev.120.000230] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Guanine-rich DNA and RNA sequences can fold into noncanonical nucleic acid structures called G-quadruplexes (G4s). Since the discovery that these structures may act as scaffolds for the binding of specific ligands, G4s aroused the attention of a growing number of scientists. The versatile roles of G4 structures in viral replication, transcription, and translation suggest direct applications in therapy or diagnostics. G4-interacting molecules (proteins or small molecules) may also affect the balance between latent and lytic phases, and increasing evidence reveals that G4s are implicated in generally suppressing viral processes, such as replication, transcription, translation, or reverse transcription. In this review, we focus on the discovery of G4s in viruses and the role of G4 ligands in the antiviral drug discovery process. After assessing the role of viral G4s, we argue that host G4s participate in immune modulation, viral tumorigenesis, cellular pathways involved in virus maturation, and DNA integration of viral genomes, which can be potentially employed for antiviral therapeutics. Furthermore, we scrutinize the impediments and shortcomings in the process of studying G4 ligands and drug discovery. Finally, some unanswered questions regarding viral G4s are highlighted for prospective future projects. SIGNIFICANCE STATEMENT: G-quadruplexes (G4s) are noncanonical nucleic acid structures that have gained increasing recognition during the last few decades. First identified as relevant targets in oncology, their importance in virology is now increasingly clear. A number of G-quadruplex ligands are known: viral transcription and replication are the main targets of these ligands. Both viral and cellular G4s may be targeted; this review embraces the different aspects of G-quadruplexes in both host and viral contexts.
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Affiliation(s)
- Ardavan Abiri
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Marc Lavigne
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Masoud Rezaei
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Sanaz Nikzad
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Peyman Zare
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Jean-Louis Mergny
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
| | - Hamid-Reza Rahimi
- Department of Medicinal Chemistry, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (A.A., S.N.); Institut Pasteur, Department of Virology, UMR 3569 CNRS, Paris, France (M.L.); Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran (M.R.); Dioscuri Center of Chromatin Biology and Epigenomics, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, Poland (P.Z.); Faculty of Medicine, Cardinal Stefan Wyszyński University in Warsaw, Warsaw, Poland (P.Z.); Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau cedex, France (J.-L.M.); Pharmaceutics Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.); and Department of Pharmacology and Toxicology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran (H.-R.R.)
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Antisense Oligonucleotides Used to Identify Telomeric G-Quadruplexes in Metaphase Chromosomes and Fixed Cells by Fluorescence Lifetime Imaging Microscopy of o-BMVC Foci. Molecules 2020; 25:molecules25184083. [PMID: 32906697 PMCID: PMC7570708 DOI: 10.3390/molecules25184083] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/04/2020] [Accepted: 09/04/2020] [Indexed: 01/01/2023] Open
Abstract
Identification of the existence of G-quadruplex (G4) structure, from a specific G-rich sequence in cells, is critical to the studies of structural biology and drug development. Accumulating evidence supports the existence of G4 structure in vivo. Particularly, time-gated fluorescence lifetime imaging microscopy (FLIM) of a G4 fluorescent probe, 3,6-bis(1-methyl-2-vinylpyridinium) carbazole diiodide (o-BMVC), was used to quantitatively measure the number of G4 foci, not only in different cell lines, but also in tissue biopsy. Here, circular dichroism spectra and polyacrylamide gel electrophoresis assays show that the use of antisense oligonucleotides unfolds their G4 structures in different percentages. Using antisense oligonucleotides, quantitative measurement of the number of o-BMVC foci in time-gated FLIM images provides a method for identifying which G4 motifs form G4 structures in fixed cells. Here, the decrease of the o-BMVC foci number, upon the pretreatment of antisense sequences, (CCCTAA)3CCCTA, in fixed cells and at the end of metaphase chromosomes, allows us to identify the formation of telomeric G4 structures from TTAGGG repeats in fixed cells.
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Nucleolin represses transcription of the androgen receptor gene through a G-quadruplex. Oncotarget 2020; 11:1758-1776. [PMID: 32477465 PMCID: PMC7233804 DOI: 10.18632/oncotarget.27589] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 04/14/2020] [Indexed: 02/03/2023] Open
Abstract
The androgen receptor (AR) is a major driver of prostate cancer development and progression. Men who develop advanced prostate cancer often have long-term cancer control when treated with androgen-deprivation therapies (ADT). Still, their disease inevitably becomes resistant to ADT and progresses to castration-resistant prostate cancer (CRPC). ADT involves potent competitive AR antagonists and androgen synthesis inhibitors. Resistance to these types of treatments emerges, primarily through the maintenance of AR signaling by ligand-independent activation mechanisms. There is a need to find better ways to block AR to overcome CRPC. In the findings reported here, we demonstrate that the nuclear scaffold protein, nucleolin (NCL), suppresses the expression of AR. NCL binds to a G-rich region in the AR promoter that forms a G-quadruplex (G4) structure. Binding of NCL to this G4-element is required for NCL to suppress AR expression, specifically in AR-expressing tumor cells. Compounds that stabilize G4 structures require NCL to associate with the G4-element of the AR promoter in order to decrease AR expression. A newly discovered G4 compound that suppresses AR expression demonstrates selective killing of AR-expressing tumor cells, including CRPC lines. Our findings raise the significant possibility that G4-stabilizing drugs can be used to increase NCL transcriptional repressor activity to block AR expression in prostate cancer. Our studies contribute to a clearer understanding of the mechanisms that control AR expression, which could be exploited to overcome CRPC.
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Hsu J, Chou J, Chen T, Hsu J, Su F, Lan J, Wu P, Hu C, Lee EY, Lee W. Glutathione peroxidase 8 negatively regulates caspase-4/11 to protect against colitis. EMBO Mol Med 2020; 12:e9386. [PMID: 31782617 PMCID: PMC6949489 DOI: 10.15252/emmm.201809386] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 10/24/2019] [Accepted: 10/30/2019] [Indexed: 12/11/2022] Open
Abstract
Human caspase-4 and its mouse homolog caspase-11 are receptors for cytoplasmic lipopolysaccharide. Activation of the caspase-4/11-dependent NLRP3 inflammasome is required for innate defense and endotoxic shock, but how caspase-4/11 is modulated remains unclear. Here, we show that mice lacking the oxidative stress sensor glutathione peroxidase 8 (GPx8) are more susceptible to colitis and endotoxic shock, and exhibit reduced richness and diversity of the gut microbiome. C57BL/6 mice that underwent adoptive cell transfer of GPx8-deficient macrophages displayed a similar phenotype of enhanced colitis, indicating a critical role of GPx8 in macrophages. GPx8 binds covalently to caspase-4/11 via disulfide bonding between cysteine 79 of GPx8 and cysteine 118 of caspase-4 and thus restrains caspase-4/11 activation, while GPx8 deficiency leads to caspase-4/11-induced inflammation during colitis and septic shock. Inhibition of caspase-4/11 activation with small molecules reduces the severity of colitis in GPx8-deficient mice. Notably, colonic tissues from patients with ulcerative colitis display low levels of Gpx8 and high caspase-4 expression. In conclusion, these results suggest that GPx8 protects against colitis by negatively regulating caspase-4/11 activity.
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Grants
- 105-2628-B-039-003-MY3 Ministry of Science and Technology, Taiwan (MOST)
- 104-2320-B-039-050 Ministry of Science and Technology, Taiwan (MOST)
- 108-2320-B-039-037 Ministry of Science and Technology, Taiwan (MOST)
- CMU106-N-14 China Medical University, Taiwan (CMU)
- 1025310F China Medical University, Taiwan (CMU)
- Ministry of Education (MOE), Taiwan
- 2371 Academia Sinica, Taiwan
- 4012 Academia Sinica, Taiwan
- Ministry of Science and Technology, Taiwan (MOST)
- China Medical University, Taiwan (CMU)
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Affiliation(s)
- Jye‐Lin Hsu
- Graduate Institute of Biomedical SciencesChina Medical UniversityTaichungTaiwan
- Drug Development CenterChina Medical UniversityTaichungTaiwan
| | - Jen‐Wei Chou
- Division of Gastroenterology and HepatologyDepartment of Internal MedicineChina Medical University HospitalTaichungTaiwan
| | - Tzu‐Fan Chen
- Graduate Institute of Biomedical SciencesChina Medical UniversityTaichungTaiwan
- Drug Development CenterChina Medical UniversityTaichungTaiwan
| | - Jeh‐Ting Hsu
- Department of Information ManagementHsing Wu UniversityTaipeiTaiwan
| | - Fang‐Yi Su
- Genomics Research CenterAcademia SinicaTaipeiTaiwan
| | - Joung‐Liang Lan
- Division of Rheumatology and Immunology and Department of Internal MedicineChina Medical University HospitalTaichungTaiwan
| | - Po‐Chang Wu
- Division of Rheumatology and Immunology and Department of Internal MedicineChina Medical University HospitalTaichungTaiwan
- College of MedicineChina Medical UniversityTaichungTaiwan
| | - Chun‐Mei Hu
- Genomics Research CenterAcademia SinicaTaipeiTaiwan
| | - Eva Y‐HP Lee
- Department of Biological ChemistryUniversity of CaliforniaIrvineCAUSA
| | - Wen‐Hwa Lee
- Drug Development CenterChina Medical UniversityTaichungTaiwan
- Genomics Research CenterAcademia SinicaTaipeiTaiwan
- Department of Biological ChemistryUniversity of CaliforniaIrvineCAUSA
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8
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Bian WX, Xie Y, Wang XN, Xu GH, Fu BS, Li S, Long G, Zhou X, Zhang XL. Binding of cellular nucleolin with the viral core RNA G-quadruplex structure suppresses HCV replication. Nucleic Acids Res 2019; 47:56-68. [PMID: 30462330 PMCID: PMC6326805 DOI: 10.1093/nar/gky1177] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Revised: 10/22/2018] [Accepted: 11/16/2018] [Indexed: 12/12/2022] Open
Abstract
Hepatitis C virus (HCV) infection is a major cause of human chronic liver disease and hepatocellular carcinoma. G-quadruplex (G4) is an important four-stranded secondary structure of nucleic acids. Recently, we discovered that the core gene of HCV contains a G4 RNA structure; however, the interaction between the HCV core RNA G4 and host cellular proteins, and the roles of the HCV core RNA G4 in HCV infection and pathogenesis remain elusive. Here, we identified a cellular protein, nucleolin (NCL), which bound and stabilized the HCV core RNA G4 structure. We demonstrated the direct interaction and colocalization between NCL and wild-type core RNA G4 at both in vitro and in cell physiological conditions of the alive virus; however no significant interaction was found between NCL and G4-modified core RNA. NCL is also associated with HCV particles. HCV infection induced NCL mRNA and protein expression, while NCL suppressed wild-type viral replication and expression, but not G4-modified virus. Silencing of NCL greatly enhanced viral RNA replication. Our findings provide new insights that NCL may act as a host factor for anti-viral innate immunity, and binding of cellular NCL with the viral core RNA G4 structure is involved in suppressing HCV replication.
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Affiliation(s)
- Wen-Xiu Bian
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute and Department of Immunology, Wuhan University School of Basic Medical Sciences, Wuhan 430071, PR China
| | - Yan Xie
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute and Department of Immunology, Wuhan University School of Basic Medical Sciences, Wuhan 430071, PR China
| | - Xiao-Ning Wang
- Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Guo-Hua Xu
- Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, Hubei, China
| | - Bo-Shi Fu
- College of Chemistry and Molecular Sciences, Wuhan University, Hubei Province, Wuhan 430072, China
| | - Shu Li
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute and Department of Immunology, Wuhan University School of Basic Medical Sciences, Wuhan 430071, PR China
| | - Gang Long
- Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiang Zhou
- College of Chemistry and Molecular Sciences, Wuhan University, Hubei Province, Wuhan 430072, China
| | - Xiao-Lian Zhang
- State Key Laboratory of Virology and Hubei Province Key Laboratory of Allergy and Immunology, Medical Research Institute and Department of Immunology, Wuhan University School of Basic Medical Sciences, Wuhan 430071, PR China
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9
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Biswas B, Kandpal M, Vivekanandan P. A G-quadruplex motif in an envelope gene promoter regulates transcription and virion secretion in HBV genotype B. Nucleic Acids Res 2017; 45:11268-11280. [PMID: 28981800 PMCID: PMC5737607 DOI: 10.1093/nar/gkx823] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 09/07/2017] [Indexed: 12/20/2022] Open
Abstract
HBV genotypes differ in pathogenicity. In addition, genotype-specific differences in the regulation of transcription and virus replication exist in HBV, but the underlying mechanisms are unknown. Here, we show the presence of a G-quadruplex motif in the promoter of the preS2/S gene; this G-quadruplex is highly conserved only in HBV genotype B but not in other HBV genotypes. We demonstrate that this G-quadruplex motif forms a hybrid intramolecular G-quadruplex structure. Interestingly, mutations disrupting the G-quadruplex in HBV genotype B reduced the preS2/S promoter activity, leading to reduced hepatitis B surface antigen (HBsAg) levels. G-quadruplex ligands stabilized the G-quadruplex in genotype B and enhanced the preS2/S promoter activity. Furthermore, mutations disrupting the G-quadruplex in the full-length HBV genotype B constructs were associated with impaired virion secretion. In contrast to typical G-quadruplexes within promoters which are negative regulators of transcription the G-quadruplex in the preS2/S promoter of HBV represents an unconventional positive regulatory element. Our findings highlight (a) G-quadruplex mediated enhancement of transcription and virion secretion in HBV and (b) a yet unknown role for DNA secondary structures in complex genotype-specific regulatory mechanisms in virus genomes.
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Affiliation(s)
- Banhi Biswas
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Manish Kandpal
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi 110016, India
| | - Perumal Vivekanandan
- Kusuma School of Biological Sciences, Indian Institute of Technology Delhi, New Delhi 110016, India
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10
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Lago S, Tosoni E, Nadai M, Palumbo M, Richter SN. The cellular protein nucleolin preferentially binds long-looped G-quadruplex nucleic acids. Biochim Biophys Acta Gen Subj 2017; 1861:1371-1381. [PMID: 27913192 PMCID: PMC5466061 DOI: 10.1016/j.bbagen.2016.11.036] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2016] [Revised: 11/25/2016] [Accepted: 11/26/2016] [Indexed: 12/12/2022]
Abstract
BACKGROUND G-quadruplexes (G4s) are four-stranded nucleic acid structures that form in G-rich sequences. Nucleolin (NCL) is a cellular protein reported for its functions upon G4 recognition, such as induction of neurodegenerative diseases, tumor and virus mechanisms activation. We here aimed at defining NCL/G4 binding determinants. METHODS Electrophoresis mobility shift assay was used to detect NCL/G4 binding; circular dichroism to assess G4 folding, topology and stability; dimethylsulfate footprinting to detect G bases involved in G4 folding. RESULTS The purified full-length human NCL was initially tested on telomeric G4 target sequences to allow for modulation of loop, conformation, length, G-tract number, stability. G4s in promoter regions with more complex sequences were next employed. We found that NCL binding to G4s heavily relies on G4 loop length, independently of the conformation and oligonucleotide/loop sequence. Low stability G4s are preferred. When alternative G4 conformations are possible, those with longer loops are preferred upon binding to NCL, even if G-tracts need to be spared from G4 folding. CONCLUSIONS Our data provide insight into how G4s and the associated proteins may control the ON/OFF molecular switch to several pathological processes, including neurodegeneration, tumor and virus activation. Understanding these regulatory determinants is the first step towards the development of targeted therapies. GENERAL SIGNIFICANCE The indication that NCL binding preferentially stimulates and induces folding of G4s containing long loops suggests NCL ability to modify the overall structure and steric hindrance of the involved nucleic acid regions. This protein-induced modification of the G4 structure may represent a cellular mechanosensor mechanism to molecular signaling and disease pathogenesis. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.
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Affiliation(s)
- Sara Lago
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Elena Tosoni
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Matteo Nadai
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Manlio Palumbo
- Department of Pharmaceutical Sciences, University of Padua, via Marzolo 5, 35131 Padua, Italy
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy.
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11
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Chang YC, Chiu CC, Yuo CY, Chan WL, Chang YS, Chang WH, Wu SM, Chou HL, Liu TC, Lu CY, Yang WK, Chang JG. An XIST-related small RNA regulates KRAS G-quadruplex formation beyond X-inactivation. Oncotarget 2016; 7:86713-86729. [PMID: 27880931 PMCID: PMC5349948 DOI: 10.18632/oncotarget.13433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 10/31/2016] [Indexed: 12/31/2022] Open
Abstract
X-inactive-specific transcript (XIST), a long non-coding RNA, is essential for the initiation of X-chromosome inactivation. However, little is known about other roles of XIST in the physiological process in eukaryotic cells. In this study, the bioinformatics approaches revealed XIST could be processed into a small non-coding RNA XPi2. The XPi2 RNA was confirmed by a northern blot assay; its expression was gender-independent, suggesting the role of XPi2 was beyond X-chromosome inactivation. The pull-down assay combined with LC-MS-MS identified two XPi2-associated proteins, nucleolin and hnRNP A1, connected to the formation of G-quadruplex. Moreover, the microarray data showed the knockdown of XPi2 down-regulated the KRAS pathway. Consistently, we tested the expression of ten genes, including KRAS, which was correlated with a G-quadruplex formation and found the knockdown of XPi2 caused a dramatic decrease in the transcription level of KRAS among the ten genes. The results of CD/NMR assay also supported the interaction of XPi2 and the polypurine-polypyrimidine element of KRAS. Accordingly, XPi2 may stimulate the KRAS expression by attenuating G-quadruplex formation. Our present work sheds light on the novel role of small RNA XPi2 in modulating the G-quadruplex formation which may play some essential roles in the KRAS- associated carcinogenesis.
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Affiliation(s)
- Yuli C. Chang
- Graduate Institutes of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Division of Cytogenetics, Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Chien-Chih Chiu
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chung-Yee Yuo
- Graduate Institutes of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Wen-Ling Chan
- Epigenome Research Center, China Medical University and Hospital, Taichung, Taiwan
- Department of Bioinformatics and Medical Engineering, Asia University
| | - Ya-Sian Chang
- Epigenome Research Center, China Medical University and Hospital, Taichung, Taiwan
- Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan
- School of Medicine, China Medical University, Taichung, Taiwan
| | - Wen-Hsin Chang
- Graduate Institutes of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Division of Hematology/Oncology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Shou-Mei Wu
- School of Pharmacy, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Han-Lin Chou
- Department of Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Ta-Chih Liu
- Graduate Institutes of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- Division of Cytogenetics, Department of Laboratory Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
- Division of Hematology/Oncology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Chi-Yu Lu
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Taiwan
| | - Wen-Kuang Yang
- Cell/Gene Therapy Research Laboratory, Department of Medical Research, China Medical University Hospital, Taichung, Taiwan
| | - Jan-Gowth Chang
- Epigenome Research Center, China Medical University and Hospital, Taichung, Taiwan
- Department of Laboratory Medicine, China Medical University Hospital, Taichung, Taiwan
- School of Medicine, China Medical University, Taichung, Taiwan
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12
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Rigo R, Palumbo M, Sissi C. G-quadruplexes in human promoters: A challenge for therapeutic applications. Biochim Biophys Acta Gen Subj 2016; 1861:1399-1413. [PMID: 28025083 DOI: 10.1016/j.bbagen.2016.12.024] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 12/21/2016] [Accepted: 12/22/2016] [Indexed: 12/19/2022]
Abstract
BACKGROUND G-rich sequences undergo unique structural equilibria to form G-quadruplexes (G4) both in vitro and in cell systems. Several pathologies emerged to be directly related to G4 occurrence at defined genomic portions. Additionally, G-rich sequences are significantly represented around transcription start sites (TSS) thus leading to the hypothesis of a gene regulatory function for G4. Thus, the tuning of G4 formation has been proposed as a new powerful tool to regulate gene expression to treat related pathologies. However, up-to date this approach did not provide any new really efficient treatment. SCOPE OF REVIEW Here, we summarize the most recent advances on the correlation between the structural features of G4 in human promoters and the role these systems physiologically exert. In particular we focus on the effect of G4 localization among cell compartments and along the promoters in correlation with protein interaction networks and epigenetic state. Finally the intrinsic structural features of G4 at promoters are discussed to unveil the contribution of different G4 structural modules in this complex architecture. MAJOR CONCLUSIONS It emerges that G4s play several roles in the intriguing and complex mechanism of gene expression, being able to produce opposite effects on the same target. This reflects the occurrence of a highly variegate network of several components working simultaneously. GENERAL SIGNIFICANCE The resulting picture is still fuzzy but some points of strength are definitely emerging, which prompts all of us to strengthen our efforts in view of a selective control of gene expression through G4 modulation. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio.
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Affiliation(s)
- Riccardo Rigo
- Dept. of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo, 5, 35131 Padova, Italy
| | - Manlio Palumbo
- Dept. of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo, 5, 35131 Padova, Italy
| | - Claudia Sissi
- Dept. of Pharmaceutical and Pharmacological Sciences, University of Padova, v. Marzolo, 5, 35131 Padova, Italy.
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13
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Chen YI, Wei PC, Hsu JL, Su FY, Lee WH. NPGPx (GPx7): a novel oxidative stress sensor/transmitter with multiple roles in redox homeostasis. Am J Transl Res 2016; 8:1626-1640. [PMID: 27186289 PMCID: PMC4859894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 10/31/2015] [Indexed: 06/05/2023]
Abstract
NPGPx (GPx7) is a member of the glutathione peroxidase (GPx) family without any GPx activity. GPx7 displays a unique function which serves as a stress sensor/transmitter to transfer the signal to its interacting proteins by shuttling disulfide bonds in response to various stresses. In this review, we focus on the exceptional structural and biochemical features of GPx7 compared to other 7 family members and described how GPx7 regulates the diverse signaling targets including GRP78, PDI, CPEB2, and XRN2, and their different roles in unfolded protein response, oxidative stress, and non-targeting siRNA stress response, respectively. The phenotypes associated with GPx7 deficiency in mouse or human including ROS accumulations, highly elevated cancer incidences, auto-immune disorders, and obesity are also revealed in this paper. Finally, we compare GPx8 with GPx7, which shares the highest structural similarity but different biological roles in stress response. These insights have thus provided a more comprehensive understanding of the role of GPx7 in the maintenance of redox homeostasis.
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Affiliation(s)
- Yi-Ing Chen
- Genomics Research Center, Academia SinicaTaipei 115, Taiwan
- Graduate Program of Translational Medicine, National Taiwan UniversityTaipei 106, Taiwan
| | - Pei-Chi Wei
- Genomics Research Center, Academia SinicaTaipei 115, Taiwan
| | - Jye-Lin Hsu
- Research Center for Tumor Medical Science, China Medical UniversityTaichung 404, Taiwan
- Department of Medical Research, China Medical University HospitalTaichung 404, Taiwan
| | - Fang-Yi Su
- Genomics Research Center, Academia SinicaTaipei 115, Taiwan
- Graduate Institute of Biochemistry and Molecular Biology, School of Life Sciences, National Yang-Ming UniversityTaipei 112, Taiwan
| | - Wen-Hwa Lee
- Genomics Research Center, Academia SinicaTaipei 115, Taiwan
- Institute of Clinical Medicine, China Medical UniversityTaichung 404, Taiwan
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14
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Wang R, Xu Y, Liu B. Recombination spot identification Based on gapped k-mers. Sci Rep 2016; 6:23934. [PMID: 27030570 PMCID: PMC4814916 DOI: 10.1038/srep23934] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 03/16/2016] [Indexed: 12/14/2022] Open
Abstract
Recombination is crucial for biological evolution, which provides many new combinations of genetic diversity. Accurate identification of recombination spots is useful for DNA function study. To improve the prediction accuracy, researchers have proposed several computational methods for recombination spot identification. The k-mer feature is one of the most useful features for modeling the properties and function of DNA sequences. However, it suffers from the inherent limitation. If the value of word length k is large, the occurrences of k-mers are closed to a binary variable, with a few k-mers present once and most k-mers are absent. This usually causes the sparse problem and reduces the classification accuracy. To solve this problem, we add gaps into k-mer and introduce a new feature called gapped k-mer (GKM) for identification of recombination spots. By using this feature, we present a new predictor called SVM-GKM, which combines the gapped k-mers and Support Vector Machine (SVM) for recombination spot identification. Experimental results on a widely used benchmark dataset show that SVM-GKM outperforms other highly related predictors. Therefore, SVM-GKM would be a powerful predictor for computational genomics.
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Affiliation(s)
- Rong Wang
- School of Computer Science and Technology, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
| | - Yong Xu
- School of Computer Science and Technology, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
| | - Bin Liu
- School of Computer Science and Technology, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, Guangdong 518055, China
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15
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Huang WC, Tseng TY, Chen YT, Chang CC, Wang ZF, Wang CL, Hsu TN, Li PT, Chen CT, Lin JJ, Lou PJ, Chang TC. Direct evidence of mitochondrial G-quadruplex DNA by using fluorescent anti-cancer agents. Nucleic Acids Res 2015; 43:10102-13. [PMID: 26487635 PMCID: PMC4666356 DOI: 10.1093/nar/gkv1061] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/30/2015] [Indexed: 11/26/2022] Open
Abstract
G-quadruplex (G4) is a promising target for anti-cancer treatment. In this paper, we provide the first evidence supporting the presence of G4 in the mitochondrial DNA (mtDNA) of live cells. The molecular engineering of a fluorescent G4 ligand, 3,6-bis(1-methyl-4-vinylpyridinium) carbazole diiodide (BMVC), can change its major cellular localization from the nucleus to the mitochondria in cancer cells, while remaining primarily in the cytoplasm of normal cells. A number of BMVC derivatives with sufficient mitochondrial uptake can induce cancer cell death without damaging normal cells. Fluorescence studies of these anti-cancer agents in live cells and in isolated mitochondria from HeLa cells have demonstrated that their major target is mtDNA. In this study, we use fluorescence lifetime imaging microscopy to verify the existence of mtDNA G4s in live cells. Bioactivity studies indicate that interactions between these anti-cancer agents and mtDNA G4 can suppress mitochondrial gene expression. This work underlines the importance of fluorescence in the monitoring of drug-target interactions in cells and illustrates the emerging development of drugs in which mtDNA G4 is the primary target.
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Affiliation(s)
- Wei-Chun Huang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Ting-Yuan Tseng
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Ying-Ting Chen
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Cheng-Chung Chang
- Institute of Biomedical Engineering, National Chung-Hsing University, Taichung 40227, Taiwan
| | - Zi-Fu Wang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Chiung-Lin Wang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Tsu-Ning Hsu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan Department of Agricultural Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Pei-Tzu Li
- Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan
| | - Chin-Tin Chen
- Department of Biochemical Science and Technology, National Taiwan University, Taipei 10617, Taiwan
| | - Jing-Jer Lin
- Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei 10051, Taiwan
| | - Pei-Jen Lou
- Department of Otolaryngology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10051, Taiwan
| | - Ta-Chau Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
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16
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Tosoni E, Frasson I, Scalabrin M, Perrone R, Butovskaya E, Nadai M, Palù G, Fabris D, Richter SN. Nucleolin stabilizes G-quadruplex structures folded by the LTR promoter and silences HIV-1 viral transcription. Nucleic Acids Res 2015; 43:8884-97. [PMID: 26354862 PMCID: PMC4605322 DOI: 10.1093/nar/gkv897] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 08/26/2015] [Accepted: 08/27/2015] [Indexed: 01/26/2023] Open
Abstract
Folding of the LTR promoter into dynamic G-quadruplex conformations has been shown to suppress its transcriptional activity in HIV-1. Here we sought to identify the proteins that control the folding of this region of proviral genome by inducing/stabilizing G-quadruplex structures. The implementation of electrophorethic mobility shift assay and pull-down experiments coupled with mass spectrometric analysis revealed that the cellular protein nucleolin is able to specifically recognize G-quadruplex structures present in the LTR promoter. Nucleolin recognized with high affinity and specificity the majority, but not all the possible G-quadruplexes folded by this sequence. In addition, it displayed greater binding preference towards DNA than RNA G-quadruplexes, thus indicating two levels of selectivity based on the sequence and nature of the target. The interaction translated into stabilization of the LTR G-quadruplexes and increased promoter silencing activity; in contrast, disruption of nucleolin binding in cells by both siRNAs and a nucleolin binding aptamer greatly increased LTR promoter activity. These data indicate that nucleolin possesses a specific and regulated activity toward the HIV-1 LTR promoter, which is mediated by G-quadruplexes. These observations provide new essential insights into viral transcription and a possible low mutagenic target for antiretroviral therapy.
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Affiliation(s)
- Elena Tosoni
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Ilaria Frasson
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Matteo Scalabrin
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy The RNA Institute, University at Albany-SUNY, Albany, NY 12222, USA
| | - Rosalba Perrone
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Elena Butovskaya
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Matteo Nadai
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
| | - Dan Fabris
- The RNA Institute, University at Albany-SUNY, Albany, NY 12222, USA
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, via Gabelli 63, 35121 Padua, Italy
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17
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Shen N, Yan F, Pang J, Wu LC, Al-Kali A, Litzow MR, Liu S. A nucleolin-DNMT1 regulatory axis in acute myeloid leukemogenesis. Oncotarget 2014; 5:5494-509. [PMID: 25015109 PMCID: PMC4170608 DOI: 10.18632/oncotarget.2131] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Accepted: 06/24/2014] [Indexed: 12/15/2022] Open
Abstract
Nucleolin overexpression and DNA hypermethylation have been implicated in cancer pathogenesis, but whether and how these aberrations cooperate in controlling leukemia cell fate remains elusive. Here, we provide the first mechanistic insights into the role of nucleolin in leukemogenesis through creating a DNA hypermethylation profile in leukemia cells. We found that, in leukemia patients, nucleolin levels are significantly elevated and nucleolin overexpression strongly associates with DNMT upregulation and shorter survival. Enforced nucleolin expression augmented leukemia cell proliferation, whereas nucleolin dysfunction by RNA interference and inhibitory molecule AS1411 blocked leukemia cell clonogenic potential in vitro and impaired tumorigenesis in vivo. Mechanistic investigations showed that nucleolin directly activates NFκB signaling, and NFκB activates its downstream effector, DNA methylation machinery. Indeed, nucleolin overexpression increased NFκB phosphorylation and upregulated DNMT1 that is followed by DNA demethylation; by contrast, nucleolin dysfunction dephosphorylated NFκB and abrogated DNMT1 expression, which resulted in decreased global DNA methylation, restored p15INK4B expression and DNA hypomethylation on p15INK4B promoter. Notably, NFκB inactivation diminished, whereas NFκB overexpression enhanced DNMT1 promoter activity and endogenous DNMT1 expression. Collectively, our studies identify nucleolin as an unconventional epigenetic regulator in leukemia cells and demonstrate nucleolin-NFκB-DNMT1 axis as a new molecular pathway underlying AML leukemogenesis.
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Affiliation(s)
- Na Shen
- The Hormel Institute, University of Minnesota, Austin, MN
| | - Fei Yan
- The Hormel Institute, University of Minnesota, Austin, MN
| | - Jiuxia Pang
- The Hormel Institute, University of Minnesota, Austin, MN
| | - Lai-Chu Wu
- Department of Molecular and Cellular Biochemistry, The Ohio State University, Columbus, OH
| | - Aref Al-Kali
- Division of Hematology, Mayo Clinic, Rochester, MN
| | | | - Shujun Liu
- The Hormel Institute, University of Minnesota, Austin, MN
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18
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Piekna-Przybylska D, Sullivan MA, Sharma G, Bambara RA. U3 region in the HIV-1 genome adopts a G-quadruplex structure in its RNA and DNA sequence. Biochemistry 2014; 53:2581-93. [PMID: 24735378 PMCID: PMC4007979 DOI: 10.1021/bi4016692] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Genomic regions rich in G residues
are prone to adopt G-quadruplex
structure. Multiple Sp1-binding motifs arranged in tandem have been
suggested to form this structure in promoters of cancer-related genes.
Here, we demonstrate that the G-rich proviral DNA sequence of the
HIV-1 U3 region, which serves as a promoter of viral transcription,
adopts a G-quadruplex structure. The sequence contains three binding
elements for transcription factor Sp1, which is involved in the regulation
of HIV-1 latency, reactivation, and high-level virus expression. We
show that the three Sp1 binding motifs can adopt different forms of
G-quadruplex structure and that the Sp1 protein can recognize and
bind to its site folded into a G-quadruplex. In addition, a c-kit2
specific antibody, designated hf2, binds to two different G-quadruplexes
formed in Sp1 sites. Since U3 is encoded at both viral genomic ends,
the G-rich sequence is also present in the RNA genome. We demonstrate
that the RNA sequence of U3 forms dimers with characteristics known
for intermolecular G-quadruplexes. Together with previous reports
showing G-quadruplex dimers in the gag and cPPT regions,
these results suggest that integrity of the two viral genomes is maintained
through numerous intermolecular G-quadruplexes formed in different
RNA genome locations. Reconstituted reverse transcription shows that
the potassium-dependent structure formed in U3 RNA facilitates RT
template switching, suggesting that the G-quadruplex contributes to
recombination in U3.
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Affiliation(s)
- Dorota Piekna-Przybylska
- Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester , Rochester, New York 14642, United States
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19
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Wang JM, Huang FC, Kuo MHJ, Wang ZF, Tseng TY, Chang LC, Yen SJ, Chang TC, Lin JJ. Inhibition of cancer cell migration and invasion through suppressing the Wnt1-mediating signal pathway by G-quadruplex structure stabilizers. J Biol Chem 2014; 289:14612-23. [PMID: 24713700 DOI: 10.1074/jbc.m114.548230] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
WNT1 encodes a multifunctional signaling glycoprotein that is highly expressed in several malignant tumors. Patients with Wnt1-positive cancer are usually related to advanced metastasis. Here, we found that a stretch of G-rich sequences located at the WNT1 promoter region is capable of forming G-quadruplex structures. The addition of G-quadruplex structure stabilizers, BMVC and BMVC4, raises the melting temperature of the oligonucleotide formed by the WNT1 promoter G-rich sequences. Significantly, the expression of WNT1 was repressed by BMVC or BMVC4 in a G-quadruplex-dependent manner, suggesting that they can be used to modulate WNT1 expression. The role of G-quadruplex stabilizers on Wnt1-mediated cancer migration and invasion was further analyzed. The protein levels of β-catenin, a mediator of the Wnt-mediated signaling pathway, and the downstream targets MMP7 and survivin were down-regulated upon BMVC or BMVC4 treatments. Moreover, the migration and invasion activities of cancer cells were inhibited by BMVC and BMVC4, and the inhibitory effects can be reversed by WNT1-overexpression. Thus the Wnt1 expression and its downstream signaling pathways can be regulated through the G-quadruplex sequences located at its promoter region. These findings provide a novel approach for future drug development to inhibit migration and invasion of cancer cells.
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Affiliation(s)
- Jing-Ming Wang
- From the Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei 112, Taiwan
| | - Fong-Chun Huang
- Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Margaret Hsin-Jui Kuo
- Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166 Taipei, 106, Taiwan
| | - Zi-Fu Wang
- Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166 Taipei, 106, Taiwan, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan
| | - Ting-Yuan Tseng
- Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166 Taipei, 106, Taiwan, Institute of Biophotonics, National Yang-Ming University, Taipei 112, Taiwan, and
| | - Lien-Cheng Chang
- From the Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei 112, Taiwan, Food and Drug Administration, Ministry of Health and Welfare, Taipei 115, Taiwan
| | - Shao-Jung Yen
- Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Ta-Chau Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166 Taipei, 106, Taiwan, Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, Institute of Biophotonics, National Yang-Ming University, Taipei 112, Taiwan, and
| | - Jing-Jer Lin
- From the Institute of Biopharmaceutical Sciences, National Yang-Ming University, Taipei 112, Taiwan, Institute of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei 100, Taiwan,
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Destroy and exploit: catalyzed removal of hydroperoxides from the endoplasmic reticulum. Int J Cell Biol 2013; 2013:180906. [PMID: 24282412 PMCID: PMC3824332 DOI: 10.1155/2013/180906] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Accepted: 09/05/2013] [Indexed: 01/06/2023] Open
Abstract
Peroxidases are enzymes that reduce hydroperoxide substrates. In many cases, hydroperoxide reduction is coupled to the formation of a disulfide bond, which is transferred onto specific acceptor molecules, the so-called reducing substrates. As such, peroxidases control the spatiotemporal distribution of diffusible second messengers such as hydrogen peroxide (H2O2) and generate new disulfides. Members of two families of peroxidases, peroxiredoxins (Prxs) and glutathione peroxidases (GPxs), reside in different subcellular compartments or are secreted from cells. This review discusses the properties and physiological roles of PrxIV, GPx7, and GPx8 in the endoplasmic reticulum (ER) of higher eukaryotic cells where H2O2 and—possibly—lipid hydroperoxides are regularly produced. Different peroxide sources and reducing substrates for ER peroxidases are critically evaluated. Peroxidase-catalyzed detoxification of hydroperoxides coupled to the productive use of disulfides, for instance, in the ER-associated process of oxidative protein folding, appears to emerge as a common theme. Nonetheless, in vitro and in vivo studies have demonstrated that individual peroxidases serve specific, nonoverlapping roles in ER physiology.
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