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Geng Y, Liu C, Xu N, Suen MC, Miao H, Xie Y, Zhang B, Chen X, Song Y, Wang Z, Cai Q, Zhu G. Crystal structure of a tetrameric RNA G-quadruplex formed by hexanucleotide repeat expansions of C9orf72 in ALS/FTD. Nucleic Acids Res 2024; 52:7961-7970. [PMID: 38860430 PMCID: PMC11260476 DOI: 10.1093/nar/gkae473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 05/16/2024] [Accepted: 05/29/2024] [Indexed: 06/12/2024] Open
Abstract
The abnormal GGGGCC hexanucleotide repeat expansions (HREs) in C9orf72 cause the fatal neurodegenerative diseases including amyotrophic lateral sclerosis and frontotemporal dementia. The transcribed RNA HREs, short for r(G4C2)n, can form toxic RNA foci which sequestrate RNA binding proteins and impair RNA processing, ultimately leading to neurodegeneration. Here, we determined the crystal structure of r(G4C2)2, which folds into a parallel tetrameric G-quadruplex composed of two four-layer dimeric G-quadruplex via 5'-to-5' stacking in coordination with a K+ ion. Notably, the two C bases locate at 3'- end stack on the outer G-tetrad with the assistance of two additional K+ ions. The high-resolution structure reported here lays a foundation in understanding the mechanism of neurological toxicity of RNA HREs. Furthermore, the atomic details provide a structural basis for the development of potential therapeutic agents against the fatal neurodegenerative diseases ALS/FTD.
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Affiliation(s)
- Yanyan Geng
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Changdong Liu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Naining Xu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Monica Ching Suen
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
| | - Haitao Miao
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Yuanyuan Xie
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Bingchang Zhang
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Xueqin Chen
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yuanjian Song
- Jiangsu Key Laboratory of Brain Disease Bioinformation, Department of Genetics, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Zhanxiang Wang
- Department of Neurosurgery and Department of Neuroscience, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Qixu Cai
- State Key Laboratory of Vaccines for Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian, China
| | - Guang Zhu
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
- HKUST Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen, Guangdong, China
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2
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Yang Y, Wang Y, Yan Z, Li Z, Guo P. Effects of interrupting residues on DNA dumbbell structures formed by CCTG tetranucleotide repeats associated with myotonic dystrophy type 2. FEBS Lett 2024. [PMID: 38922834 DOI: 10.1002/1873-3468.14952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/03/2024] [Accepted: 05/15/2024] [Indexed: 06/28/2024]
Abstract
Myotonic dystrophy type 2 (DM2) is a neurogenerative disease caused by caprylic/capric triglyceride (CCTG) tetranucleotide repeat expansions in intron 1 of the cellular nucleic acid-binding protein (CNBP) gene. Non-B DNA structures formed by CCTG repeats can promote genetic instability, whereas interrupting motifs of NCTG (N = A/T/G) within CCTG repeats help to maintain genomic stability. However, whether the interrupting motifs can affect DNA structures of CCTG repeats remains unclear. Here, we report that four CCTG repeats with an interrupting 3'-A/T/G residue formed dumbbell structures, whereas a non-interrupting 3'-C residue resulted in a multi-loop structure exhibiting conformational dynamics that may contribute to a higher tendency of escaping from DNA mismatch repair and causing repeat expansions. The results provide new structural insights into the genetic instability of CCTG repeats in DM2.
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Affiliation(s)
- Yingquan Yang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
- Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM) Chinese Academy of Sciences, China
| | - Yang Wang
- Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM) Chinese Academy of Sciences, China
- School of Materials Science and Engineering, Tianjin University, China
| | - Zhenzhen Yan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
- Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM) Chinese Academy of Sciences, China
| | - Zhigang Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Pei Guo
- Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM) Chinese Academy of Sciences, China
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3
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Trajkovski M, Pastore A, Plavec J. Dimeric structures of DNA ATTTC repeats promoted by divalent cations. Nucleic Acids Res 2024; 52:1591-1601. [PMID: 38296828 PMCID: PMC10899783 DOI: 10.1093/nar/gkae052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 01/10/2024] [Accepted: 01/16/2024] [Indexed: 02/02/2024] Open
Abstract
Structural studies of repetitive DNA sequences may provide insights why and how certain repeat instabilities in their number and nucleotide sequence are managed or even required for normal cell physiology, while genomic variability associated with repeat expansions may also be disease-causing. The pentanucleotide ATTTC repeats occur in hundreds of genes important for various cellular processes, while their insertion and expansion in noncoding regions are associated with neurodegeneration, particularly with subtypes of spinocerebellar ataxia and familial adult myoclonic epilepsy. We describe a new striking domain-swapped DNA-DNA interaction triggered by the addition of divalent cations, including Mg2+ and Ca2+. The results of NMR characterization of d(ATTTC)3 in solution show that the oligonucleotide folds into a novel 3D architecture with two central C:C+ base pairs sandwiched between a couple of T:T base pairs. This structural element, referred to here as the TCCTzip, is characterized by intercalative hydrogen-bonding, while the nucleobase moieties are poorly stacked. The 5'- and 3'-ends of TCCTzip motif are connected by stem-loop segments characterized by A:T base pairs and stacking interactions. Insights embodied in the non-canonical DNA structure are expected to advance our understanding of why only certain pyrimidine-rich DNA repeats appear to be pathogenic, while others can occur in the human genome without any harmful consequences.
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Affiliation(s)
- Marko Trajkovski
- Slovenian NMR Centre, National Institute of Chemistry, 1000 Ljubljana, Slovenia
| | - Annalisa Pastore
- King's College London, the Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, 1000 Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana, Slovenia
- EN-FIST, Center of Excellence, 1000 Ljubljana, Slovenia
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4
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Geng Y, Cai Q. Role of C9orf72 hexanucleotide repeat expansions in ALS/FTD pathogenesis. Front Mol Neurosci 2024; 17:1322720. [PMID: 38318532 PMCID: PMC10838790 DOI: 10.3389/fnmol.2024.1322720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 01/04/2024] [Indexed: 02/07/2024] Open
Abstract
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are progressive neurological disorders that share neurodegenerative pathways and features. The most prevalent genetic causes of ALS/FTD is the GGGGCC hexanucleotide repeat expansions in the first intron region of the chromosome 9 open reading frame 72 (C9orf72) gene. In this review, we comprehensively summarize the accumulating evidences elucidating the pathogenic mechanism associated with hexanucleotide repeat expansions in ALS/FTD. These mechanisms encompass the structural polymorphism of DNA and transcribed RNA, the formation of RNA foci via phase separation, and the cytoplasmic accumulation and toxicities of dipeptide-repeat proteins. Additionally, the formation of G-quadruplex structures significantly impairs the expression and normal function of the C9orf72 protein. We also discuss the sequestration of specific RNA binding proteins by GGGGCC RNA, which further contributes to the toxicity of C9orf72 hexanucleotide repeat expansions. The deeper understanding of the pathogenic mechanism of hexanucleotide repeat expansions in ALS/FTD provides multiple potential drug targets for these devastating diseases.
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Affiliation(s)
- Yanyan Geng
- Clinical Research Institute of the First Affiliated Hospital of Xiamen University, Fujian Key Laboratory of Brain Tumors Diagnosis and Precision Treatment, Xiamen Key Laboratory of Brain Center, the First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Qixu Cai
- State Key Laboratory of Vaccines for Infectious Diseases, School of Public Health, Xiamen University, Xiamen, Fujian, China
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Yoo H, Lee HR, Kang SB, Lee J, Park K, Yoo H, Kim J, Chung TD, Lee KM, Lim HH, Son CY, Sun JY, Oh SS. G-Quadruplex-Filtered Selective Ion-to-Ion Current Amplification for Non-Invasive Ion Monitoring in Real Time. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2303655. [PMID: 37433455 DOI: 10.1002/adma.202303655] [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: 04/19/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 07/13/2023]
Abstract
Living cells efflux intracellular ions for maintaining cellular life, so intravital measurements of specific ion signals are of significant importance for studying cellular functions and pharmacokinetics. In this work, de novo synthesis of artificial K+ -selective membrane and its integration with polyelectrolyte hydrogel-based open-junction ionic diode (OJID) is demonstrated, achieving a real-time K+ -selective ion-to-ion current amplification in complex bioenvironments. By mimicking biological K+ channels and nerve impulse transmitters, in-line K+ -binding G-quartets are introduced across freestanding lipid bilayers by G-specific hexylation of monolithic G-quadruplex, and the pre-filtered K+ flow is directly converted to amplified ionic currents by the OJID with a fast response time at 100 ms intervals. By the synergistic combination of charge repulsion, sieving, and ion recognition, the synthetic membrane allows K+ transport exclusively without water leakage; it is 250× and 17× more permeable toward K+ than monovalent anion, Cl- , and polyatomic cation, N-methyl-d-glucamine+ , respectively. The molecular recognition-mediated ion channeling provides a 500% larger signal for K+ as compared to Li+ (0.6× smaller than K+ ) despite the same valence. Using the miniaturized device, non-invasive, direct, and real-time K+ efflux monitoring from living cell spheroids is achieved with minimal crosstalk, specifically in identifying osmotic shock-induced necrosis and drug-antidote dynamics.
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Affiliation(s)
- Hyebin Yoo
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Hyun-Ro Lee
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Soon-Bo Kang
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Juhwa Lee
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Kunwoong Park
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Hyunjae Yoo
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
| | - Jinmin Kim
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, South Korea
| | - Kyung-Mi Lee
- Department of Biochemistry and Molecular Biology, Korea University College of Medicine, Seoul, 02841, South Korea
| | - Hyun-Ho Lim
- Neurovascular Unit Research Group, Korea Brain Research Institute (KBRI), Daegu, 41062, South Korea
| | - Chang Yun Son
- Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Incheon, 21983, South Korea
| | - Jeong-Yun Sun
- Department of Materials Science & Engineering, Seoul National University, Seoul, 08826, South Korea
- Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul, 08826, South Korea
| | - Seung Soo Oh
- Department of Materials Science & Engineering, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk, 37673, South Korea
- Institute for Convergence Research and Education in Advanced Technology (I-CREATE), Yonsei University, Incheon, 21983, South Korea
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6
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Zalar M, Wang B, Plavec J, Šket P. Insight into Tetramolecular DNA G-Quadruplexes Associated with ALS and FTLD: Cation Interactions and Formation of Higher-Ordered Structure. Int J Mol Sci 2023; 24:13437. [PMID: 37686239 PMCID: PMC10487854 DOI: 10.3390/ijms241713437] [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: 07/18/2023] [Revised: 08/24/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
The G4C2 hexanucleotide repeat expansion in the c9orf72 gene is a major genetic cause of familial amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD), with the formation of G-quadruplexes directly linked to the development of these diseases. Cations play a crucial role in the formation and structure of G-quadruplexes. In this study, we investigated the impact of biologically relevant potassium ions on G-quadruplex structures and utilized 15N-labeled ammonium cations as a substitute for K+ ions to gain further insights into cation binding and exchange dynamics. Through nuclear magnetic resonance spectroscopy and molecular dynamics simulations, we demonstrate that the single d(G4C2) repeat, in the presence of 15NH4+ ions, adopts a tetramolecular G-quadruplex with an all-syn quartet at the 5'-end. The movement of 15NH4+ ions through the central channel of the G-quadruplex, as well as to the bulk solution, is governed by the vacant cation binding site, in addition to the all-syn quartet at the 5'-end. Furthermore, the addition of K+ ions to G-quadruplexes folded in the presence of 15NH4+ ions induces stacking of G-quadruplexes via their 5'-end G-quartets, leading to the formation of stable higher-ordered species.
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Affiliation(s)
- Matja Zalar
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
| | - Baifan Wang
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
- EN-FIST Center of Excellence, Trg OF 13, SI-1000 Ljubljana, Slovenia
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI-1000 Ljubljana, Slovenia
| | - Primož Šket
- Slovenian NMR Center, National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia; (M.Z.); (B.W.); (J.P.)
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7
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Liu X, Zhao X, He J, Wang S, Shen X, Liu Q, Wang S. Advances in the Structure of GGGGCC Repeat RNA Sequence and Its Interaction with Small Molecules and Protein Partners. Molecules 2023; 28:5801. [PMID: 37570771 PMCID: PMC10420822 DOI: 10.3390/molecules28155801] [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: 06/26/2023] [Revised: 07/21/2023] [Accepted: 07/21/2023] [Indexed: 08/13/2023] Open
Abstract
The aberrant expansion of GGGGCC hexanucleotide repeats within the first intron of the C9orf72 gene represent the predominant genetic etiology underlying amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). The transcribed r(GGGGCC)n RNA repeats form RNA foci, which recruit RNA binding proteins and impede their normal cellular functions, ultimately resulting in fatal neurodegenerative disorders. Furthermore, the non-canonical translation of the r(GGGGCC)n sequence can generate dipeptide repeats, which have been postulated as pathological causes. Comprehensive structural analyses of r(GGGGCC)n have unveiled its polymorphic nature, exhibiting the propensity to adopt dimeric, hairpin, or G-quadruplex conformations, all of which possess the capacity to interact with RNA binding proteins. Small molecules capable of binding to r(GGGGCC)n have been discovered and proposed as potential lead compounds for the treatment of ALS and FTD. Some of these molecules function in preventing RNA-protein interactions or impeding the phase transition of r(GGGGCC)n. In this review, we present a comprehensive summary of the recent advancements in the structural characterization of r(GGGGCC)n, its propensity to form RNA foci, and its interactions with small molecules and proteins. Specifically, we emphasize the structural diversity of r(GGGGCC)n and its influence on partner binding. Given the crucial role of r(GGGGCC)n in the pathogenesis of ALS and FTD, the primary objective of this review is to facilitate the development of therapeutic interventions targeting r(GGGGCC)n RNA.
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Affiliation(s)
- Xiaole Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Xinyue Zhao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Jinhan He
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Sishi Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Xinfei Shen
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Qingfeng Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
| | - Shenlin Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China; (X.L.); (X.Z.); (J.H.); (S.W.); (X.S.); (Q.L.)
- Beijing NMR Center, Peking University, Beijing 100087, China
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Zhang Y, Huang J, Yu K, Cui X. G-Quadruplexes Formation by the C9orf72 Nucleotide Repeat Expansion d(GGGGCC) n and Conformation Regulation by Fangchinoline. Molecules 2023; 28:4671. [PMID: 37375224 DOI: 10.3390/molecules28124671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 06/01/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
The G-quadruplex (GQ)-forming hexanucleotide repeat expansion (HRE) in the C9orf72 (C9) gene has been found to be the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (collectively, C9ALS/FTD), implying the great significance of modulating C9-HRE GQ structures in C9ALS/FTD therapeutic treatment strategies. In this study, we investigated the GQ structures formed by varied lengths of C9-HRE DNA sequences d(GGGGCC)4 (C9-24mer) and d(GGGGCC)8 (C9-48mer), and found that the C9-24mer forms anti-parallel GQ (AP-GQ) in the presence of potassium ions, while the long C9-48mer bearing eight guanine tracts forms unstacked tandem GQ consisting of two C9-24mer unimolecular AP-GQs. Moreover, the natural small molecule Fangchinoline was screened out in order to be able to stabilize and alter the C9-HRE DNA to parallel GQ topology. Further study of the interaction of Fangchinoline with the C9-HRE RNA GQ unit r(GGGGCC)4 (C9-RNA) revealed that it can also recognize and improve the thermal stability of C9-HRE RNA GQ. Finally, use of AutoDock simulation results indicated that Fangchinoline binds to the groove regions of the parallel C9-HRE GQs. These findings pave the way for further studies of GQ structures formed by pathologically related long C9-HRE sequences, and also provide a natural small-molecule ligand that modulates the structure and stability of C9-HRE GQ, both in DNA and RNA levels. Altogether, this work may contribute to therapeutic approaches of C9ALS/FTD which take the upstream C9-HRE DNA region, as well as the toxic C9-HRE RNA, as targets.
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Affiliation(s)
- Yun Zhang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Junliu Huang
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Kainan Yu
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
| | - Xiaojie Cui
- College of Life and Environmental Sciences, Minzu University of China, Beijing 100081, China
- Key Laboratory of Ecology and Environment in Minority Areas (Minzu University of China), National Ethnic Affairs Commission, Beijing 100081, China
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9
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Hernández Bustos A, Martiny E, Bom Pedersen N, Parvathaneni RP, Hansen J, Ji HP, Astakhova K. Short Tandem Repeat DNA Profiling Using Perylene-Oligonucleotide Fluorescence Assay. Anal Chem 2023; 95:7872-7879. [PMID: 37183373 DOI: 10.1021/acs.analchem.3c00063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We report an amplification-free genotyping method to determine the number of human short tandem repeats (STRs). DNA-based STR profiling is a robust method for genetic identification purposes such as forensics and biobanking and for identifying specific molecular subtypes of cancer. STR detection requires polymerase amplification, which introduces errors that obscure the correct genotype. We developed a new method that requires no polymerase. First, we synthesized perylene-nucleoside reagents and incorporated them into oligonucleotide probes that recognize five common human STRs. Using these probes and a bead-based hybridization approach, accurate STR detection was achieved in only 1.5 h, including DNA preparation steps, with up to a 1000-fold target DNA enrichment. This method was comparable to PCR-based assays. Using standard fluorometry, the limit of detection was 2.00 ± 0.07 pM for a given target. We used this assay to accurately identify STRs from 50 human subjects, achieving >98% consensus with sequencing data for STR genotyping.
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Affiliation(s)
- Adrián Hernández Bustos
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
| | - Elisa Martiny
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
| | - Nadia Bom Pedersen
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
| | - Rohith Pavan Parvathaneni
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
| | - Jonas Hansen
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
- School of Medicine, Stanford University, 94305 Stanford, California, United States
| | - Hanlee P Ji
- School of Medicine, Stanford University, 94305 Stanford, California, United States
| | - Kira Astakhova
- Department of Chemistry, Technical University of Denmark, Kongens Lyngby, Region Hovedstaden 2800, Denmark
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10
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Teng Y, Zhu M, Qiu Z. G-Quadruplexes in Repeat Expansion Disorders. Int J Mol Sci 2023; 24:ijms24032375. [PMID: 36768697 PMCID: PMC9916761 DOI: 10.3390/ijms24032375] [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: 12/29/2022] [Revised: 01/19/2023] [Accepted: 01/23/2023] [Indexed: 01/27/2023] Open
Abstract
The repeat expansions are the main genetic cause of various neurodegeneration diseases. More than ten kinds of repeat sequences with different lengths, locations, and structures have been confirmed in the past two decades. G-rich repeat sequences, such as CGG and GGGGCC, are reported to form functional G-quadruplexes, participating in many important bioprocesses. In this review, we conducted an overview concerning the contribution of G-quadruplex in repeat expansion disorders and summarized related mechanisms in current pathological studies, including the increasing genetic instabilities in replication and transcription, the toxic RNA foci formed in neurons, and the loss/gain function of proteins and peptides. Furthermore, novel strategies targeting G-quadruplex repeats were developed based on the understanding of disease mechanism. Small molecules and proteins binding to G-quadruplex in repeat expansions were investigated to protect neurons from dysfunction and delay the progression of neurodegeneration. In addition, the effects of environment on the stability of G-quadruplex were discussed, which might be critical factors in the pathological study of repeat expansion disorders.
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11
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Cheng A, Liu C, Ye W, Huang D, She W, Liu X, Fung CP, Xu N, Suen MC, Ye W, Sung HHY, Williams ID, Zhu G, Qian PY. Selective C9orf72 G-Quadruplex-Binding Small Molecules Ameliorate Pathological Signatures of ALS/FTD Models. J Med Chem 2022; 65:12825-12837. [PMID: 36226410 PMCID: PMC9574859 DOI: 10.1021/acs.jmedchem.2c00654] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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The G-quadruplex (G4) forming C9orf72 GGGGCC (G4C2) expanded hexanucleotide repeat (EHR)
is the predominant genetic cause of amyotrophic lateral sclerosis
(ALS) and frontotemporal dementia (FTD). Developing selective G4-binding
ligands is challenging due to the conformational polymorphism and
similarity of G4 structures. We identified three first-in-class marine
natural products, chrexanthomycin A (cA), chrexanthomycin
B (cB), and chrexanthomycin C (cC), with
remarkable bioactivities. Thereinto, cA shows the highest
permeability and lowest cytotoxicity to live cells. NMR titration
experiments and in silico analysis demonstrate that cA, cB, and cC selectively bind
to DNA and RNA G4C2 G4s. Notably, cA and cC dramatically reduce G4C2 EHR-caused cell death, diminish G4C2 RNA
foci in (G4C2)29-expressing Neuro2a cells, and significantly
eliminate ROS in HT22 cells. In (G4C2)29-expressing Drosophila, cA and cC significantly
rescue eye degeneration and improve locomotor deficits. Overall, our
findings reveal that cA and cC are potential
therapeutic agents deserving further clinical study.
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Affiliation(s)
- Aifang Cheng
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Changdong Liu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Shenzhen Research Institute, The Hong Kong University of Science and Technology, Hi-Tech Park, Nanshan, Shenzhen 518057, China
| | - Wenkang Ye
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China
| | - Duli Huang
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Weiyi She
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
- SZU-HKUST Joint Ph.D. Program in Marine Environmental Science, Shenzhen University, Shenzhen 518060, China
| | - Xin Liu
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Chun Po Fung
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Naining Xu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Department of Oral and Maxillofacial Surgery, Stomatological Center, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen 518036, China
| | - Monica Ching Suen
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Wei Ye
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
| | - Herman Ho Yung Sung
- Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Ian Duncan Williams
- Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong 999077, China
| | - Guang Zhu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Shenzhen Research Institute, The Hong Kong University of Science and Technology, Hi-Tech Park, Nanshan, Shenzhen 518057, China
| | - Pei-Yuan Qian
- Department of Ocean Science and Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), The Hong Kong University of Science and Technology, Hong Kong 999077, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China
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12
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Guo P, Han D. Targeting Pathogenic DNA and RNA Repeats: A Conceptual Therapeutic Way for Repeat Expansion Diseases. Chemistry 2022; 28:e202201749. [PMID: 35727679 DOI: 10.1002/chem.202201749] [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: 06/07/2022] [Indexed: 11/06/2022]
Abstract
Expansions of short tandem repeats (STRs) in the human genome cause nearly 50 neurodegenerative diseases, which are mostly inheritable, nonpreventable and incurable, posing as a huge threat to human health. Non-B DNAs formed by STRs are thought to be structural intermediates that can cause repeat expansions. The subsequent transcripts harboring expanded RNA repeats can further induce cellular toxicity through forming specific structures. Direct targeting of these pathogenic DNA and RNA repeats has emerged as a new potential therapeutic strategy to cure repeat expansion diseases. In this conceptual review, we first introduce the roles of DNA and RNA structures in the genetic instabilities and pathomechanisms of repeat expansion diseases, then describe structural features of DNA and RNA repeats with a focus on the tertiary structures determined by X-ray crystallography and solution nuclear magnetic resonance spectroscopy, and finally discuss recent progress and perspectives of developing chemical tools that target pathogenic DNA and RNA repeats for curing repeat expansion diseases.
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Affiliation(s)
- Pei Guo
- The Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital), Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang, 310022, P. R. China
| | - Da Han
- The Cancer Hospital of the University of Chinese Academy of Sciences, Zhejiang Cancer Hospital), Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, Zhejiang, 310022, P. R. China.,Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, State Key Laboratory of Oncogenes and Related Genes, Renji Hospital, School of Medicine Shanghai Jiao Tong University, Shanghai, 200127, P. R. China
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13
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McQuaid KT, Takahashi S, Baumgaertner L, Cardin DJ, Paterson NG, Hall JP, Sugimoto N, Cardin CJ. Ruthenium Polypyridyl Complex Bound to a Unimolecular Chair-Form G-Quadruplex. J Am Chem Soc 2022; 144:5956-5964. [PMID: 35324198 PMCID: PMC8991003 DOI: 10.1021/jacs.2c00178] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
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The DNA G-quadruplex
is known for forming a range of topologies
and for the observed lability of the assembly, consistent with its
transient formation in live cells. The stabilization of a particular
topology by a small molecule is of great importance for therapeutic
applications. Here, we show that the ruthenium complex Λ-[Ru(phen)2(qdppz)]2+ displays enantiospecific G-quadruplex
binding. It crystallized in 1:1 stoichiometry with a modified human
telomeric G-quadruplex sequence, GGGTTAGGGTTAGGGTTTGGG (htel21T18), in an antiparallel chair topology, the first structurally
characterized example of ligand binding to this topology. The lambda
complex is bound in an intercalation cavity created by a terminal
G-quartet and the central narrow lateral loop formed by T10–T11–A12. The two remaining wide
lateral loops are linked through a third K+ ion at the
other end of the G-quartet stack, which also coordinates three thymine
residues. In a comparative ligand-binding study, we showed, using
a Klenow fragment assay, that this complex is the strongest observed
inhibitor of replication, both using the native human telomeric sequence
and the modified sequence used in this work.
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Affiliation(s)
- Kane T McQuaid
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, U.K
| | - Shuntaro Takahashi
- FIBER (Frontier Institute for Biomolecular Engineering Research), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Lena Baumgaertner
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, U.K
| | - David J Cardin
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, U.K
| | - Neil G Paterson
- Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K
| | - James P Hall
- School of Pharmacy, University of Reading, Whiteknights, Reading RG6 6AD, U.K
| | - Naoki Sugimoto
- FIBER (Frontier Institute for Biomolecular Engineering Research), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan.,FIRST (Graduate School of Frontiers of Innovative Research in Science and Technology), Konan University, 7-1-20 Minatojima-Minamimashi, Chuo-Ku, Kobe 650-0047, Japan
| | - Christine J Cardin
- Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, U.K
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14
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Beseiso D, Chen EV, McCarthy SE, Martin KN, Gallagher EP, Miao J, Yatsunyk L. OUP accepted manuscript. Nucleic Acids Res 2022; 50:2959-2972. [PMID: 35212369 PMCID: PMC8934647 DOI: 10.1093/nar/gkac091] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 01/26/2022] [Accepted: 01/28/2022] [Indexed: 11/13/2022] Open
Abstract
G-quadruplexes (GQs) are non-canonical DNA structures composed of stacks of stabilized G-tetrads. GQs play an important role in a variety of biological processes and may form at telomeres and oncogene promoters among other genomic locations. Here, we investigate nine variants of telomeric DNA from Tetrahymena thermophila with the repeat (TTGGGG)n. Biophysical data indicate that the sequences fold into stable four-tetrad GQs which adopt multiple conformations according to native PAGE. Excitingly, we solved the crystal structure of two variants, TET25 and TET26. The two variants differ by the presence of a 3′-T yet adopt different GQ conformations. TET25 forms a hybrid [3 + 1] GQ and exhibits a rare 5′-top snapback feature. Consequently, TET25 contains four loops: three lateral (TT, TT, and GTT) and one propeller (TT). TET26 folds into a parallel GQ with three TT propeller loops. To the best of our knowledge, TET25 and TET26 are the first reported hybrid and parallel four-tetrad unimolecular GQ structures. The results presented here expand the repertoire of available GQ structures and provide insight into the intricacy and plasticity of the 3D architecture adopted by telomeric repeats from T. thermophila and GQs in general.
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Affiliation(s)
- Dana Beseiso
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Erin V Chen
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Sawyer E McCarthy
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Kailey N Martin
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Elizabeth P Gallagher
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Joanne Miao
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
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15
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Ozcan KA, Ghaffari LT, Haeusler AR. The effects of molecular crowding and CpG hypermethylation on DNA G-quadruplexes formed by the C9orf72 nucleotide repeat expansion. Sci Rep 2021; 11:23213. [PMID: 34853325 PMCID: PMC8636472 DOI: 10.1038/s41598-021-02041-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 11/09/2021] [Indexed: 01/09/2023] Open
Abstract
A nucleotide repeat expansion (NRE), (G4C2)n, located in a classically noncoding region of C9orf72 (C9), is the most common genetic mutation associated with ALS/FTD. There is increasing evidence that nucleic acid structures formed by the C9-NRE may both contribute to ALS/FTD, and serve as therapeutic targets, but there is limited characterization of these nucleic acid structures under physiologically and disease relevant conditions. Here we show in vitro that the C9-NRE DNA can form both parallel and antiparallel DNA G-quadruplex (GQ) topological structures and that the structural preference of these DNA GQs can be dependent on the molecular crowding conditions. Additionally, 5-methylcytosine DNA hypermethylation, which is observed in the C9-NRE locus in some patients, has minimal effects on GQ topological preferences. Finally, molecular dynamic simulations of methylated and nonmethylated GQ structures support in vitro data showing that DNA GQ structures formed by the C9-NRE DNA are stable, with structural fluctuations limited to the cytosine-containing loop regions. These findings provide new insight into the structural polymorphic preferences and stability of DNA GQs formed by the C9-NRE in both the methylated and nonmethylated states, as well as reveal important features to guide the development of upstream therapeutic approaches to potentially attenuate C9-NRE-linked diseases.
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Affiliation(s)
- Kadir A Ozcan
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Layla T Ghaffari
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA
| | - Aaron R Haeusler
- Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, Philadelphia, PA, USA. .,Department of Neuroscience, Jefferson Weinberg ALS Center, Vickie and Jack Farber Institute for Neuroscience, Thomas Jefferson University, 900 Walnut Street, JHN suite 410, Philadelphia, PA, 19107, USA.
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16
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Fu W, Jing H, Xu X, Xu S, Wang T, Hu W, Li H, Zhang N. Two coexisting pseudo-mirror heteromolecular telomeric G-quadruplexes in opposite loop progressions differentially recognized by a low equivalent of Thioflavin T. Nucleic Acids Res 2021; 49:10717-10734. [PMID: 34500466 PMCID: PMC8501994 DOI: 10.1093/nar/gkab755] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 07/24/2021] [Accepted: 08/31/2021] [Indexed: 11/13/2022] Open
Abstract
The final 3′-terminal residue of the telomeric DNA G-overhang is inherently less precise. Here, we describe how alteration of the last 3′-terminal base affects the mutual recognition between two different G-rich oligomers of human telomeric DNA in the formation of heteromolecular G-quadruplexes (hetero-GQs). Associations between three- and single-repeat fragments of human telomeric DNA, target d(GGGTTAGGGTTAGGG) and probe d(TAGGGT), in Na+ solution yield two coexisting forms of (3 + 1) hybrid hetero-GQs: the kinetically favourable LLP-form (left loop progression) and the thermodynamically controlled RLP-form (right loop progression). However, only the adoption of a single LLP-form has been previously reported between the same probe d(TAGGGT) and a target variant d(GGGTTAGGGTTAGGGT) having one extra 3′-end thymine. Moreover, the flanking base alterations of short G-rich probe variants also significantly affect the loop progressions of hetero-GQs. Although seemingly two pseudo-mirror counter partners, the RLP-form exhibits a preference over the LLP-form to be recognized by a low equivalent of fluorescence dye thioflavin T (ThT). To a greater extent, ThT preferentially binds to RLP hetero-GQ than with the corresponding telomeric DNA duplex context or several other representative unimolecular GQs.
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Affiliation(s)
- 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
| | - Xiaojuan Xu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Suping Xu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Tao Wang
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China
| | - Wenxuan Hu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031, China.,University of Science and Technology of China, Hefei 230026, China
| | - Huihui Li
- 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.,High Magnetic Field Laboratory of Anhui Province, Hefei 230031, China
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17
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Mohr S, Jana J, Vianney YM, Weisz K. Expanding the Topological Landscape by a G-Column Flip of a Parallel G-Quadruplex. Chemistry 2021; 27:10437-10447. [PMID: 33955615 PMCID: PMC8361731 DOI: 10.1002/chem.202101181] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Indexed: 01/14/2023]
Abstract
Canonical G‐quadruplexes can adopt a variety of different topologies depending on the arrangement of propeller, lateral, or diagonal loops connecting the four G‐columns. A novel intramolecular G‐quadruplex structure is derived through inversion of the last G‐tract of a three‐layered parallel fold, associated with the transition of a single propeller into a lateral loop. The resulting (3+1) hybrid fold features three syn⋅anti⋅anti⋅anti G‐tetrads with a 3’‐terminal all‐syn G‐column. Although the ability of forming a duplex stem‐loop between G‐tracts seems beneficial for a propeller‐to‐lateral loop rearrangement, unmodified G‐rich sequences resist folding into the new (3+1) topology. However, refolding can be driven by the incorporation of syn‐favoring guanosine analogues into positions of the fourth G‐stretch. The presented hybrid‐type G‐quadruplex structure as determined by NMR spectroscopy may provide for an additional scaffold in quadruplex‐based technologies.
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Affiliation(s)
- Swantje Mohr
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Jagannath Jana
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
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18
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Geng Y, Liu C, Cai Q, Luo Z, Miao H, Shi X, Xu N, Fung CP, Choy TT, Yan B, Li N, Qian P, Zhou B, Zhu G. Crystal structure of parallel G-quadruplex formed by the two-repeat ALS- and FTD-related GGGGCC sequence. Nucleic Acids Res 2021; 49:5881-5890. [PMID: 34048588 PMCID: PMC8191786 DOI: 10.1093/nar/gkab302] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/23/2021] [Accepted: 05/26/2021] [Indexed: 01/05/2023] Open
Abstract
The hexanucleotide repeat expansion, GGGGCC (G4C2), within the first intron of the C9orf72 gene is known to be the most common genetic cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The G4C2 repeat expansions, either DNA or RNA, are able to form G-quadruplexes which induce toxicity leading to ALS/FTD. Herein, we report a novel crystal structure of d(G4C2)2 that self-associates to form an eight-layer parallel tetrameric G-quadruplex. Two d(G4C2)2 associate together as a parallel dimeric G-quadruplex which folds into a tetramer via 5'-to-5' arrangements. Each dimer consists of four G-tetrads connected by two CC propeller loops. Especially, the 3'-end cytosines protrude out and form C·C+•C·C+/ C·C•C·C+ quadruple base pair or C•C·C+ triple base pair stacking on the dimeric block. Our work sheds light on the G-quadruplexes adopted by d(G4C2) and yields the invaluable structural details for the development of small molecules to tackle neurodegenerative diseases, ALS and FTD.
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Affiliation(s)
- Yanyan Geng
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Changdong Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Qixu Cai
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Zhipu Luo
- Institute of Molecular Enzymology, School of Biology and Basic Medical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Haitao Miao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Xiao Shi
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Naining Xu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Chun Po Fung
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - To To Choy
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Bing Yan
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Ning Li
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Peiyuan Qian
- Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Bo Zhou
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
- Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
| | - Guang Zhu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
- Hong Kong Branch of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
- State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 00000, China
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19
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Vianney YM, Weisz K. First Tandem Repeat of a Potassium Channel KCNN4 Minisatellite Folds into a V-Loop G-Quadruplex Structure. Biochemistry 2021; 60:1337-1346. [PMID: 33844501 DOI: 10.1021/acs.biochem.1c00043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The KCNN4 gene encoding a potassium channel protein whose expression has been correlated with tumor progression was found to comprise a guanine-rich minisatellite region with the ability to form a putative G-quadruplex (G4). Given the suggested regulatory role of G4s in gene expression, G-quadruplex formation for the polymorphic first repeat of the minisatellite was studied by nuclear magnetic resonance spectroscopy. A stable G-quadruplex of a truncated mutant sequence was shown to represent one of several coexisting species of the wild-type sequence. The high-resolution structure features a noncanonical G4 with a broken G-column and a V-shaped loop. The presence of a 3'-flanking thymidine interacting with the lateral loop preceding the V loop seems to be critical for the formation of this G4 topology. On the contrary, an additional 5'-flanking residue disfavored but still allowed folding into the V-loop structure. The latter may therefore serve as a putative therapeutic target in strategies for G4-based modulation of KCNN4 expression.
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Affiliation(s)
- Yoanes Maria Vianney
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Universität Greifswald, Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
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20
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Maity A, Winnerdy FR, Chen G, Phan AT. Duplexes Formed by G 4C 2 Repeats Contain Alternate Slow- and Fast-Flipping G·G Base Pairs. Biochemistry 2021; 60:1097-1107. [PMID: 33750098 DOI: 10.1021/acs.biochem.0c00916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Aberrant expansion of the hexanucleotide GGGGCC (or G4C2) repeat in the human C9ORF72 gene is the most common genetic factor found behind amyotrophic lateral sclerosis and frontotemporal dementia. The hypothesized pathways, through which the repeat expansions contribute to the pathology, involve one or more secondary structural forms of the DNA and/or RNA sequences, such as G-quadruplexes, duplexes, and hairpins. Here, we study the structures of DNA and RNA duplexes formed by G4C2 repeats, which contain G(syn)·G(anti) base pairs flanked by either G·C or C·G base pairs. We show that duplexes formed by G4C2 repeats contain alternately two types of G·G pair contexts exhibiting different syn-anti base flipping dynamics (∼100 ms vs ∼2 ms for DNA and ∼50 ms vs ∼20 ms for RNA at 10 °C, respectively) depending on the flanking bases, with the slow-flipping G·G pairs being flanked by a guanine at the 5'-end and the fast-flipping G·G pairs being flanked by a cytosine at the 5'-end. Our findings on the structures and dynamics of G·G base pairs in DNA and RNA duplexes formed by G4C2 repeats provide a foundation for further studies of the functions and targeting of such biologically relevant motifs.
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Affiliation(s)
- Arijit Maity
- 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
- NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
| | - Gang Chen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
- School of Life and Health Sciences, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), No. 2001 Longxiang Boulevard, Longgang District, Shenzhen, Guangdong 518172, P. R. China
| | - 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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21
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Lago S, Nadai M, Ruggiero E, Tassinari M, Marušič M, Tosoni B, Frasson I, Cernilogar FM, Pirota V, Doria F, Plavec J, Schotta G, Richter SN. The MDM2 inducible promoter folds into four-tetrad antiparallel G-quadruplexes targetable to fight malignant liposarcoma. Nucleic Acids Res 2021; 49:847-863. [PMID: 33410915 PMCID: PMC7826256 DOI: 10.1093/nar/gkaa1273] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 12/18/2020] [Accepted: 12/21/2020] [Indexed: 02/06/2023] Open
Abstract
Well-differentiated liposarcoma (WDLPS) is a malignant neoplasia hard to diagnose and treat. Its main molecular signature is amplification of the MDM2-containing genomic region. The MDM2 oncogene is the master regulator of p53: its overexpression enhances p53 degradation and inhibits apoptosis, leading to the tumoral phenotype. Here, we show that the MDM2 inducible promoter G-rich region folds into stable G-quadruplexes both in vitro and in vivo and it is specifically recognized by cellular helicases. Cell treatment with G-quadruplex-ligands reduces MDM2 expression and p53 degradation, thus stimulating cancer cell cycle arrest and apoptosis. Structural characterization of the MDM2 G-quadruplex revealed an extraordinarily stable, unique four-tetrad antiparallel dynamic conformation, amenable to selective targeting. These data indicate the feasibility of an out-of-the-box G-quadruplex-targeting approach to defeat WDLPS and all tumours where restoration of wild-type p53 is sought. They also point to G-quadruplex-dependent genomic instability as possible cause of MDM2 expansion and WDLPS tumorigenesis.
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Affiliation(s)
- Sara Lago
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Matteo Nadai
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Emanuela Ruggiero
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Martina Tassinari
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Maja Marušič
- Slovenian NMR center, National Institute of Chemistry, Hajdrihova, 19, Ljubljana SI-1000, Slovenia
| | - Beatrice Tosoni
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Ilaria Frasson
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
| | - Filippo M Cernilogar
- Division of Molecular Biology, Biomedical Center, Faculty of Medicine, LMU Munich, Germany
| | - Valentina Pirota
- Department of Chemistry, University of Pavia, V. le Taramelli 10, 27100, Pavia, Italy
| | - Filippo Doria
- Department of Chemistry, University of Pavia, V. le Taramelli 10, 27100, Pavia, Italy
| | - Janez Plavec
- Slovenian NMR center, National Institute of Chemistry, Hajdrihova, 19, Ljubljana SI-1000, Slovenia
| | - Gunnar Schotta
- Division of Molecular Biology, Biomedical Center, Faculty of Medicine, LMU Munich, Germany
| | - Sara N Richter
- Department of Molecular Medicine, University of Padua, via A. Gabelli 63, 35121 Padua, Italy
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22
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Kuznetsova AA, Fedorova OS, Kuznetsov NA. Lesion Recognition and Cleavage of Damage-Containing Quadruplexes and Bulged Structures by DNA Glycosylases. Front Cell Dev Biol 2020; 8:595687. [PMID: 33330484 PMCID: PMC7734321 DOI: 10.3389/fcell.2020.595687] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/10/2020] [Indexed: 12/22/2022] Open
Abstract
Human telomeres as well as more than 40% of human genes near the promoter regions have been found to contain the sequence that may form a G-quadruplex structure. Other non-canonical DNA structures comprising bulges, hairpins, or bubbles may have a functionally important role during transcription, replication, or recombination. The guanine-rich regions of DNA are hotspots of oxidation that forms 7,8-dihydro-8-oxoguanine, thymine glycol, and abasic sites: the lesions that are handled by the base excision repair pathway. Nonetheless, the features of DNA repair processes in non-canonical DNA structures are still poorly understood. Therefore, in this work, a comparative analysis of the efficiency of the removal of a damaged nucleotide from various G-quadruplexes and bulged structures was performed using endonuclease VIII-like 1 (NEIL1), human 8-oxoguanine-DNA glycosylase (OGG1), endonuclease III (NTH1), and prokaryotic formamidopyrimidine-DNA glycosylase (Fpg), and endonuclease VIII (Nei). All the tested enzymes were able to cleave damage-containing bulged DNA structures, indicating their important role in the repair process when single-stranded DNA and intermediate non–B-form structures such as bubbles and bulges are formed. Nevertheless, our results suggest that the ability to cleave damaged quadruplexes is an intrinsic feature of members of the H2tH structural family, suggesting that these enzymes can participate in the modulation of processes controlled by the formation of quadruplex structures in genomic DNA.
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Affiliation(s)
| | - Olga S Fedorova
- Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Nikita A Kuznetsov
- Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
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23
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Murat P, Guilbaud G, Sale JE. DNA polymerase stalling at structured DNA constrains the expansion of short tandem repeats. Genome Biol 2020; 21:209. [PMID: 32819438 PMCID: PMC7441554 DOI: 10.1186/s13059-020-02124-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 07/28/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Short tandem repeats (STRs) contribute significantly to de novo mutagenesis, driving phenotypic diversity and genetic disease. Although highly diverse, their repetitive sequences induce DNA polymerase slippage and stalling, leading to length and sequence variation. However, current studies of DNA synthesis through STRs are restricted to a handful of selected sequences, limiting our broader understanding of their evolutionary behaviour and hampering the characterisation of the determinants of their abundance and stability in eukaryotic genomes. RESULTS We perform a comprehensive analysis of DNA synthesis at all STR permutations and interrogate the impact of STR sequence and secondary structure on their genomic representation and mutability. To do this, we developed a high-throughput primer extension assay that allows monitoring of the kinetics and fidelity of DNA synthesis through 20,000 sequences comprising all STR permutations in different lengths. By combining these measurements with population-scale genomic data, we show that the response of a model replicative DNA polymerase to variously structured DNA is sufficient to predict the complex genomic behaviour of STRs, including abundance and mutational constraints. We demonstrate that DNA polymerase stalling at DNA structures induces error-prone DNA synthesis, which constrains STR expansion. CONCLUSIONS Our data support a model in which STR length in eukaryotic genomes results from a balance between expansion due to polymerase slippage at repeated DNA sequences and point mutations caused by error-prone DNA synthesis at DNA structures.
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Affiliation(s)
- Pierre Murat
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
| | - Guillaume Guilbaud
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Julian E Sale
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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24
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Chasing Particularities of Guanine- and Cytosine-Rich DNA Strands. Molecules 2020; 25:molecules25030434. [PMID: 31972988 PMCID: PMC7037129 DOI: 10.3390/molecules25030434] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/17/2020] [Accepted: 01/20/2020] [Indexed: 01/17/2023] Open
Abstract
By substitution of natural nucleotides by their abasic analogs (i.e., 1',2'-dideoxyribose phosphate residue) at critically chosen positions within 27-bp DNA constructs originating from the first intron of N-myc gene, we hindered hybridization within the guanine- and cytosine-rich central region and followed formation of non-canonical structures. The impeded hybridization between the complementary strands leads to time-dependent structural transformations of guanine-rich strand that are herein characterized with the use of solution-state NMR, CD spectroscopy, and native polyacrylamide gel electrophoresis. Moreover, the DNA structural changes involve transformation of intra- into inter-molecular G-quadruplex structures that are thermodynamically favored. Intriguingly, the transition occurs in the presence of complementary cytosine-rich strands highlighting the inability of Watson-Crick base-pairing to preclude the transformation between G-quadruplex structures that occurs via intertwining mechanism and corroborates a role of G-quadruplex structures in DNA recombination processes.
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25
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Mulholland K, Sullivan HJ, Garner J, Cai J, Chen B, Wu C. Three-Dimensional Structure of RNA Monomeric G-Quadruplex Containing ALS and FTD Related G4C2 Repeat and Its Binding with TMPyP4 Probed by Homology Modeling based on Experimental Constraints and Molecular Dynamics Simulations. ACS Chem Neurosci 2020; 11:57-75. [PMID: 31800202 DOI: 10.1021/acschemneuro.9b00572] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The G-quadruplex-forming hexanucleotide repeat expansion (HRE), d(G4C2)n, within the human C9orf72 gene is the root cause for familial amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD). A recent study has shown that TMPyP4 has good potential to work as a RNA G-quadruplex binder in treating ALS and FTD. Although the high-resolution structure of the monomeric DNA antiparallel G-quadruplex form of the monomeric hexanucleotide repeat was recently solved, the RNA parallel G-quadruplex structure and its complex with TMPyP4 are not available yet. In this study, we first constructed the homology model for the parallel monomeric RNA G-quadruplex of r(G4C2)3G4 based on experimental constraints and the parallel monomeric G-quadruplex DNA crystal structure. Although the G-tetra core of the homology model was stable observed in 15 μs molecular dynamics (MD) simulations, we observed that the loops adopt additional conformations besides the initial crystal conformation, where TMPyP4 binding was found to reduce the loop fluctuation of the RNA monomeric G-quadruplex. Next, we probed the elusive binding behavior of TMPyP4 to the RNA monomeric G-quadruplex. Encouragingly, the binding modes observed are similar to the modes observed in two experimental complexes of a parallel DNA G-quadruplex with TMPyP4. We also constructed a Markov state model to provide insights into the binding pathways. Together, the findings from our study may assist future development of G-quadruplex-specific ligands in the treatment of neurodegenerative diseases like ALS and FTD.
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Affiliation(s)
- Kelly Mulholland
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Holli-Joi Sullivan
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Joseph Garner
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Jun Cai
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Brian Chen
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
| | - Chun Wu
- College of Science and Mathematics, Rowan University, Glassboro, New Jersey 08028, United States
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26
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Lu Y, Dohno C, Nakatani K. A novel naphthyridine tetramer that recognizes tandem G–G mismatches by the formation of an interhelical complex. Chem Commun (Camb) 2020; 56:754-757. [DOI: 10.1039/c9cc08111a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel naphthyridine tetramer, p-NCTB, was reported to bind two distal CGGG/CGGG via noncovalent binding forming inter- and intrastrand complexes.
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Affiliation(s)
- Yihuan Lu
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki 567-0047
- Japan
| | - Chikara Dohno
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki 567-0047
- Japan
| | - Kazuhiko Nakatani
- The Institute of Scientific and Industrial Research
- Osaka University
- Ibaraki 567-0047
- Japan
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27
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Geng Y, Liu C, Zhou B, Cai Q, Miao H, Shi X, Xu N, You Y, Fung CP, Din RU, Zhu G. The crystal structure of an antiparallel chair-type G-quadruplex formed by Bromo-substituted human telomeric DNA. Nucleic Acids Res 2019; 47:5395-5404. [PMID: 30957851 PMCID: PMC6547763 DOI: 10.1093/nar/gkz221] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/18/2019] [Accepted: 04/04/2019] [Indexed: 12/28/2022] Open
Abstract
Human telomeric guanine-rich DNA, which could adopt different G-quadruplex structures, plays important roles in protecting the cell from recombination and degradation. Although many of these structures were determined, the chair-type G-quadruplex structure remains elusive. Here, we present a crystal structure of the G-quadruplex composed of the human telomeric sequence d[GGGTTAGG8GTTAGGGTTAGG20G] with two dG to 8Br-dG substitutions at positions 8 and 20 with syn conformation in the K+ solution. It forms a novel three-layer chair-type G-quadruplex with two linking trinucleotide loops. Particularly, T5 and T17 are coplanar with two water molecules stacking on the G-tetrad layer in a sandwich-like mode through a coordinating K+ ion and an A6•A18 base pair. While a twisted Hoogsteen A12•T10 base pair caps on the top of G-tetrad core. The three linking TTA loops are edgewise and each DNA strand has two antiparallel adjacent strands. Our findings contribute to a deeper understanding and highlight the unique roles of loop and water molecule in the folding of the G-quadruplex.
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Affiliation(s)
- Yanyan Geng
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Changdong Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Bo Zhou
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.,Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Qixu Cai
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Haitao Miao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Xiao Shi
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Naining Xu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Yingying You
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Chun Po Fung
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Rahman Ud Din
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Guang Zhu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China.,State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
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28
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Guédin A, Lin LY, Armane S, Lacroix L, Mergny JL, Thore S, Yatsunyk LA. Quadruplexes in 'Dicty': crystal structure of a four-quartet G-quadruplex formed by G-rich motif found in the Dictyostelium discoideum genome. Nucleic Acids Res 2019; 46:5297-5307. [PMID: 29718337 PMCID: PMC6007418 DOI: 10.1093/nar/gky290] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/06/2018] [Indexed: 11/25/2022] Open
Abstract
Guanine-rich DNA has the potential to fold into non-canonical G-quadruplex (G4) structures. Analysis of the genome of the social amoeba Dictyostelium discoideum indicates a low number of sequences with G4-forming potential (249–1055). Therefore, D. discoideum is a perfect model organism to investigate the relationship between the presence of G4s and their biological functions. As a first step in this investigation, we crystallized the dGGGGGAGGGGTACAGGGGTACAGGGG sequence from the putative promoter region of two divergent genes in D. discoideum. According to the crystal structure, this sequence folds into a four-quartet intramolecular antiparallel G4 with two lateral and one diagonal loops. The G-quadruplex core is further stabilized by a G-C Watson–Crick base pair and a A–T–A triad and displays high thermal stability (Tm > 90°C at 100 mM KCl). Biophysical characterization of the native sequence and loop mutants suggests that the DNA adopts the same structure in solution and in crystalline form, and that loop interactions are important for the G4 stability but not for its folding. Four-tetrad G4 structures are sparse. Thus, our work advances understanding of the structural diversity of G-quadruplexes and yields coordinates for in silico drug screening programs and G4 predictive tools.
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Affiliation(s)
- Aurore Guédin
- ARNA Laboratory, Inserm U1212, CNRS UMR 5320, Université de Bordeaux, Bordeaux, France
| | | | - Samir Armane
- ARNA Laboratory, Inserm U1212, CNRS UMR 5320, Université de Bordeaux, Bordeaux, France
| | | | - Jean-Louis Mergny
- ARNA Laboratory, Inserm U1212, CNRS UMR 5320, Université de Bordeaux, Bordeaux, France.,Institute of Biophysics of the CAS, v.v.i., Kraálovopolskaá 135, 612 65 Brno, Czech Republic
| | - Stéphane Thore
- ARNA Laboratory, Inserm U1212, CNRS UMR 5320, Université de Bordeaux, Bordeaux, France
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29
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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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30
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Brcic J, Plavec J. NMR structure of a G-quadruplex formed by four d(G4C2) repeats: insights into structural polymorphism. Nucleic Acids Res 2019; 46:11605-11617. [PMID: 30277522 PMCID: PMC6265483 DOI: 10.1093/nar/gky886] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/19/2018] [Indexed: 12/13/2022] Open
Abstract
Most frequent genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), is a largely increased number of d(G4C2)n•(G2C4)n repeats located in the non-coding region of C9orf72 gene. Non-canonical structures, including G-quadruplexes, formed within expanded repeats have been proposed to drive repeat expansion and pathogenesis of ALS and FTD. Oligonucleotide d[(G4C2)3G4], which represents the shortest oligonucleotide model of d(G4C2) repeats with the ability to form a unimolecular G-quadruplex, forms two major G-quadruplex structures in addition to several minor species which coexist in solution with K+ ions. Herein, we used solution-state NMR to determine the high-resolution structure of one of the major G-quadruplex species adopted by d[(G4C2)3G4]. Structural characterization of the G-quadruplex named AQU was facilitated by a single substitution of dG with 8Br-dG at position 21 and revealed an antiparallel fold composed of four G-quartets and three lateral C-C loops. The G-quadruplex exhibits high thermal stability and is favored kinetically and under slightly acidic conditions. An unusual structural element distinct from a C-quartet is observed in the structure. Two C•C base pairs are stacked on the nearby G-quartet and are involved in a dynamic equilibrium between symmetric N3-amino and carbonyl-amino geometries and protonated C+•C state.
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Affiliation(s)
- Jasna Brcic
- Slovenian NMR Center, National Institute of Chemistry, Ljubljana SI-1000, Slovenia
| | - Janez Plavec
- Slovenian NMR Center, National Institute of Chemistry, Ljubljana SI-1000, Slovenia.,Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana SI-1000, Slovenia.,EN-FIST Center of Excellence, Ljubljana SI-1000, Slovenia
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31
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O'Hagan MP, Morales JC, Galan MC. Binding and Beyond: What Else Can G-Quadruplex Ligands Do? European J Org Chem 2019. [DOI: 10.1002/ejoc.201900692] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | - Juan C. Morales
- Instituto de Parasitología y Biomedicina “López Neyra”; Consejo Superior de Investigaciones Científicas (CSIC); PTS Granada; Avenida del Conocimiento 17 18016 Armilla, Granada Spain
| | - M. Carmen Galan
- School of Chemistry; University of Bristol; Cantock's Close BS8 1TS UK
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32
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Liu C, Geng Y, Miao H, Shi X, You Y, Xu N, Zhou B, Zhu G. G-quadruplex structures formed by human telomeric DNA and C9orf72 hexanucleotide repeats. Biophys Rev 2019; 11:389-393. [PMID: 31127470 DOI: 10.1007/s12551-019-00545-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 04/30/2019] [Indexed: 02/04/2023] Open
Affiliation(s)
- Changdong Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Yanyan Geng
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Haitao Miao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Xiao Shi
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Yingying You
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Naining Xu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Bo Zhou
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China
| | - Guang Zhu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, SAR, China.
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33
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Towards Understanding of Polymorphism of the G-rich Region of Human Papillomavirus Type 52. Molecules 2019; 24:molecules24071294. [PMID: 30987050 PMCID: PMC6479982 DOI: 10.3390/molecules24071294] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 03/29/2019] [Accepted: 03/31/2019] [Indexed: 11/17/2022] Open
Abstract
The potential to affect gene expression via G-quadruplex stabilization has been extended to all domains of life, including viruses. Here, we investigate the polymorphism and structures of G-quadruplexes of the human papillomavirus type 52 with UV, CD and NMR spectroscopy and gel electrophoresis. We show that oligonucleotide with five G-tracts folds into several structures and that naturally occurring single nucleotide polymorphisms (SNPs) have profound effects on the structural polymorphism in the context of G-quadruplex forming propensity, conformational heterogeneity and folding stability. With help of SNP analysis, we were able to select one of the predominant forms, formed by G-rich sequence d(G₃TAG₃CAG₄ACACAG₃T). This oligonucleotide termed HPV52(1-4) adopts a three G-quartet snap back (3 + 1) type scaffold with four syn guanine residues, two edgewise loops spanning the same groove, a no-residue V loop and a propeller type loop. The first guanine residue is incorporated in the central G-quartet and all four-guanine residues from G4 stretch are included in the three quartet G-quadruplex core. Modification studies identified several structural elements that are important for stabilization of the described G-quadruplex fold. Our results expand set of G-rich targets in viral genomes and address the fundamental questions regarding folding of G-rich sequences.
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34
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Liu C, Zhou B, Geng Y, Yan Tam D, Feng R, Miao H, Xu N, Shi X, You Y, Hong Y, Tang BZ, Kwan Lo P, Kuryavyi V, Zhu G. A chair-type G-quadruplex structure formed by a human telomeric variant DNA in K + solution. Chem Sci 2019; 10:218-226. [PMID: 30713633 PMCID: PMC6330691 DOI: 10.1039/c8sc03813a] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 10/03/2018] [Indexed: 01/15/2023] Open
Abstract
Guanine tracts of human telomeric DNA sequences are known to fold into eight different four-stranded structures that vary by the conformation of guanine nucleotides arranged in the stack of G-tetrads in their core and by different kinds and orders of connecting loops, called G-quadruplexes. Here, we present a novel G-quadruplex structure formed in K+ solution by a human telomeric variant d[(GGGTTA)2GGGTTTGGG], htel21T18. This variant DNA is located in the subtelomeric regions of human chromosomes 8, 11, 17, and 19 as well as in the DNase hypersensitive region and in the subcentromeric region of chromosome 5. Interestingly, single A18T substitution that makes htel21T18 different from the human telomeric sequence results in the formation of a three-layer chair-type G-quadruplex, a fold previously unknown among human telomeric repeats, with two loops interacting through the reverse Watson-Crick A6·T18 base pair. The loops are edgewise; glycosidic conformation of guanines is syn·anti·syn·anti around each tetrad, and each strand of the core has two antiparallel adjacent strands. Our results expand the repertoire of known G-quadruplex folding topologies and may provide a potential target for structure-based anticancer drug design.
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Affiliation(s)
- Changdong Liu
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Bo Zhou
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
- Institute for Advanced Study , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China
| | - Yanyan Geng
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Dick Yan Tam
- Department of Biology and Chemistry , City University of Hong Kong , 83 Tat Chee Avenue , Kowloon Tong , Hong Kong SAR , China
| | - Rui Feng
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Haitao Miao
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Naining Xu
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Xiao Shi
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Yingying You
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
| | - Yuning Hong
- Department of Chemistry , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China
| | - Ben Zhong Tang
- Department of Chemistry , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China
| | - Pik Kwan Lo
- Department of Biology and Chemistry , City University of Hong Kong , 83 Tat Chee Avenue , Kowloon Tong , Hong Kong SAR , China
| | - Vitaly Kuryavyi
- Structural Biology Program , Memorial Sloan-Kettering Cancer Center , New York , NY , USA .
| | - Guang Zhu
- Division of Life Science , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China .
- Institute for Advanced Study and State Key Laboratory of Molecular Neuroscience , The Hong Kong University of Science and Technology , Clear Water Bay , Kowloon , Hong Kong SAR , China
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35
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Liao TC, Ma TZ, Liang Z, Zhang XT, Luo CY, Liu L, Zhou CQ. A Comparative Study on High Selectivities of Human Telomeric Dimeric G-Quadruplexes by Dimeric G-Quadruplex Binders. Chemistry 2018; 24:15840-15851. [DOI: 10.1002/chem.201802796] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 07/18/2018] [Indexed: 01/02/2023]
Affiliation(s)
- Ting-Cong Liao
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Tian-Zhu Ma
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Zhi Liang
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Xin-Tong Zhang
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Chun-Yin Luo
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Lihong Liu
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
| | - Chun-Qiong Zhou
- Guangdong Provincial Key Laboratory of New Drug Screening; School of Pharmaceutical Sciences; Southern Medical University; Guangzhou 510515 P. R. China
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36
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Li Z, Li L, Zheng Y, Chen C, Sun T. Diagnostic absolute configuration determination of clavulanate potassium: A comprehensive investigation of chiroptical spectroscopies and theoretical calculations. J Pharm Biomed Anal 2018; 160:351-359. [DOI: 10.1016/j.jpba.2018.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 07/12/2018] [Accepted: 08/05/2018] [Indexed: 10/28/2022]
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Dvorkin SA, Karsisiotis AI, Webba da Silva M. Encoding canonical DNA quadruplex structure. SCIENCE ADVANCES 2018; 4:eaat3007. [PMID: 30182059 PMCID: PMC6118410 DOI: 10.1126/sciadv.aat3007] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 07/24/2018] [Indexed: 05/24/2023]
Abstract
The main challenge in DNA quadruplex design is to encode a three-dimensional structure into the primary sequence, despite its multiple, repetitive guanine segments. We identify and detail structural elements describing all 14 feasible canonical quadruplex scaffolds and demonstrate their use in control of design. This work outlines a new roadmap for implementation of targeted design of quadruplexes for material, biotechnological, and therapeutic applications.
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Affiliation(s)
- Scarlett A. Dvorkin
- School of Pharmacy and Pharmaceutical Sciences, Biomedical Sciences Research Institute, Ulster University, Coleraine BT52 1SA, UK
| | - Andreas I. Karsisiotis
- School of Pharmacy and Pharmaceutical Sciences, Biomedical Sciences Research Institute, Ulster University, Coleraine BT52 1SA, UK
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Karg B, Weisz K. Loop Length Affects Syn-Anti Conformational Rearrangements in Parallel G-Quadruplexes. Chemistry 2018; 24:10246-10252. [PMID: 29756658 DOI: 10.1002/chem.201801851] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 05/12/2018] [Indexed: 01/24/2023]
Abstract
A G-quadruplex forming sequence from the MYC promoter region was modified with syn-favoring 8-bromo-2'-deoxyguanosine residues. Depending on the number and position of modifications in the intramolecular parallel G-quadruplex, substitutions with the bromoguanosine analogue at the 5'-tetrad induce conformational rearrangements with concerted all-anti to all-syn transitions for all residues of the modified G-quartet. No unfavorable steric interactions of the C8-substituents in the medium grooves are apparent in the high-resolution structure as determined for a tetrasubstituted MYC quadruplex that exclusively forms the all-syn isomer. In contrast, considerable steric clashes with 5'-phosphate oxygen atoms for those analogues that follow a less flexible 1-nucleotide loop in the native all-anti conformation seem to constitute the major driving force for the tetrad inversion and allow for the rational design of appropriately substituted sequences. Correlations found between the population of species subjected to a tetrad flip and melting temperatures indicate that more effective conformational transitions are compromised by lower thermal stabilities of the modified parallel quadruplexes.
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Affiliation(s)
- Beatrice Karg
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald, Felix-Hausdorff-Str. 4, 17487, Greifswald, Germany
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39
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Zhang Y, Roland C, Sagui C. Structural and Dynamical Characterization of DNA and RNA Quadruplexes Obtained from the GGGGCC and GGGCCT Hexanucleotide Repeats Associated with C9FTD/ALS and SCA36 Diseases. ACS Chem Neurosci 2018; 9:1104-1117. [PMID: 29281254 PMCID: PMC6442734 DOI: 10.1021/acschemneuro.7b00476] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
A (GGGGCC) hexanucleotide repeat (HR) expansion in the C9ORF72 gene has been considered the major cause behind both frontotemporal dementia and amyotrophic lateral sclerosis, while a (GGGCCT) is associated with spinocerebellar ataxia 36. Recent experiments involving NMR, CD, optical melting and 1D 1H NMR spectroscopy, suggest that the r(GGGGCC) HR can adopt a hairpin structure with G-G mismatches in equilibrium with a G-quadruplex structure. G-Quadruplexes have also been identified for d(GGGGCC). As these experiments lack molecular resolution, we have used molecular dynamics microsecond simulations to obtain a structural characterization of the G-quadruplexes associated with both HRs. All DNA G-quadruplexes, parallel or antiparallel, with or without loops are stable, while only parallel and one antiparallel (stabilized by diagonal loops) RNA G-quadruplexes are stable. It is known that antiparallel G-quadruplexes require alternating guanines to be in a syn conformation that is hindered by the C3'-endo pucker preferred by RNA. Initial RNA antiparallel quadruplexes built with C2'-endo sugars evolve such that the transition (C2'-endo)-to-(C3'-endo) triggers unwinding and buckling of the flat G-tetrads, resulting in the unfolding of the RNA antiparallel quadruplex. Finally, a parallel G-quadruplex stabilizes an adjacent C-tetrad in both DNA and RNA (thus effectively becoming a mixed quadruplex of 5 layers). The C-tetrad is stabilized by the stacking interactions with the preceding G-tetrad, by cyclical hydrogen bonds C(N4)-(O2), and by an ion between the G-tetrad and the C-tetrad. In addition, antiparallel DNA G-quadruplexes also stabilize flat C-layers at the ends of the quadruplexes.
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Affiliation(s)
- Yuan Zhang
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Christopher Roland
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Celeste Sagui
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, United States
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40
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Dickerhoff J, Weisz K. Fluorine-Mediated Editing of a G-Quadruplex Folding Pathway. Chembiochem 2018; 19:927-930. [PMID: 29460996 DOI: 10.1002/cbic.201800099] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Indexed: 12/23/2022]
Abstract
A (3+1)-hybrid-type G-quadruplex was substituted within its central tetrad by a single 2'-fluoro-modified guanosine. Driven by the anti-favoring nucleoside analogue, a novel quadruplex fold with inversion of a single G-tract and conversion of a propeller loop into a lateral loop emerges. In addition, scalar couplings across hydrogen bonds demonstrate the formation of intra- and inter-residual F⋅⋅⋅H8-C8 pseudo-hydrogen bonds within the modified quadruplexes. Alternative folding can be rationalized by the impact of fluorine on intermediate species on the basis of a kinetic partitioning mechanism. Apparently, chemical or other environmental perturbations are able to redirect folding of a quadruplex, possibly modulating its regulatory role in physiological processes.
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Affiliation(s)
- Jonathan Dickerhoff
- Institut für Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff-Strasse 4, 17487, Greifswald, Germany
| | - Klaus Weisz
- Institut für Biochemie, Ernst-Moritz-Arndt-Universität Greifswald, Felix-Hausdorff-Strasse 4, 17487, Greifswald, Germany
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41
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Zhou B, Geng Y, Liu C, Miao H, Ren Y, Xu N, Shi X, You Y, Lee T, Zhu G. Characterizations of distinct parallel and antiparallel G-quadruplexes formed by two-repeat ALS and FTD related GGGGCC sequence. Sci Rep 2018; 8:2366. [PMID: 29402965 PMCID: PMC5799222 DOI: 10.1038/s41598-018-20852-w] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/22/2018] [Indexed: 12/31/2022] Open
Abstract
The large expansion of GGGGCC (G4C2) repeats of the C9orf72 gene have been found to lead to the pathogenesis of devastating neurological diseases, amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The structural polymorphisms of C9orf72 HRE DNA and RNA may cause aberrant transcription and contribute to the development of ALS and FTD. Here we showed that the two-repeat G4C2 DNA, d(G4C2)2, simultaneously formed parallel and antiparallel G-quadruplex conformations in the potassium solution. We separated different folds of d(G4C2)2 by anion exchange chromatography, followed with characterizations by circular dichroism and nuclear magnetic resonance spectroscopy. The parallel d(G4C2)2 G-quadruplex folded as a symmetric tetramer, while the antiparallel d(G4C2)2 adopted the topology of an asymmetric dimer. These folds are distinct from the antiparallel chair-type conformation we previously identified for the d(G4C2)4 G-quadruplex. Our findings have demonstrated the conformational heterogeneity of the C9orf72 HRE DNA, and provided new insights into the d(G4C2)n folding. Meanwhile, the purified d(G4C2)2 G-quadruplex samples are suitable for further three-dimensional structure characterizations, which are required for the structure-based design of small molecules targeting ALS and FTD related C9orf72 HRE.
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Affiliation(s)
- Bo Zhou
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China. .,Institute for Advanced Study, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China.
| | - Yanyan Geng
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Changdong Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Haitao Miao
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Yaguang Ren
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Naining Xu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Xiao Shi
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Yingying You
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Tunglun Lee
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China
| | - Guang Zhu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, People's Republic of China.
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42
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Zhou CQ, Li ZQ, Liao TC, Ma TZ, Chen SB, Liang YY. A novel square-planar Pt(ii) complex as a monomeric and dimeric G-quadruplex DNA binder. RSC Adv 2018; 8:23257-23261. [PMID: 35540167 PMCID: PMC9081585 DOI: 10.1039/c8ra03606c] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/12/2018] [Indexed: 11/21/2022] Open
Abstract
A phenanthroimidazole ethylenediamine Pt(ii) complex with coumarin derivative (1) showed high binding properties and thermal stabilization for dimeric quadruplexes G2T1.
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Affiliation(s)
- Chun-Qiong Zhou
- Guangdong Provincial Key Laboratory of New Drug Screening
- School of Pharmaceutical Sciences
- Southern Medical University
- Guangzhou 510515
- China
| | - Zi-Qi Li
- Guangdong Provincial Key Laboratory of New Drug Screening
- School of Pharmaceutical Sciences
- Southern Medical University
- Guangzhou 510515
- China
| | - Ting-Cong Liao
- Guangdong Provincial Key Laboratory of New Drug Screening
- School of Pharmaceutical Sciences
- Southern Medical University
- Guangzhou 510515
- China
| | - Tian-Zhu Ma
- Guangdong Provincial Key Laboratory of New Drug Screening
- School of Pharmaceutical Sciences
- Southern Medical University
- Guangzhou 510515
- China
| | - Shuo-Bin Chen
- School of Pharmaceutical Sciences
- Sun Yat-sen University
- Guangzhou 51006
- China
| | - Yuan-Yuan Liang
- Guangdong Provincial Key Laboratory of New Drug Screening
- School of Pharmaceutical Sciences
- Southern Medical University
- Guangzhou 510515
- China
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43
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Telomeric G-Quadruplexes: From Human to Tetrahymena Repeats. J Nucleic Acids 2017; 2017:9170371. [PMID: 29445544 PMCID: PMC5763100 DOI: 10.1155/2017/9170371] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 11/11/2017] [Accepted: 12/05/2017] [Indexed: 11/26/2022] Open
Abstract
The human telomeric and protozoal telomeric sequences differ only in one purine base in their repeats; TTAGGG in telomeric sequences; and TTGGGG in protozoal sequences. In this study, the relationship between G-quadruplexes formed from these repeats and their derivatives is analyzed and compared. The human telomeric DNA sequence G3(T2AG3)3 and related sequences in which each adenine base has been systematically replaced by a guanine were investigated; the result is Tetrahymena repeats. The substitution does not affect the formation of G-quadruplexes but may cause differences in topology. The results also show that the stability of the substituted derivatives increased in sequences with greater number of substitutions. In addition, most of the sequences containing imperfections in repeats which were analyzed in this study also occur in human and Tetrahymena genomes. Generally, the presence of G-quadruplex structures in any organism is a source of limitations during the life cycle. Therefore, a fuller understanding of the influence of base substitution on the structural variability of G-quadruplexes would be of considerable scientific value.
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44
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Dickerhoff J, Weisz K. Nonconventional C-H···F Hydrogen Bonds Support a Tetrad Flip in Modified G-Quadruplexes. J Phys Chem Lett 2017; 8:5148-5152. [PMID: 28976755 DOI: 10.1021/acs.jpclett.7b02428] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A G-quadruplex adopting a (3 + 1)-hybrid structure was substituted at its 5'-tetrad by 2'-deoxy-2'-fluoro-arabinoguanosine (FaraG) analogs. Incorporation of anti-favoring FaraG at syn-positions of the 5'-outer tetrad induced a reversal of the tetrad polarity without noticeably compromising the quadruplex stability. This conformational change is shown to be promoted by nonconventional C-H···F hydrogen bonds acting within the anti-FaraG residues.
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Affiliation(s)
- Jonathan Dickerhoff
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Str. 4, D-17487 Greifswald, Germany
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45
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Sagi J. In What Ways Do Synthetic Nucleotides and Natural Base Lesions Alter the Structural Stability of G-Quadruplex Nucleic Acids? J Nucleic Acids 2017; 2017:1641845. [PMID: 29181193 PMCID: PMC5664352 DOI: 10.1155/2017/1641845] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 08/15/2017] [Indexed: 01/03/2023] Open
Abstract
Synthetic analogs of natural nucleotides have long been utilized for structural studies of canonical and noncanonical nucleic acids, including the extensively investigated polymorphic G-quadruplexes (GQs). Dependence on the sequence and nucleotide modifications of the folding landscape of GQs has been reviewed by several recent studies. Here, an overview is compiled on the thermodynamic stability of the modified GQ folds and on how the stereochemical preferences of more than 70 synthetic and natural derivatives of nucleotides substituting for natural ones determine the stability as well as the conformation. Groups of nucleotide analogs only stabilize or only destabilize the GQ, while the majority of analogs alter the GQ stability in both ways. This depends on the preferred syn or anti N-glycosidic linkage of the modified building blocks, the position of substitution, and the folding architecture of the native GQ. Natural base lesions and epigenetic modifications of GQs explored so far also stabilize or destabilize the GQ assemblies. Learning the effect of synthetic nucleotide analogs on the stability of GQs can assist in engineering a required stable GQ topology, and exploring the in vitro action of the single and clustered natural base damage on GQ architectures may provide indications for the cellular events.
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Affiliation(s)
- Janos Sagi
- Rimstone Laboratory, RLI, Carlsbad, CA 92010, USA
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46
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Antiparallel RNA G-quadruplex Formed by Human Telomere RNA Containing 8-Bromoguanosine. Sci Rep 2017; 7:6695. [PMID: 28751647 PMCID: PMC5532209 DOI: 10.1038/s41598-017-07050-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/21/2017] [Indexed: 11/09/2022] Open
Abstract
In this study, by combining nuclear magnetic resonance (NMR), circular dichroism (CD), liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS), and gel electrophoresis, we report an unusual topological structure of the RNA G-quadruplex motif formed by human telomere RNA r(UAGGGU) containing 8-bromoguanosine. Results showed that the RNA sequence formed an antiparallel tetramolecular G-quadruplex, in which each pair of diagonal strands run in opposite directions. Furthermore, guanosines were observed both in syn- and anti-conformations. In addition, two of these G-quadruplex subunits were found to be stacking on top of each other, forming a dimeric RNA G-quadruplex. Our findings provide a new insight into the behavior of RNA G-quadruplex structures.
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47
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48
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Zhou CQ, Liao TC, Li ZQ, Gonzalez-Garcia J, Reynolds M, Zou M, Vilar R. Dinickel-Salphen Complexes as Binders of Human Telomeric Dimeric G-Quadruplexes. Chemistry 2017; 23:4713-4722. [PMID: 28207952 PMCID: PMC5516229 DOI: 10.1002/chem.201700276] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Indexed: 12/12/2022]
Abstract
Three new polyether‐tethered dinickel–salphen complexes (2 a–c) have been synthesized and fully characterized by NMR spectroscopy, mass spectrometry, and elemental analyses. The binding affinity and selectivity of these complexes and of the parent mono‐nickel complex (1) towards dimeric quadruplex DNA have been determined by UV/Vis titrations, fluorescence spectroscopy, CD spectroscopy, and electrophoresis. These studies have shown that the dinickel–salphen complex with the longest polyether linker (2 c) has higher binding affinity and selectivity towards dimeric quadruplexes (over monomeric quadruplexes) than the dinickel–salphen complexes with the shorter polyether linkers (2 a and 2 b). Complex 2 c also has higher selectivity towards human telomeric dimeric quadruplexes with one TTA linker than the monometallic complex 1. Based on the spectroscopic data, a possible binding mode between complex 2 c and the dimeric G‐quadruplex DNA under study is proposed.
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Affiliation(s)
- Chun-Qiong Zhou
- Department of Chemistry, Imperial College London, South Kensington, London, SW72AZ, UK.,Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, P. R. China
| | - Ting-Cong Liao
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, P. R. China
| | - Zi-Qi Li
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, P. R. China
| | - Jorge Gonzalez-Garcia
- Department of Chemistry, Imperial College London, South Kensington, London, SW72AZ, UK
| | - Matthew Reynolds
- Department of Chemistry, Imperial College London, South Kensington, London, SW72AZ, UK
| | - Min Zou
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou, 510515, P. R. China
| | - Ramon Vilar
- Department of Chemistry, Imperial College London, South Kensington, London, SW72AZ, UK
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49
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Li ZQ, Liao TC, Dong C, Yang JW, Chen XJ, Liu L, Luo Y, Liang YY, Chen WH, Zhou CQ. Specifically targeting mixed-type dimeric G-quadruplexes using berberine dimers. Org Biomol Chem 2017; 15:10221-10229. [DOI: 10.1039/c7ob02326j] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Berberine dimer (1a) with the shortest polyether linker demonstrates highest binding affinity, selectivity and thermal stabilization towards mixed-type dimeric quadruplexes.
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Karg B, Haase L, Funke A, Dickerhoff J, Weisz K. Observation of a Dynamic G-Tetrad Flip in Intramolecular G-Quadruplexes. Biochemistry 2016; 55:6949-6955. [PMID: 27951645 DOI: 10.1021/acs.biochem.6b00925] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A MYC sequence forming an intramolecular G-quadruplex with a parallel topology was modified by the incorporation of 8-bromoguanosine (BrG) analogues in one of its outer G-tetrads. The propensity of the BrG analogues to adopt a syn glycosidic torsion angle results in an exceptional monomolecular quadruplex conformation featuring a complete flip of one tetrad while keeping a parallel orientation of all G-tracts as shown by circular dichroism and nuclear magnetic resonance spectroscopic studies. When substituting three of the four G-tetrad residues with BrG analogues, two coexisting quadruplex conformational isomers with an all-syn and all-anti outer G-quartet are approximately equally populated in solution. A dynamic interconversion of the two quadruplexes with an exchange rate (kex) of 0.2 s-1 is demonstrated through the observation of exchange crosspeaks in rotating frame Overhauser effect spectroscopy and nuclear Overhauser effect spectroscopy experiments at 50 °C. The kinetic properties suggest disruption of the corresponding outer G-tetrad but not of the whole quadruplex core during the tetrad flip. Conformational syn-anti isomers with homopolar and heteropolar stacking interactions are nearly isoenergetic with a transition enthalpy of 18.2 kJ/mol in favor of the all-syn isomer.
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Affiliation(s)
- Beatrice Karg
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Linn Haase
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Andrea Funke
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Jonathan Dickerhoff
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
| | - Klaus Weisz
- Institute of Biochemistry, Ernst-Moritz-Arndt University Greifswald , Felix-Hausdorff-Strasse 4, D-17487 Greifswald, Germany
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