1
|
Trizna L, Olajoš J, Víglaský V. DNA minicircles capable of forming a variety of non-canonical structural motifs. Front Chem 2024; 12:1384201. [PMID: 38595699 PMCID: PMC11002140 DOI: 10.3389/fchem.2024.1384201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 03/12/2024] [Indexed: 04/11/2024] Open
Abstract
Although more than 10% of the human genome has the potential to fold into non-B DNA, the formation of non-canonical structural motifs as part of long dsDNA chains are usually considered as unfavorable from a thermodynamic point of view. However, recent experiments have confirmed that non-canonical motifs do exist and are non-randomly distributed in genomic DNA. This distribution is highly dependent not only on the DNA sequence but also on various other factors such as environmental conditions, DNA topology and the expression of specific cellular factors in different cell types. In this study, we describe a new strategy used in the preparation of DNA minicircles containing different non-canonical motifs which arise as a result of imperfect base pairing between complementary strands. The approach exploits the fact that imperfections in the pairing of complementary strands thermodynamically weaken the dsDNA structure at the expense of enhancing the formation of non-canonical motifs. In this study, a completely different concept of stable integration of a non-canonical motif into dsDNA is presented. Our approach allows the integration of various types of non-canonical motifs into the dsDNA structure such as hairpin, cruciform, G-quadruplex and i-motif forms but also combinations of these forms. Small DNA minicircles have recently become the subject of considerable interest in both fundamental research and in terms of their potential therapeutic applications.
Collapse
Affiliation(s)
| | | | - Viktor Víglaský
- Department of Biochemistry, Institute of Chemistry, Faculty of Sciences, P. J. Šafárik University, Košice, Slovakia
| |
Collapse
|
2
|
Bose D, Banerjee N, Roy A, Sengupta P, Chatterjee S. Switchable tetraplex elements in the heterogeneous nuclear ribonucleoprotein K promoter: micro-environment dictated structural transitions of G/C rich elements. J Biomol Struct Dyn 2024:1-18. [PMID: 38235706 DOI: 10.1080/07391102.2024.2303378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 01/03/2024] [Indexed: 01/19/2024]
Abstract
We have elucidated the hnRNP K promoter as a hotspot for tetraplex-based molecular switches receptive to micro-environmental stimuli. We have characterised the structural features of four tetraplex-forming loci and identified them as binding sites of transcription factors. These segments form either G-quadruplex or i-motif structures, the structural dynamicity of which has been studied in depth via several biophysical techniques. The tetraplexes display high dynamicity and are influenced by both pH and KCl concentrations in vitro. The loci complementary to these sequences form additional non-canonical secondary structures. In the cellular context, the most eminent observation of this study is the binding of hnRNP K to the i-motif forming sequences in its own promoter. We are the first to report a probable transcriptional autoregulatory function of hnRNP K in coordination with higher-order DNA structures. Herein, we also report the positive interaction of the endogenous tetraplexes with Sp1, a well-known transcriptional regulator. Treatment with tetraplex-specific small molecule ligands further uncovered G-quadruplexes' functioning as repressors and i-motifs as activators in this context. Together, our findings strongly indicate the critical regulatory role of the identified tetraplex elements in the hnRNP K promoter.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Debopriya Bose
- Department of Biological Sciences, Bose Institute, Kolkata, West Bengal, India
| | - Nilanjan Banerjee
- Department of Biological Sciences, Bose Institute, Kolkata, West Bengal, India
| | - Ananya Roy
- Department of Biological Sciences, Bose Institute, Kolkata, West Bengal, India
| | - Pallabi Sengupta
- Department of Medical Biochemistry and Biophysics, Kemihuset (K), Campus, Umeå, Umeå universitet, Umeå, Sweden
| | | |
Collapse
|
3
|
Luo Y, Živković ML, Wang J, Ryneš J, Foldynová-Trantírková S, Trantírek L, Verga D, Mergny JL. A sodium/potassium switch for G4-prone G/C-rich sequences. Nucleic Acids Res 2024; 52:448-461. [PMID: 37986223 PMCID: PMC10783510 DOI: 10.1093/nar/gkad1073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Revised: 10/19/2023] [Accepted: 11/03/2023] [Indexed: 11/22/2023] Open
Abstract
Metal ions are essential components for the survival of living organisms. For most species, intracellular and extracellular ionic conditions differ significantly. As G-quadruplexes (G4s) are ion-dependent structures, changes in the [Na+]/[K+] ratio may affect the folding of genomic G4s. More than 11000 putative G4 sequences in the human genome (hg19) contain at least two runs of three continuous cytosines, and these mixed G/C-rich sequences may form a quadruplex or a competing hairpin structure based on G-C base pairing. In this study, we examine how the [Na+]/[K+] ratio influences the structures of G/C-rich sequences. The natural G4 structure with a 9-nt long central loop, CEBwt, was chosen as a model sequence, and the loop bases were gradually replaced by cytosines. The series of CEB mutations revealed that the presence of cytosines in G4 loops does not prevent G4 folding or decrease G4 stability but increases the probability of forming a competing structure, either a hairpin or an intermolecular duplex. Slow conversion to the quadruplex in vitro (in a potassium-rich buffer) and cells was demonstrated by NMR. 'Shape-shifting' sequences may respond to [Na+]/[K+] changes with delayed kinetics.
Collapse
Affiliation(s)
- Yu Luo
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
| | - Martina Lenarčič Živković
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
- Slovenian NMR Centre, National Institute of Chemistry, SI-1000 Ljubljana, Slovenia
| | - Jiawei Wang
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Jan Ryneš
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | | | - Lukáš Trantírek
- Central European Institute of Technology, Masaryk University, 625 00 Brno, Czech Republic
| | - Daniela Verga
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France
| | - Jean-Louis Mergny
- Laboratoire d’Optique et Biosciences, Ecole Polytechnique, CNRS, Inserm, Institut Polytechnique de Paris, 91128 Palaiseau, France
| |
Collapse
|
4
|
Vannutelli A, Ouangraoua A, Perreault JP. Toward a Better Understanding of G4 Evolution in the 3 Living Kingdoms. Evol Bioinform Online 2023; 19:11769343231212075. [PMID: 38046653 PMCID: PMC10693206 DOI: 10.1177/11769343231212075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 10/18/2023] [Indexed: 12/05/2023] Open
Abstract
Background G-quadruplexes (G4s) are secondary structures in DNA and RNA that impact various cellular processes, such as transcription, splicing, and translation. Due to their numerous functions, G4s are involved in many diseases, making their study important. Yet, G4s evolution remains largely unknown, due to their low sequence similarity and the poor quality of their sequence alignments across several species. To address this, we designed a strategy that avoids direct G4s alignment to study G4s evolution in the 3 species kingdoms. We also explored the coevolution between RBPs and G4s. Methods We retrieved one-to-one orthologous genes from the Ensembl Compara database and computed groups of one-to-one orthologous genes. For each group, we aligned gene sequences and identified G4 families as groups of overlapping G4s in the alignment. We analyzed these G4 families using Count, a tool to infer feature evolution into a gene or a species tree. Additionally, we utilized these G4 families to predict G4s by homology. To establish a control dataset, we performed mono-, di- and tri-nucleotide shuffling. Results Only a few conserved G4s occur among all living kingdoms. In eukaryotes, G4s exhibit slight conservation among vertebrates, and few are conserved between plants. In archaea and bacteria, at most, only 2 G4s are common. The G4 homology-based prediction increases the number of conserved G4s in common ancestors. The coevolution between RNA-binding proteins and G4s was investigated and revealed a modest impact of RNA-binding proteins evolution on G4 evolution. However, the details of this relationship remain unclear. Conclusion Even if G4 evolution still eludes us, the present study provides key information to compute groups of homologous G4 and to reveal the evolution history of G4 families.
Collapse
Affiliation(s)
- Anaïs Vannutelli
- Département de biochimie et de génomique fonctionnelle, faculté de médecine et des sciences de la santé, pavillon de recherche appliquée sur le cancer, Université de Sherbrooke, Sherbrooke, QC, Canada
- Département d’informatique, faculté des sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Aïda Ouangraoua
- Département d’informatique, faculté des sciences, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Jean-Pierre Perreault
- Département de biochimie et de génomique fonctionnelle, faculté de médecine et des sciences de la santé, pavillon de recherche appliquée sur le cancer, Université de Sherbrooke, Sherbrooke, QC, Canada
| |
Collapse
|
5
|
Elimelech-Zohar K, Orenstein Y. An overview on nucleic-acid G-quadruplex prediction: from rule-based methods to deep neural networks. Brief Bioinform 2023:bbad252. [PMID: 37438149 DOI: 10.1093/bib/bbad252] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 05/11/2023] [Accepted: 06/18/2023] [Indexed: 07/14/2023] Open
Abstract
Nucleic-acid G-quadruplexes (G4s) play vital roles in many cellular processes. Due to their importance, researchers have developed experimental assays to measure nucleic-acid G4s in high throughput. The generated high-throughput datasets gave rise to unique opportunities to develop machine-learning-based methods, and in particular deep neural networks, to predict G4s in any given nucleic-acid sequence and any species. In this paper, we review the success stories of deep-neural-network applications for G4 prediction. We first cover the experimental technologies that generated the most comprehensive nucleic-acid G4 high-throughput datasets in recent years. We then review classic rule-based methods for G4 prediction. We proceed by reviewing the major machine-learning and deep-neural-network applications to nucleic-acid G4 datasets and report a novel comparison between them. Next, we present the interpretability techniques used on the trained neural networks to learn key molecular principles underlying nucleic-acid G4 folding. As a new result, we calculate the overlap between measured DNA and RNA G4s and compare the performance of DNA- and RNA-G4 predictors on RNA- and DNA-G4 datasets, respectively, to demonstrate the potential of transfer learning from DNA G4s to RNA G4s. Last, we conclude with open questions in the field of nucleic-acid G4 prediction and computational modeling.
Collapse
Affiliation(s)
| | - Yaron Orenstein
- Department of Computer Science, Bar-Ilan University, Ramat Gan, 5290002, Israel
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| |
Collapse
|
6
|
Monti L, Di Antonio M. G-Quadruplexes as Key Transcriptional Regulators in Neglected Trypanosomatid Parasites. Chembiochem 2023; 24:e202300265. [PMID: 37146230 PMCID: PMC10946822 DOI: 10.1002/cbic.202300265] [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: 04/01/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 05/07/2023]
Abstract
G-quadruplexes (G4s) are nucleic acid secondary structures that have been linked to the functional regulation of eukaryotic organisms. G4s have been extensively characterised in humans and emerging evidence suggests that they might also be biologically relevant for human pathogens. This indicates that G4s might represent a novel class of therapeutic targets for tackling infectious diseases. Bioinformatic studies revealed a high prevalence of putative quadruplex-forming sequences (PQSs) in the genome of protozoans, which highlights their potential roles in regulating vital processes of these parasites, including DNA transcription and replication. In this work, we focus on the neglected trypanosomatid parasites, Trypanosoma and Leishmania spp., which cause debilitating and deadly diseases across the poorest populations worldwide. We review three examples where G4-formation might be key to modulate transcriptional activity in trypanosomatids, providing an overview of experimental approaches that can be used to exploit the regulatory roles and relevance of these structures to fight parasitic infections.
Collapse
Affiliation(s)
- Ludovica Monti
- Chemistry Department, Imperial College LondonMolecular Sciences Research Hub82 Wood LaneW12 0BZLondonUK
| | - Marco Di Antonio
- Chemistry Department, Imperial College LondonMolecular Sciences Research Hub82 Wood LaneW12 0BZLondonUK
- The Francis Crick Institute1 Midland RoadNW1 1ATLondonUK
- The Institute of Chemical BiologyMolecular Sciences Research Hub82 Wood LaneW12 0BZLondonUK
| |
Collapse
|
7
|
Vijay Kumar MJ, Morales R, Tsvetkov AS. G-quadruplexes and associated proteins in aging and Alzheimer's disease. FRONTIERS IN AGING 2023; 4:1164057. [PMID: 37323535 PMCID: PMC10267416 DOI: 10.3389/fragi.2023.1164057] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Accepted: 05/17/2023] [Indexed: 06/17/2023]
Abstract
Aging is a prominent risk factor for many neurodegenerative disorders, such as Alzheimer's disease (AD). Alzheimer's disease is characterized by progressive cognitive decline, memory loss, and neuropsychiatric and behavioral symptoms, accounting for most of the reported dementia cases. This disease is now becoming a major challenge and burden on modern society, especially with the aging population. Over the last few decades, a significant understanding of the pathophysiology of AD has been gained by studying amyloid deposition, hyperphosphorylated tau, synaptic dysfunction, oxidative stress, calcium dysregulation, and neuroinflammation. This review focuses on the role of non-canonical secondary structures of DNA/RNA G-quadruplexes (G4s, G4-DNA, and G4-RNA), G4-binding proteins (G4BPs), and helicases, and their roles in aging and AD. Being critically important for cellular function, G4s are involved in the regulation of DNA and RNA processes, such as replication, transcription, translation, RNA localization, and degradation. Recent studies have also highlighted G4-DNA's roles in inducing DNA double-strand breaks that cause genomic instability and G4-RNA's participation in regulating stress granule formation. This review emphasizes the significance of G4s in aging processes and how their homeostatic imbalance may contribute to the pathophysiology of AD.
Collapse
Affiliation(s)
- M. J. Vijay Kumar
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
| | - Rodrigo Morales
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O’Higgins, Santiago, Chile
| | - Andrey S. Tsvetkov
- The Department of Neurology, The University of Texas McGovern Medical School at Houston, Houston, TX, United States
- The University of Texas Graduate School of Biomedical Sciences, Houston, TX, United States
- UTHealth Consortium on Aging, The University of Texas McGovern Medical School, Houston, TX, United States
| |
Collapse
|
8
|
Roy A, Basu D, Bose D, Dutta A, Dastidar SG, Chatterjee S. Identification and characterization of a flexile G-quadruplex in the distal promoter region of stemness gene REX1. Int J Biol Macromol 2023; 231:123263. [PMID: 36649868 DOI: 10.1016/j.ijbiomac.2023.123263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 01/15/2023]
Abstract
We have identified a parallel G-quadruplex (R1WT) in the distal promoter region (-821 base-pairs upstream of the TSS) of the pluripotent gene REX1. Through biophysical and biochemical approach, we have characterized the G-quadruplex (GQ) as a potential molecular switch that may control REX1 promoter activity to determine the transcriptional fate. Small- molecule interactive study of the monomeric form of R1WT (characterized as R1mut2) with TMPyP4 and BRACO-19 revealed GQ destabilization upon interaction with TMPyP4 and stabilization upon interaction with BRACO-19. This distinctive drug interactivity suggests the in cellulo R1WT to be a promising drug target. The endogenous existence of R1WT was confirmed by BG4 antibody derived chromatin immunoprecipitation experiment. Here in, we also report the endogenous interaction of GQ specific transcription factors (TFs) with R1WT region in the human chromatin of cancer cell. The wild-type G-quadruplex was found to interact with four important transcription factors, (i) specificity protein (Sp1) (ii) non-metastatic cell 2 (NM23-H2): a diphosphatase (iii) cellular nucleic acid binding protein (CNBP) and (iv) heterogenous nuclear ribonucleoprotein K (hnRNPK) in the REX1 promoter. In contrast, nucleolin protein (NCL) binding was found to be low to the said G-quadruplex. The flexibility of R1WT between folded and unfolded states, obtained from experimental and computational analysis strongly suggests R1WT to be an important gene regulatory element in the genome. It controls promoter DNA relaxation with the coordinated interaction of transcription factors, the deregulation of which seeds stemness characteristic in cancer cells for further metastatic progression.
Collapse
Affiliation(s)
- Ananya Roy
- Department of Biophysics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India
| | - Debadrita Basu
- Department of Bioinformatics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India
| | - Debopriya Bose
- Department of Biophysics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India
| | - Anindya Dutta
- Department of Biophysics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India
| | - Shubhra Ghosh Dastidar
- Department of Bioinformatics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India
| | - Subhrangsu Chatterjee
- Department of Biophysics, Bose Institute, EN-80 Sector V, Salt Lake, Unified Campus, Kolkata 700091, India.
| |
Collapse
|
9
|
Uyar B, Ozsamur NG, Celik FS, Ozbayram I, Erbas-Cakmak S. Downregulation of gene expression in hypoxic cancer cells by an activatable G-quadruplex stabiliser. Chem Commun (Camb) 2023; 59:2247-2250. [PMID: 36723070 DOI: 10.1039/d2cc06347f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In the research, the modulation of gene expression with a novel G-quadruplex stabiliser was analysed. Activation by the removal of bulky hypoxia-responsive substituent enhances G-quadruplex stabilisation. Hypoxic MCF7 cells incubated with the stabiliser displayed significant downregulation of oncogenes c-myc, bcl-2, and hif-1α. This study presents the first hypoxia-activatable G-quadruplex stabilization and transcriptional regulation.
Collapse
Affiliation(s)
- Busra Uyar
- Konya Food and Agriculture University, Department of Biotechnology, Konya 42080, Turkey.
| | - Nezahat Gokce Ozsamur
- Konya Food and Agriculture University, Department of Biotechnology, Konya 42080, Turkey.
| | - Fatma Secer Celik
- Konya Food and Agriculture University, Department of Biotechnology, Konya 42080, Turkey.
| | - Ilkyaz Ozbayram
- Konya Food and Agriculture University, Department of Biotechnology, Konya 42080, Turkey.
| | - Sundus Erbas-Cakmak
- Konya Food and Agriculture University, Department of Biotechnology, Konya 42080, Turkey. .,Konya Food and Agriculture University, Department of Molecular Biology and Genetics, Konya 42080, Turkey
| |
Collapse
|
10
|
Makova KD, Weissensteiner MH. Noncanonical DNA structures are drivers of genome evolution. Trends Genet 2023; 39:109-124. [PMID: 36604282 PMCID: PMC9877202 DOI: 10.1016/j.tig.2022.11.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 11/04/2022] [Accepted: 11/28/2022] [Indexed: 01/05/2023]
Abstract
In addition to the canonical right-handed double helix, other DNA structures, termed 'non-B DNA', can form in the genomes across the tree of life. Non-B DNA regulates multiple cellular processes, including replication and transcription, yet its presence is associated with elevated mutagenicity and genome instability. These discordant cellular roles fuel the enormous potential of non-B DNA to drive genomic and phenotypic evolution. Here we discuss recent studies establishing non-B DNA structures as novel functional elements subject to natural selection, affecting evolution of transposable elements (TEs), and specifying centromeres. By highlighting the contributions of non-B DNA to repeated evolution and adaptation to changing environments, we conclude that evolutionary analyses should include a perspective of not only DNA sequence, but also its structure.
Collapse
Affiliation(s)
- Kateryna D Makova
- Department of Biology, Penn State University, 310 Wartik Laboratory, University Park, PA 16802, USA.
| | | |
Collapse
|
11
|
Ruggiero E, Richter SN. Targeting G-quadruplexes to achieve antiviral activity. Bioorg Med Chem Lett 2023; 79:129085. [PMID: 36423824 PMCID: PMC9760570 DOI: 10.1016/j.bmcl.2022.129085] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 11/09/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022]
Abstract
With the emergence of new viruses in the human population and the fast mutation rates of existing viruses, new antiviral targets and compounds are needed. Most existing antiviral drugs are active against proteins of a handful of viruses. Most of these proteins in the end affect viral nucleic acid processing, but direct nucleic acid targeting is less represented due to the difficulty of selectively acting at the nucleic acid of interest. Recently, nucleic acids have been shown to fold in structures alternative to the classic double helix and Watson and Crick base-pairing. Among these non-canonical structures, G-quadruplexes (G4s) have attracted interest because of their key biological roles that are being discovered. Molecules able to selectively target G4s have been developed and since G4s have been investigated as targets in several human pathologies, including viral infections. Here, after briefly introducing viruses, G4s and the G4-binding molecules with antiviral properties, we comment on the mechanisms at the base of the antiviral activity reported for G4-binding molecules. Understanding how G4-ligands act in infected cells will possibly help designing and developing next-generation antiviral drugs.
Collapse
Affiliation(s)
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, Italy; Microbiology and Virology Unit, Padua University Hospital, Padua, Italy.
| |
Collapse
|
12
|
Xiang M, Li Y, Liu J, Shi J, Ge Y, Peng C, Bin Y, Wang Z, Wang L. G-Quadruplex Linked DNA Guides Selective Transfection into Nucleolin-Overexpressing Cancer Cells. Pharmaceutics 2022; 14:pharmaceutics14102247. [PMID: 36297681 PMCID: PMC9609445 DOI: 10.3390/pharmaceutics14102247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/29/2022] [Accepted: 10/13/2022] [Indexed: 11/16/2022] Open
Abstract
Gene therapy is a promising approach for treating tumors. Conventional approaches of DNA delivery depending on non-viral or viral vectors are unsatisfactory due to the concerns of biosafety and cell-targeting efficiency. The question how to deliver DNA into tumor cells efficiently and selectively is a major technological problem in tumor gene therapy. Here, we develop a vector-free gene transfer strategy to deliver genes effectively and selectively by taking advantage of targeting nucleolin. Nucleolin, a shuttle protein moving between cell membrane, cytoplasm and nuclei, is overexpressed in tumor cells. It has a natural ligand G-quadruplex (Gq). Gq-linked DNA (Gq-DNA) is likely to be internalized by ligand dependent uptake mechanisms independently of vectors after neutralizing negative charges of cell membrane by targeting nucleolin. This strategy is referred to as Gq-DNA transfection. Benefiting from its high affinity to nucleolin, Gq-DNA can be effectively delivered into nucleolin-positive tumor cells even nuclei. Gq-DNA transfection is characterized by low cytotoxicity, high efficiency, ease of synthesis, high stability in serum, direct access into nuclei, and specific nucleolin-positive tumor cell targeting.
Collapse
Affiliation(s)
- Mengxi Xiang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yongkui Li
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jia Liu
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jie Shi
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yizhi Ge
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Chen Peng
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yawen Bin
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Zheng Wang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Correspondence: (Z.W.); (L.W.)
| | - Lin Wang
- Research Center for Tissue Engineering and Regenerative Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Department of Clinical Laboratory, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Correspondence: (Z.W.); (L.W.)
| |
Collapse
|
13
|
Vannutelli A, Schell L, Perreault JP, Ouangraoua A. GAIA: G-quadruplexes in alive creature database. Nucleic Acids Res 2022; 51:D135-D140. [PMID: 35971612 PMCID: PMC9825426 DOI: 10.1093/nar/gkac657] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 07/08/2022] [Accepted: 08/08/2022] [Indexed: 01/29/2023] Open
Abstract
G-quadruplexes (G4) are 3D structures that are found in both DNA and RNA. Interest in this structure has grown over the past few years due to both its implication in diverse biological mechanisms and its potential use as a therapeutic target, to name two examples. G4s in humans have been widely studied; however, the level of their study in other species remains relatively minimal. That said, progress in this field has resulted in the prediction of G4s structures in various species, ranging from bacteria to eukaryotes. These predictions were analysed in a previous study which revealed that G4s are present in all living kingdoms. To date, eleven different databases have grouped the various G4s depending on either their structures, on the proteins that might bind them, or on their location in the various genomes. However, none of these databases contains information on their location in the transcriptome of many of the implicated species. The GAIA database was designed so as to make this data available online in a user-friendly manner. Through its web interface, users can query GAIA to filter G4s, which, we hope, will help the research in this field. GAIA is available at: https://gaia.cobius.usherbrooke.ca.
Collapse
Affiliation(s)
- Anaïs Vannutelli
- Department of Biochemistry and Functional Genomics, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, QC J1E 4K8, Canada,Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC J1K 2R1, Canada
| | | | - Jean-Pierre Perreault
- Correspondence may also be addressed to Jean-Pierre Perreault. Tel: +1 819 821 8000 (Ext 75310);
| | - Aïda Ouangraoua
- To whom correspondence should be addressed. Tel: +1 819 821 8000 (Ext 62014);
| |
Collapse
|
14
|
Vannutelli A, Perreault JP, Ouangraoua A. G-quadruplex occurrence and conservation: more than just a question of guanine–cytosine content. NAR Genom Bioinform 2022; 4:lqac010. [PMID: 35261973 PMCID: PMC8896161 DOI: 10.1093/nargab/lqac010] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 12/06/2021] [Accepted: 02/25/2022] [Indexed: 12/14/2022] Open
Abstract
G-quadruplexes are motifs found in DNA and RNA that can fold into tertiary structures. Until now, they have been studied experimentally mainly in humans and a few other species. Recently, predictions have been made with bacterial and archaeal genomes. Nevertheless, a global comparison of predicted G4s (pG4s) across and within the three living kingdoms has not been addressed. In this study, we aimed to predict G4s in genes and transcripts of all kingdoms of living organisms and investigated the differences in their distributions. The relation of the predictions with GC content was studied. It appears that GC content is not the only parameter impacting G4 predictions and abundance. The distribution of pG4 densities varies depending on the class of transcripts and the group of species. Indeed, we have observed that, in coding transcripts, there are more predicted G4s than expected for eukaryotes but not for archaea and bacteria, while in noncoding transcripts, there are as many or fewer predicted G4s in all species groups. We even noticed that some species with the same GC content presented different pG4 profiles. For instance, Leishmania major and Chlamydomonas reinhardtii both have 60% of GC content, but the former has a pG4 density of 0.07 and the latter 1.16.
Collapse
Affiliation(s)
- Anaïs Vannutelli
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
- Department of Biochemistry and Functional Genomics, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, QC J1E 4K8, Canada
| | - Jean-Pierre Perreault
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
| | - Aïda Ouangraoua
- Department of Computer Science, Faculté des sciences, Université de Sherbrooke, QC, J1K 2R1, Canada
| |
Collapse
|
15
|
Cantara A, Luo Y, Dobrovolná M, Bohalova N, Fojta M, Verga D, Guittat L, Cucchiarini A, Savrimoutou S, Häberli C, Guillon J, Keiser J, Brázda V, Mergny JL. G-quadruplexes in helminth parasites. Nucleic Acids Res 2022; 50:2719-2735. [PMID: 35234933 PMCID: PMC8934627 DOI: 10.1093/nar/gkac129] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 02/07/2022] [Accepted: 02/25/2022] [Indexed: 12/12/2022] Open
Abstract
Parasitic helminths infecting humans are highly prevalent infecting ∼2 billion people worldwide, causing inflammatory responses, malnutrition and anemia that are the primary cause of morbidity. In addition, helminth infections of cattle have a significant economic impact on livestock production, milk yield and fertility. The etiological agents of helminth infections are mainly Nematodes (roundworms) and Platyhelminths (flatworms). G-quadruplexes (G4) are unusual nucleic acid structures formed by G-rich sequences that can be recognized by specific G4 ligands. Here we used the G4Hunter Web Tool to identify and compare potential G4 sequences (PQS) in the nuclear and mitochondrial genomes of various helminths to identify G4 ligand targets. PQS are nonrandomly distributed in these genomes and often located in the proximity of genes. Unexpectedly, a Nematode, Ascaris lumbricoides, was found to be highly enriched in stable PQS. This species can tolerate high-stability G4 structures, which are not counter selected at all, in stark contrast to most other species. We experimentally confirmed G4 formation for sequences found in four different parasitic helminths. Small molecules able to selectively recognize G4 were found to bind to Schistosoma mansoni G4 motifs. Two of these ligands demonstrated potent activity both against larval and adult stages of this parasite.
Collapse
Affiliation(s)
- Alessio Cantara
- Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic
| | - Yu Luo
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France.,Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Michaela Dobrovolná
- Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 612 00 Brno, Czech Republic
| | - Natalia Bohalova
- Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic
| | - Miroslav Fojta
- Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic
| | - Daniela Verga
- CNRS UMR9187, INSERM U1196, Université Paris-Saclay, F-91405 Orsay, France.,CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, F-91405 Orsay, France
| | - Lionel Guittat
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau, France.,Université Sorbonne Paris Nord, UFR SMBH, Bobigny, France
| | - Anne Cucchiarini
- Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Solène Savrimoutou
- ARNA Laboratory, Université de Bordeaux, INSERM U1212, CNRS UMR 5320, UFR des Sciences Pharmaceutiques, Bordeaux, France
| | - Cécile Häberli
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Jean Guillon
- ARNA Laboratory, Université de Bordeaux, INSERM U1212, CNRS UMR 5320, UFR des Sciences Pharmaceutiques, Bordeaux, France
| | - Jennifer Keiser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | - Václav Brázda
- Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,Faculty of Chemistry, Brno University of Technology, Purkyňova 118, 612 00 Brno, Czech Republic
| | - Jean Louis Mergny
- Institute of Biophysics, Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic.,Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128 Palaiseau, France
| |
Collapse
|
16
|
Stefos GC, Theodorou G, Politis I. Genomic landscape, polymorphism and possible LINE-associated delivery of G-quadruplex motifs in the bovine genes. Genomics 2022; 114:110272. [PMID: 35092818 DOI: 10.1016/j.ygeno.2022.110272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 01/12/2022] [Accepted: 01/18/2022] [Indexed: 12/29/2022]
Abstract
G-Quadruplex structures are non-B DNA structures that occur in regions carrying short runs of guanines. They are implicated in several biological processes including transcription, translation, replication and telomere maintenance as well as in several pathological conditions like cancer and thus they have gained the attention of the scientific community. The rise of the -omics era significantly affected the G-quadruplex research and the genome-wide characterization of G-Quadruplexes has been rendered a necessary first step towards applying genomics approaches for their study. While in human and several model organisms there is a considerable number of works studying genome-wide the DNA motifs with potential to form G-quadruplexes (G4-motifs), there is a total absence of any similar studies regarding livestock animals. The objectives of the present study were to provide a detailed characterization of the bovine genic G4-motifs' distribution and properties and to suggest a possible mechanism for the delivery of G4 motifs in the genes. Our data indicate that the distribution of G4-motifs within bovine genes and the annotation of said genes to Gene Ontology terms are similar to what is already shown for other organisms. By investigating their structural characteristics and polymorphism, it is obvious that the overall stability of the putative quadruplex structures is in line with the current notion in the G4 field. Similarly to human, the bovine G4-motifs are overrepresented in specific LINE repeat elements, the L1_BTs in the case of cattle. We highlight the potential role of these elements as vehicles for delivery of G4 motifs in the introns of the bovine genes. Lastly, it seems that a basis exists for connecting traits of agricultural importance to the genetic variation of G4 motifs, thus, the value of cattle as an interesting new model organism for G4-related genetic studies might be worth to be investigated.
Collapse
Affiliation(s)
- Georgios C Stefos
- Agricultural University of Athens, Department of Animal Science, Laboratory of Animal Breeding & Husbandry, 75 Iera Odos, 118 55, Athens, Greece.
| | - Georgios Theodorou
- Agricultural University of Athens, Department of Animal Science, Laboratory of Animal Breeding & Husbandry, 75 Iera Odos, 118 55, Athens, Greece.
| | - Ioannis Politis
- Agricultural University of Athens, Department of Animal Science, Laboratory of Animal Breeding & Husbandry, 75 Iera Odos, 118 55, Athens, Greece
| |
Collapse
|
17
|
Cebrián R, Belmonte-Reche E, Pirota V, de Jong A, Morales JC, Freccero M, Doria F, Kuipers OP. G-Quadruplex DNA as a Target in Pathogenic Bacteria: Efficacy of an Extended Naphthalene Diimide Ligand and Its Mode of Action. J Med Chem 2021; 65:4752-4766. [PMID: 34928608 PMCID: PMC8958502 DOI: 10.1021/acs.jmedchem.1c01905] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Guanidine DNA quadruplex
(G4-DNA) structures convey a distinctive
layer of epigenetic information that is critical for regulating key
biological activities and processes as transcription, replication,
and repair in living cells. The information regarding their role and
use as therapeutic drug targets in bacteria is still scarce. Here,
we tested the biological activity of a G4-DNA ligand library, based
on the naphthalene diimide (NDI) pharmacophore, against both Gram-positive
and Gram-negative bacteria. For the best compound identified, NDI-10, a different action mechanism was described for Gram-positive
or negative bacteria. This asymmetric activity profile could be related
to the different prevalence of putative G4-DNA structures in each
group, the influence that they can exert on gene expression, and the
different roles of the G4 structures in these bacteria, which seem
to promote transcription in Gram-positive bacteria and repress transcription
in Gram-negatives.
Collapse
Affiliation(s)
- Rubén Cebrián
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747AG Groningen, The Netherlands
| | - Efres Belmonte-Reche
- Advanced (magnetic) Theranostic Nanostructures Lab, International Iberian Nanotechnology Laboratory, Nanomedicine unit, Avenida Mestre José Veiga, s/n 4715-310 Braga, Portugal
| | - Valentina Pirota
- Department of Chemistry, University of Pavia, via Taramelli 10, I-27100 Pavia (PV), Italy
| | - Anne de Jong
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747AG Groningen, The Netherlands
| | - Juan Carlos Morales
- Department of Biochemistry and Molecular Pharmacology, Instituto de Parasitología y Biomedicina, CSIC, PTS Granada, Avda. del Conocimiento, 17, 18016 Armilla, Granada, Spain
| | - Mauro Freccero
- Department of Chemistry, University of Pavia, via Taramelli 10, I-27100 Pavia (PV), Italy
| | - Filippo Doria
- Department of Chemistry, University of Pavia, via Taramelli 10, I-27100 Pavia (PV), Italy
| | - Oscar P Kuipers
- Department of Molecular Genetics, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747AG Groningen, The Netherlands
| |
Collapse
|
18
|
Dickerhoff J, Brundridge N, McLuckey SA, Yang D. Berberine Molecular Recognition of the Parallel MYC G-Quadruplex in Solution. J Med Chem 2021; 64:16205-16212. [PMID: 34677968 PMCID: PMC8614230 DOI: 10.1021/acs.jmedchem.1c01508] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The medicinal natural product berberine is one of the most actively studied and pursued G-quadruplex (G4)-ligands. The major G-quadruplex formed in the promoter region of the MYC oncogene (MycG4) is an attractive drug target and a prominent example and model structure for parallel G-quadruplexes. G4-targeted berberine derivatives have been actively developed; however, the analogue design was based on a previous crystal structure in which berberine binds as a dimer to a parallel G-quadruplex. Herein, we show that in solution, the binding mode and stoichiometry of berberine are substantially different from the crystal structure: berberine binds as a monomer to MycG4 using a base-recruitment mechanism with a reversed orientation in that the positively charged convex side is actually positioned above the tetrad center. Our structure provides a physiologically relevant basis for the future structure-based rational design of G4-targeted berberine derivatives, and this study demonstrates that it is crucial to validate the ligand-DNA interactions.
Collapse
Affiliation(s)
- Jonathan Dickerhoff
- Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 W Stadium Avenue, West Lafayette, Indiana 47904, United States
| | - Nicole Brundridge
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
| | - Scott A McLuckey
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
| | - Danzhou Yang
- Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 W Stadium Avenue, West Lafayette, Indiana 47904, United States
- Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907, United States
- Purdue Center for Cancer Research, and Purdue Institute for Drug Discovery, West Lafayette, Indiana 47907, United States
| |
Collapse
|
19
|
Brázda V, Bohálová N, Bowater RP. New telomere to telomere assembly of human chromosome 8 reveals a previous underestimation of G-quadruplex forming sequences and inverted repeats. Gene 2021; 810:146058. [PMID: 34737002 DOI: 10.1016/j.gene.2021.146058] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/14/2021] [Accepted: 10/29/2021] [Indexed: 11/04/2022]
Abstract
Taking advantage of evolving and improving sequencing methods, human chromosome 8 is now available as a gapless, end-to-end assembly. Thanks to advances in long-read sequencing technologies, its centromere, telomeres, duplicated gene families and repeat-rich regions are now fully sequenced. We were interested to assess if the new assembly altered our understanding of the potential impact of non-B DNA structures within this completed chromosome sequence. It has been shown that non-B secondary structures, such as G-quadruplexes, hairpins and cruciforms, have important regulatory functions and potential as targeted therapeutics. Therefore, we analysed the presence of putative G-quadruplex forming sequences and inverted repeats in the current human reference genome (GRCh38) and in the new end-to-end assembly of chromosome 8. The comparison revealed that the new assembly contains significantly more inverted repeats and G-quadruplex forming sequences compared to the current reference sequence. This observation can be explained by improved accuracy of the new sequencing methods, particularly in regions that contain extensive repeats of bases, as is preferred by many non-B DNA structures. These results show a significant underestimation of the prevalence of non-B DNA secondary structure in previous assembly versions of the human genome and point to their importance being not fully appreciated. We anticipate that similar observations will occur as the improved sequencing technologies fill in gaps across the genomes of humans and other organisms.
Collapse
Affiliation(s)
- Václav Brázda
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 612 65, Czech Republic.
| | - Natália Bohálová
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, Brno 612 65, Czech Republic; Department of Experimental Biology, Faculty of Science, Masaryk University, Kamenice 5, Brno 62500, Czech Republic
| | - Richard P Bowater
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom.
| |
Collapse
|
20
|
Evaluating Molecular Docking Software for Small Molecule Binding to G-Quadruplex DNA. Int J Mol Sci 2021; 22:ijms221910801. [PMID: 34639142 PMCID: PMC8509811 DOI: 10.3390/ijms221910801] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 01/08/2023] Open
Abstract
G-quadruplexes are four-stranded nucleic acid secondary structures of biological significance and have emerged as an attractive drug target. The G4 formed in the MYC promoter (MycG4) is one of the most studied small-molecule targets, and a model system for parallel structures that are prevalent in promoter DNA G4s and RNA G4s. Molecular docking has become an essential tool in structure-based drug discovery for protein targets, and is also increasingly applied to G4 DNA. However, DNA, and in particular G4, binding sites differ significantly from protein targets. Here we perform the first systematic evaluation of four commonly used docking programs (AutoDock Vina, DOCK 6, Glide, and RxDock) for G4 DNA-ligand binding pose prediction using four small molecules whose complex structures with the MycG4 have been experimentally determined in solution. The results indicate that there are considerable differences in the performance of the docking programs and that DOCK 6 with GB/SA rescoring performs better than the other programs. We found that docking accuracy is mainly limited by the scoring functions. The study shows that current docking programs should be used with caution to predict G4 DNA-small molecule binding modes.
Collapse
|
21
|
Seimiya H, Nagasawa K, Shin-Ya K. Chemical targeting of G-quadruplexes in telomeres and beyond for molecular cancer therapeutics. J Antibiot (Tokyo) 2021; 74:617-628. [PMID: 34285374 DOI: 10.1038/s41429-021-00454-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/29/2021] [Accepted: 06/03/2021] [Indexed: 02/06/2023]
Abstract
G-quadruplexes (G4s) are higher-order structures formed by guanine-rich sequences of nucleic acids, such as the telomeric 5'-TTAGGG-3'/5'-UUAGGG-3' repeats and those in gene regulatory regions. G4s regulate various biological events, including replication, transcription, and translation. Imbalanced G4 dynamics is associated with diseases, such as cancer and neurodegenerative diseases. Telomestatin is a natural macrocyclic compound derived from Streptomyces anulatus 3533-SV4. It interacts with the guanine quartet via π-π stacking and potently stabilizes G4. Because G4 stabilization at the telomeric repeat inhibits the telomere-synthesizing enzyme telomerase, telomestatin was originally identified as a telomerase inhibitor. Whereas non-toxic doses of telomestatin induce gradual shortening of telomeres and eventual crisis in human cancer cells, higher doses trigger prompt replication stress and DNA damage responses, resulting in acute cell death. Suppression of the transcription and translation of G4-containing genes is also implicated in the anticancer effects of telomestatin. Because telomestatin is rare, labile, and insoluble, synthetic oxazole telomestatin derivatives have been developed and verified for their therapeutic efficacies in preclinical cancer models. Furthermore, a variety of G4-stabilizing compounds have been reported as promising seeds for molecular cancer therapeutics. To improve the design of future clinical studies, it will be important to identify predictive biomarkers of drug efficacy.
Collapse
Affiliation(s)
- Hiroyuki Seimiya
- Division of Molecular Biotherapy, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Tokyo, Japan.
| | - Kazuo Nagasawa
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Kazuo Shin-Ya
- National Institute of Advanced Industrial Science and Technology, Tokyo, Japan.,Technology Research Association for Next Generation Natural Products Chemistry, Tokyo, Japan
| |
Collapse
|
22
|
Li Z, Qian SH, Wang F, Mohamed HI, Yang G, Chen ZX, Wei D. G-quadruplexes in genomes of viruses infecting eukaryotes or prokaryotes are under different selection pressures from hosts. J Genet Genomics 2021; 49:20-29. [PMID: 34601118 DOI: 10.1016/j.jgg.2021.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 08/18/2021] [Accepted: 08/18/2021] [Indexed: 12/12/2022]
Abstract
G-quadruplexes in viral genomes can be applied as the targets of antiviral therapies, which has attracted wide interest. However, it is still not clear whether the pervasive number of such elements in the viral world is the result of natural selection for functionality. In this study, we identified putative quadruplex-forming sequences (PQSs) across the known viral genomes and analyzed the abundance, structural stability, and conservation of viral PQSs. A Viral Putative G-quadruplex Database (ViPGD,http://jsjds.hzau.edu.cn/MBPC/ViPGD/index.php/home/index) was constructed to collect the details of each viral PQS, which provides guidance for selecting the desirable PQS. The PQS with two putative G-tetrads (G2-PQS) was significantly enriched in both eukaryotic viruses and prokaryotic viruses, while the PQSs with three putative G-tetrads (G3-PQS) were only enriched in eukaryotic viruses and depleted in prokaryotic viruses. The structural stability of PQSs in prokaryotic viruses was significantly lower than that in eukaryotic viruses. Conservation analysis showed that the G2-PQS, instead of G3-PQS, was highly conserved within the genus. This suggested that the G2-quadruplex might play an important role in viral biology, and the difference in the occurrence of G-quadruplex between eukaryotic viruses and prokaryotic viruses may result from the different selection pressures from hosts.
Collapse
Affiliation(s)
- Zhen Li
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan 430070, China; College of Science, Huazhong Agricultural University, Wuhan 430070, China
| | - Sheng Hu Qian
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan 430070, China; College of Biomedicine and Health, Huazhong Agricultural University, Wuhan 430070, China
| | - Fan Wang
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, China; International joint Research Center for Intelligent Biosensor Technology and Health, Central China Normal University, Wuhan 430079, China
| | - Hany I Mohamed
- Chemistry Department, Faculty of Science, Benha University, Benha 13518, Egypt
| | - Guangfu Yang
- Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, China; International joint Research Center for Intelligent Biosensor Technology and Health, Central China Normal University, Wuhan 430079, China.
| | - Zhen-Xia Chen
- Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan 430070, China; College of Biomedicine and Health, Huazhong Agricultural University, Wuhan 430070, China; Hubei Key Laboratory of Agricultural Bioinformatics, College of Life Science and Technology, Huazhong Agricultural University, Wuhan 430070, China; Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen 518124, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China.
| | - Dengguo Wei
- State Key Laboratory of Agricultural Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan 430070, China; Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan 430070, China; National Reference Laboratory of Veterinary Drug Residues (HZAU) and MAO Key Laboratory for Detection of Veterinary Drug Residues, Huazhong Agricultural University, Wuhan, Hubei, 430070, China.
| |
Collapse
|
23
|
G-Quadruplex in Gene Encoding Large Subunit of Plant RNA Polymerase II: A Billion-Year-Old Story. Int J Mol Sci 2021; 22:ijms22147381. [PMID: 34299001 PMCID: PMC8306923 DOI: 10.3390/ijms22147381] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/24/2021] [Accepted: 07/05/2021] [Indexed: 12/12/2022] Open
Abstract
G-quadruplexes have long been perceived as rare and physiologically unimportant nucleic acid structures. However, several studies have revealed their importance in molecular processes, suggesting their possible role in replication and gene expression regulation. Pathways involving G-quadruplexes are intensively studied, especially in the context of human diseases, while their involvement in gene expression regulation in plants remains largely unexplored. Here, we conducted a bioinformatic study and performed a complex circular dichroism measurement to identify a stable G-quadruplex in the gene RPB1, coding for the RNA polymerase II large subunit. We found that this G-quadruplex-forming locus is highly evolutionarily conserved amongst plants sensu lato (Archaeplastida) that share a common ancestor more than one billion years old. Finally, we discussed a new hypothesis regarding G-quadruplexes interacting with UV light in plants to potentially form an additional layer of the regulatory network.
Collapse
|
24
|
Dickerhoff J, Dai J, Yang D. Structural recognition of the MYC promoter G-quadruplex by a quinoline derivative: insights into molecular targeting of parallel G-quadruplexes. Nucleic Acids Res 2021; 49:5905-5915. [PMID: 33978746 PMCID: PMC8191789 DOI: 10.1093/nar/gkab330] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/11/2021] [Accepted: 04/22/2021] [Indexed: 01/21/2023] Open
Abstract
DNA G-Quadruplexes (G4s) formed in oncogene promoters regulate transcription. The oncogene MYC promoter G4 (MycG4) is the most prevalent G4 in human cancers. However, the most studied MycG4 sequence bears a mutated 3′-residue crucial for ligand recognition. Here, we report a new drug-like small molecule PEQ without a large aromatic moiety that specifically binds MycG4. We determined the NMR solution structures of the wild-type MycG4 and its 2:1 PEQ complex, as well as the structure of the 2:1 PEQ complex of the widely used mutant MycG4. Comparison of the two complex structures demonstrates specific molecular recognition of MycG4 and shows the clear effect of the critical 3′-mutation on the drug binding interface. We performed a systematic analysis of the four available complex structures involving the same mutant MycG4, which can be considered a model system for parallel G4s, and revealed for the first time that the flexible flanking residues are recruited in a conserved and sequence-specific way, as well as unused potential for selective ligand-G4 hydrogen-bond interactions. Our results provide the true molecular basis for MycG4-targeting drugs and new critical insights into future rational design of drugs targeting MycG4 and parallel G4s that are prevalent in promoter and RNA G4s.
Collapse
Affiliation(s)
- Jonathan Dickerhoff
- Purdue University, College of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, 575 W Stadium Ave., West Lafayette, IN 47907, USA
| | - Jixun Dai
- College of Pharmacy, The University of Arizona, Tucson, AZ 85721, USA
| | - Danzhou Yang
- Purdue University, College of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, 575 W Stadium Ave., West Lafayette, IN 47907, USA.,Purdue University Center for Cancer Research, 201 S University St, West Lafayette, IN 47906, USA.,Purdue University, Department of Chemistry, West Lafayette, IN, USA.,Purdue Institute for Drug Discovery, West Lafayette, IN, USA
| |
Collapse
|
25
|
Wang W, Klein KN, Proesmans K, Yang H, Marchal C, Zhu X, Borrman T, Hastie A, Weng Z, Bechhoefer J, Chen CL, Gilbert DM, Rhind N. Genome-wide mapping of human DNA replication by optical replication mapping supports a stochastic model of eukaryotic replication. Mol Cell 2021; 81:2975-2988.e6. [PMID: 34157308 DOI: 10.1016/j.molcel.2021.05.024] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 03/08/2021] [Accepted: 05/20/2021] [Indexed: 12/27/2022]
Abstract
The heterogeneous nature of eukaryotic replication kinetics and the low efficiency of individual initiation sites make mapping the location and timing of replication initiation in human cells difficult. To address this challenge, we have developed optical replication mapping (ORM), a high-throughput single-molecule approach, and used it to map early-initiation events in human cells. The single-molecule nature of our data and a total of >2,500-fold coverage of the human genome on 27 million fibers averaging ∼300 kb in length allow us to identify initiation sites and their firing probability with high confidence. We find that the distribution of human replication initiation is consistent with inefficient, stochastic activation of heterogeneously distributed potential initiation complexes enriched in accessible chromatin. These observations are consistent with stochastic models of initiation-timing regulation and suggest that stochastic regulation of replication kinetics is a fundamental feature of eukaryotic replication, conserved from yeast to humans.
Collapse
Affiliation(s)
- Weitao Wang
- Institut Curie, PSL Research University, CNRS UMR 3244, Paris 75005, France
| | - Kyle N Klein
- Florida State University, Department of Biological Science, Tallahassee, FL 32306, USA
| | - Karel Proesmans
- Simon Fraser University, Department of Physics, Burnaby, BC V5A 1S6, Canada
| | - Hongbo Yang
- Northwestern University, Feinberg School of Medicine, Department of Biochemistry and Molecular Genetics, Chicago, IL 60208, USA
| | - Claire Marchal
- Florida State University, Department of Biological Science, Tallahassee, FL 32306, USA
| | - Xiaopeng Zhu
- Carnegie Mellon University, Computational Biology Department, Pittsburgh, PA 15213, USA
| | - Tyler Borrman
- University of Massachusetts Medical School, Program in Bioinformatics and Integrated Biology, Worcester, MA 01605, USA
| | | | - Zhiping Weng
- University of Massachusetts Medical School, Program in Bioinformatics and Integrated Biology, Worcester, MA 01605, USA
| | - John Bechhoefer
- Simon Fraser University, Department of Physics, Burnaby, BC V5A 1S6, Canada.
| | - Chun-Long Chen
- Institut Curie, PSL Research University, CNRS UMR 3244, Paris 75005, France; Sorbonne University, Paris 75005, France.
| | - David M Gilbert
- Florida State University, Department of Biological Science, Tallahassee, FL 32306, USA.
| | - Nicholas Rhind
- University of Massachusetts Medical School, Department of Biochemistry and Molecular Pharmacology, Worcester, MA 01605, USA.
| |
Collapse
|
26
|
Single-molecule imaging reveals replication fork coupled formation of G-quadruplex structures hinders local replication stress signaling. Nat Commun 2021; 12:2525. [PMID: 33953191 PMCID: PMC8099879 DOI: 10.1038/s41467-021-22830-9] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 03/30/2021] [Indexed: 12/19/2022] Open
Abstract
Guanine-rich DNA sequences occur throughout the human genome and can transiently form G-quadruplex (G4) structures that may obstruct DNA replication, leading to genomic instability. Here, we apply multi-color single-molecule localization microscopy (SMLM) coupled with robust data-mining algorithms to quantitatively visualize replication fork (RF)-coupled formation and spatial-association of endogenous G4s. Using this data, we investigate the effects of G4s on replisome dynamics and organization. We show that a small fraction of active replication forks spontaneously form G4s at newly unwound DNA immediately behind the MCM helicase and before nascent DNA synthesis. These G4s locally perturb replisome dynamics and organization by reducing DNA synthesis and limiting the binding of the single-strand DNA-binding protein RPA. We find that the resolution of RF-coupled G4s is mediated by an interplay between RPA and the FANCJ helicase. FANCJ deficiency leads to G4 accumulation, DNA damage at G4-associated replication forks, and silencing of the RPA-mediated replication stress response. Our study provides first-hand evidence of the intrinsic, RF-coupled formation of G4 structures, offering unique mechanistic insights into the interference and regulation of stable G4s at replication forks and their effect on RPA-associated fork signaling and genomic instability.
Collapse
|
27
|
Kosiol N, Juranek S, Brossart P, Heine A, Paeschke K. G-quadruplexes: a promising target for cancer therapy. Mol Cancer 2021; 20:40. [PMID: 33632214 PMCID: PMC7905668 DOI: 10.1186/s12943-021-01328-4] [Citation(s) in RCA: 215] [Impact Index Per Article: 71.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/01/2021] [Indexed: 12/13/2022] Open
Abstract
DNA and RNA can fold into a variety of alternative conformations. In recent years, a particular nucleic acid structure was discussed to play a role in malignant transformation and cancer development. This structure is called a G-quadruplex (G4). G4 structure formation can drive genome instability by creating mutations, deletions and stimulating recombination events. The importance of G4 structures in the characterization of malignant cells was currently demonstrated in breast cancer samples. In this analysis a correlation between G4 structure formation and an increased intratumor heterogeneity was identified. This suggests that G4 structures might allow breast cancer stratification and supports the identification of new personalized treatment options. Because of the stability of G4 structures and their presence within most human oncogenic promoters and at telomeres, G4 structures are currently tested as a therapeutic target to downregulate transcription or to block telomere elongation in cancer cells. To date, different chemical molecules (G4 ligands) have been developed that aim to target G4 structures. In this review we discuss and compare G4 function and relevance for therapeutic approaches and their impact on cancer development for three cancer entities, which differ significantly in their amount and type of mutations: pancreatic cancer, leukemia and malignant melanoma. G4 structures might present a promising new strategy to individually target tumor cells and could support personalized treatment approaches in the future.
Collapse
Affiliation(s)
- Nils Kosiol
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, 53127, Bonn, Germany
| | - Stefan Juranek
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, 53127, Bonn, Germany
| | - Peter Brossart
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, 53127, Bonn, Germany
| | - Annkristin Heine
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, 53127, Bonn, Germany
| | - Katrin Paeschke
- Department of Oncology, Hematology, Rheumatology and Immune-Oncology, University Hospital Bonn, 53127, Bonn, Germany.
| |
Collapse
|
28
|
Edwards AD, Marecki JC, Byrd AK, Gao J, Raney K. G-Quadruplex loops regulate PARP-1 enzymatic activation. Nucleic Acids Res 2021; 49:416-431. [PMID: 33313902 PMCID: PMC7797039 DOI: 10.1093/nar/gkaa1172] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 11/14/2020] [Accepted: 11/17/2020] [Indexed: 12/31/2022] Open
Abstract
G-Quadruplexes are non-B form DNA structures present at regulatory regions in the genome, such as promoters of proto-oncogenes and telomeres. The prominence in such sites suggests G-quadruplexes serve an important regulatory role in the cell. Indeed, oxidized G-quadruplexes found at regulatory sites are regarded as epigenetic elements and are associated with an interlinking of DNA repair and transcription. PARP-1 binds damaged DNA and non-B form DNA, where it covalently modifies repair enzymes or chromatin-associated proteins respectively with poly(ADP-ribose) (PAR). PAR serves as a signal in regulation of transcription, chromatin remodeling, and DNA repair. PARP-1 is known to bind G-quadruplexes with stimulation of enzymatic activity. We show that PARP-1 binds several G-quadruplex structures with nanomolar affinities, but only a subset promote PARP-1 activity. The G-quadruplex forming sequence found in the proto-oncogene c-KIT promoter stimulates enzymatic activity of PARP-1. The loop-forming characteristics of the c-KIT G-quadruplex sequence regulate PARP-1 catalytic activity, whereas eliminating these loop features reduces PARP-1 activity. Oxidized G-quadruplexes that have been suggested to form unique, looped structures stimulate PARP-1 activity. Our results support a functional interaction between PARP-1 and G-quadruplexes. PARP-1 enzymatic activation by G-quadruplexes is dependent on the loop features and the presence of oxidative damage.
Collapse
Affiliation(s)
- Andrea D Edwards
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - John C Marecki
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Alicia K Byrd
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Jun Gao
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Kevin D Raney
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
- Winthrop P. Rockefeller Cancer Institute, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| |
Collapse
|
29
|
Miglietta G, Russo M, Capranico G. G-quadruplex-R-loop interactions and the mechanism of anticancer G-quadruplex binders. Nucleic Acids Res 2020; 48:11942-11957. [PMID: 33137181 PMCID: PMC7708042 DOI: 10.1093/nar/gkaa944] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 10/05/2020] [Accepted: 10/08/2020] [Indexed: 12/17/2022] Open
Abstract
Genomic DNA and cellular RNAs can form a variety of non-B secondary structures, including G-quadruplex (G4) and R-loops. G4s are constituted by stacked guanine tetrads held together by Hoogsteen hydrogen bonds and can form at key regulatory sites of eukaryote genomes and transcripts, including gene promoters, untranslated exon regions and telomeres. R-loops are 3-stranded structures wherein the two strands of a DNA duplex are melted and one of them is annealed to an RNA. Specific G4 binders are intensively investigated to discover new effective anticancer drugs based on a common rationale, i.e.: the selective inhibition of oncogene expression or specific impairment of telomere maintenance. However, despite the high number of known G4 binders, such a selective molecular activity has not been fully established and several published data point to a different mode of action. We will review published data that address the close structural interplay between G4s and R-loops in vitro and in vivo, and how these interactions can have functional consequences in relation to G4 binder activity. We propose that R-loops can play a previously-underestimated role in G4 binder action, in relation to DNA damage induction, telomere maintenance, genome and epigenome instability and alterations of gene expression programs.
Collapse
Affiliation(s)
- Giulia Miglietta
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126 Bologna, Italy
| | - Marco Russo
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126 Bologna, Italy
| | - Giovanni Capranico
- Department of Pharmacy and Biotechnology, Alma Mater Studiorum University of Bologna, via Selmi 3, 40126 Bologna, Italy
| |
Collapse
|
30
|
A two-quartet G-quadruplex topology of human KIT2 is conformationally selected by a perylene derivative. Biochimie 2020; 179:77-84. [DOI: 10.1016/j.biochi.2020.09.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/11/2020] [Accepted: 09/14/2020] [Indexed: 12/19/2022]
|
31
|
Obi I, Rentoft M, Singh V, Jamroskovic J, Chand K, Chorell E, Westerlund F, Sabouri N. Stabilization of G-quadruplex DNA structures in Schizosaccharomyces pombe causes single-strand DNA lesions and impedes DNA replication. Nucleic Acids Res 2020; 48:10998-11015. [PMID: 33045725 PMCID: PMC7641769 DOI: 10.1093/nar/gkaa820] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 09/09/2020] [Accepted: 09/17/2020] [Indexed: 12/30/2022] Open
Abstract
G-quadruplex (G4) structures are stable non-canonical DNA structures that are implicated in the regulation of many cellular pathways. We show here that the G4-stabilizing compound PhenDC3 causes growth defects in Schizosaccharomyces pombe cells, especially during S-phase in synchronized cultures. By visualizing individual DNA molecules, we observed shorter DNA fragments of newly replicated DNA in the PhenDC3-treated cells, suggesting that PhenDC3 impedes replication fork progression. Furthermore, a novel single DNA molecule damage assay revealed increased single-strand DNA lesions in the PhenDC3-treated cells. Moreover, chromatin immunoprecipitation showed enrichment of the leading-strand DNA polymerase at sites of predicted G4 structures, suggesting that these structures impede DNA replication. We tested a subset of these sites and showed that they form G4 structures, that they stall DNA synthesis in vitro and that they can be resolved by the breast cancer-associated Pif1 family helicases. Our results thus suggest that G4 structures occur in S. pombe and that stabilized/unresolved G4 structures are obstacles for the replication machinery. The increased levels of DNA damage might further highlight the association of the human Pif1 helicase with familial breast cancer and the onset of other human diseases connected to unresolved G4 structures.
Collapse
Affiliation(s)
- Ikenna Obi
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Matilda Rentoft
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Vandana Singh
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Jan Jamroskovic
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Karam Chand
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Erik Chorell
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden
| | - Fredrik Westerlund
- Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Nasim Sabouri
- Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| |
Collapse
|
32
|
Chalikian TV, Liu L, Macgregor RB. Duplex-tetraplex equilibria in guanine- and cytosine-rich DNA. Biophys Chem 2020; 267:106473. [PMID: 33031980 DOI: 10.1016/j.bpc.2020.106473] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 09/03/2020] [Indexed: 02/07/2023]
Abstract
Noncanonical four-stranded DNA structures, including G-quadruplexes and i-motifs, have been discovered in the cell and are implicated in a variety of genomic regulatory functions. The tendency of a specific guanine- and cytosine-rich region of genomic DNA to adopt a four-stranded conformation depends on its ability to overcome the constraints of duplex base-pairing by undergoing consecutive duplex-to-coil and coil-to-tetraplex transitions. The latter ability is determined by the balance between the free energies of participating ordered and disordered structures. In this review, we present an overview of the literature on the stability of G-quadruplex and i-motif structures and discuss the extent of duplex-tetraplex competition as a function of the sequence context of the DNA and environmental conditions including temperature, pH, salt, molecular crowding, and the presence of G-quadruplex-binding ligands. We outline how the results of in vitro studies can be expanded to understanding duplex-tetraplex equilibria in vivo.
Collapse
Affiliation(s)
- Tigran V Chalikian
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada.
| | - Lutan Liu
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada
| | - Robert B Macgregor
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario M5S 3M2, Canada
| |
Collapse
|
33
|
Bednářová K, Vorlíčková M, Renčiuk D. Diversity of Parallel Guanine Quadruplexes Induced by Guanine Substitutions. Int J Mol Sci 2020; 21:E6123. [PMID: 32854410 PMCID: PMC7503932 DOI: 10.3390/ijms21176123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/21/2020] [Accepted: 08/22/2020] [Indexed: 01/17/2023] Open
Abstract
Recently, we reported an inhibitory effect of guanine substitutions on the conformational switch from antiparallel to parallel quadruplexes (G4) induced by dehydrating agents. As a possible cause, we proposed a difference in the sensitivity of parallel and antiparallel quadruplexes to the guanine substitutions in the resulting thermodynamic stability. Reports on the influence of guanine substitutions on the biophysical properties of intramolecular parallel quadruplexes are rare. Moreover, such reports are often complicated by the multimerisation tendencies of parallel quadruplexes. To address this incomplete knowledge, we employed circular dichroism spectroscopy (CD), both as stopped-flow-assisted fast kinetics measurements and end-point measurements, accompanied by thermodynamic analyses, based on UV absorption melting profiles, and electrophoretic methods. We showed that parallel quadruplexes are significantly more sensitive towards guanine substitutions than antiparallel ones. Furthermore, guanine-substituted variants, which in principle might correspond to native genomic sequences, distinctly differ in their biophysical properties, indicating that the four guanines in each tetrad of parallel quadruplexes are not equal. In addition, we were able to distinguish by CD an intramolecular G4 from intermolecular ones resulting from multimerisation mediated by terminal tetrad association, but not from intermolecular G4s formed due to inter-strand Hoogsteen hydrogen bond formation. In conclusion, our study indicates significant variability in parallel quadruplex structures, otherwise disregarded without detailed experimental analysis.
Collapse
Affiliation(s)
| | | | - Daniel Renčiuk
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 612 65 Brno, Czech Republic; (K.B.); (M.V.)
| |
Collapse
|
34
|
Abstract
Several decades elapsed between the first descriptions of G-quadruplex nucleic acid structures (G4s) assembled in vitro and the emergence of experimental findings indicating that such structures can form and function in living systems. A large body of evidence now supports roles for G4s in many aspects of nucleic acid biology, spanning processes from transcription and chromatin structure, mRNA processing, protein translation, DNA replication and genome stability, and telomere and mitochondrial function. Nonetheless, it must be acknowledged that some of this evidence is tentative, which is not surprising given the technical challenges associated with demonstrating G4s in biology. Here I provide an overview of evidence for G4 biology, focusing particularly on the many potential pitfalls that can be encountered in its investigation, and briefly discuss some of broader biological processes that may be impacted by G4s including cancer.
Collapse
Affiliation(s)
- F. Brad Johnson
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, United States
| |
Collapse
|
35
|
Ciszewski L, Lu-Nguyen N, Slater A, Brennan A, Williams HEL, Dickson G, Searle MS, Popplewell L. G-quadruplex ligands mediate downregulation of DUX4 expression. Nucleic Acids Res 2020; 48:4179-4194. [PMID: 32182342 PMCID: PMC7192601 DOI: 10.1093/nar/gkaa146] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 01/29/2020] [Accepted: 03/03/2020] [Indexed: 12/26/2022] Open
Abstract
Abnormal DUX4 expression in skeletal muscles plays a key role in facioscapulohumeral muscular dystrophy (FSHD) pathogenesis, although the molecular mechanisms regulating DUX4 expression are not fully defined. Using bioinformatic analysis of the genomic DUX4 locus, we have identified a number of putative G-quadruplexes (GQs) forming sequences. Their presence was confirmed in synthetic oligonucleotiode sequences derived from the enhancer, promoter and transcript of DUX4 through circular dichroism and nuclear magnetic resonance analysis. We further examined the binding affinity of a naturally occurring GQ stabilizing compound, berberine, to these non-canonical genetic structures using UV–Vis and fluorescence spectroscopy. Subsequent in vitro study in FSHD patient myoblasts indicated that berberine treatment reduced DUX4 expression and also expression of genes normally switched on by DUX4. Further investigation in a mouse model overexpressing exogenous DUX4 confirmed the therapeutic effects of berberine in downregulating DUX4 protein expression, inhibiting muscle fibrosis, and consequently rescuing muscle function. Our data demonstrate for the first time that GQs are present in the DUX4 locus and that the GQ interactive ligand reduces DUX4 expression suggesting potential role of GQs in FSHD pathogenesis. Our work provides the basis of a novel therapeutic strategy for the treatment of FSHD.
Collapse
Affiliation(s)
- Lukasz Ciszewski
- Department of Biological Sciences, Royal Holloway-University of London, Egham, Surrey TW20 0EX, UK
| | - Ngoc Lu-Nguyen
- Department of Biological Sciences, Royal Holloway-University of London, Egham, Surrey TW20 0EX, UK
| | - Alex Slater
- Centre for Biomolecular Sciences, School of Chemistry, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - Andrew Brennan
- Centre for Biomolecular Sciences, School of Chemistry, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - Huw E L Williams
- Centre for Biomolecular Sciences, School of Chemistry, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - George Dickson
- Department of Biological Sciences, Royal Holloway-University of London, Egham, Surrey TW20 0EX, UK
| | - Mark S Searle
- Centre for Biomolecular Sciences, School of Chemistry, University Park, University of Nottingham, Nottingham NG7 2RD, UK
| | - Linda Popplewell
- Department of Biological Sciences, Royal Holloway-University of London, Egham, Surrey TW20 0EX, UK
| |
Collapse
|
36
|
Jara-Espejo M, Fleming AM, Burrows CJ. Potential G-Quadruplex Forming Sequences and N6-Methyladenosine Colocalize at Human Pre-mRNA Intron Splice Sites. ACS Chem Biol 2020; 15:1292-1300. [PMID: 32396327 PMCID: PMC7309266 DOI: 10.1021/acschembio.0c00260] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Maturation of mRNA in humans involves modifying the 5' and 3' ends, splicing introns, and installing epitranscriptomic modifications that are essential for mRNA biogenesis. With respect to epitranscriptomic modifications, they are usually installed in specific consensus motifs, although not all sequences are modified suggesting a secondary structural component to site selection. Using bioinformatic analysis of published data, we identify in human mature-mRNA that potential RNA G-quadruplex (rG4) sequences colocalize with the epitranscriptomic modifications N6-methyladenosine (m6A), pseudouridine (Ψ), and inosine (I). Using the only available pre-mRNA data sets from the literature, we demonstrate colocalization of potential rG4s and m6A was greatest overall and occurred in introns near 5' and 3' splice sites. The loop lengths and sequence context of the m6A-bearing potential rG4s exhibited short loops most commonly comprised of single A nucleotides. This observation is consistent with a literature report of intronic m6A found in SAG (S = C or G) consensus motifs that are also recognized by splicing factors. The localization of m6A and potential rG4s in pre-mRNA at intron splice junctions suggests that these features could function together in alternative splicing. A similar analysis for potential rG4s around sites of Ψ installation or A-to-I editing in mRNA also found a colocalization; however, the frequency was less than that observed with m6A. These bioinformatic analyses guide a discussion of future experiments to understand how noncanonical rG4 structures may collaborate with epitranscriptomic modifications in the human cellular context to impact cellular phenotype.
Collapse
Affiliation(s)
- Manuel Jara-Espejo
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
- Department of Morphology, Piracicaba Dental School, University of Campinas-UNICAMP, Av. Limeira 901, Piracicaba, CEP 13414-018 Sao Paulo, Brazil
| | - Aaron M. Fleming
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| | - Cynthia J. Burrows
- Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, Utah 84112-0850, United States
| |
Collapse
|
37
|
Reina C, Cavalieri V. Epigenetic Modulation of Chromatin States and Gene Expression by G-Quadruplex Structures. Int J Mol Sci 2020; 21:E4172. [PMID: 32545267 PMCID: PMC7312119 DOI: 10.3390/ijms21114172] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 06/07/2020] [Accepted: 06/10/2020] [Indexed: 02/07/2023] Open
Abstract
G-quadruplexes are four-stranded helical nucleic acid structures formed by guanine-rich sequences. A considerable number of studies have revealed that these noncanonical structural motifs are widespread throughout the genome and transcriptome of numerous organisms, including humans. In particular, G-quadruplexes occupy strategic locations in genomic DNA and both coding and noncoding RNA molecules, being involved in many essential cellular and organismal functions. In this review, we first outline the fundamental structural features of G-quadruplexes and then focus on the concept that these DNA and RNA structures convey a distinctive layer of epigenetic information that is critical for the complex regulation, either positive or negative, of biological activities in different contexts. In this framework, we summarize and discuss the proposed mechanisms underlying the functions of G-quadruplexes and their interacting factors. Furthermore, we give special emphasis to the interplay between G-quadruplex formation/disruption and other epigenetic marks, including biochemical modifications of DNA bases and histones, nucleosome positioning, and three-dimensional organization of chromatin. Finally, epigenetic roles of RNA G-quadruplexes in post-transcriptional regulation of gene expression are also discussed. Undoubtedly, the issues addressed in this review take on particular importance in the field of comparative epigenetics, as well as in translational research.
Collapse
Affiliation(s)
- Chiara Reina
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties (PROMISE), University of Palermo, 90127 Palermo, Italy;
| | - Vincenzo Cavalieri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, 90128 Palermo, Italy
| |
Collapse
|
38
|
Herbert A. ALU non-B-DNA conformations, flipons, binary codes and evolution. ROYAL SOCIETY OPEN SCIENCE 2020; 7:200222. [PMID: 32742689 PMCID: PMC7353975 DOI: 10.1098/rsos.200222] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/18/2020] [Indexed: 05/08/2023]
Abstract
ALUs contribute to genetic diversity by altering DNA's linear sequence through retrotransposition, recombination and repair. ALUs also have the potential to form alternative non-B-DNA conformations such as Z-DNA, triplexes and quadruplexes that alter the read-out of information from the genome. I suggest here these structures enable the rapid reprogramming of cellular pathways to offset DNA damage and regulate inflammation. The experimental data supporting this form of genetic encoding is presented. ALU sequence motifs that form non-B-DNA conformations under physiological conditions are called flipons. Flipons are binary switches. They are dissipative structures that trade energy for information. By efficiently targeting cellular machines to active genes, flipons expand the repertoire of RNAs compiled from a gene. Their action greatly increases the informational capacity of linearly encoded genomes. Flipons are programmable by epigenetic modification, synchronizing cellular events by altering both chromatin state and nucleosome phasing. Different classes of flipon exist. Z-flipons are based on Z-DNA and modify the transcripts compiled from a gene. T-flipons are based on triplexes and localize non-coding RNAs that direct the assembly of cellular machines. G-flipons are based on G-quadruplexes and sense DNA damage, then trigger the appropriate protective responses. Flipon conformation is dynamic, changing with context. When frozen in one state, flipons often cause disease. The propagation of flipons throughout the genome by ALU elements represents a novel evolutionary innovation that allows for rapid change. Each ALU insertion creates variability by extracting a different set of information from the neighbourhood in which it lands. By elaborating on already successful adaptations, the newly compiled transcripts work with the old to enhance survival. Systems that optimize flipon settings through learning can adapt faster than with other forms of evolution. They avoid the risk of relying on random and irreversible codon rewrites.
Collapse
|
39
|
Chow EYC, Lyu K, Kwok CK, Chan TF. rG4-seeker enables high-confidence identification of novel and non-canonical rG4 motifs from rG4-seq experiments. RNA Biol 2020; 17:903-917. [PMID: 32338139 PMCID: PMC7577744 DOI: 10.1080/15476286.2020.1740470] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We recently developed the rG4-seq method to detect and map in vitro RNA G-quadruplex (rG4s) structures on a transcriptome-wide scale. rG4-seq of purified human HeLa RNA has revealed many non-canonical rG4s and the effects adjacent sequences have on rG4 formation. In this study, we aimed to improve the outcomes and false-positive discrimination in rG4-seq experiments using a bioinformatic approach. By establishing connections between rG4-seq library preparation chemistry and the underlying properties of sequencing data, we identified how to mitigate indigenous sampling errors and background noise in rG4-seq. We applied these findings to develop a novel bioinformatics pipeline named rG4-seeker (https://github.com/TF-Chan-Lab/rG4-seeker), which uses tailored noise models to autonomously assess and optimize rG4 detections in a replicate-independent manner. Compared with previous methods, rG4-seeker exhibited better false-positive discrimination and improved sensitivity for non-canonical rG4s. Using rG4-seeker, we identified novel features in rG4 formation that were missed previously. rG4-seeker provides a reliable and sensitive approach for rG4-seq investigations, laying the foundations for further elucidation of rG4 biology.
Collapse
Affiliation(s)
- Eugene Yui-Ching Chow
- School of Life Sciences, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong , Shatin, Hong Kong SAR, China
| | - Kaixin Lyu
- Department of Chemistry, City University of Hong Kong , Kowloon Tong, Hong Kong SAR, China
| | - Chun Kit Kwok
- Department of Chemistry, City University of Hong Kong , Kowloon Tong, Hong Kong SAR, China.,Shenzhen Research Institute of City University of Hong Kong , Shenzhen, China
| | - Ting-Fung Chan
- School of Life Sciences, and State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong , Shatin, Hong Kong SAR, China
| |
Collapse
|
40
|
Saha A, Duchambon P, Masson V, Loew D, Bombard S, Teulade-Fichou MP. Nucleolin Discriminates Drastically between Long-Loop and Short-Loop Quadruplexes. Biochemistry 2020; 59:1261-1272. [PMID: 32191439 DOI: 10.1021/acs.biochem.9b01094] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We investigate herein the interaction between nucleolin (NCL) and a set of G4 sequences derived from the CEB25 human minisatellite that adopt a parallel topology while differing in the length of the central loop (from nine nucleotides to one nucleotide). It is revealed that NCL strongly binds to long-loop (five to nine nucleotides) G4 while interacting weakly with the shorter variants (loop with fewer than three nucleotides). Photo-cross-linking experiments using 5-bromo-2'-deoxyuridine (BrU)-modified sequences further confirmed the loop-length dependency, thereby indicating that the WT-CEB25-L191 (nine-nucleotide loop) is the best G4 substrate. Quantitative proteomic analysis (LC-MS/MS) of the product(s) obtained by photo-cross-linking NCL to this sequence enabled the identification of one contact site corresponding to a 15-amino acid fragment located in helix α2 of RNA binding domain 2 (RBD2), which sheds light on the role of this structural element in G4-loop recognition. Then, the ability of a panel of benchmark G4 ligands to prevent the NCL-G4 interaction was explored. It was found that only the most potent ligand PhenDC3 can inhibit NCL binding, thereby suggesting that the terminal guanine quartet is also a strong determinant of G4 recognition, putatively through interaction with the RGG domain. This study describes the molecular mechanism by which NCL recognizes G4-containing long loops and leads to the proposal of a model implying a concerted action of RBD2 and RGG domains to achieve specific G4 recognition via a dual loop-quartet interaction.
Collapse
Affiliation(s)
- Abhijit Saha
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, 91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris Saclay, 91405 Orsay, France
| | - Patricia Duchambon
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, 91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris Saclay, 91405 Orsay, France
| | - Vanessa Masson
- Institut Curie, PSL Research University, Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, 26 rue d'Ulm, Paris 75248 Cedex 05, France
| | - Damarys Loew
- Institut Curie, PSL Research University, Centre de Recherche, Laboratoire de Spectrométrie de Masse Protéomique, 26 rue d'Ulm, Paris 75248 Cedex 05, France
| | - Sophie Bombard
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, 91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris Saclay, 91405 Orsay, France
| | - Marie-Paule Teulade-Fichou
- CNRS UMR9187, INSERM U1196, Institut Curie, PSL Research University, 91405 Orsay, France
- CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris Saclay, 91405 Orsay, France
| |
Collapse
|
41
|
Moruno-Manchon JF, Lejault P, Wang Y, McCauley B, Honarpisheh P, Morales Scheihing DA, Singh S, Dang W, Kim N, Urayama A, Zhu L, Monchaud D, McCullough LD, Tsvetkov AS. Small-molecule G-quadruplex stabilizers reveal a novel pathway of autophagy regulation in neurons. eLife 2020; 9:e52283. [PMID: 32043463 PMCID: PMC7012600 DOI: 10.7554/elife.52283] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 01/07/2020] [Indexed: 12/22/2022] Open
Abstract
Guanine-rich DNA sequences can fold into four-stranded G-quadruplex (G4-DNA) structures. G4-DNA regulates replication and transcription, at least in cancer cells. Here, we demonstrate that, in neurons, pharmacologically stabilizing G4-DNA with G4 ligands strongly downregulates the Atg7 gene. Atg7 is a critical gene for the initiation of autophagy that exhibits decreased transcription with aging. Using an in vitro assay, we show that a putative G-quadruplex-forming sequence (PQFS) in the first intron of the Atg7 gene folds into a G4. An antibody specific to G4-DNA and the G4-DNA-binding protein PC4 bind to the Atg7 PQFS. Mice treated with a G4 stabilizer develop memory deficits. Brain samples from aged mice contain G4-DNA structures that are absent in brain samples from young mice. Overexpressing the G4-DNA helicase Pif1 in neurons exposed to the G4 stabilizer improves phenotypes associated with G4-DNA stabilization. Our findings indicate that G4-DNA is a novel pathway for regulating autophagy in neurons.
Collapse
Affiliation(s)
- Jose F Moruno-Manchon
- Department of Neurobiology and AnatomyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - Pauline Lejault
- Institut de Chimie Moléculaire (ICMUB), UBFC Dijon, CNRS UMR6302DijonFrance
| | - Yaoxuan Wang
- Department of Neurobiology and AnatomyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - Brenna McCauley
- Huffington Center on AgingBaylor College of MedicineHoustonUnited States
| | - Pedram Honarpisheh
- Department of NeurologyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
- The University of Texas Graduate School of Biomedical SciencesHoustonUnited States
| | - Diego A Morales Scheihing
- Department of NeurologyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - Shivani Singh
- Department of Microbiology and Molecular GeneticsThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - Weiwei Dang
- Huffington Center on AgingBaylor College of MedicineHoustonUnited States
| | - Nayun Kim
- Department of Microbiology and Molecular GeneticsThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - Akihiko Urayama
- Department of NeurologyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
- The University of Texas Graduate School of Biomedical SciencesHoustonUnited States
| | - Liang Zhu
- Biostatistics and Epidemiology Research Design Core Center for Clinical and Translational SciencesThe University of Texas McGovern Medical School at HoustonHoustonUnited States
- Department of Internal MedicineThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| | - David Monchaud
- Institut de Chimie Moléculaire (ICMUB), UBFC Dijon, CNRS UMR6302DijonFrance
| | - Louise D McCullough
- Department of NeurologyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
- The University of Texas Graduate School of Biomedical SciencesHoustonUnited States
| | - Andrey S Tsvetkov
- Department of Neurobiology and AnatomyThe University of Texas McGovern Medical School at HoustonHoustonUnited States
- The University of Texas Graduate School of Biomedical SciencesHoustonUnited States
- UTHealth Consortium on AgingThe University of Texas McGovern Medical School at HoustonHoustonUnited States
| |
Collapse
|
42
|
Fleming AM, Burrows CJ. Interplay of Guanine Oxidation and G-Quadruplex Folding in Gene Promoters. J Am Chem Soc 2020; 142:1115-1136. [PMID: 31880930 PMCID: PMC6988379 DOI: 10.1021/jacs.9b11050] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Living in an oxygen atmosphere demands an ability to thrive in the presence of reactive oxygen species (ROS). Aerobic organisms have successfully found solutions to the oxidative threats imposed by ROS by evolving an elaborate detoxification system, upregulating ROS during inflammation, and utilizing ROS as messenger molecules. In this Perspective, recent studies are discussed that demonstrate ROS as signaling molecules for gene regulation by combining two emergent properties of the guanine (G) heterocycle in DNA, namely, oxidation sensitivity and a propensity for G-quadruplex (G4) folding, both of which depend upon sequence context. In human gene promoters, this results from an elevated 5'-GG-3' dinucleotide frequency and GC enrichment near transcription start sites. Oxidation of DNA by ROS drives conversion of G to 8-oxo-7,8-dihydroguanine (OG) to mark target promoters for base excision repair initiated by OG-glycosylase I (OGG1). Sequence-dependent mechanisms for gene activation are available to OGG1 to induce transcription. Either OGG1 releases OG to yield an abasic site driving formation of a non-canonical fold, such as a G4, to be displayed to apurinic/apyrimidinic 1 (APE1) and stalling on the fold to recruit activating factors, or OGG1 binds OG and facilitates activator protein recruitment. The mechanisms described drive induction of stress response, DNA repair, or estrogen-induced genes, and these pathways are novel potential anticancer targets for therapeutic intervention. Chemical concepts provide a framework to discuss the regulatory or possible epigenetic potential of the OG modification in DNA, in which DNA "damage" and non-canonical folds collaborate to turn on or off gene expression. The next steps for scientific discovery in this growing field are discussed.
Collapse
Affiliation(s)
- Aaron M. Fleming
- 315 South 1400 East, Dept. of Chemistry, University of Utah, Salt Lake City, UT 84112-0850, USA
| | - Cynthia J. Burrows
- 315 South 1400 East, Dept. of Chemistry, University of Utah, Salt Lake City, UT 84112-0850, USA
| |
Collapse
|
43
|
Puig Lombardi E, Londoño-Vallejo A. A guide to computational methods for G-quadruplex prediction. Nucleic Acids Res 2020; 48:1-15. [PMID: 31754698 PMCID: PMC6943126 DOI: 10.1093/nar/gkz1097] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/31/2019] [Accepted: 11/04/2019] [Indexed: 12/31/2022] Open
Abstract
Guanine-rich nucleic acids can fold into the non-B DNA or RNA structures called G-quadruplexes (G4). Recent methodological developments have allowed the characterization of specific G-quadruplex structures in vitro as well as in vivo, and at a much higher throughput, in silico, which has greatly expanded our understanding of G4-associated functions. Typically, the consensus motif G3+N1-7G3+N1-7G3+N1-7G3+ has been used to identify potential G-quadruplexes from primary sequence. Since, various algorithms have been developed to predict the potential formation of quadruplexes directly from DNA or RNA sequences and the number of studies reporting genome-wide G4 exploration across species has rapidly increased. More recently, new methodologies have also appeared, proposing other estimates which consider non-canonical sequences and/or structure propensity and stability. The present review aims at providing an updated overview of the current open-source G-quadruplex prediction algorithms and straightforward examples of their implementation.
Collapse
Affiliation(s)
- Emilia Puig Lombardi
- Telomeres and Cancer Laboratory, Institut Curie, PSL Research University, Sorbonne Universités, CNRS UMR3244, 75005 Paris, France
| | - Arturo Londoño-Vallejo
- Telomeres and Cancer Laboratory, Institut Curie, PSL Research University, Sorbonne Universités, CNRS UMR3244, 75005 Paris, France
| |
Collapse
|
44
|
Meeting report: Seventh International Meeting on Quadruplex Nucleic Acids (Changchun, P.R. China, September 6–9, 2019). Biochimie 2020; 168:100-109. [DOI: 10.1016/j.biochi.2019.10.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 10/31/2019] [Indexed: 12/24/2022]
|
45
|
Parekh VJ, Niccum BA, Shah R, Rivera MA, Novak MJ, Geinguenaud F, Wien F, Arluison V, Sinden RR. Role of Hfq in Genome Evolution: Instability of G-Quadruplex Sequences in E. coli. Microorganisms 2019; 8:microorganisms8010028. [PMID: 31877879 PMCID: PMC7023247 DOI: 10.3390/microorganisms8010028] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 11/16/2022] Open
Abstract
Certain G-rich DNA repeats can form quadruplex in bacterial chromatin that can present blocks to DNA replication and, if not properly resolved, may lead to mutations. To understand the participation of quadruplex DNA in genomic instability in Escherichia coli (E. coli), mutation rates were measured for quadruplex-forming DNA repeats, including (G3T)4, (G3T)8, and a RET oncogene sequence, cloned as the template or nontemplate strand. We evidence that these alternative structures strongly influence mutagenesis rates. Precisely, our results suggest that G-quadruplexes form in E. coli cells, especially during transcription when the G-rich strand can be displaced by R-loop formation. Structure formation may then facilitate replication misalignment, presumably associated with replication fork blockage, promoting genomic instability. Furthermore, our results also evidence that the nucleoid-associated protein Hfq is involved in the genetic instability associated with these sequences. Hfq binds and stabilizes G-quadruplex structure in vitro and likely in cells. Collectively, our results thus implicate quadruplexes structures and Hfq nucleoid protein in the potential for genetic change that may drive evolution or alterations of bacterial gene expression.
Collapse
Affiliation(s)
- Virali J. Parekh
- Laboratory of DNA Structure and Mutagenesis, Department of Chemistry and Applied Biological Sciences, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA;
| | - Brittany A. Niccum
- Department of Mathematics, Florida Institute of Technology, Melbourne, FL 32901, USA;
| | - Rachna Shah
- Department of Biological Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (R.S.); (M.A.R.)
| | - Marisa A. Rivera
- Department of Biological Sciences, Florida Institute of Technology, Melbourne, FL 32901, USA; (R.S.); (M.A.R.)
| | - Mark J. Novak
- Department of Chemistry and Applied Biological Sciences, South Dakota School of Mines and Technology; Rapid City, SD 57701, USA;
| | - Frederic Geinguenaud
- Plateforme CNanoMat & Inserm U1148, Laboratory for Vascular Translational Science, UFR SMBH, Université Paris 13, Sorbonne Paris Cité, F-93017 Bobigny, France;
| | - Frank Wien
- Synchrotron SOLEIL, 91192 Gif-sur-Yvette, France;
| | - Véronique Arluison
- Laboratoire Léon Brillouin LLB, CEA, CNRS UMR12, Université Paris Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France
- Université de Paris, UFR Sciences du vivant, 35 rue Hélène Brion, 75205 Paris cedex, France
- Correspondence: (V.A.); (R.R.S.); Tel.: +1-605-394-1678 (R.R.S.)
| | - Richard R. Sinden
- Laboratory of DNA Structure and Mutagenesis, Department of Chemistry and Applied Biological Sciences, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA;
- Correspondence: (V.A.); (R.R.S.); Tel.: +1-605-394-1678 (R.R.S.)
| |
Collapse
|
46
|
Gray LT, Puig Lombardi E, Verga D, Nicolas A, Teulade-Fichou MP, Londoño-Vallejo A, Maizels N. G-quadruplexes Sequester Free Heme in Living Cells. Cell Chem Biol 2019; 26:1681-1691.e5. [PMID: 31668518 DOI: 10.1016/j.chembiol.2019.10.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 08/13/2019] [Accepted: 10/02/2019] [Indexed: 02/07/2023]
Abstract
Heme is an essential cofactor for many enzymes, but free heme is toxic and its levels are tightly regulated. G-quadruplexes bind heme avidly in vitro, raising the possibility that they may sequester heme in vivo. If so, then treatment that displaces heme from quadruplexes is predicted to induce expression of genes involved in iron and heme homeostasis. Here we show that PhenDC3, a G-quadruplex ligand structurally unrelated to heme, displaces quadruplex-bound heme in vitro and alters transcription in cultured human cells, upregulating genes that support heme degradation and iron homeostasis, and most strikingly causing a 30-fold induction of heme oxidase 1, the key enzyme in heme degradation. We propose that G-quadruplexes sequester heme to protect cells from the pathophysiological consequences of free heme.
Collapse
Affiliation(s)
- Lucas T Gray
- Department of Immunology, University of Washington, 1959 NE Pacific St., Seattle, WA 98195, USA
| | - Emilia Puig Lombardi
- Institut Curie, Centre de Recherche, CNRS-UMR3244, PSL Research University, Paris 75005, France
| | - Daniela Verga
- Institut Curie, Centre de Recherche, CNRS-UMR9187, INSERM-U1196, PSL Research University, Sorbonne Universités, Orsay 91405, France; CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, Orsay 91405, France
| | - Alain Nicolas
- Institut Curie, Centre de Recherche, CNRS-UMR3244, PSL Research University, Paris 75005, France
| | - Marie-Paule Teulade-Fichou
- Institut Curie, Centre de Recherche, CNRS-UMR9187, INSERM-U1196, PSL Research University, Sorbonne Universités, Orsay 91405, France; CNRS UMR9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, Orsay 91405, France
| | - Arturo Londoño-Vallejo
- Institut Curie, Centre de Recherche, CNRS-UMR3244, PSL Research University, Paris 75005, France
| | - Nancy Maizels
- Department of Immunology, University of Washington, 1959 NE Pacific St., Seattle, WA 98195, USA; Department of Biochemistry, University of Washington, 1959 NE Pacific St., Seattle, WA 98195, USA.
| |
Collapse
|
47
|
Identification of putative G-quadruplex DNA structures in S. pombe genome by quantitative PCR stop assay. DNA Repair (Amst) 2019; 82:102678. [DOI: 10.1016/j.dnarep.2019.102678] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 07/08/2019] [Accepted: 07/26/2019] [Indexed: 12/31/2022]
|
48
|
Jara-Espejo M, Line SR. DNA G-quadruplex stability, position and chromatin accessibility are associated with CpG island methylation. FEBS J 2019; 287:483-495. [PMID: 31532882 DOI: 10.1111/febs.15065] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 07/22/2019] [Accepted: 09/16/2019] [Indexed: 01/06/2023]
Abstract
CpG islands (CGI) are genomic regions associated with gene promoters and involved in gene expression regulation. Despite their high CpG content and unlike bulk genomic DNA methylation pattern, these regions are usually hypomethylated. So far, the mechanisms controlling the CGI methylation patterning remain unclear. G-quadruplex (G4) structures can inhibit DNA methyltransferases 1 enzymatic activity, leading to CGI hypomethylation. Our aim was to analyse the association of G4 forming sequences (G4FS) and CGI methylation as well as to determine the intrinsic and extrinsic characteristics of G4FS that may modulate this phenomenon. Using methylation data from human embryonic stem cells (hESCs) and three hESC-derived populations, we showed that hypomethylated CpGs located inside CGI (CGI/CpG) tend to be associated with highly stable G4FS (Minimum free energy ≤ -30 kcal·mol-1 ). The association of highly stable G4FS and hypomethylation tend to be stronger when these structures are located at shorter distances (~ < 150 bp) from GCI/CpGs, when G4FS and CpGs are located within open chromatin and G4FS are inside CGI. Moreover, this association is not strongly influenced by the CpG content of CGI. Conversely, highly methylated CGI/CpG tend to be associated with low stability G4FS. Although CpGs inside CGIs without a G4FS tend to be more methylated, high stability G4FS within CGI neighbourhood were associated with decreased methylation. In summary, our data indicate that G4FS may act as protective cis elements against CGI methylation, and this effect seems to be influenced by the G4FS folding potential, its presence within CGI, CpG distance from G4FS and chromatin accessibility.
Collapse
Affiliation(s)
- Manuel Jara-Espejo
- Department of Morphology, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, Brazil
| | - Sérgio Roberto Line
- Department of Morphology, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, Brazil
| |
Collapse
|
49
|
Puig Lombardi E, Londoño-Vallejo A, Nicolas A. Relationship Between G-Quadruplex Sequence Composition in Viruses and Their Hosts. Molecules 2019; 24:molecules24101942. [PMID: 31137580 PMCID: PMC6572409 DOI: 10.3390/molecules24101942] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Revised: 05/16/2019] [Accepted: 05/16/2019] [Indexed: 12/19/2022] Open
Abstract
A subset of guanine-rich nucleic acid sequences has the potential to fold into G-quadruplex (G4) secondary structures, which are functionally important for several biological processes, including genome stability and regulation of gene expression. Putative quadruplex sequences (PQSs) G3+N1-7G3+N1-7G3+N1-7G3+ are widely found in eukaryotic and prokaryotic genomes, but the base composition of the N1-7 loops is biased across species. Since the viruses partially hijack their hosts' cellular machinery for proliferation, we examined the PQS motif size, loop length, and nucleotide compositions of 7370 viral genome assemblies and compared viral and host PQS motifs. We studied seven viral taxa infecting five distant eukaryotic hosts and created a resource providing a comprehensive view of the viral quadruplex motifs. Overall, short-looped PQSs are predominant and with a similar composition across viral taxonomic groups, albeit subtle trends emerge upon classification by hosts. Specifically, there is a higher frequency of pyrimidine loops in viruses infecting animals irrespective of the viruses' genome type. This observation is confirmed by an in-depth analysis of the Herpesviridae family of viruses, which showed a distinctive accumulation of thermally stable C-looped quadruplexes in viruses infecting high-order vertebrates. The occurrence of viral C-looped G4s, which carry binding sites for host transcription factors, as well as the high prevalence of viral TTA-looped G4s, which are identical to vertebrate telomeric motifs, provide concrete examples of how PQSs may help viruses impinge upon, and benefit from, host functions. More generally, these observations suggest a co-evolution of virus and host PQSs, thus underscoring the potential functional significance of G4s.
Collapse
Affiliation(s)
- Emilia Puig Lombardi
- Institut Curie, PSL Research University, UMR3244 CNRS, 75248 Paris CEDEX 05, France.
| | | | - Alain Nicolas
- Institut Curie, PSL Research University, UMR3244 CNRS, 75248 Paris CEDEX 05, France.
| |
Collapse
|