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Michael Sabo T, Trent JO, Chaires JB, Monsen RC. Strategy for modeling higher-order G-quadruplex structures recalcitrant to NMR determination. Methods 2024; 230:9-20. [PMID: 39032720 DOI: 10.1016/j.ymeth.2024.07.004] [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: 04/05/2024] [Revised: 06/22/2024] [Accepted: 07/17/2024] [Indexed: 07/23/2024] Open
Abstract
Guanine-rich nucleic acids can form intramolecularly folded four-stranded structures known as G-quadruplexes (G4s). Traditionally, G4 research has focused on short, highly modified DNA or RNA sequences that form well-defined homogeneous compact structures. However, the existence of longer sequences with multiple G4 repeats, from proto-oncogene promoters to telomeres, suggests the potential for more complex higher-order structures with multiple G4 units that might offer selective drug-targeting sites for therapeutic development. These larger structures present significant challenges for structural characterization by traditional high-resolution methods like multi-dimensional NMR and X-ray crystallography due to their molecular complexity. To address this current challenge, we have developed an integrated structural biology (ISB) platform, combining experimental and computational methods to determine self-consistent molecular models of higher-order G4s (xG4s). Here we outline our ISB method using two recent examples from our lab, an extended c-Myc promoter and long human telomere G4 repeats, that highlights the utility and generality of our approach to characterizing biologically relevant xG4s.
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Affiliation(s)
- T Michael Sabo
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - John O Trent
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Jonathan B Chaires
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Robert C Monsen
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY, United States.
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2
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Štefan U, Brázda V, Plavec J, Marušič M. The influence of G-tract and loop length on the topological variability of putative five and six G-quartet DNA structures in the human genome. Int J Biol Macromol 2024; 280:136008. [PMID: 39326605 DOI: 10.1016/j.ijbiomac.2024.136008] [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: 04/08/2024] [Revised: 09/23/2024] [Accepted: 09/23/2024] [Indexed: 09/28/2024]
Abstract
Local variation of DNA structure and its dynamic nature play an essential role in the regulation of important biological processes. One of the most prominent noncanonical structures are G-quadruplexes, which form in vivo within guanine-rich regions and have been demonstrated to be involved in the regulation of transcription, translation and telomere maintenance. We provide an analysis of G-quadruplex formation in sequences with five and six guanine residues long G-tracts, which have emerged from the investigation of the gapless human genome and are associated with genes related to cancer and neurodegenerative diseases. We systematically explored the effect of G-tract and loop elongations by means of NMR and CD spectroscopy and polyacrylamide electrophoresis. Despite both types of elongation leading up to structural polymorphism, we successfully determined the topologies of four out of eight examined sequences, one of which contributes to a very scarce selection of currently known intramolecular four G-quartet structures in potassium solutions. We demonstrate that examined sequences are incompatible with five or six G-quartet structures with propeller loops, although the compatibility with other loop types cannot be factored out. Lastly, we propose a novel approach towards specific G-quadruplex targeting that could be implemented in structures with more than four G-quartets.
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Affiliation(s)
- Urša Štefan
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Václav Brázda
- Institute of Biophysics of the Czech Academy of Sciences, Královopolská 135, 61265 Brno, Czech Republic
| | - Janez Plavec
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia; Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; EN-FIST Center of Excellence, SI-1000 Ljubljana, Slovenia
| | - Maja Marušič
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia.
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3
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Roy SS, Bagri S, Vinayagamurthy S, Sengupta A, Then CR, Kumar R, Sridharan S, Chowdhury S. Artificially inserted strong promoter containing multiple G-quadruplexes induces long-range chromatin modification. eLife 2024; 13:RP96216. [PMID: 39158543 PMCID: PMC11333042 DOI: 10.7554/elife.96216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2024] Open
Abstract
Although the role of G-quadruplex (G4) DNA structures has been suggested in chromosomal looping this was not tested directly. Here, to test causal function, an array of G4s, or control sequence that does not form G4s, were inserted within chromatin in cells. In vivo G4 formation of the inserted G4 sequence array, and not the control sequence, was confirmed using G4-selective antibody. Compared to the control insert, we observed a remarkable increase in the number of 3D chromatin looping interactions from the inserted G4 array. This was evident within the immediate topologically associated domain (TAD) and throughout the genome. Locally, recruitment of enhancer histone marks and the transcriptional coactivator p300/Acetylated-p300 increased in the G4-array, but not in the control insertion. Resulting promoter-enhancer interactions and gene activation were clear up to 5 Mb away from the insertion site. Together, these show the causal role of G4s in enhancer function and long-range chromatin interactions. Mechanisms of 3D topology are primarily based on DNA-bound architectural proteins that induce/stabilize long-range interactions. Involvement of the underlying intrinsic DNA sequence/structure in 3D looping shown here therefore throws new light on how long-range chromosomal interactions might be induced or maintained.
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Affiliation(s)
- Shuvra Shekhar Roy
- CSIR-Institute of Genomics and Integrative BiologyNew DelhiIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
| | - Sulochana Bagri
- CSIR-Institute of Genomics and Integrative BiologyNew DelhiIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
| | - Soujanya Vinayagamurthy
- CSIR-Institute of Genomics and Integrative BiologyNew DelhiIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
| | - Avik Sengupta
- Department of Biotechnology, Indian Institute of Technology HyderabadHyderabadIndia
| | - Claudia Regina Then
- Cancer Science Institute of Singapore, National University of SingaporeSingaporeSingapore
| | - Rahul Kumar
- Department of Biotechnology, Indian Institute of Technology HyderabadHyderabadIndia
| | - Sriram Sridharan
- Cancer Science Institute of Singapore, National University of SingaporeSingaporeSingapore
| | - Shantanu Chowdhury
- CSIR-Institute of Genomics and Integrative BiologyNew DelhiIndia
- Academy of Scientific and Innovative Research (AcSIR)GhaziabadIndia
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4
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Long W, Zeng YX, Zheng BX, Li YB, Wang YK, Chan KH, She MT, Lu YJ, Cao C, Wong WL. Targeting hTERT Promoter G-Quadruplex DNA Structures with Small-Molecule Ligand to Downregulate hTERT Expression for Triple-Negative Breast Cancer Therapy. J Med Chem 2024; 67:13363-13382. [PMID: 38987863 DOI: 10.1021/acs.jmedchem.4c01255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
Human telomerase reverse transcriptase (hTERT) may have noncanonical functions in transcriptional regulation and metabolic reprogramming in cancer cells, but it is a challenging target. We thus developed small-molecule ligands targeting hTERT promoter G-quadruplex DNA structures (hTERT G4) to downregulate hTERT expression. Ligand 5 showed high affinity toward hTERT G4 (Kd = 1.1 μM) and potent activity against triple-negative breast cancer cells (MDA-MB-231, IC50 = 1 μM). In cell-based assays, 5 not only exerts markedly inhibitory activity on classical telomere functions including decreased telomerase activity, shortened telomere length, and cellular senescence but also induces DNA damage, acute cellular senescence, and apoptosis. This study reveals that hTERT G4-targeting ligand may cause mitochondrial dysfunction, disrupt iron metabolism and activate ferroptosis in cancer cells. The in vivo antitumor efficacy of 5 was also evaluated in an MDA-MB-231 xenograft mouse model and approximately 78.7% tumor weight reduction was achieved. No observable toxicity against the major organs was observed.
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Affiliation(s)
- Wei Long
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Yao-Xun Zeng
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Bo-Xin Zheng
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Yu-Bo Li
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Ya-Kun Wang
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Ka-Hin Chan
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Meng-Ting She
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
| | - Yu-Jing Lu
- School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology Guangzhou 510006, China
| | - Chunyang Cao
- State Key Laboratory of Chemical Biology, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Wing-Leung Wong
- State Key Laboratory of Chemical Biology and Drug Discovery, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR 999077, China
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5
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Hussen AS, Kravitz HL, Freudenthal BD, Whitaker AM. Oxidative DNA damage on the VEGF G-quadruplex forming promoter is repaired via long-patch BER. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024; 65 Suppl 1:25-39. [PMID: 37606505 PMCID: PMC10984112 DOI: 10.1002/em.22570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/01/2023] [Accepted: 08/20/2023] [Indexed: 08/23/2023]
Abstract
In response to oxidative damage, base excision repair (BER) enzymes perturb the structural equilibrium of the VEGF promoter between B-form and G4 DNA conformations, resulting in epigenetic-like modifications of gene expression. However, the mechanistic details remain enigmatic, including the activity and coordination of BER enzymes on the damaged G4 promoter. To address this, we investigated the ability of each BER factor to conduct its repair activity on VEGF promoter G4 DNA substrates by employing pre-steady-state kinetics assays and in vitro coupled BER assays. OGG1 was able to initiate BER on double-stranded VEGF promoter G4 DNA substrates. Moreover, pre-steady-state kinetics revealed that compared to B-form DNA, APE1 repair activity on the G4 was decreased ~two-fold and is the result of slower product release as opposed to inefficient strand cleavage. Interestingly, Pol β performs multiple insertions on G4 substrates via strand displacement DNA synthesis in contrast to a single insertion on B-form DNA. The multiple insertions inhibit ligation of the Pol β products, and hence BER is not completed on the VEGF G4 promoter substrates through canonical short-patch BER. Instead, repair requires the long-patch BER flap-endonuclease activity of FEN1 in response to the multiple insertions by Pol β prior to ligation. Because the BER proteins and their repair activities are a key part of the VEGF transcriptional enhancement in response to oxidative DNA damage of the G4 VEGF promoter, the new insights reported here on BER activity in the context of this promoter are relevant toward understanding the mechanism of transcriptional regulation.
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Affiliation(s)
- Adil S. Hussen
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Haley L. Kravitz
- Nuclear Dynamics and Cancer Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
| | - Bret D. Freudenthal
- Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Amy M. Whitaker
- Nuclear Dynamics and Cancer Program, Fox Chase Cancer Center, Philadelphia, Pennsylvania, USA
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6
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Wang J, Qiao JQ, Zheng WJ, Lian HZ. Effect of ionic liquids as mobile phase additives on retention behaviors of G-quadruplexes in reversed-phase high performance liquid chromatography. J Chromatogr A 2024; 1715:464604. [PMID: 38176351 DOI: 10.1016/j.chroma.2023.464604] [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: 10/24/2023] [Revised: 12/20/2023] [Accepted: 12/22/2023] [Indexed: 01/06/2024]
Abstract
G-quadruplexes (G4s) play an important role in a variety of biological processes and have extensive application prospects. Due to the significance of G4s in physiology and biosensing, studies on G4s have attracted much attention, stimulating the development or improvement of methods for G4 structures and polymorphism analysis. In this work, ionic liquids (ILs) were involved as mobile phase additives in reversed-phase high performance liquid chromatography (RP-HPLC) to analyse G4s with various conformations for the first time. How ILs affected the retention behaviors of G4s was investigated comprehensively. It was found that the addition of ILs markedly enhanced G4 retention, along with obvious amelioration on chromatographic peak shapes and separation. The influence of pH of mobile phase and types of ILs were also included in order to acquire an in-depth understanding. It appeared that the effect of ILs on G4 retention behaviors was the result of a combination of various interactions between G4s with the hydrophobic stationary phase and with the IL-containing mobile phase, where ion pair mechanism and enhanced hydrophobic interaction dominated. The findings of this work revealed that ILs could effectively improve the separation of G4s in RP-HPLC, which was conducive to G4 structural analysis, especially for G4s polymorphism elucidation.
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Affiliation(s)
- Ju Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Jun-Qin Qiao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China.
| | - Wei-Juan Zheng
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Hong-Zhen Lian
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China.
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7
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Fleming AM, Omaga CA, Burrows CJ. NEIL3 promoter G-quadruplex with oxidatively modified bases shows magnesium-dependent folding that stalls polymerase bypass. Biochimie 2023; 214:156-166. [PMID: 37437684 PMCID: PMC10592359 DOI: 10.1016/j.biochi.2023.07.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 06/29/2023] [Accepted: 07/03/2023] [Indexed: 07/14/2023]
Abstract
Oxidative stress unleashes reactive species capable of oxidizing 2'-deoxyguanosine (G) nucleotides in G-rich sequences of the genome, such as the potential G-quadruplex forming sequencing (PQS) in the NEIL3 gene promoter. Oxidative modification of G yields 8-oxo-7,8-dihydro-2'-deoxyguanosine (OG) that can be further oxidized to hydantoin products. Herein, OG was synthesized into the NEIL3 PQS that was allowed to fold to a G-quadruplex (G4) in K+ ion solutions with varying amounts of Mg2+ in the physiological range. The Mg2+ dependency in the oxidatively modified NEIL3 G4 to stall a replicative DNA polymerase was evaluated. The polymerase was found to stall at the G4 or OG, as well as continue to full-length extension with dependency on the location of the modification and the concentration of Mg2+. To provide some clarity on these findings, OG or the hydantoins were synthesized in model NEIL3 G4 folding sequences at the positions of the polymerase study. The model G4 sequences were allowed to fold in K+ ion solutions with varying levels of Mg2+ to identify how the presence of the divalent metal impacted G4 folding depending on the location of the modification. The presence of Mg2+ either caused the transition of the NEIL3 G4 folds from an antiparallel to parallel orientation of the strands or had no impact. Structural models are proposed to understand the findings using the literature as a guide. The biological significance of the results is discussed.
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Affiliation(s)
- Aaron M Fleming
- Department of Chemistry, University of Utah, Salt Lake City, UT, 84112-0850, USA
| | - Carla A Omaga
- Department of Chemistry, University of Utah, Salt Lake City, UT, 84112-0850, USA
| | - Cynthia J Burrows
- Department of Chemistry, University of Utah, Salt Lake City, UT, 84112-0850, USA.
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8
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Romano F, Di Porzio A, Iaccarino N, Riccardi G, Di Lorenzo R, Laneri S, Pagano B, Amato J, Randazzo A. G-quadruplexes in cancer-related gene promoters: from identification to therapeutic targeting. Expert Opin Ther Pat 2023; 33:745-773. [PMID: 37855085 DOI: 10.1080/13543776.2023.2271168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
INTRODUCTION Guanine-rich DNA sequences can fold into four-stranded noncanonical secondary structures called G-quadruplexes (G4s) which are widely distributed in functional regions of the human genome, such as telomeres and gene promoter regions. Compelling evidence suggests their involvement in key genome functions such as gene expression and genome stability. Notably, the abundance of G4-forming sequences near transcription start sites suggests their potential involvement in regulating oncogenes. AREAS COVERED This review provides an overview of current knowledge on G4s in human oncogene promoters. The most representative G4-binding ligands have also been documented. The objective of this work is to present a comprehensive overview of the most promising targets for the development of novel and highly specific anticancer drugs capable of selectively impacting the expression of individual or a limited number of genes. EXPERT OPINION Modulation of G4 formation by specific ligands has been proposed as a powerful new tool to treat cancer through the control of oncogene expression. Actually, most of G4-binding small molecules seem to simultaneously target a range of gene promoter G4s, potentially influencing several critical driver genes in cancer, thus producing significant therapeutic benefits.
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Affiliation(s)
- Francesca Romano
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Anna Di Porzio
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Nunzia Iaccarino
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | | | | | - Sonia Laneri
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Bruno Pagano
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Jussara Amato
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Antonio Randazzo
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
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Ghezzo M, Trajkovski M, Plavec J, Sissi C. A Screening Protocol for Exploring Loop Length Requirements for the Formation of a Three Cytosine-Cytosine + Base-Paired i-Motif. Angew Chem Int Ed Engl 2023; 62:e202309327. [PMID: 37611164 DOI: 10.1002/anie.202309327] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/21/2023] [Accepted: 08/23/2023] [Indexed: 08/25/2023]
Abstract
DNA sequences containing at least four runs of repetitive cytosines can fold into tetra-helical structures called i-Motifs (iMs). The interest in these DNA secondary structures is increasing due to their therapeutical and technological applications. Still, limited knowledge of their folding requirements is currently available. We developed a novel step-by-step pipeline for the systematic screening of putative iM-forming model sequences. Focusing on structures comprising only three cytosine-cytosine+ base pairs, we investigated what the minimal lengths of the loops required for formation of an intra-molecular iM are. Our data indicate that two and three nucleotides are required to connect the strands through the minor and majorgrooves of the iM, respectively. Additionally, they highlight an asymmetric behavior according to the distribution of the cytosines. Specifically, no sequence containing a single cytosine in the first and third run was able to fold into intra-molecular iMs with the same stability of those formed when the first and the third run comprise two cytosines. This knowledge represents a step forward toward the development of prediction tools for the proper identification of biologically functional iMs, as well as for the rational design of these secondary structures as technological devices.
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Affiliation(s)
- Michele Ghezzo
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| | - Marko Trajkovski
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
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10
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Zhang ZH, Qian SH, Wei D, Chen ZX. In vivo dynamics and regulation of DNA G-quadruplex structures in mammals. Cell Biosci 2023; 13:117. [PMID: 37381029 DOI: 10.1186/s13578-023-01074-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Accepted: 06/19/2023] [Indexed: 06/30/2023] Open
Abstract
G-quadruplex (G4) is a four-stranded helical DNA secondary structure formed by guanine-rich sequence folding, and G4 has been computationally predicted to exist in a wide range of species. Substantial evidence has supported the formation of endogenous G4 (eG4) in living cells and revealed its regulatory dynamics and critical roles in several important biological processes, making eG4 a regulator of gene expression perturbation and a promising therapeutic target in disease biology. Here, we reviewed the methods for prediction of potential G4 sequences (PQS) and detection of eG4s. We also highlighted the factors affecting the dynamics of eG4s and the effects of eG4 dynamics. Finally, we discussed the future applications of eG4 dynamics in disease therapy.
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Affiliation(s)
- Ze-Hao Zhang
- Hubei Hongshan Laboratory, College of Life Science and Technology, College of Biomedicine and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, China
| | - Sheng Hu Qian
- Hubei Hongshan Laboratory, College of Life Science and Technology, College of Biomedicine and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, China
| | - Dengguo Wei
- College of Science, Huazhong Agricultural University, Wuhan, 430070, China
| | - Zhen-Xia Chen
- Hubei Hongshan Laboratory, College of Life Science and Technology, College of Biomedicine and Health, Interdisciplinary Sciences Institute, Huazhong Agricultural University, Wuhan, 430070, China.
- Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Shenzhen, 518000, 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, 518000, China.
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11
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Yin S, Lan W, Hou X, Liu Z, Xue H, Wang C, Tang GL, Cao C. Trioxacarcin A Interactions with G-Quadruplex DNA Reveal Its Potential New Targets as an Anticancer Agent. J Med Chem 2023; 66:6798-6810. [PMID: 37154782 DOI: 10.1021/acs.jmedchem.3c00178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Trioxacarcin (TXN) A was reported to be an anticancer agent through alkylation of dsDNA. G-quadruplex DNA (G4-DNA) is frequently formed in the promoter regions of oncogenes and the ends of telomerase genes, considered as promising drug targets for anticancer therapy. There are no reports about TXN A interactions with G4-DNA. Here, we tested TXN A's interactions with several G4-DNA oligos with parallel, antiparallel, or hybrid folding, respectively. We demonstrated that TXN A preferred to alkylate one flexible guanine in the loops of parallel G4-DNA. The position of the alkylated guanine is in favor of interactions of G4-DNA with TXN A. The structure of TXN A covalently bound RET G4-DNA indicated that TXN A alkylation on RET G4-DNA stabilizes the G4-DNA conformation. These studies opened a new window of how TXN A interacted with G4-DNA, which might hint a new mode of its function as an anticancer agent.
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Affiliation(s)
- Shaowen Yin
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
- University of Chinese Academy of Science, No. 19A, Yuquan Road, Shijingshan District, Beijing 100049, China
| | - Wenxian Lan
- The Core Facility Centre of CAS Center for Excellence in Molecular Plant Sciences, 300 Fengling Road, Shanghai 200032, China
| | - Xianfeng Hou
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Zhijun Liu
- National Center for Protein Science in Shanghai, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 333 Kaike Road, Shanghai 201210, China
| | - Hongjuan Xue
- National Center for Protein Science in Shanghai, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 333 Kaike Road, Shanghai 201210, China
| | - Chunxi Wang
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Gong-Li Tang
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
| | - Chunyang Cao
- State Key Laboratory of Bioorganic and Natural Product Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
- University of Chinese Academy of Science, No. 19A, Yuquan Road, Shijingshan District, Beijing 100049, China
- Collaborative Innovation Center of Chemistry for Life Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China
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12
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Wang J, Qiao J, Zheng W, Lian H. Study on the Interaction of a Peptide Targeting Specific G-Quadruplex Structures Based on Chromatographic Retention Behavior. Int J Mol Sci 2023; 24:ijms24021438. [PMID: 36674950 PMCID: PMC9866954 DOI: 10.3390/ijms24021438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/01/2023] [Accepted: 01/09/2023] [Indexed: 01/12/2023] Open
Abstract
G-quadruplexes (G4s) are of vital biological significance and G4-specific ligands with conformational selectivity show great application potential in disease treatment and biosensing. RHAU, a RNA helicase associated with AU-rich element, exerts biological functions through the mediation of G4s and has been identified to be a G4 binder. Here, we investigated the interactions between the RHAU peptide and G4s with different secondary structures using size exclusion chromatography (SEC) in association with circular dichroism (CD), ultraviolet-visible (UV-Vis) absorption, and native polyacrylamide gel electrophoresis (Native-PAGE). Spectral results demonstrated that the RHAU peptide did not break the main structure of G4s, making it more reliable for G4 structural analysis. The RHAU peptide was found to display a structural selectivity for a preferential binding to parallel G4s as reflected by the distinct chromatographic retention behaviors. In addition, the RHAU peptide exhibited different interactions with intermolecular parallel G4s and intramolecular parallel G4s, providing a novel recognition approach to G4 structures. The findings of this study enriched the insight into the binding of RHAU to G4s with various conformations. It is noteworthy that SEC technology can be easy and reliable for elucidating G4-peptide interactions, especially for a multiple G4 coexisting system, which supplied an alternative strategy to screen novel specific ligands for G4s.
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Affiliation(s)
- Ju Wang
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Junqin Qiao
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
- Correspondence: (J.Q.); (H.L.)
| | - Weijuan Zheng
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
| | - Hongzhen Lian
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering and Center of Materials Analysis, Nanjing University, 163 Xianlin Avenue, Nanjing 210023, China
- Correspondence: (J.Q.); (H.L.)
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13
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Structural Polymorphism of Guanine Quadruplex-Containing Regions in Human Promoters. Int J Mol Sci 2022; 23:ijms232416020. [PMID: 36555662 PMCID: PMC9786302 DOI: 10.3390/ijms232416020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Revised: 12/05/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022] Open
Abstract
Intramolecular guanine quadruplexes (G4s) are non-canonical nucleic acid structures formed by four guanine (G)-rich tracts that assemble into a core of stacked planar tetrads. G4-forming DNA sequences are enriched in gene promoters and are implicated in the control of gene expression. Most G4-forming DNA contains more G residues than can simultaneously be incorporated into the core resulting in a variety of different possible G4 structures. Although this kind of structural polymorphism is well recognized in the literature, there remain unanswered questions regarding possible connections between G4 polymorphism and biological function. Here we report a detailed bioinformatic survey of G4 polymorphism in human gene promoter regions. Our analysis is based on identifying G4-containing regions (G4CRs), which we define as stretches of DNA in which every residue can form part of a G4. We found that G4CRs with higher degrees of polymorphism are more tightly clustered near transcription sites and tend to contain G4s with shorter loops and bulges. Furthermore, we found that G4CRs with well-characterized biological functions tended to be longer and more polymorphic than genome-wide averages. These results represent new evidence linking G4 polymorphism to biological function and provide new criteria for identifying biologically relevant G4-forming regions from genomic data.
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14
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G-Quadruplex Formed by the Promoter Region of the hTERT Gene: Structure-Driven Effects on DNA Mismatch Repair Functions. Biomedicines 2022; 10:biomedicines10081871. [PMID: 36009419 PMCID: PMC9405553 DOI: 10.3390/biomedicines10081871] [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: 06/20/2022] [Revised: 07/25/2022] [Accepted: 07/29/2022] [Indexed: 11/17/2022] Open
Abstract
G-quadruplexes (G4s) are a unique class of noncanonical DNAs that play a key role in cellular processes and neoplastic transformation. Herein, we focused on the promoter region of human TERT oncogene, whose product is responsible for the immortality of cancer cells. It has been shown by chemical probing and spectroscopic methods that synthetic 96-nt DNAs modeling the wild-type G-rich strand of the hTERT promoter and its variants with G>A point substitutions corresponding to somatic driver mutations fold into three stacked parallel G4s with sites of local G4 destabilization caused by G>A substitutions in the G4 motif. These models were used to elucidate how the hTERT multiG4 affects the binding affinity and functional responses of two key proteins, MutS and MutL, involved in the initial stage of DNA mismatch repair (MMR) in Escherichiacoli and Neisseriagonorrhoeae with different MMR mechanisms. We have shown for the first time that (i) point substitutions do not affect the effective binding of these proteins to the hTERT G4 structure, and (ii) the endonuclease activity of MutL from N. gonorrhoeae is significantly suppressed by the stable G4 scaffold. It is likely that some of the genomic instability associated with G4 may be related to the blockage of human intrinsic methyl-independent MMR attempting to operate near G4 structures.
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15
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High-throughput techniques enable advances in the roles of DNA and RNA secondary structures in transcriptional and post-transcriptional gene regulation. Genome Biol 2022; 23:159. [PMID: 35851062 PMCID: PMC9290270 DOI: 10.1186/s13059-022-02727-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 07/07/2022] [Indexed: 12/27/2022] Open
Abstract
The most stable structure of DNA is the canonical right-handed double helix termed B DNA. However, certain environments and sequence motifs favor alternative conformations, termed non-canonical secondary structures. The roles of DNA and RNA secondary structures in transcriptional regulation remain incompletely understood. However, advances in high-throughput assays have enabled genome wide characterization of some secondary structures. Here, we describe their regulatory functions in promoters and 3’UTRs, providing insights into key mechanisms through which they regulate gene expression. We discuss their implication in human disease, and how advances in molecular technologies and emerging high-throughput experimental methods could provide additional insights.
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16
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Monsen RC, Maguire JM, DeLeeuw LW, Chaires JB, Trent JO. Drug discovery of small molecules targeting the higher-order hTERT promoter G-quadruplex. PLoS One 2022; 17:e0270165. [PMID: 35709230 PMCID: PMC9202945 DOI: 10.1371/journal.pone.0270165] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/03/2022] [Indexed: 12/15/2022] Open
Abstract
DNA G-quadruplexes (G4s) are now widely accepted as viable targets in the pursuit of anticancer therapeutics. To date, few small molecules have been identified that exhibit selectivity for G4s over alternative forms of DNA, such as the ubiquitous duplex. We posit that the lack of current ligand specificity arises for multiple reasons: G4 atomic models are often small, monomeric, single quadruplex structures with few or no druggable pockets; targeting G-tetrad faces frequently results in the enrichment of extended electron-deficient polyaromatic end-pasting scaffolds; and virtual drug discovery efforts often under-sample chemical search space. We show that by addressing these issues we can enrich for non-standard molecular templates that exhibit high selectivity towards G4s over other forms of DNA. We performed an extensive virtual screen against the higher-order hTERT core promoter G4 that we have previously characterized, targeting 12 of its unique loop and groove pockets using libraries containing 40 million drug-like compounds for each screen. Using our drug discovery funnel approach, which utilizes high-throughput fluorescence thermal shift assay (FTSA) screens, microscale thermophoresis (MST), and orthogonal biophysical methods, we have identified multiple unique G4 binding scaffolds. We subsequently used two rounds of catalogue-based SAR to increase the affinity of a disubstituted 2-aminoethyl-quinazoline that stabilizes the higher-order hTERT G-quadruplex by binding across its G4 junctional sites. We show selectivity of its binding affinity towards hTERT is virtually unaffected in the presence of near-physiological levels of duplex DNA, and that this molecule downregulates hTERT transcription in breast cancer cells.
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Affiliation(s)
- Robert C. Monsen
- UofL Health Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Jon M. Maguire
- UofL Health Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Lynn W. DeLeeuw
- UofL Health Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Jonathan B. Chaires
- UofL Health Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (JBC); (JOT)
| | - John O. Trent
- UofL Health Brown Cancer Center, University of Louisville, Louisville, Kentucky, United States of America
- Department of Medicine, University of Louisville, Louisville, Kentucky, United States of America
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, Kentucky, United States of America
- * E-mail: (JBC); (JOT)
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17
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Meier-Stephenson V. G4-quadruplex-binding proteins: review and insights into selectivity. Biophys Rev 2022; 14:635-654. [PMID: 35791380 PMCID: PMC9250568 DOI: 10.1007/s12551-022-00952-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/04/2022] [Indexed: 02/06/2023] Open
Abstract
There are over 700,000 putative G4-quadruplexes (G4Qs) in the human genome, found largely in promoter regions, telomeres, and other regions of high regulation. Growing evidence links their presence to functionality in various cellular processes, where cellular proteins interact with them, either stabilizing and/or anchoring upon them, or unwinding them to allow a process to proceed. Interest in understanding and manipulating the plethora of processes regulated by these G4Qs has spawned a new area of small-molecule binder development, with attempts to mimic and block the associated G4-binding protein (G4BP). Despite the growing interest and focus on these G4Qs, there is limited data (in particular, high-resolution structural information), on the nature of these G4Q-G4BP interactions and what makes a G4BP selective to certain G4Qs, if in fact they are at all. This review summarizes the current literature on G4BPs with regards to their interactions with G4Qs, providing groupings for binding mode, drawing conclusions around commonalities and highlighting information on specific interactions where available.
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Affiliation(s)
- Vanessa Meier-Stephenson
- Department of Medicine, Division of Infectious Diseases, University of Alberta, Edmonton, AB Canada
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB Canada
- Li Ka Shing Institute of Virology, University of Alberta, Edmonton, AB Canada
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18
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Thermally Induced Transitions of d(G4T4G3) Quadruplexes Can Be Described as Kinetically Driven Processes. Life (Basel) 2022; 12:life12060825. [PMID: 35743856 PMCID: PMC9225023 DOI: 10.3390/life12060825] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 11/16/2022] Open
Abstract
DNA sequences that are rich in guanines and can form four-stranded structures are called G-quadruplexes. Due to the growing evidence that they may play an important role in several key biological processes, the G-quadruplexes have captured the interest of several researchers. G-quadruplexes may form in the presence of different metal cations as polymorphic structures formed in kinetically governed processes. Here we investigate a complex polymorphism of d(G4T4G3) quadruplexes at different K+ concentrations. We show that population size of different d(G4T4G3) quadruplex conformations can be manipulated by cooling rate and/or K+ concentration. We use a kinetic model to describe data obtained from DSC, CD and UV spectroscopy and PAGE experiments. Our model is able to describe the observed thermally induced conformational transitions of d(G4T4G3) quadruplexes at different K+ concentrations.
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19
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Emerging mechanisms of telomerase reactivation in cancer. Trends Cancer 2022; 8:632-641. [PMID: 35568649 PMCID: PMC7614490 DOI: 10.1016/j.trecan.2022.03.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 12/17/2022]
Abstract
Mutations in the promoter of human telomerase reverse transcriptase (hTERT) result in hyperactivation of hTERT. Notably, all mutations are G>A transitions, frequently found in a wide range of cancer types, and causally associated with cancer progression. Initially, the mutations were understood to reactivate hTERT by generating novel E26 transformation-specific (ETS) binding sites. Recent work reveals the role of DNA secondary structure G-quadruplexes, telomere binding factor(s), and chromatin looping in hTERT regulation. Here, we discuss these emerging findings in relation to the clinically significant promoter mutations to provide a broader understanding of the context-dependent outcomes that result in hTERT activation in normal and pathogenic conditions.
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20
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Monsen RC, DeLeeuw LW, Dean WL, Gray RD, Chakravarthy S, Hopkins JB, Chaires JB, Trent JO. Long promoter sequences form higher-order G-quadruplexes: an integrative structural biology study of c-Myc, k-Ras and c-Kit promoter sequences. Nucleic Acids Res 2022; 50:4127-4147. [PMID: 35325198 PMCID: PMC9023277 DOI: 10.1093/nar/gkac182] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/03/2022] [Accepted: 03/21/2022] [Indexed: 12/15/2022] Open
Abstract
We report on higher-order G-quadruplex structures adopted by long promoter sequences obtained by an iterative integrated structural biology approach. Our approach uses quantitative biophysical tools (analytical ultracentrifugation, small-angle X-ray scattering, and circular dichroism spectroscopy) combined with modeling and molecular dynamics simulations, to derive self-consistent structural models. The formal resolution of our approach is 18 angstroms, but in some cases structural features of only a few nucleotides can be discerned. We report here five structures of long (34-70 nt) wild-type sequences selected from three cancer-related promoters: c-Myc, c-Kit and k-Ras. Each sequence studied has a unique structure. Three sequences form structures with two contiguous, stacked, G-quadruplex units. One longer sequence from c-Myc forms a structure with three contiguous stacked quadruplexes. A longer c-Kit sequence forms a quadruplex-hairpin structure. Each structure exhibits interfacial regions between stacked quadruplexes or novel loop geometries that are possible druggable targets. We also report methodological advances in our integrated structural biology approach, which now includes quantitative CD for counting stacked G-tetrads, DNaseI cleavage for hairpin detection and SAXS model refinement. Our results suggest that higher-order quadruplex assemblies may be a common feature within the genome, rather than simple single quadruplex structures.
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Affiliation(s)
- Robert C Monsen
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Lynn W DeLeeuw
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - William L Dean
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Robert D Gray
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Srinivas Chakravarthy
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Jesse B Hopkins
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological, Chemical, and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Jonathan B Chaires
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
| | - John O Trent
- UofL Health Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
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21
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Lomidze L, Yang M, Khutsishvili D, Metreveli N, Musier-Forsyth K, Kankia B. Structure of Tetrahelical DNA Homopolymers Supports Quadruplex World Hypothesis. ACS OMEGA 2022; 7:4311-4316. [PMID: 35155924 PMCID: PMC8829921 DOI: 10.1021/acsomega.1c06026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/31/2021] [Indexed: 06/14/2023]
Abstract
We previously reported a tetrahelical monomolecular architecture of DNA, tmDNA, which employs G-quartets and an all-parallel GGGTGGGTGGGTGGG (G3T) quadruplex as the repeating unit. Based on thermodynamic and kinetic studies, we proposed that covalently joined (G3T) n units formed an uninterrupted programmable homopolymer; however, structural evidence for the tmDNA architecture was lacking. Here, we used NMR spectroscopy of wild-type and single-inosine-substituted constructs to characterize both monomolecular (G3T)2 and bimolecular quadruplex-Mg-coupled versions of tmDNA. The NMR results support an architecture consisting of uninterrupted stacked G-tetrads in both the monomolecular constructs and bimolecular assemblies. Taken together, these data support the formation of a stable programmable homopolymeric tmDNA architecture, which may have been a precursor to the modern-day Watson-Crick DNA duplex.
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Affiliation(s)
- Levan Lomidze
- Institute of Biophysics, Ilia State University, Tbilisi 0162, Republic of Georgia
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mengkun Yang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - David Khutsishvili
- Institute of Biophysics, Ilia State University, Tbilisi 0162, Republic of Georgia
| | - Nunu Metreveli
- Institute of Biophysics, Ilia State University, Tbilisi 0162, Republic of Georgia
| | - Karin Musier-Forsyth
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Besik Kankia
- Institute of Biophysics, Ilia State University, Tbilisi 0162, Republic of Georgia
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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22
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Liu YC, Yang DY, Sheu SY. Insights into the free energy landscape and salt-controlled mechanism of the conformational conversions between human telomeric G-quadruplex structures. Int J Biol Macromol 2021; 191:230-242. [PMID: 34536474 DOI: 10.1016/j.ijbiomac.2021.09.057] [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: 06/29/2021] [Revised: 08/23/2021] [Accepted: 09/10/2021] [Indexed: 12/16/2022]
Abstract
G-quadruplexes have become attractive drug targets in cancer therapy. However, due to the polymorphism of G-quadruplex structures, it is difficult to experimentally verify the relevant structures of multiple intermediates and transition states in dynamic equilibrium. Hence, understanding the mechanism by which structural conversions of G-quadruplexes occur is still challenging. We conducted targeted molecular dynamics simulation with umbrella sampling to investigate how salt affects the conformational conversion of human telomeric G-quadruplex. Our results explore a unique view into the structures and energy barrier of the intermediates and transition states in the interconversion process. The pathway of G-quadruplex conformational interconversion was mapped out by a free energy landscape, consisting of branched parallel pathways with multiple energy basins. We propose a salt-controlled mechanism that as the salt concentration increases, the conformational conversion mechanism switches from multi-pathway folding to sequential folding pathways. The hybrid-I and hybrid-II structures are intermediates in the basket-propeller transformation. In high-salt solutions, the conformational conversion upon K+ binding is more feasible than upon Na+ binding. The free energy barrier for conformational conversions ranges from 1.6 to 4.6 kcal/mol. Our work will be beneficial in developing anticancer agents.
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Affiliation(s)
- Yu-Cheng Liu
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei 112, Taiwan
| | - Dah-Yen Yang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan.
| | - Sheh-Yi Sheu
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei 112, Taiwan; Department of Life Sciences and Institute of Genome Sciences, National Yang Ming Chiao Tung University, Taipei 112, Taiwan.
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23
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Grün JT, Schwalbe H. Folding dynamics of polymorphic G-quadruplex structures. Biopolymers 2021; 113:e23477. [PMID: 34664713 DOI: 10.1002/bip.23477] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 12/14/2022]
Abstract
G-quadruplexes (G4), found in numerous places within the human genome, are involved in essential processes of cell regulation. Chromosomal DNA G4s are involved for example, in replication and transcription as first steps of gene expression. Hence, they influence a plethora of downstream processes. G4s possess an intricate structure that differs from canonical B-form DNA. Identical DNA G4 sequences can adopt multiple long-lived conformations, a phenomenon known as G4 polymorphism. A detailed understanding of the molecular mechanisms that drive G4 folding is essential to understand their ambivalent regulatory roles. Disentangling the inherent dynamic and polymorphic nature of G4 structures thus is key to unravel their biological functions and make them amenable as molecular targets in novel therapeutic approaches. We here review recent experimental approaches to monitor G4 folding and discuss structural aspects for possible folding pathways. Substantial progress in the understanding of G4 folding within the recent years now allows drawing comprehensive models of the complex folding energy landscape of G4s that we herein evaluate based on computational and experimental evidence.
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Affiliation(s)
- J Tassilo Grün
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot, Israel
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Johann Wolfgang Goethe-University, Frankfurt/M, Germany.,Center for Biomolecular Magnetic Resonance (BMRZ), Johann Wolfgang Goethe-University Frankfurt, Frankfurt/M, Germany
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24
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Williams AM, Poudyal RR, Bevilacqua PC. Long Tracts of Guanines Drive Aggregation of RNA G-Quadruplexes in the Presence of Spermine. Biochemistry 2021; 60:2715-2726. [PMID: 34448586 DOI: 10.1021/acs.biochem.1c00467] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
G-Quadruplexes (GQs) are compact, stable structures in DNA and RNA comprised of two or more tiers of quartets whose G-rich motif of tracts of two or more G's occurs commonly within genomes and transcriptomes. While thermodynamically stable in vitro, these structures remain difficult to study in vivo. One approach to understanding GQ in vivo behavior is to test whether conditions and molecules found in cells facilitate their folding. Polyamines are biogenic polycations that interact with RNA. Among common polyamines, spermine contains the highest charge and is found in eukaryotes, making it a good candidate for association with high-charge density nucleic acid structures like GQs. Using a variety of techniques, including ultraviolet-detected thermal denaturation, circular dichroism, size exclusion chromatography, and confocal microscopy, on an array of quadruplex sequence variants, we find that eukaryotic biological concentrations of spermine induce microaggregation of three-tiered G-rich sequences, but not of purely two-tiered structures, although higher spermine concentrations induce aggregation of even these. The formation of microaggregates can also be induced by addition of as little as a single G to a two-tiered structure; moreover, they form at biological temperatures, are sensitive to salt, and can form in the presence of at least some flanking sequence. Notably, GQ aggregation is not observed under prokaryotic-like conditions of no spermine and higher NaCl concentrations. The sequence, polyamine, and salt specificity of microaggregation reported herein have implications for the formation and stability of G-rich nucleic acid aggregates in vivo and for functional roles for understudied GQ sequences with only two quadruplex tiers.
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Affiliation(s)
- Allison M Williams
- Department of Biochemistry, Microbiology, and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Raghav R Poudyal
- Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.,Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Philip C Bevilacqua
- Department of Biochemistry, Microbiology, and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.,Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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25
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Santos T, Miranda A, Campello MPC, Paulo A, Salgado G, Cabrita EJ, Cruz C. Recognition of nucleolin through interaction with RNA G-quadruplex. Biochem Pharmacol 2021; 189:114208. [PMID: 32860827 DOI: 10.1016/j.bcp.2020.114208] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/21/2020] [Accepted: 08/24/2020] [Indexed: 12/12/2022]
Abstract
The development of novel biomarkers for early-stage diagnosis of prostate cancer (PCa) has attracted the attention of researchers in the last decade. Nucleolin (NCL) has emerged as a possible biomarker of PCa due to its high expression levels in the surface of PCa cells and affinity towards parallel G4s since it contains four RNA-binding domains (RBDs). Herein, we developed a novel strategy based on a microfluidic platform for the detection of NCL in biological samples, such as human plasma. The RNA G4 (rG4) sequence found in human precursor microRNA 92b (pre-miR-92b) was used as a molecular recognition probe since it forms a single dominant parallel rG4 conformation in the presence of 0.1 mM K+ as confirmed by NMR spectroscopy. The additional stability of the rG4 structure was provided by the acridine orange derivative ligand C8, which stabilizes the pre-miR-92b rG4 structure, as denoted by an increase in more than 30 °C of its melting temperature. FRET-melting assay revealed a remarkable synergistic effect of NCL RBD1,2 and C8 on the stabilization of the pre-miR-92b rG4. The binding of pre-miR-92b to NCL RBD1,2 was determined by in silico studies, which revealed a binding pocket formed by a 12-residue linker between RBD1 and RBD2. Both, pre-miR-92b rG4 and pre-miR-92b rG4/C8 complex demonstrated high affinity towards NCL RBD1,2, as proved by fluorimetric titrations (KD range between 10-12 and 10-9 M). The stability and nuclease resistance of pre-miR-92b rG4 and pre-miR-92b rG4/C8 complex were evaluated as molecular recognition probes to capture and detect NCL. Finally, the microfluidic platform detects NCL in complex biological samples, such as human plasma. Overall, this work demonstrates the usefulness of the microfluidic platform based on the pre-miR-92b to detect NCL and the possibility to be used as a valuable biomedical tool in PCa diagnosis.
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Affiliation(s)
- Tiago Santos
- CICS-UBI - Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, Covilhã, Portugal
| | - André Miranda
- CICS-UBI - Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, Covilhã, Portugal
| | - Maria P C Campello
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - António Paulo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Gilmar Salgado
- Univ. Bordeaux, ARNA Laboratory, INSERM, U1212, CNRS UMR 5320, IECB, F-33600 Pessac, France
| | - Eurico J Cabrita
- UCIBIO, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica 2829-516, Portugal
| | - Carla Cruz
- CICS-UBI - Centro de Investigação em Ciências da Saúde, Universidade da Beira Interior, Av. Infante D. Henrique, Covilhã, Portugal.
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26
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Sharma S, Mukherjee AK, Roy SS, Bagri S, Lier S, Verma M, Sengupta A, Kumar M, Nesse G, Pandey DP, Chowdhury S. Human telomerase is directly regulated by non-telomeric TRF2-G-quadruplex interaction. Cell Rep 2021; 35:109154. [PMID: 34010660 PMCID: PMC7611063 DOI: 10.1016/j.celrep.2021.109154] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/15/2021] [Accepted: 04/28/2021] [Indexed: 12/16/2022] Open
Abstract
Human telomerase reverse transcriptase (hTERT) remains suppressed in most normal somatic cells. Resulting erosion of telomeres leads eventually to replicative senescence. Reactivation of hTERT maintains telomeres and triggers progression of >90% of cancers. However, any direct causal link between telomeres and telomerase regulation remains unclear. Here, we show that the telomere-repeat-binding-factor 2 (TRF2) binds hTERT promoter G-quadruplexes and recruits the polycomb-repressor EZH2/PRC2 complex. This is causal for H3K27 trimethylation at the hTERT promoter and represses hTERT in cancer as well as normal cells. Two highly recurrent hTERT promoter mutations found in many cancers, including ∼83% glioblastoma multiforme, that are known to destabilize hTERT promoter G-quadruplexes, showed loss of TRF2 binding in patient-derived primary glioblastoma multiforme cells. Ligand-induced G-quadruplex stabilization restored TRF2 binding, H3K27-trimethylation, and hTERT re-suppression. These results uncover a mechanism of hTERT regulation through a telomeric factor, implicating telomere-telomerase molecular links important in neoplastic transformation, aging, and regenerative therapy.
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Affiliation(s)
- Shalu Sharma
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Ananda Kishore Mukherjee
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Shuvra Shekhar Roy
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Sulochana Bagri
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Silje Lier
- Department of Microbiology, Oslo University Hospital, Oslo, Norway; Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
| | - Meenakshi Verma
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Antara Sengupta
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Manish Kumar
- Imaging Facility, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India
| | - Gaute Nesse
- Department of Microbiology, Oslo University Hospital, Oslo, Norway
| | | | - Shantanu Chowdhury
- Integrative and Functional Biology Unit, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India; GNR Knowledge Centre for Genome and Informatics, CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India; CSIR-Institute of Genomics and Integrative Biology, New Delhi 110025, India.
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27
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Grün JT, Blümler A, Burkhart I, Wirmer-Bartoschek J, Heckel A, Schwalbe H. Unraveling the Kinetics of Spare-Tire DNA G-Quadruplex Folding. J Am Chem Soc 2021; 143:6185-6193. [PMID: 33872503 DOI: 10.1021/jacs.1c01089] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The folding of DNA G-quadruplexes (G4) is essential to regulate expression of oncogenes and involves polymorphic long-lived intermediate states. G4 formation requires four G-tracts, but human gene-promoters often contain multiple G-tracts that act as spare-tires. These additional G-tracts are highly conserved and add multiple layers of functional complexity, as they are crucial to maintain G4 function after oxidative damage. Herein, we unravel the folding dynamics of the G4 sequence containing five G-tracts from cMYC, the major proliferation-driving oncogene. We devise a general method to induce folding at constant experimental conditions using a photochemical trapping strategy. Our data dissect the individual kinetics and thermodynamics of the spare-tire mechanism of cMYC-G4.
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Affiliation(s)
- J Tassilo Grün
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Anja Blümler
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Ines Burkhart
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Julia Wirmer-Bartoschek
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Goethe University Frankfurt am Main, Frankfurt 60323, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt am Main, Frankfurt 60323, Germany
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28
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Harkness RW, Hennecker C, Grün JT, Blümler A, Heckel A, Schwalbe H, Mittermaier AK. Parallel reaction pathways accelerate folding of a guanine quadruplex. Nucleic Acids Res 2021; 49:1247-1262. [PMID: 33469659 PMCID: PMC7897495 DOI: 10.1093/nar/gkaa1286] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 12/21/2020] [Accepted: 12/27/2020] [Indexed: 02/07/2023] Open
Abstract
G-quadruplexes (G4s) are four-stranded, guanine-rich nucleic acid structures that can influence a variety of biological processes such as the transcription and translation of genes and DNA replication. In many cases, a single G4-forming nucleic acid sequence can adopt multiple different folded conformations that interconvert on biologically relevant timescales, entropically stabilizing the folded state. The coexistence of different folded conformations also suggests that there are multiple pathways leading from the unfolded to the folded state ensembles, potentially modulating the folding rate and biological activity. We have developed an experimental method for quantifying the contributions of individual pathways to the folding of conformationally heterogeneous G4s that is based on mutagenesis, thermal hysteresis kinetic experiments and global analysis, and validated our results using photocaged kinetic NMR experiments. We studied the regulatory Pu22 G4 from the c-myc oncogene promoter, which adopts at least four distinct folded isomers. We found that the presence of four parallel pathways leads to a 2.5-fold acceleration in folding; that is, the effective folding rate from the unfolded to folded ensembles is 2.5 times as large as the rate constant for the fastest individual pathway. Since many G4 sequences can adopt many more than four isomers, folding accelerations of more than an order of magnitude are possible via this mechanism.
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Affiliation(s)
- Robert W Harkness
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.,Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
| | | | - J Tassilo Grün
- Institute for Organic Chemistry and Chemical Biology, Goethe University, Frankfurt am Main 60438, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt am Main 60438, Germany
| | - Anja Blümler
- Institute for Organic Chemistry and Chemical Biology, Goethe University, Frankfurt am Main 60438, Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical Biology, Goethe University, Frankfurt am Main 60438, Germany
| | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology, Goethe University, Frankfurt am Main 60438, Germany.,Center of Biomolecular Magnetic Resonance (BMRZ), Goethe University, Frankfurt am Main 60438, Germany
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29
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Marchand A, Beauvineau C, Teulade-Fichou MP, Zenobi R. Competition of Ligands and the 18-mer Binding Domain of the RHAU Helicase for G-Quadruplexes: Orthosteric or Allosteric Binding Mechanism? Chemistry 2021; 27:1113-1121. [PMID: 33617136 DOI: 10.1002/chem.202004040] [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: 09/04/2020] [Revised: 10/12/2020] [Indexed: 01/12/2023]
Abstract
Stabilizing the DNA and RNA structures known as G-quadruplexes (G4s) using specific ligands is a strategy that has been proposed to fight cancer. However, although G-quadruplex:ligand (G4:L) interactions have often been investigated, whether or not ligands are able to disrupt G-quadruplex:protein (G4:P) interactions remains poorly studied. In this study, using native mass spectrometry, we have investigated ternary G4:L:P complexes formed by G4s, some of the highest affinity ligands, and the binding domain of the RHAU helicase. Our results suggest that RHAU binds not only preferentially to parallel G4s, but also to free external G-quartets. We also found that, depending on the G4, ligands could prevent the binding of the peptide, either by direct competition for the binding sites (orthosteric inhibition) or by inducing conformational changes (allosteric inhibition). Notably, the ligand Cu-ttpy (ttpy=4'-tolyl-2,2':6',2''-terpyridine) induced a conformational change that increased the binding of the peptide. This study illustrates that it is important to not only characterize drug-target interactions, but also how the binding to other partners is affected.
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Affiliation(s)
- Adrien Marchand
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 3, 8093, Zürich, Switzerland
| | - Claire Beauvineau
- PSL Research University, CNRS-UMR 9187, INSERM U1196, Institut Curie, 91405, Orsay, France.,CNRS-UMR 9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Marie-Paule Teulade-Fichou
- PSL Research University, CNRS-UMR 9187, INSERM U1196, Institut Curie, 91405, Orsay, France.,CNRS-UMR 9187, INSERM U1196, Université Paris Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 3, 8093, Zürich, Switzerland
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30
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Summart R, Thaichana P, Supan J, Meepowpan P, Lee TR, Tuntiwechapikul W. Superiority of an Asymmetric Perylene Diimide in Terms of Hydrosolubility, G-Quadruplex Binding, Cellular Uptake, and Telomerase Inhibition in Prostate Cancer Cells. ACS OMEGA 2020; 5:29733-29745. [PMID: 33251409 PMCID: PMC7689663 DOI: 10.1021/acsomega.0c03505] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 11/05/2020] [Indexed: 05/11/2023]
Abstract
Perylene diimide (PDI) derivatives have been studied as G-quadruplex ligands that suppress telomerase activity by facilitating G-quadruplex formation of telomeric DNA and the hTERT promoter. PIPER, the prototypical PDI, reduces telomerase activity in lung and prostate cancer cells, leading to telomere shortening and cellular senescence of these cells. However, PIPER suffers from poor hydrosolubility and the propensity to aggregate at neutral pH. In this report, we synthesized a new asymmetric PDI, aPDI-PHis, which maintains one N-ethyl piperidine side chain of PIPER and has histidine as another side chain. The results show that aPDI-PHis is superior to its symmetric counterparts, PIPER and PDI-His, in terms of hydrosolubility, G-quadruplex binding, cellular uptake, and telomerase inhibition in prostate cancer cells. These results suggest that one N-ethyl piperidine side chain of PDI is sufficient for G-quadruplex binding, while another side chain can be tuned to elicit desirable properties. These findings might lead to better PDIs for use as anticancer drugs.
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Affiliation(s)
- Ratasark Summart
- Department
of Biochemistry, Faculty of Medicine, Chiang
Mai University, 110 Intavaroros Road, Chiang Mai 50200, Thailand
| | - Pak Thaichana
- Department
of Biochemistry, Faculty of Medicine, Chiang
Mai University, 110 Intavaroros Road, Chiang Mai 50200, Thailand
| | - Jutharat Supan
- Department
of Biochemistry, Faculty of Medicine, Chiang
Mai University, 110 Intavaroros Road, Chiang Mai 50200, Thailand
| | - Puttinan Meepowpan
- Department
of Chemistry, Faculty of Science, Chiang
Mai University, Chiang
Mai 50200, Thailand
| | - T. Randall Lee
- Department
of Chemistry and the Texas Center for Superconductivity, University of Houston, Houston, Texas 77204-5003, United States
| | - Wirote Tuntiwechapikul
- Department
of Biochemistry, Faculty of Medicine, Chiang
Mai University, 110 Intavaroros Road, Chiang Mai 50200, Thailand
- . Tel: +66-53-945323.
Fax: +66-53-894031
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31
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Tan DJY, Winnerdy FR, Lim KW, Phan AT. Coexistence of two quadruplex-duplex hybrids in the PIM1 gene. Nucleic Acids Res 2020; 48:11162-11171. [PMID: 32976598 PMCID: PMC7641742 DOI: 10.1093/nar/gkaa752] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 08/26/2020] [Accepted: 08/31/2020] [Indexed: 12/31/2022] Open
Abstract
The triple-negative breast cancer (TNBC), a subtype of breast cancer which lacks of targeted therapies, exhibits a poor prognosis. It was shown recently that the PIM1 oncogene is highly related to the proliferation of TNBC cells. A quadruplex-duplex hybrid (QDH) forming sequence was recently found to exist near the transcription start site of PIM1. This structure could be an attractive target for regulation of the PIM1 gene expression and thus the treatment of TNBC. Here, we present the solution structures of two QDHs that could coexist in the human PIM1 gene. Form 1 is a three-G-tetrad-layered (3+1) G-quadruplex containing a propeller loop, a lateral loop and a stem-loop made up of three G•C Watson-Crick base pairs. On the other hand, Form 2 is an anti-parallel G-quadruplex comprising two G-tetrads and a G•C•G•C tetrad; the structure has three lateral loops with the middle stem-loop made up of two Watson-Crick G•C base pairs. These structures provide valuable information for the design of G-quadruplex-specific ligands for PIM1 transcription regulation.
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Affiliation(s)
- Derrick J Y Tan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Kah Wai Lim
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
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32
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Ngoc Nguyen TQ, Lim KW, Phan AT. Duplex formation in a G-quadruplex bulge. Nucleic Acids Res 2020; 48:10567-10575. [PMID: 32960213 PMCID: PMC7544226 DOI: 10.1093/nar/gkaa738] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/21/2020] [Accepted: 08/31/2020] [Indexed: 01/05/2023] Open
Abstract
Beyond the consensus definition of G-quadruplex-forming motifs with tracts of continuous guanines, G-quadruplexes harboring bulges in the G-tetrad core are prevalent in the human genome. Here, we study the incorporation of a duplex hairpin within a bulge of a G-quadruplex. The NMR solution structure of a G-quadruplex containing a duplex bulge was resolved, revealing the structural details of the junction between the duplex bulge and the G-quadruplex. Unexpectedly, instead of an orthogonal connection the duplex stem was observed to stack below the G-quadruplex forming a unique quadruplex–duplex junction. Breaking up of the immediate base pair step at the junction, coupled with a narrowing of the duplex groove within the context of the bulge, led to a progressive transition between the quadruplex and duplex segments. This study revealed that a duplex bulge can be formed at various positions of a G-quadruplex scaffold. In contrast to a non-structured bulge, the stability of a G-quadruplex slightly increases with an increase in the duplex bulge size. A G-quadruplex structure containing a duplex bulge of up to 33 nt in size was shown to form, which was much larger than the previously reported 7-nt bulge. With G-quadruplexes containing duplex bulges representing new structural motifs with potential biological significance, our findings would broaden the definition of potential G-quadruplex-forming sequences.
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Affiliation(s)
- Thi Quynh Ngoc Nguyen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Kah Wai Lim
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
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33
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Suseela YV, Satha P, Murugan NA, Govindaraju T. Recognition of G-quadruplex topology through hybrid binding with implications in cancer theranostics. Theranostics 2020; 10:10394-10414. [PMID: 32929356 PMCID: PMC7482797 DOI: 10.7150/thno.48675] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/09/2020] [Indexed: 12/19/2022] Open
Abstract
The selective recognition and imaging of oncogene specific G-quadruplex (GQ) structures holds great promise in the development of diagnostic therapy (theranostics) for cancer and has been challenging due to their structural dynamics and diversity. We report selective recognition of GQ by a small molecule through unique hybrid loop stacking and groove binding mode with turn on far-red fluorescence response and anticancer activity demonstrating the potential implications for GQ-targeted cancer theranostics. Methods: Biophysical investigation reveal the turn on far-red emission property of TGP18 for selective recognition of GQ. In cellulo studies including DNA damage and oxidative stress evaluation guided us to perform in vitro (3D spheroid) and in vivo (xenograft mice model) anti-cancer activity, and tumor tissue imaging to assess the theranostic potential of TGP18. Results: Neocuproine-based far-red turn on fluorescence probe TGP18 shows GQ-to-duplex selectivity and specifically recognizes BCL-2 GQ with high affinity through a unique hybrid binding mode involving loop-stacking and groove interactions. Our study reveals that the selective recognition originating from the distinct loop structure of GQ that alters the overall probe interaction and binding affinity. TGP18 binding to anti-apoptotic BCL-2 GQ ablates the pro-survival function and elicit anti-cancer activity by inducing apoptosis in cancer cells. We deciphered that inhibition of BCL-2 transcription synergized with signaling cascade of nucleolar stress, DNA damage and oxidative stress in triggering apoptosis signaling pathway. Conclusion: Intervention of GQ mediated lethality by TGP18 has translated into anti-cancer activity in both in vitro 3D spheroid culture and in vivo xenograft models of lung and breast cancer with superior efficacy for the former. In vivo therapeutic efficacy supplemented with tumor 3D spheroid and tissue imaging potential define the role of TGP18 in GQ-targeted cancer theranostics.
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34
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Ahmed A, Angell R, Oxenford S, Worthington J, Williams N, Barton N, Fowler TG, O’Flynn DE, Sunose M, McConville M, Vo T, Wilson WD, Karim SA, Morton JP, Neidle S. Asymmetrically Substituted Quadruplex-Binding Naphthalene Diimide Showing Potent Activity in Pancreatic Cancer Models. ACS Med Chem Lett 2020; 11:1634-1644. [PMID: 32832034 PMCID: PMC7429975 DOI: 10.1021/acsmedchemlett.0c00317] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 07/16/2020] [Indexed: 12/13/2022] Open
Abstract
Targeting of genomic quadruplexes is an approach to treating complex human cancers. We describe a series of tetra-substituted naphthalene diimide (ND) derivatives with a phenyl substituent directly attached to the ND core. The lead compound (SOP1812) has 10 times superior cellular and in vivo activity compared with previous ND compounds and nanomolar binding to human quadruplexes. The pharmacological properties of SOP1812 indicate good bioavailability, which is consistent with the in vivo activity in xenograft and genetic models for pancreatic cancer. Transcriptome analysis shows that it down-regulates several cancer gene pathways, including Wnt/β-catenin signaling.
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Affiliation(s)
- Ahmed
A. Ahmed
- School
of Pharmacy, University College London, London WC1N 1AX, United Kingdom
| | - Richard Angell
- School
of Pharmacy, University College London, London WC1N 1AX, United Kingdom
| | - Sally Oxenford
- School
of Pharmacy, University College London, London WC1N 1AX, United Kingdom
| | - Jenny Worthington
- Axis
Bio Discovery Services, Ltd., Coleraine, Northern Ireland BT51 3RP, United Kingdom
| | - Nicole Williams
- Axis
Bio Discovery Services, Ltd., Coleraine, Northern Ireland BT51 3RP, United Kingdom
| | - Naomi Barton
- Sygnature
Discovery Limited, Nottingham NG1 1GR, United Kingdom
| | | | | | - Mihiro Sunose
- Sygnature
Discovery Limited, Nottingham NG1 1GR, United Kingdom
| | | | - Tam Vo
- Department
of Chemistry and Center for Biotechnology and Drug Design, Georgia State University, Atlanta, Georgia 30303-3083, United States
| | - W. David Wilson
- Department
of Chemistry and Center for Biotechnology and Drug Design, Georgia State University, Atlanta, Georgia 30303-3083, United States
| | - Saadia A. Karim
- Cancer
Research UK Beatson Institute, Glasgow G61 1BD, United
Kingdom
| | - Jennifer P. Morton
- Cancer
Research UK Beatson Institute, Glasgow G61 1BD, United
Kingdom
- Institute
of Cancer Sciences, University of Glasgow, Glasgow G61 1QH, United Kingdom
| | - Stephen Neidle
- School
of Pharmacy, University College London, London WC1N 1AX, United Kingdom
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35
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Ferenc G, Váradi Z, Kupihár Z, Paragi G, Kovács L. Analytical and Structural Studies for the Investigation of Oxidative Stress in Guanine Oligonucleotides. Int J Mol Sci 2020; 21:E4981. [PMID: 32679695 PMCID: PMC7404036 DOI: 10.3390/ijms21144981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/08/2020] [Accepted: 07/13/2020] [Indexed: 11/16/2022] Open
Abstract
DNA damage plays a decisive role in epigenetic effects. The detection and analysis of DNA damages, like the most common change of guanine (G) to 8-oxo-7,8-dihydroguanine (OG), is a key factor in cancer research. It is especially true for G quadruplex structure (GQ), which is one of the best-known examples of a non-canonical DNA arrangement. In the present work, we provided an overview on analytical methods in connection with the detection of OG in oligonucleotides with GQ-forming capacity. Focusing on the last five years, novel electrochemical tools, like dedicated electrodes, were overviewed, as well as different optical methods (fluorometric assays, resonance light scattering or UV radiation) along with hyphenated detection and structural analysis methods (CD, NMR, melting temperature analysis and nanopore detection) were also applied for OG detection. Additionally, GQ-related computational simulations were also summarized. All these results emphasize that OG detection and the analysis of the effect of its presence in higher ordered structures like GQ is still a state-of-the-art research line with continuously increasing interest.
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Affiliation(s)
- Györgyi Ferenc
- Nucleic Acid Synthesis Laboratory, Biological Research Centre, Temesvári krt. 62, H-6726 Szeged, Hungary;
| | - Zoltán Váradi
- Nucleic Acids Laboratory, Department of Medicinal Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary; (Z.V.); (Z.K.)
| | - Zoltán Kupihár
- Nucleic Acids Laboratory, Department of Medicinal Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary; (Z.V.); (Z.K.)
| | - Gábor Paragi
- MTA-SZTE Biomimetic Systems Research Group, Dóm tér 8, 6720 Szeged, Hungary
- Institute of Physics, University of Pécs, Ifjúság útja 6, 7624 Pécs, Hungary
| | - Lajos Kovács
- Nucleic Acids Laboratory, Department of Medicinal Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary; (Z.V.); (Z.K.)
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36
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Monsen RC, DeLeeuw L, Dean WL, Gray RD, Sabo T, Chakravarthy S, Chaires JB, Trent JO. The hTERT core promoter forms three parallel G-quadruplexes. Nucleic Acids Res 2020; 48:5720-5734. [PMID: 32083666 PMCID: PMC7261196 DOI: 10.1093/nar/gkaa107] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Revised: 02/06/2020] [Accepted: 02/17/2020] [Indexed: 12/13/2022] Open
Abstract
The structure of the 68 nt sequence with G-quadruplex forming potential within the hTERT promoter is disputed. One model features a structure with three stacked parallel G-quadruplex units, while another features an unusual duplex hairpin structure adjoined to two stacked parallel and antiparallel quadruplexes. We report here the results of an integrated structural biology study designed to distinguish between these possibilities. As part of our study, we designed a sequence with an optimized hairpin structure and show that its biophysical and biochemical properties are inconsistent with the structure formed by the hTERT wild-type sequence. By using circular dichroism, thermal denaturation, nuclear magnetic resonance spectroscopy, analytical ultracentrifugation, small-angle X-ray scattering, molecular dynamics simulations and a DNase I cleavage assay we found that the wild type hTERT core promoter folds into a stacked, three-parallel G-quadruplex structure. The hairpin structure is inconsistent with all of our experimental data obtained with the wild-type sequence. All-atom models for both structures were constructed using molecular dynamics simulations. These models accurately predicted the experimental hydrodynamic properties measured for each structure. We found with certainty that the wild-type hTERT promoter sequence does not form a hairpin structure in solution, but rather folds into a compact stacked three-G-quadruplex conformation.
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Affiliation(s)
- Robert C Monsen
- Department of Biochemistry & Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
| | - Lynn DeLeeuw
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - William L Dean
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - Robert D Gray
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
| | - T Michael Sabo
- Department of Biochemistry & Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Srinivas Chakravarthy
- The Biophysics Collaborative Access Team (BioCAT), Department of Biological Chemical and Physical Sciences, Illinois Institute of Technology, Chicago, IL 60616, USA
| | - Jonathan B Chaires
- Department of Biochemistry & Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - John O Trent
- Department of Biochemistry & Molecular Genetics, University of Louisville, Louisville, KY 40202, USA
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, USA
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
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37
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Vo T, Oxenford S, Angell R, Marchetti C, Ohnmacht SA, Wilson WD, Neidle S. Substituted Naphthalenediimide Compounds Bind Selectively to Two Human Quadruplex Structures with Parallel Topology. ACS Med Chem Lett 2020; 11:991-999. [PMID: 32435416 PMCID: PMC7236248 DOI: 10.1021/acsmedchemlett.0c00041] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/30/2020] [Indexed: 11/28/2022] Open
Abstract
Interactions are reported of three representative naphthalenediimide derivatives with three quadruplex targets, from the promoter region of the telomerase (hTERT) gene, a human telomeric DNA quadruplex, and a telomeric RNA quadruplex (TERRA). Thermal melting studies showed that these compounds strongly stabilize the quadruplexes, with weak stabilization of a duplex DNA. Binding studies by surface plasmon resonance and fluorescence spectroscopy found that the compounds bind to the quadruplexes with nanomolar equilibrium dissociation constants. Plausible topologies for the quadruplex complexes were deduced from CD spectra, which together with the surface plasmon resonance data indicate that the quadruplexes with parallel quadruplex folds are preferred by two compounds, which was confirmed by qualitative molecular modeling.
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Affiliation(s)
- Tam Vo
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States
| | - Sally Oxenford
- UCL
School of Pharmacy, University College London, London WC1N 1AX, U.K.
| | - Richard Angell
- UCL
School of Pharmacy, University College London, London WC1N 1AX, U.K.
| | - Chiara Marchetti
- UCL
School of Pharmacy, University College London, London WC1N 1AX, U.K.
| | | | - W. David Wilson
- Department
of Chemistry, Georgia State University, Atlanta, Georgia 30303, United States
- Center
for Diagnostics and Therapeutics, Georgia
State University, Atlanta, Georgia 30303, United States
| | - Stephen Neidle
- UCL
School of Pharmacy, University College London, London WC1N 1AX, U.K.
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38
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Effects of Length and Loop Composition on Structural Diversity and Similarity of (G 3TG 3N mG 3TG 3) G-Quadruplexes. Molecules 2020; 25:molecules25081779. [PMID: 32294984 PMCID: PMC7221631 DOI: 10.3390/molecules25081779] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/09/2020] [Accepted: 04/09/2020] [Indexed: 11/17/2022] Open
Abstract
A G-rich sequence containing three loops to connect four G-tracts with each ≥2 guanines can possibly form G-quadruplex structures. Given that all G-quadruplex structures comprise the stacking of G-quartets, the loop sequence plays a major role on their folding topology and thermal stability. Here circular dichroism, NMR, and PAGE are used to study the effect of loop length and base composition in the middle loop, and a single base difference in loop 1 and 3 on G-quadruplex formation of (G3HG3NmG3HG3) sequences with and without flanking nucleotides, where H is T, A, or C and N is T, A, C, or G. In addition, melting curve for G-quadruplex unfolding was used to provide relatively thermal stability of G-quadruplex structure after the addition of K+ overnight. We further studied the effects of K+ concentration on their stability and found structural changes in several sequences. Such (G3HG3NmG3HG3) configuration can be found in a number of native DNA sequences. The study of structural diversity and similarity from these sequences may allow us to establish the correlation between model sequences and native sequences. Moreover, several sequences upon interaction with a G-quadruplex ligand, BMVC, show similar spectral change, implying that structural similarity is crucial for drug development.
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39
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Wang ZF, Li MH, Chu IT, Winnerdy FR, Phan AT, Chang TC. Cytosine epigenetic modification modulates the formation of an unprecedented G4 structure in the WNT1 promoter. Nucleic Acids Res 2020; 48:1120-1130. [PMID: 31912153 PMCID: PMC7026657 DOI: 10.1093/nar/gkz1207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Revised: 12/09/2019] [Accepted: 12/18/2019] [Indexed: 12/16/2022] Open
Abstract
Time-resolved imino proton nuclear magnetic resonance spectra of the WT22m sequence d(GGGCCACCGGGCAGTGGGCGGG), derived from the WNT1 promoter region, revealed an intermediate G-quadruplex G4(I) structure during K+-induced conformational transition from an initial hairpin structure to the final G4(II) structure. Moreover, a single-base C-to-T mutation at either position C4 or C7 of WT22m could lock the intermediate G4(I) structure without further conformational change to the final G4(II) structure. Surprisingly, we found that the intermediate G4(I) structure is an atypical G4 structure, which differs from a typical hybrid G4 structure of the final G4(II) structure. Further studies of modified cytosine analogues associated with epigenetic regulation indicated that slight modification on a cytosine could modulate G4 structure. A simplified four-state transition model was introduced to describe such conformational transition and disclose the possible mechanism for G4 structural selection caused by cytosine modification.
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Affiliation(s)
- Zi-Fu Wang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan, R.O.C
| | - Ming-Hao Li
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan, R.O.C
| | - I-Te Chu
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan, R.O.C.,Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, R.O.C
| | - Fernaldo R Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Anh T Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
| | - Ta-Chau Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan, R.O.C.,Department of Chemistry, National Taiwan University, Taipei 106, Taiwan, R.O.C
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40
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Ma Y, Iida K, Nagasawa K. Topologies of G-quadruplex: Biological functions and regulation by ligands. Biochem Biophys Res Commun 2020; 531:3-17. [PMID: 31948752 DOI: 10.1016/j.bbrc.2019.12.103] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 12/20/2019] [Accepted: 12/28/2019] [Indexed: 01/06/2023]
Abstract
G-Quadruplex (G4) is one of the higher-order structures occurring in guanine-rich sequences of nucleic acids, and plays critical roles in biological processes. The G4-forming sequences can generate three kinds of topologies, i.e., parallel, anti-parallel, and hybrid, and these polymorphic structures have an important influence on G4-related biological functions. In this review, we highlight variety of structures generated by G4s containing various sequences and under diverse conditions. We also discuss the G4 ligands which induce specific topologies and/or conversion between different topologies.
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Affiliation(s)
- Yue Ma
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Japan.
| | - Keisuke Iida
- Department of Chemistry, Chiba University, Japan
| | - Kazuo Nagasawa
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Japan.
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41
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Grün JT, Hennecker C, Klötzner DP, Harkness RW, Bessi I, Heckel A, Mittermaier AK, Schwalbe H. Conformational Dynamics of Strand Register Shifts in DNA G-Quadruplexes. J Am Chem Soc 2019; 142:264-273. [PMID: 31815451 DOI: 10.1021/jacs.9b10367] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The complex folding energy landscape of DNA G-quadruplexes leads to numerous conformations for this functionally important class of noncanonical DNA structures. A new layer of conformational heterogeneity comes from sequences with different numbers of G-nucleotides in each of the DNA G-strands that form the four-stranded G-quartet core. The mechanisms by which G-quadruplexes transition from one folded conformation to another are currently unknown. To address this question, we studied two different G-quadruplexes, selecting a single conformation by blocking hydrogen bonding with photolabile protection groups. Upon irradiation, the block can be released and the kinetics of re-equilibration to the native conformational equilibrium can be determined by time-resolved NMR. We compared the NMR-derived refolding kinetics with data derived from thermal hysteresis folding kinetic experiments and found excellent agreement. The outlined methodological approach allows separation of K+-induced G-quadruplex formation and subsequent refolding and provides key insight into rate-limiting steps of G-quadruplex conformational dynamics.
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Affiliation(s)
- J Tassilo Grün
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany.,Center of Biomolecular Magnetic Resonance (BMRZ) , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | | | - Dean-Paulos Klötzner
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | - Robert W Harkness
- Department of Chemistry , McGill University , Montreal H3A 2K6 , Quebec , Canada
| | - Irene Bessi
- Institute of Organic Chemistry , Julius-Maximilians-University Würzburg , Würzburg 97074 , Germany
| | - Alexander Heckel
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
| | | | - Harald Schwalbe
- Institute for Organic Chemistry and Chemical Biology , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany.,Center of Biomolecular Magnetic Resonance (BMRZ) , Goethe University Frankfurt am Main , Frankfurt 60438 , Germany
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42
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Platella C, Raucci U, Rega N, D'Atri S, Levati L, Roviello GN, Fuggetta MP, Musumeci D, Montesarchio D. Shedding light on the interaction of polydatin and resveratrol with G-quadruplex and duplex DNA: a biophysical, computational and biological approach. Int J Biol Macromol 2019; 151:1163-1172. [PMID: 31747572 DOI: 10.1016/j.ijbiomac.2019.10.160] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/09/2019] [Accepted: 10/18/2019] [Indexed: 12/17/2022]
Abstract
Among polyphenols, trans-resveratrol (tRES) and trans-polydatin (tPD) exert multiple biological effects, particularly antioxidant and antiproliferative. In this work, we have investigated the interaction of tPD with three cancer-related DNA sequences able to form G-quadruplex (G4) structures, as well as with a model duplex, and compared its behaviour with tRES. Interestingly, fluorescence analysis evidenced the ability of tPD to bind all the studied DNA systems, similarly to tRES, with tRES displaying a higher ability to discriminate G4 over duplex with respect to tPD. However, neither tRES nor tPD produced significant conformational changes of the analyzed DNA upon binding, as determined by CD-titration analysis. Computational analysis and biological data confirmed the biophysical results: indeed, molecular docking evidenced the stronger interaction of tRES with the promoter of c-myc oncogene, and immunoblotting assays revealed a reduction of c-myc expression, more effective for tRES than tPD. Furthermore, in vitro assays on melanoma cells proved that tPD was able to significantly reduce telomerase activity, and inhibit cell proliferation, with tRES producing higher effects than tPD.
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Affiliation(s)
- Chiara Platella
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, Naples I-80126, Italy
| | - Umberto Raucci
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, Naples I-80126, Italy
| | - Nadia Rega
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, Naples I-80126, Italy; Interdisciplinary Research Centre on Biomaterials (CRIB), University of Naples Federico II, Piazzale Tecchio 80, Naples I-80125, Italy
| | - Stefania D'Atri
- Laboratory of Molecular Oncology, IDI-IRCCS, Via dei Monti di Creta 104, Rome I-00167, Italy
| | - Lauretta Levati
- Laboratory of Molecular Oncology, IDI-IRCCS, Via dei Monti di Creta 104, Rome I-00167, Italy
| | - Giovanni N Roviello
- Institute of Biostructures and Bioimages, CNR, Via Mezzocannone 16, Naples I-80134, Italy
| | - Maria Pia Fuggetta
- Institute of Translational Pharmacology, CNR, Via Fosso del Cavaliere 100, Rome I-00133, Italy.
| | - Domenica Musumeci
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, Naples I-80126, Italy; Institute of Biostructures and Bioimages, CNR, Via Mezzocannone 16, Naples I-80134, Italy.
| | - Daniela Montesarchio
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 21, Naples I-80126, Italy
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43
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Dhamodharan V, Pradeepkumar PI. Specific Recognition of Promoter G-Quadruplex DNAs by Small Molecule Ligands and Light-up Probes. ACS Chem Biol 2019; 14:2102-2114. [PMID: 31532996 DOI: 10.1021/acschembio.9b00475] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
G-Quadruplexes (G4s) are four-stranded nucleic acid structures whose underlying G-rich sequences are present across the chromosome and transcriptome. These highly structured elements are known to regulate many key biological functions such as replication, transcription, translation, and genomic stability, thereby providing an additional layer of gene regulation. G4s are structurally dynamic and diverse, and they can fold into numerous topologies. They are potential targets for small molecules, which can modulate their functions. To this end, myriad classes of small molecules have been developed and studied for their ability to bind and stabilize these unique structures. Though many of them can selectively target G4s over duplex DNA, only a few of them can distinguish one G4 topology from others. Design and development of G4-specific ligands are challenging owing to the subtle structural variations among G4 structures. However, screening assays and computational methods have identified a few classes of ligands that preferentially or specifically target the G4 topology of interest over others. This review focuses on the small molecules and fluorescent probes that specifically target human promoter G4s associated with oncogenes. Targeting promoter G4s could circumvent the issues such as undruggability and development of drug resistance associated with the protein targets. The ligands discussed here highlight that development of G4-specific ligands is an achievable goal in spite of the limited structural data available. The future goal is to pursue the development of G4-specific ligands endowed with drug-like properties for G4-based therapeutics and diagnostics.
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Affiliation(s)
- V. Dhamodharan
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
- Okinawa Institute of Science and Technology Graduate University, Okinawa 9040495, Japan
| | - P. I. Pradeepkumar
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
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44
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Wan C, Fu W, Jing H, Zhang N. NMR solution structure of an asymmetric intermolecular leaped V-shape G-quadruplex: selective recognition of the d(G2NG3NG4) sequence motif by a short linear G-rich DNA probe. Nucleic Acids Res 2019; 47:1544-1556. [PMID: 30445650 PMCID: PMC6379650 DOI: 10.1093/nar/gky1167] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 11/01/2018] [Accepted: 11/04/2018] [Indexed: 02/07/2023] Open
Abstract
Aside from classical loops among G-quadruplexes, the unique leaped V-shape scaffold spans over three G-tetrads, without any intervening residues. This scaffold enables a sharp reversal of two adjacent strand directions and simultaneously participates in forming the G-tetrad core. These features make this scaffold itself distinctive and thus an essentially more accessible target. As an alternative to the conventional antisense method using a complementary chain, forming an intermolecular G-quadruplex from two different oligomers, in which the longer one as the target is captured by a short G-rich fragment, could be helpful for recognizing G-rich sequences and structural motifs. However, such an intermolecular leaped V-shape G-quadruplex consisting of DNA oligomers of quite different lengths has not been evaluated. Here, we present the first nuclear magnetic resonance (NMR) study of an asymmetric intermolecular leaped V-shape G-quadruplex assembled between an Oxytricha nova telomeric sequence d(G2T4G4T4G4) and a single G-tract fragment d(TG4A). Furthermore, we explored the selectivity of this short fragment as a potential probe, examined the kinetic discrimination for probing a specific mutant, and proposed the key sequence motif d(G2NG3NG4) essential for building the leaped V-shape G-quadruplexes.
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Affiliation(s)
- Chanjuan Wan
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Wenqiang Fu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Haitao Jing
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Na Zhang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.,Key Laboratory of Anhui Province for High Field Magnetic Resonance Imaging, Hefei 230031, China
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45
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Dickerhoff J, Onel B, Chen L, Chen Y, Yang D. Solution Structure of a MYC Promoter G-Quadruplex with 1:6:1 Loop Length. ACS OMEGA 2019; 4:2533-2539. [PMID: 30842981 PMCID: PMC6396123 DOI: 10.1021/acsomega.8b03580] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 01/17/2019] [Indexed: 06/09/2023]
Abstract
The important MYC oncogene is deregulated in many cancer cells and comprises one of the most prominent G-quadruplex (G4) forming sequences in its promoter regions, the NHE III1 motif. Formation of G4s suppresses MYC transcription and can be modulated by drug binding, establishing these DNA structures as promising targets in cancer therapy. The NHE III1 motif can fold into more than one parallel G4s, including 1:2:1 and 1:6:1 loop length conformers, with the 1:2:1 conformer shown as the major species under physiological conditions in solution. However, additional factors such as protein interactions may affect the cellular folding equilibrium. Nucleolin, a protein shown to bind MYC G4 and repress MYC transcription, is reported herein to preferably bind to the 1:6:1 loop length conformer suggesting a physiological significance of this species. The high-resolution NMR solution structure of the 1:6:1 conformer is determined, which reveals a 5'-capping structure distinctive from the 1:2:1 form, with the 6 nt central loop playing an essential role for this specific capping structure. This suggests that each parallel G-quadruplex likely adopts unique capping and loop structures determined by the specific central loop and flanking sequences. The resulting structural information at the molecular level will help to understand protein recognition of different G4s, contribution of G4 polymorphism to gene regulation, and to rationally design small molecules selectively targeting the 1:6:1 MYC G4.
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Affiliation(s)
- Jonathan Dickerhoff
- College
of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 W Stadium Avenue, West
Lafayette, Indiana 47907, United States
| | - Buket Onel
- College
of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 W Stadium Avenue, West
Lafayette, Indiana 47907, United States
| | - Luying Chen
- College
of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 W Stadium Avenue, West
Lafayette, Indiana 47907, United States
| | - Yuwei Chen
- Department
of Chemistry and Biochemistry, College of Science, University of Arizona, 1306 E. University Blvd, Tucson, Arizona 85721, United
States
| | - Danzhou Yang
- College
of Pharmacy, Medicinal Chemistry and Molecular Pharmacology, Purdue University, 575 W Stadium Avenue, West
Lafayette, Indiana 47907, United States
- Center
for Cancer Research, Purdue University, 201 S University Street, West Lafayette, Indiana 47906, United States
- Purdue
Institute for Drug Discovery, 720 Clinic Dr, West Lafayette, Indiana 47907, United
States
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46
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Sengar A, Vandana J, Chambers VS, Di Antonio M, Winnerdy F, Balasubramanian S, Phan AT. Structure of a (3+1) hybrid G-quadruplex in the PARP1 promoter. Nucleic Acids Res 2019; 47:1564-1572. [PMID: 30551210 PMCID: PMC6379715 DOI: 10.1093/nar/gky1179] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 11/02/2018] [Accepted: 12/12/2018] [Indexed: 01/08/2023] Open
Abstract
Poly (ADP-ribose) polymerase 1 (PARP1) has emerged as an attractive target for cancer therapy due to its key role in DNA repair processes. Inhibition of PARP1 in BRCA-mutated cancers has been observed to be clinically beneficial. Recent genome-mapping experiments have identified a non-canonical G-quadruplex-forming sequence containing bulges within the PARP1 promoter. Structural features, like bulges, provide opportunities for selective chemical targeting of the non-canonical G-quadruplex structure within the PARP1 promoter, which could serve as an alternative therapeutic approach for the regulation of PARP1 expression. Here we report the G-quadruplex structure formed by a 23-nucleotide G-rich sequence in the PARP1 promoter. Our study revealed a three-layered intramolecular (3+1) hybrid G-quadruplex scaffold, in which three strands are oriented in one direction and the fourth in the opposite direction. This structure exhibits unique structural features such as an adenine bulge and a G·G·T base triple capping structure formed between the central edgewise loop, propeller loop and 5' flanking terminal. Given the highly important role of PARP1 in DNA repair and cancer intervention, this structure presents an attractive opportunity to explore the therapeutic potential of PARP1 inhibition via G-quadruplex DNA targeting.
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Affiliation(s)
- Anjali Sengar
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - J Jeya Vandana
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Vicki S Chambers
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Marco Di Antonio
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Shankar Balasubramanian
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK
- Cancer Research UK Cambridge Institute, University of Cambridge, Li Ka Shing Centre, Cambridge CB2 0RE, UK
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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47
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Abstract
G-quadruplexes (G4s) have become one of the most exciting nucleic acid secondary structures. A noncanonical, four-stranded structure formed in guanine-rich DNA and RNA sequences, G-quadruplexes can readily form under physiologically relevant conditions and are globularly folded structures. DNA is widely recognized as a double-helical structure essential in genetic information storage. However, only ~3% of the human genome is expressed in protein; RNA and DNA may form noncanonical secondary structures that are functionally important. G-quadruplexes are one such example which have gained considerable attention for their formation and regulatory roles in biologically significant regions, such as human telomeres, oncogene-promoter regions, replication initiation sites, and 5'- and 3'-untranslated region (UTR) of mRNA. They are shown to be a regulatory motif in a number of critical cellular processes including gene transcription, translation, replication, and genomic stability. G-quadruplexes are also found in nonhuman genomes, particularly those of human pathogens. Therefore, G-quadruplexes have emerged as a new class of molecular targets for drug development. In addition, there is considerable interest in the use of G-quadruplexes for biomaterials, biosensors, and biocatalysts. The First International Meeting on Quadruplex DNA was held in 2007, and the G-quadruplex field has been growing dramatically over the last decade. The methods used to study G-quadruplexes have been essential to the rapid progress in our understanding of this exciting nucleic acid secondary structure.
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Affiliation(s)
- Danzhou Yang
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, Purdue Center for Cancer Research, Purdue Institute for Drug Discovery, West Lafayette, IN USA
| | - Clement Lin
- Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, West Lafayette, IN USA
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48
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Abstract
BACKGROUND Numerous different types of variations can occur in DNA and have diverse effects and consequences. The Variation Ontology (VariO) was developed for systematic descriptions of variations and their effects at DNA, RNA and protein levels. RESULTS VariO use and terms for DNA variations are described in depth. VariO provides systematic names for variation types and detailed descriptions for changes in DNA function, structure and properties. The principles of VariO are presented along with examples from published articles or databases, most often in relation to human diseases. VariO terms describe local DNA changes, chromosome number and structure variants, chromatin alterations, as well as genomic changes, whether of genetic or non-genetic origin. CONCLUSIONS DNA variation systematics facilitates unambiguous descriptions of variations and their effects and further reuse and integration of data from different sources by both human and computers.
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Affiliation(s)
- Mauno Vihinen
- Department of Experimental Medical Science, Lund University, BMC B13, SE-22184, Lund, Sweden.
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49
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Qin QP, Zou BQ, Hu FL, Huang GB, Wang SL, Gu YQ, Tan MX. Platinum(ii) complexes with rutaecarpine and tryptanthrin derivatives induce apoptosis by inhibiting telomerase activity and disrupting mitochondrial function. MEDCHEMCOMM 2018; 9:1639-1648. [PMID: 30429969 PMCID: PMC6195000 DOI: 10.1039/c8md00247a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/07/2018] [Indexed: 12/17/2022]
Abstract
Four new platinum(ii) complexes, [Pt(Rut)(DMSO)Cl2] (Rut-Pt), [Pt(Try)(DMSO)Cl2] (Try-Pt), [Pt(ITry)(DMSO)Cl2] (ITry-Pt) and [Pt(BrTry)(DMSO)Cl2] (BrTry-Pt), with rutaecarpine (Rut), tryptanthrin (Try), 8-iodine-tryptanthrin (ITry) and 8-bromo-tryptanthrin (BrTry) as ligands were synthesized and fully characterized. In these complexes, the platinum(ii) adopts a four-coordinated square planar geometry. The inhibitory activity evaluated by the MTT assay showed that BrTry-Pt (IC50 = of 0.21 ± 0.25 μM) could inhibit the growth of T-24 tumor cells (human bladder cancer cell line) more so than the other three complexes. In addition, all of these Pt complexes exhibited low toxicity against non-cancerous HL-7702 cells. BrTry-Pt induced cell cycle arrest in the S phase, leading to the down-regulation of cyclin A and CDK2 proteins. BrTry-Pt acts as a telomerase inhibitor targeting the c-myc promoter. In addition, BrTry-Pt also caused mitochondrial dysfunction. Importantly, the in vitro anticancer activity of BrTry-Pt was higher than those of Rut-Pt, Try-Pt and ITry-Pt, and it was more selective for T-24 cells than for non-cancerous HL-7702 cells.
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Affiliation(s)
- Qi-Pin Qin
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources , School of Chemistry and Pharmacy , Guangxi Normal University , 15 Yucai Road , Guilin 541004 , PR China
| | - Bi-Qun Zou
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
- Department of Chemistry , Guilin Normal College , 21 Xinyi Road , Gulin 541001 , PR China
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources , School of Chemistry and Pharmacy , Guangxi Normal University , 15 Yucai Road , Guilin 541004 , PR China
| | - Fei-Long Hu
- Guangxi Key Laboratory of Chemistry and Engineering of Forest Products , Guangxi University for Nationalities , Nanning , 530006 , P. R. China
| | - Guo-Bao Huang
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
| | - Shu-Long Wang
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources , School of Chemistry and Pharmacy , Guangxi Normal University , 15 Yucai Road , Guilin 541004 , PR China
| | - Yun-Qiong Gu
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
- State Key Laboratory for the Chemistry and Molecular Engineering of Medicinal Resources , School of Chemistry and Pharmacy , Guangxi Normal University , 15 Yucai Road , Guilin 541004 , PR China
| | - Ming-Xiong Tan
- Guangxi Key Lab of Agricultural Resources Chemistry and Biotechnology , School of Chemistry and Food Science , Yulin Normal University , 1303 Jiaoyudong Road , Yulin 537000 , PR China . ; ; Tel: +86 775 2623650
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50
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Mancini A, Xavier-Magalhães A, Woods WS, Nguyen KT, Amen AM, Hayes JL, Fellmann C, Gapinske M, McKinney AM, Hong C, Jones LE, Walsh KM, Bell RJA, Doudna JA, Costa BM, Song JS, Perez-Pinera P, Costello JF. Disruption of the β1L Isoform of GABP Reverses Glioblastoma Replicative Immortality in a TERT Promoter Mutation-Dependent Manner. Cancer Cell 2018; 34:513-528.e8. [PMID: 30205050 PMCID: PMC6135086 DOI: 10.1016/j.ccell.2018.08.003] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 07/02/2018] [Accepted: 08/03/2018] [Indexed: 12/27/2022]
Abstract
TERT promoter mutations reactivate telomerase, allowing for indefinite telomere maintenance and enabling cellular immortalization. These mutations specifically recruit the multimeric ETS factor GABP, which can form two functionally independent transcription factor species: a dimer or a tetramer. We show that genetic disruption of GABPβ1L (β1L), a tetramer-forming isoform of GABP that is dispensable for normal development, results in TERT silencing in a TERT promoter mutation-dependent manner. Reducing TERT expression by disrupting β1L culminates in telomere loss and cell death exclusively in TERT promoter mutant cells. Orthotopic xenografting of β1L-reduced, TERT promoter mutant glioblastoma cells rendered lower tumor burden and longer overall survival in mice. These results highlight the critical role of GABPβ1L in enabling immortality in TERT promoter mutant glioblastoma.
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Affiliation(s)
- Andrew Mancini
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Ana Xavier-Magalhães
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA; Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, 4710-057 Braga, Portugal
| | - Wendy S Woods
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Kien-Thiet Nguyen
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Alexandra M Amen
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA; Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Josie L Hayes
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Christof Fellmann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Michael Gapinske
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Andrew M McKinney
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Chibo Hong
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Lindsey E Jones
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Kyle M Walsh
- Division of Neuroepidemiology, Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Robert J A Bell
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA
| | - Jennifer A Doudna
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA; Department of Chemistry, University of California, Berkeley, CA 94720, USA; Innovative Genomics Institute, University of California, Berkeley, CA 94720, USA; MBIB Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Howard Hughes Medical Institute (HHMI), Berkeley, CA 94720, USA
| | - Bruno M Costa
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, 4710-057 Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga/Guimarães, 4710-057 Braga, Portugal
| | - Jun S Song
- Department of Physics, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Pablo Perez-Pinera
- Department of Bioengineering, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA; Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA
| | - Joseph F Costello
- Department of Neurological Surgery, University of California, San Francisco, CA 94158, USA.
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