1
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Tao S, Run Y, Monchaud D, Zhang W. i-Motif DNA: identification, formation, and cellular functions. Trends Genet 2024:S0168-9525(24)00133-1. [PMID: 38902139 DOI: 10.1016/j.tig.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/29/2024] [Accepted: 05/29/2024] [Indexed: 06/22/2024]
Abstract
An i-motif (iM) is a four-stranded (quadruplex) DNA structure that folds from cytosine (C)-rich sequences. iMs can fold under many different conditions in vitro, which paves the way for their formation in living cells. iMs are thought to play key roles in various DNA transactions, notably in the regulation of genome stability, gene transcription, mRNA translation, DNA replication, telomere and centromere functions, and human diseases. We summarize the different techniques used to assess the folding of iMs in vitro and provide an overview of the internal and external factors that affect their formation and stability in vivo. We describe the possible biological relevance of iMs and propose directions towards their use as target in biology.
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Affiliation(s)
- Shentong Tao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production (CIC-MCP), Nanjing Agricultural University, 1 Weigang, Nanjing, Jiangsu 210095, China
| | - Yonghang Run
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production (CIC-MCP), Nanjing Agricultural University, 1 Weigang, Nanjing, Jiangsu 210095, China
| | - David Monchaud
- Institut de Chimie Moleculaire de l'Université de Bourgogne (ICMUB), Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 6302, Université Bourgogne Franche Comté (UBFC), Dijon, France
| | - Wenli Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, Collaborative Innovation Center for Modern Crop Production (CIC-MCP), Nanjing Agricultural University, 1 Weigang, Nanjing, Jiangsu 210095, China.
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2
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Mir B, Serrano-Chacón I, Medina P, Macaluso V, Terrazas M, Gandioso A, Garavís M, Orozco M, Escaja N, González C. Site-specific incorporation of a fluorescent nucleobase analog enhances i-motif stability and allows monitoring of i-motif folding inside cells. Nucleic Acids Res 2024; 52:3375-3389. [PMID: 38366792 PMCID: PMC11014255 DOI: 10.1093/nar/gkae106] [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: 04/28/2023] [Revised: 01/17/2024] [Accepted: 02/09/2024] [Indexed: 02/18/2024] Open
Abstract
The i-motif is an intriguing non-canonical DNA structure, whose role in the cell is still controversial. Development of methods to study i-motif formation under physiological conditions in living cells is necessary to study its potential biological functions. The cytosine analog 1,3-diaza-2-oxophenoxazine (tCO) is a fluorescent nucleobase able to form either hemiprotonated base pairs with cytosine residues, or neutral base pairs with guanines. We show here that when tCO is incorporated in the proximity of a G:C:G:C minor groove tetrad, it induces a strong thermal and pH stabilization, resulting in i-motifs with Tm of 39ºC at neutral pH. The structural determination by NMR methods reveals that the enhanced stability is due to a large stacking interaction between the guanines of the tetrad with the tCO nucleobase, which forms a tCO:C+ in the folded structure at unusually-high pHs, leading to an increased quenching in its fluorescence at neutral conditions. This quenching is much lower when tCO is base-paired to guanines and totally disappears when the oligonucleotide is unfolded. By taking profit of this property, we have been able to monitor i-motif folding in cells.
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Affiliation(s)
- Bartomeu Mir
- Instituto de Química Física ‘Blas Cabrera’. CSIC. Serrano 119. 28006 Madrid. Spain
- Inorganic and Organic Chemistry Department. Organic Chemistry Section and IBUB. University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona. Spain
| | - Israel Serrano-Chacón
- Instituto de Química Física ‘Blas Cabrera’. CSIC. Serrano 119. 28006 Madrid. Spain
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
| | - Pedro Medina
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
- Departament de Bioquímica i Biomedicina. Facultat de Biologia. Universitat de Barcelona. 08028 Barcelona. Spain
| | - Veronica Macaluso
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
| | - Montserrat Terrazas
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
- Inorganic and Organic Chemistry Department. Organic Chemistry Section and IBUB. University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona. Spain
| | - Albert Gandioso
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
| | - Miguel Garavís
- Instituto de Química Física ‘Blas Cabrera’. CSIC. Serrano 119. 28006 Madrid. Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona). The Barcelona Institute of Science and Technology (BIST). 08028 Barcelona. Spain
- Departament de Bioquímica i Biomedicina. Facultat de Biologia. Universitat de Barcelona. 08028 Barcelona. Spain
| | - Núria Escaja
- Inorganic and Organic Chemistry Department. Organic Chemistry Section and IBUB. University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona. Spain
| | - Carlos González
- Instituto de Química Física ‘Blas Cabrera’. CSIC. Serrano 119. 28006 Madrid. Spain
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3
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Yang B, Guneri D, Yu H, Wright EP, Chen W, Waller ZE, Ding Y. Prediction of DNA i-motifs via machine learning. Nucleic Acids Res 2024; 52:2188-2197. [PMID: 38364855 PMCID: PMC10954440 DOI: 10.1093/nar/gkae092] [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: 12/06/2023] [Revised: 01/24/2024] [Accepted: 01/29/2024] [Indexed: 02/18/2024] Open
Abstract
i-Motifs (iMs), are secondary structures formed in cytosine-rich DNA sequences and are involved in multiple functions in the genome. Although putative iM forming sequences are widely distributed in the human genome, the folding status and strength of putative iMs vary dramatically. Much previous research on iM has focused on assessing the iM folding properties using biophysical experiments. However, there are no dedicated computational tools for predicting the folding status and strength of iM structures. Here, we introduce a machine learning pipeline, iM-Seeker, to predict both folding status and structural stability of DNA iMs. The programme iM-Seeker incorporates a Balanced Random Forest classifier trained on genome-wide iMab antibody-based CUT&Tag sequencing data to predict the folding status and an Extreme Gradient Boosting regressor to estimate the folding strength according to both literature biophysical data and our in-house biophysical experiments. iM-Seeker predicts DNA iM folding status with a classification accuracy of 81% and estimates the folding strength with coefficient of determination (R2) of 0.642 on the test set. Model interpretation confirms that the nucleotide composition of the C-rich sequence significantly affects iM stability, with a positive correlation with sequences containing cytosine and thymine and a negative correlation with guanine and adenine.
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Affiliation(s)
- Bibo Yang
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Dilek Guneri
- School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Haopeng Yu
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
| | - Elisé P Wright
- Molecular Physiology School of Medicine, and Molecular Medicine Research Group, University of Western Sydney, Campbelltown, NSW 1797, Australia
| | - Wenqian Chen
- School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Zoë A E Waller
- School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Yiliang Ding
- Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Norwich NR4 7UH, UK
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4
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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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5
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Feng Y, Ma X, Yang Y, Tao S, Ahmed A, Gong Z, Cheng X, Zhang W. The roles of DNA methylation on pH dependent i-motif (iM) formation in rice. Nucleic Acids Res 2024; 52:1243-1257. [PMID: 38180820 PMCID: PMC10853798 DOI: 10.1093/nar/gkad1245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 12/14/2023] [Accepted: 12/19/2023] [Indexed: 01/07/2024] Open
Abstract
I-motifs (iMs) are four-stranded non-B DNA structures containing C-rich DNA sequences. The formation of iMs is sensitive to pH conditions and DNA methylation, although the extent of which is still unknown in both humans and plants. To investigate this, we here conducted iMab antibody-based immunoprecipitation and sequencing (iM-IP-seq) along with bisulfite sequencing using CK (original genomic DNA without methylation-related treatments) and hypermethylated or demethylated DNA at both pH 5.5 and 7.0 in rice, establishing a link between pH, DNA methylation and iM formation on a genome-wide scale. We found that iMs folded at pH 7.0 displayed higher methylation levels than those formed at pH 5.5. DNA demethylation and hypermethylation differently influenced iM formation at pH 7.0 and 5.5. Importantly, CG hypo-DMRs (differentially methylated regions) and CHH (H = A, C and T) hyper-DMRs alone or coordinated with CG/CHG hyper-DMRs may play determinant roles in the regulation of pH dependent iM formation. Thus, our study shows that the nature of DNA sequences alone or combined with their methylation status plays critical roles in determining pH-dependent formation of iMs. It therefore deepens the understanding of the pH and methylation dependent modulation of iM formation, which has important biological implications and practical applications.
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Affiliation(s)
- Yilong Feng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Xing Ma
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Ying Yang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Shentong Tao
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Asgar Ahmed
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
- Bangladesh Wheat and Maize Research Institute (BWMRI), Nashipur, Dinajpur 5200, Bangladesh
| | - Zhiyun Gong
- Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding, Agricultural College of Yangzhou University, Yangzhou 225009, China
| | - Xuejiao Cheng
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
| | - Wenli Zhang
- State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization, CIC-MCP, Nanjing Agricultural University, No.1 Weigang, Nanjing, Jiangsu 210095, China
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6
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Smirnov E, Molínová P, Chmúrčiaková N, Vacík T, Cmarko D. Non-canonical DNA structures in the human ribosomal DNA. Histochem Cell Biol 2023; 160:499-515. [PMID: 37750997 DOI: 10.1007/s00418-023-02233-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2023] [Indexed: 09/27/2023]
Abstract
Non-canonical structures (NCS) refer to the various forms of DNA that differ from the B-conformation described by Watson and Crick. It has been found that these structures are usual components of the genome, actively participating in its essential functions. The present review is focused on the nine kinds of NCS appearing or likely to appear in human ribosomal DNA (rDNA): supercoiling structures, R-loops, G-quadruplexes, i-motifs, DNA triplexes, cruciform structures, DNA bubbles, and A and Z DNA conformations. We discuss the conditions of their generation, including their sequence specificity, distribution within the locus, dynamics, and beneficial and detrimental role in the cell.
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Affiliation(s)
- Evgeny Smirnov
- Laboratory of Cell Biology, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, 128 00, Prague, Czech Republic.
| | - Pavla Molínová
- Laboratory of Cell Biology, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, 128 00, Prague, Czech Republic
| | - Nikola Chmúrčiaková
- Laboratory of Cell Biology, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, 128 00, Prague, Czech Republic
| | - Tomáš Vacík
- Laboratory of Cell Biology, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, 128 00, Prague, Czech Republic
| | - Dušan Cmarko
- Laboratory of Cell Biology, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University and General University Hospital in Prague, 128 00, Prague, Czech Republic
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7
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Ghezzo M, Trajkovski M, Plavec J, Sissi C. A Screening Protocol for Exploring Loop Length Requirements for the Formation of a Three Cytosine-Cytosine + Base-Paired i-Motif. Angew Chem Int Ed Engl 2023; 62:e202309327. [PMID: 37611164 DOI: 10.1002/anie.202309327] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/21/2023] [Accepted: 08/23/2023] [Indexed: 08/25/2023]
Abstract
DNA sequences containing at least four runs of repetitive cytosines can fold into tetra-helical structures called i-Motifs (iMs). The interest in these DNA secondary structures is increasing due to their therapeutical and technological applications. Still, limited knowledge of their folding requirements is currently available. We developed a novel step-by-step pipeline for the systematic screening of putative iM-forming model sequences. Focusing on structures comprising only three cytosine-cytosine+ base pairs, we investigated what the minimal lengths of the loops required for formation of an intra-molecular iM are. Our data indicate that two and three nucleotides are required to connect the strands through the minor and majorgrooves of the iM, respectively. Additionally, they highlight an asymmetric behavior according to the distribution of the cytosines. Specifically, no sequence containing a single cytosine in the first and third run was able to fold into intra-molecular iMs with the same stability of those formed when the first and the third run comprise two cytosines. This knowledge represents a step forward toward the development of prediction tools for the proper identification of biologically functional iMs, as well as for the rational design of these secondary structures as technological devices.
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Affiliation(s)
- Michele Ghezzo
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
| | - Marko Trajkovski
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Janez Plavec
- Slovenian NMR Centre, National Institute of Chemistry, Hajdrihova 19, 1000, Ljubljana, Slovenia
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Science, University of Padua, Via Marzolo 5, 35131, Padua, Italy
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8
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Improta R. Shedding Light on the Photophysics and Photochemistry of I-Motifs Using Quantum Mechanical Calculations. Int J Mol Sci 2023; 24:12614. [PMID: 37628797 PMCID: PMC10454157 DOI: 10.3390/ijms241612614] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 08/07/2023] [Indexed: 08/27/2023] Open
Abstract
I-motifs are non-canonical DNA structures formed by intercalated hemiprotonated (CH·C)+ pairs, i.e., formed by a cytosine (C) and a protonated cytosine (CH+), which are currently drawing great attention due to their biological relevance and promising nanotechnological properties. It is important to characterize the processes occurring in I-motifs following irradiation by UV light because they can lead to harmful consequences for genetic code and because optical spectroscopies are the most-used tools to characterize I-motifs. By using time-dependent DFT calculations, we here provide the first comprehensive picture of the photoactivated behavior of the (CH·C)+ core of I-motifs, from absorption to emission, while also considering the possible photochemical reactions. We reproduce and assign their spectral signatures, i.e., infrared, absorption, fluorescence and circular dichroism spectra, disentangling the underlying chemical-physical effects. We show that the main photophysical paths involve C and CH+ bases on adjacent steps and, using this basis, interpret the available time-resolved spectra. We propose that a photodimerization reaction can occur on an excited state with strong C→CH+ charge transfer character and examine some of the possible photoproducts. Based on the results reported, some future perspectives for the study of I-motifs are discussed.
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Affiliation(s)
- Roberto Improta
- Consiglio Nazionale delle Ricerche, Istituto di Biostrutture e Bioimmagini (IBB-CNR), Via De Amicis 95, I-80145 Napoli, Italy
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9
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Li KS, Jordan D, Lin LY, McCarthy SE, Schneekloth JS, Yatsunyk LA. Crystal Structure of an i-Motif from the HRAS Oncogene Promoter. Angew Chem Int Ed Engl 2023; 62:e202301666. [PMID: 36995904 PMCID: PMC10330059 DOI: 10.1002/anie.202301666] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/22/2023] [Accepted: 03/28/2023] [Indexed: 03/31/2023]
Abstract
An i-motif is a non-canonical DNA structure implicated in gene regulation and linked to cancers. The C-rich strand of the HRAS oncogene, 5'-CGCCCGTGCCCTGCGCCCGCAACCCGA-3' (herein referred to as iHRAS), forms an i-motif in vitro but its exact structure was unknown. HRAS is a member of the RAS proto-oncogene family. About 19 % of US cancer patients carry mutations in RAS genes. We solved the structure of iHRAS at 1.77 Å resolution. The structure reveals that iHRAS folds into a double hairpin. The two double hairpins associate in an antiparallel fashion, forming an i-motif dimer capped by two loops on each end and linked by a connecting region. Six C-C+ base pairs form each i-motif core, and the core regions are extended by a G-G base pair and a cytosine stacking. Extensive canonical and non-canonical base pairing and stacking stabilizes the connecting region and loops. The iHRAS structure is the first atomic resolution structure of an i-motif from a human oncogene. This structure sheds light on i-motifs folding and function in the cell.
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Affiliation(s)
- Kevin S Li
- Department Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Deondre Jordan
- Department Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Linda Y Lin
- Department Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - Sawyer E McCarthy
- Department Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
| | - John S Schneekloth
- Chemical Biology Laboratory, National Cancer Institute, National Institute of Health, Frederick, MD 21702, USA
| | - Liliya A Yatsunyk
- Department Chemistry and Biochemistry, Swarthmore College, 500 College Ave, Swarthmore, PA 19081, USA
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10
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Rodriguez J, Domínguez A, Aviñó A, Borgonovo G, Eritja R, Mazzini S, Gargallo R. Exploring the stabilizing effect on the i-motif of neighboring structural motifs and drugs. Int J Biol Macromol 2023; 242:124794. [PMID: 37182626 DOI: 10.1016/j.ijbiomac.2023.124794] [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: 03/13/2023] [Revised: 04/18/2023] [Accepted: 04/25/2023] [Indexed: 05/16/2023]
Abstract
Cytosine-rich DNA sequences may fold into a structure known as i-motif, with potential in vivo modulation of gene expression. The stability of the i-motif is residual at neutral pH values. To increase it, the addition of neighboring moieties, such as Watson-Crick stabilized loops, tetrads, or non-canonical base pairs have been proposed. Taking a recently described i-motif structure as a model, the relative effect of these structural moieties, as well as several DNA ligands, on the stabilization of the i-motif has been studied. To this end, not only the original sequence but different mutants were considered. Spectroscopic techniques, PAGE, and multivariate data analysis methods have been used to model the folding/unfolding equilibria induced by changes of pH, temperature, and the presence of ligands. The results have shown that the duplex is the moiety that is responsible of the stabilization of the i-motif structure at neutral pH. The T:T base pair, on the contrary, shows little stabilization of the i-motif. From several selected DNA-binding ligands, the G-quadruplex ligand BA41 is shown to interact with the duplex moiety, whereas non-specific interaction and little stabilization has been observed within the i-motif.
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Affiliation(s)
- Judit Rodriguez
- Department of Chemical Engineering and Analytical Chemistry, Faculty of Chemistry, University of Barcelona, Marti i Franqués 1-11, E-08028 Barcelona, Spain
| | - Arnau Domínguez
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Anna Aviñó
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Gigliola Borgonovo
- Department of Food, Environmental and Nutritional Sciences (DEFENS), University of Milan (Università degli Studi di Milano), Milan, Italy
| | - Ramon Eritja
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Stefania Mazzini
- Department of Food, Environmental and Nutritional Sciences (DEFENS), University of Milan (Università degli Studi di Milano), Milan, Italy
| | - Raimundo Gargallo
- Department of Chemical Engineering and Analytical Chemistry, Faculty of Chemistry, University of Barcelona, Marti i Franqués 1-11, E-08028 Barcelona, Spain.
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11
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Zhang L, Tan QG, Xiao SJ, Yang GP, Zheng QQ, Sun C, Mao XL, Fan JQ, Liang RP, Qiu JD. Reversed Regulation Effects of ssDNA on the Mimetic Oxidase and Peroxidase Activities of Covalent Organic Frameworks. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2207798. [PMID: 37012604 DOI: 10.1002/smll.202207798] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 03/13/2023] [Indexed: 06/19/2023]
Abstract
Nanomaterials with enzyme mimetic activity have attracted extensive attention, especially in the regulation of their catalytic activities by biomolecules or other polymers. Here, a covalent organic framework (Tph-BT COF) with excellent photocatalytic activity is constructed by Schiff base reaction, and its mimetic oxidase activity and peroxidase activity is inversely regulated via single-stranded DNA (ssDNA). Under light-emitting diode (LED) light irradiation, Tph-BT exhibited outstanding oxidase activity, which efficiently catalyzed oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce blue oxTMB, and ssDNA, especially those with poly-thymidine (T) sequences, can significantly inhibit its oxidase activity. On the contrary, Tph-BT showed weak peroxidase activity, and the presence of ssDNA, particularly poly-cytosine (C) sequences, can remarkably enhance the peroxidase activity. The influence of base type, base length, and other factors on the activities of two enzymes is also studied, and the results reveal that the adsorption of ssDNA on the surface of Tph-BT prevented intersystem crossing (ISC) and energy transfer processes to reduce 1 O2 generation, while the electrostatic interaction between ssDNA and TMB enhanced Tph-BT's affinity for TMB to facilitate the electron transfer from TMB to • OH. This study investigates multitype mimetic enzyme activities of nonmetallic D-A conjugated COFs and demonstrates their feasibility of regulation by ssDNA.
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Affiliation(s)
- Li Zhang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Quan-Gen Tan
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Sai-Jin Xiao
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology (ECUT), Nanchang, 330013, P. R. China
| | - Gui-Ping Yang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Qiong-Qing Zheng
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Chen Sun
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Xiang-Lan Mao
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Jia-Qi Fan
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Ru-Ping Liang
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
| | - Jian-Ding Qiu
- School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, P. R. China
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology (ECUT), Nanchang, 330013, P. R. China
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12
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Luo X, Zhang J, Gao Y, Pan W, Yang Y, Li X, Chen L, Wang C, Wang Y. Emerging roles of i-motif in gene expression and disease treatment. Front Pharmacol 2023; 14:1136251. [PMID: 37021044 PMCID: PMC10067743 DOI: 10.3389/fphar.2023.1136251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Accepted: 02/27/2023] [Indexed: 03/22/2023] Open
Abstract
As non-canonical nucleic acid secondary structures consisting of cytosine-rich nucleic acids, i-motifs can form under certain conditions. Several i-motif sequences have been identified in the human genome and play important roles in biological regulatory functions. Due to their physicochemical properties, these i-motif structures have attracted attention and are new targets for drug development. Herein, we reviewed the characteristics and mechanisms of i-motifs located in gene promoters (including c-myc, Bcl-2, VEGF, and telomeres), summarized various small molecule ligands that interact with them, and the possible binding modes between ligands and i-motifs, and described their effects on gene expression. Furthermore, we discussed diseases closely associated with i-motifs. Among these, cancer is closely associated with i-motifs since i-motifs can form in some regions of most oncogenes. Finally, we introduced recent advances in the applications of i-motifs in multiple areas.
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Affiliation(s)
| | | | | | | | | | | | | | - Chang Wang
- *Correspondence: Chang Wang, ; Yuqing Wang,
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13
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Petrunina NA, Shtork AS, Lukina MM, Tsvetkov VB, Khodarovich YM, Feofanov AV, Moysenovich AM, Maksimov EG, Shipunova VO, Zatsepin TS, Bogomazova AN, Shender VO, Aralov AV, Lagarkova MA, Varizhuk AM. Ratiometric i-Motif-Based Sensor for Precise Long-Term Monitoring of pH Micro Alterations in the Nucleoplasm and Interchromatin Granules. ACS Sens 2023; 8:619-629. [PMID: 36662613 DOI: 10.1021/acssensors.2c01813] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
DNA-intercalated motifs (iMs) are facile scaffolds for the design of various pH-responsive nanomachines, including biocompatible pH sensors. First, DNA pH sensors relied on complex intermolecular scaffolds. Here, we used a simple unimolecular dual-labeled iM scaffold and minimized it by replacing the redundant loop nucleosides with abasic or alkyl linkers. These modifications improved the thermal stability of the iM and increased the rates of its pH-induced conformational transitions. The best effects were obtained upon the replacement of all three native loops with short and flexible linkers, such as the propyl one. The resulting sensor showed a pH transition value equal to 6.9 ± 0.1 and responded rapidly to minor acidification (tau1/2 <1 s for 7.2 → 6.6 pH jump). We demonstrated the applicability of this sensor for pH measurements in the nuclei of human lung adenocarcinoma cells (pH = 7.4 ± 0.2) and immortalized embryonic kidney cells (pH = 7.0 ± 0.2). The sensor stained diffusely the nucleoplasm and piled up in interchromatin granules. These findings highlight the prospects of iMs in the studies of normal and pathological pH-dependent processes in the nucleus, including the formation of biomolecular condensates.
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Affiliation(s)
- Nataliia A Petrunina
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia
| | - Alina S Shtork
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia
| | - Maria M Lukina
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow119435, Russia
| | - Vladimir B Tsvetkov
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Institute of Biodesign and Complex System Modeling, I.M. Sechenov First Moscow State Medical University, Moscow119991, Russia.,A.V. Topchiev Institute of Petrochemical Synthesis RAS, Leninsky Prospect Str. 29, Moscow119991, Russia
| | - Yuri M Khodarovich
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow117997, Russia.,The Peoples' Friendship University of Russia, 117198Moscow, Russia
| | - Alexey V Feofanov
- Biological Faculty, Lomonosov Moscow State University, Moscow119992, Russia.,Institute of Gene Biology RAS, Russian Academy of Sciences, Moscow119334, Russia
| | | | - Eugene G Maksimov
- Biological Faculty, Lomonosov Moscow State University, Moscow119992, Russia
| | - Victoria O Shipunova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow117997, Russia
| | - Timofei S Zatsepin
- Department of Chemistry, Lomonosov Moscow State University, Moscow119992, Russia
| | - Alexandra N Bogomazova
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow119435, Russia
| | - Victoria O Shender
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow119435, Russia.,Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow117997, Russia
| | - Andrey V Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow117997, Russia
| | - Maria A Lagarkova
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow119435, Russia
| | - Anna M Varizhuk
- Federal Research and Clinical Center of Physical-Chemical Medicine, Moscow119435, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow119435, Russia.,G4_Interact, USERN, University of Pavia, 27100Pavia, Italy
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14
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Serrano-Chacón I, Mir B, Cupellini L, Colizzi F, Orozco M, Escaja N, González C. pH-Dependent Capping Interactions Induce Large-Scale Structural Transitions in i-Motifs. J Am Chem Soc 2023; 145:3696-3705. [PMID: 36745195 PMCID: PMC9936585 DOI: 10.1021/jacs.2c13043] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Indexed: 02/07/2023]
Abstract
We study here a DNA oligonucleotide having the ability to form two different i-motif structures whose relative stability depends on pH and temperature. The major species at neutral pH is stabilized by two C:C+ base pairs capped by two minor groove G:C:G:C tetrads. The high pH and thermal stability of this structure are mainly due to the favorable effect of the minor groove tetrads on their adjacent positively charged C:C+ base pairs. At pH 5, we observe a more elongated i-motif structure consisting of four C:C+ base pairs capped by two G:T:G:T tetrads. Molecular dynamics calculations show that the conformational transition between the two structures is driven by the protonation state of key cytosines. In spite of large conformational differences, the transition between the acidic and neutral structures can occur without unfolding of the i-motif. These results represent the first case of a conformational switch between two different i-motif structures and illustrate the dramatic pH-dependent plasticity of this fascinating DNA motif.
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Affiliation(s)
- Israel Serrano-Chacón
- Instituto
de Química Física ”Rocasolano”, CSIC, Serrano 119, 28006Madrid, Spain
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028Barcelona, Spain
| | - Bartomeu Mir
- Instituto
de Química Física ”Rocasolano”, CSIC, Serrano 119, 28006Madrid, Spain
- Inorganic
and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028Barcelona, Spain
| | - Lorenzo Cupellini
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028Barcelona, Spain
| | - Francesco Colizzi
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028Barcelona, Spain
| | - Modesto Orozco
- Institute
for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), 08028Barcelona, Spain
- Departament
de Bioquímica i Biomedicina. Facultat de Biologia, Universitat de Barcelona, 08028Barcelona, Spain
| | - Núria Escaja
- Inorganic
and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028Barcelona, Spain
- BIOESTRAN
Associated Unit UB-CSIC, 08028Barcelona, Spain
| | - Carlos González
- Instituto
de Química Física ”Rocasolano”, CSIC, Serrano 119, 28006Madrid, Spain
- BIOESTRAN
Associated Unit UB-CSIC, 08028Barcelona, Spain
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15
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Escaja N, Mir B, Garavís M, González C. Non-G Base Tetrads. Molecules 2022; 27:5287. [PMID: 36014524 PMCID: PMC9414646 DOI: 10.3390/molecules27165287] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 08/03/2022] [Accepted: 08/11/2022] [Indexed: 11/17/2022] Open
Abstract
Tetrads (or quartets) are arrangements of four nucleobases commonly involved in the stability of four-stranded nucleic acids structures. Four-stranded or quadruplex structures have attracted enormous attention in the last few years, being the most extensively studied guanine quadruplex (G-quadruplex). Consequently, the G-tetrad is the most common and well-known tetrad. However, this is not the only possible arrangement of four nucleobases. A number of tetrads formed by the different nucleobases have been observed in experimental structures. In most cases, these tetrads occur in the context of G-quadruplex structures, either inserted between G-quartets, or as capping elements at the sides of the G-quadruplex core. In other cases, however, non-G tetrads are found in more unusual four stranded structures, such as i-motifs, or different types of peculiar fold-back structures. In this report, we review the diversity of these non-canonical tetrads, and the structural context in which they have been found.
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Affiliation(s)
- Núria Escaja
- Organic Chemistry Section, Inorganic and Organic Chemistry Department, University of Barcelona, Martí i Franquès 1–11, 08028 Barcelona, Spain
- Institute of Biomedicine, University of Barcelona, Av. Diagonal 645, 08028 Barcelona, Spain
| | - Bartomeu Mir
- Organic Chemistry Section, Inorganic and Organic Chemistry Department, University of Barcelona, Martí i Franquès 1–11, 08028 Barcelona, Spain
- Institute of Biomedicine, University of Barcelona, Av. Diagonal 645, 08028 Barcelona, Spain
| | - Miguel Garavís
- Instituto de Química Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
| | - Carlos González
- Instituto de Química Física ‘Rocasolano’, CSIC, Serrano 119, 28006 Madrid, Spain
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16
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Mondal M, Gao YQ. Microscopic Insight into pH-Dependent Conformational Dynamics and Noncanonical Base Pairing in Telomeric i-Motif DNA. J Phys Chem Lett 2022; 13:5109-5115. [PMID: 35657602 DOI: 10.1021/acs.jpclett.2c00640] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Gene regulatory functions of noncanonical i-motif DNA are associated with dynamic i-motif formation in the cellular environment and pH variation. With atomistic simulations, we show the dramatic influence of solvent pH on the conformational dynamics of biologically relevant telomeric i-motif DNA coupled with protonation of cytosine bases in different conformations. We rationalized the pH-dependent dynamics and conformational variability of the i-motif in terms of base pairing and specific loop motions. The human telomeric i-motif is found to acquire various metastable folded conformations at pH values near the pKa of cytosine with the formation of a noncanonical C:C W:W trans base pair along with the hemiprotonated C:C+ pairs in the i-motif core. pH-dependent dynamics and the local solvent structure of i-motif DNA imply that the presence of a cosolvent or molecular crowding can promote i-motif formation in vivo by changing the conformational fluctuations and hydration state of the structure.
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Affiliation(s)
- Manas Mondal
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, 518107 Shenzhen, China
| | - Yi Qin Gao
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, 518107 Shenzhen, China
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University, 100871 Beijing, China
- Biomedical Pioneering Innovation Center, Peking University, 100871 Beijing, China
- Beijing Advanced Innovation Center for Genomics, Peking University, 100871 Beijing, China
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17
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Noble BB, Todorova N, Yarovsky I. Electromagnetic bioeffects: a multiscale molecular simulation perspective. Phys Chem Chem Phys 2022; 24:6327-6348. [PMID: 35245928 DOI: 10.1039/d1cp05510k] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Electromagnetic bioeffects remain an enigma from both the experimental and theoretical perspectives despite the ubiquitous presence of related technologies in contemporary life. Multiscale computational modelling can provide valuable insights into biochemical systems and predict how they will be perturbed by external stimuli. At a microscopic level, it can be used to determine what (sub)molecular scale reactions various stimuli might induce; at a macroscopic level, it can be used to examine how these changes affect dynamic behaviour of essential molecules within the crowded biomolecular milieu in living tissues. In this review, we summarise and evaluate recent computational studies that examined the impact of externally applied electric and electromagnetic fields on biologically relevant molecular systems. First, we briefly outline the various methodological approaches that have been employed to study static and oscillating field effects across different time and length scales. The practical value of such modelling is then illustrated through representative case-studies that showcase the diverse effects of electric and electromagnetic field on the main physiological solvent - water, and the essential biomolecules - DNA, proteins, lipids, as well as some novel biomedically relevant nanomaterials. The implications and relevance of the theoretical multiscale modelling to practical applications in therapeutic medicine are also discussed. Finally, we summarise ongoing challenges and potential opportunities for theoretical modelling to advance the current understanding of electromagnetic bioeffects for their modulation and/or beneficial exploitation in biomedicine and industry.
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Affiliation(s)
- Benjamin B Noble
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Australia. .,Australian Centre for Electromagnetic Bioeffects Research, Australia
| | - Nevena Todorova
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Australia. .,Australian Centre for Electromagnetic Bioeffects Research, Australia
| | - Irene Yarovsky
- School of Engineering, RMIT University, GPO Box 2476, Melbourne, Australia. .,Australian Centre for Electromagnetic Bioeffects Research, Australia
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18
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Lv P, Yang Y, Li S, Tan CS, Ming D. Biological nanopore approach for single‐molecule analysis of nucleobase modifications. ELECTROCHEMICAL SCIENCE ADVANCES 2021. [DOI: 10.1002/elsa.202100119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Pengrui Lv
- Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin China
| | - Yongyi Yang
- Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin China
| | - Shuang Li
- Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin China
| | - Cherie S. Tan
- Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin China
| | - Dong Ming
- Academy of Medical Engineering and Translational Medicine Tianjin University Tianjin China
- Department of Biomedical Engineering College of Precision Instruments and Optoelectronics Engineering Tianjin University Tianjin China
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19
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Petrunina NA, Lebedev VV, Kirillova YG, Aralov AV, Varizhuk AM, Sardushkin MV. DNA Intercalated Motifs with Non-Nucleoside Inserts. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2021. [DOI: 10.1134/s1068162021060212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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20
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Liu J, Li W, Li R, Yin X, He S, Hu J, Ruan S. Programmable DNA Framework Sensors for In Situ Cell-Surface pH Analysis. Anal Chem 2021; 93:12170-12174. [PMID: 34448560 DOI: 10.1021/acs.analchem.1c03227] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The availability of strategies for developing sensors with a defined responsiveness as well as the ability to working in a biological environment is critical to the fields of bioanalysis, nanomedicine, and nanorobotics. Herein, we developed programmable pH sensors by employing a tetrahedral DNA framework (TDF) as a robust structural skeleton for the sensors in biological working scenes and DNA i-motif structures as proton-recognition probes. The sensors' response midpoint and dynamic range can be fine-tuned by deliberately altering the i-motif's sequence composition or by combining different sensors, affording pH response windows that are consecutively distributed in the biologically relevant pH range of 5.0-7.5. This controllable tunability was successfully employed for in situ cell-surface pH analysis after anchoring the i-motif-TDF nanosensor on the cell surface via a two-step anchoring strategy, providing a useful platform for the diagnostics of diseases associated with extracellular pH variations.
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Affiliation(s)
- Jingxin Liu
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Weiwu Li
- Physikalisches Institut, Universität Stuttgart, Stuttgart 70569, Germany
| | - Rongsong Li
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Xiuzhao Yin
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Shiliang He
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China
| | - Junqing Hu
- College of Health Science and Environmental Engineering, Shenzhen Technology University, Shenzhen 518118, China.,Shenzhen Bey Laboratory, Shenzhen 518132, China
| | - Shuangchen Ruan
- College of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, China.,Shenzhen Key Laboratory of Laser Engineering, Shenzhen University, Shenzhen 518060, China
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21
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Serrano-Chacón I, Mir B, Escaja N, González C. Structure of i-Motif/Duplex Junctions at Neutral pH. J Am Chem Soc 2021; 143:12919-12923. [PMID: 34370473 PMCID: PMC8397320 DOI: 10.1021/jacs.1c04679] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
We report here the three-dimensional structure of an i-motif/duplex junction, determined by NMR methods at neutral pH. By including a minor groove tetrad at one side of the C:C+ stack of a monomeric i-motif, and a stem/loop hairpin at the other side, we have designed stable DNA constructs in which i-DNA and B-DNA regions coexist in a wide range of experimental conditions. This study demonstrates that i- and B-DNA are structurally compatible, giving rise to a distinctive fold with peculiar groove shapes. The effect of different residues at the i-motif/duplex interface has been explored. We also show that these constructs can be adapted to sequences of biological relevance, like that found in the promoter region of the KRAS oncogene.
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Affiliation(s)
| | - Bartomeu Mir
- Inorganic and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain
| | - Núria Escaja
- Inorganic and Organic Chemistry Department, Organic Chemistry Section, and IBUB, University of Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain.,BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain.,BIOESTRAN associated unit UB-CSIC, 08028 Barcelona, Spain
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22
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Xi D, Cui M, Zhou X, Zhuge X, Ge Y, Wang Y, Zhang S. Nanopore-Based Single-Molecule Investigation of DNA Sequences with Potential to Form i-Motif Structures. ACS Sens 2021; 6:2691-2699. [PMID: 34237940 DOI: 10.1021/acssensors.1c00712] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
i-Motifs are DNA secondary structures present in cytosine-rich sequences. These structures are formed in regulatory regions of the human genome and play key regulatory roles. The investigation of sequences capable of forming i-motif structures at the single-molecule level is highly important. In this study, we used α-hemolysin nanopores to systematically study a series of DNA sequences at the nanometer scale by providing structure-dependent signature current signals to gain in-sights into the i-motif DNA sequence and structural stability. Increasing the length of the cytosine tract in a range of 3-10 nucleobases resulted in a longer translocation time through the pore, indicating improved stability. Changing the loop sequence and length in the sequences did not affect the formation of the i-motif structure but changed its stability. Importantly, the application of all-atom molecular dynamics simulations revealed the structural morphology of all sequences. Based on these results, we postulated a folding rule for i-motif formation, suggesting that thousands of cytosine-rich sequences in the human genome might fold into i-motif structures. Many of these were found in locations where structure formation is likely to play regulatory roles. These findings provide insights into the application of nanopores as a powerful tool for discovering potential i-motif-forming sequences and lay a foundation for future studies exploring the biological roles of i-motifs.
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Affiliation(s)
- Dongmei Xi
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Life Sciences, Linyi University, Linyi 276005, P. R. China
| | - Mengjie Cui
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, P. R. China
| | - Xin Zhou
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, P. R. China
| | - Xiao Zhuge
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, P. R. China
| | - Yaxian Ge
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, P. R. China
| | - Ying Wang
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Life Sciences, Linyi University, Linyi 276005, P. R. China
| | - Shusheng Zhang
- Shandong Provincial Key Laboratory of Detection Technology for Tumor Markers, College of Chemistry and Chemical Engineering, Linyi University, Linyi 276005, P. R. China
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23
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Abstract
Quadruplex structures have been identified in a plethora of organisms where they play important functions in the regulation of molecular processes, and hence have been proposed as therapeutic targets for many diseases. In this paper we report the extensive bioinformatic analysis of the SARS-CoV-2 genome and related viruses using an upgraded version of the open-source algorithm G4-iM Grinder. This version improves the functionality of the software, including an easy way to determine the potential biological features affected by the candidates found. The quadruplex definitions of the algorithm were optimized for SARS-CoV-2. Using a lax quadruplex definition ruleset, which accepts amongst other parameters two residue G- and C-tracks, 512 potential quadruplex candidates were discovered. These sequences were evaluated by their in vitro formation probability, their position in the viral RNA, their uniqueness and their conservation rates (calculated in over seventeen thousand different COVID-19 clinical cases and sequenced at different times and locations during the ongoing pandemic). These results were then compared subsequently to other Coronaviridae members, other Group IV (+)ssRNA viruses and the entire viral realm. Sequences found in common with other viral species were further analyzed and characterized. Sequences with high scores unique to the SARS-CoV-2 were studied to investigate the variations amongst similar species. Quadruplex formation of the best candidates were then confirmed experimentally. Using NMR and CD spectroscopy, we found several highly stable RNA quadruplexes that may be suitable therapeutic targets for the SARS-CoV-2.
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24
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Chaudhuri R, Fatma K, Dash J. Regulation of gene expression by targeting DNA secondary structures. J CHEM SCI 2021. [DOI: 10.1007/s12039-021-01898-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Cheng M, Chen J, Ju H, Zhou J, Mergny JL. Drivers of i-DNA Formation in a Variety of Environments Revealed by Four-Dimensional UV Melting and Annealing. J Am Chem Soc 2021; 143:7792-7807. [PMID: 33988990 DOI: 10.1021/jacs.1c02209] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
i-DNA is a four-stranded, pH-sensitive structure formed by cytosine-rich DNA sequences. Previous reports have addressed the conditions for formation of this motif in DNA in vitro and validated its existence in human cells. Unfortunately, these in vitro studies have often been performed under different experimental conditions, making comparisons difficult. To overcome this, we developed a four-dimensional UV melting and annealing (4DUVMA) approach to analyze i-DNA formation under a variety of conditions (e.g., pH, temperature, salt, crowding). Analysis of 25 sequences provided a global understanding of i-DNA formation under disparate conditions, which should ultimately allow the design of accurate prediction tools. For example, we found reliable linear correlations between the midpoint of pH transition and temperature (-0.04 ± 0.003 pH unit per 1.0 °C temperature increment) and between the melting temperature and pH (-23.8 ± 1.1 °C per pH unit increment). In addition, by analyzing the hysteresis between denaturing and renaturing profiles in both pH and thermal transitions, we found that loop length, nature of the C-tracts, pH, temperature, and crowding agents all play roles in i-DNA folding kinetics. Interestingly, our data indicate which conformer is more favorable for the sequences with an odd number of cytosine base pairs. Then the thermal and pH stabilities of "native" i-DNAs from human promoter genes were measured under near physiological conditions (pH 7.0, 37 °C). The 4DUVMA method can become a universal resource to analyze the properties of any i-DNA-prone sequence.
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Affiliation(s)
- Mingpan Cheng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China.,ARNA Laboratory, Université de Bordeaux, INSERM U1212, CNRS UMR5320, IECB, Pessac 33607, France
| | - Jielin Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jun Zhou
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Jean-Louis Mergny
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing 210023, China.,ARNA Laboratory, Université de Bordeaux, INSERM U1212, CNRS UMR5320, IECB, Pessac 33607, France.,Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, Palaiseau Cedex 91128, France
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26
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Cheng M, Qiu D, Tamon L, Ištvánková E, Víšková P, Amrane S, Guédin A, Chen J, Lacroix L, Ju H, Trantírek L, Sahakyan AB, Zhou J, Mergny J. Thermal and pH Stabilities of i‐DNA: Confronting in vitro Experiments with Models and In‐Cell NMR Data. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Mingpan Cheng
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
- ARNA Laboratory Université de Bordeaux, INSERM U 1212, CNRS UMR5320 IECB 33607 Pessac France
| | - Dehui Qiu
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
| | - Liezel Tamon
- MRC WIMM Centre for Computational Biology MRC Weatherall Institute of Molecular Medicine Radcliffe Department of Medicine University of Oxford Oxford OX3 9DS UK
| | - Eva Ištvánková
- Central European Institute of Technology Masaryk University 62500 Brno Czech Republic
| | - Pavlína Víšková
- Central European Institute of Technology Masaryk University 62500 Brno Czech Republic
| | - Samir Amrane
- ARNA Laboratory Université de Bordeaux, INSERM U 1212, CNRS UMR5320 IECB 33607 Pessac France
| | - Aurore Guédin
- ARNA Laboratory Université de Bordeaux, INSERM U 1212, CNRS UMR5320 IECB 33607 Pessac France
| | - Jielin Chen
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
| | - Laurent Lacroix
- IBENS Ecole Normale Supérieure CNRS INSERM PSL Research University 75005 Paris France
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
| | - Lukáš Trantírek
- Central European Institute of Technology Masaryk University 62500 Brno Czech Republic
| | - Aleksandr B. Sahakyan
- MRC WIMM Centre for Computational Biology MRC Weatherall Institute of Molecular Medicine Radcliffe Department of Medicine University of Oxford Oxford OX3 9DS UK
| | - Jun Zhou
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
| | - Jean‐Louis Mergny
- State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry & Chemical Engineering Nanjing University Nanjing 210023 China
- ARNA Laboratory Université de Bordeaux, INSERM U 1212, CNRS UMR5320 IECB 33607 Pessac France
- Laboratoire d'Optique et Biosciences Ecole Polytechnique CNRS INSERM Institut Polytechnique de Paris 91128 Palaiseau France
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27
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Wan L, Yi J, Lam SL, Lee HK, Guo P. 5-Methylcytosine Substantially Enhances the Thermal Stability of DNA Minidumbbells. Chemistry 2021; 27:6740-6747. [PMID: 33501691 DOI: 10.1002/chem.202005410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Indexed: 11/07/2022]
Abstract
Minidumbbell (MDB) is a recently identified non-B DNA structure that has been proposed to associate with genetic instabilities. It also serves as a functional structural motif in DNA nanotechnology. DNA molecular switches constructed using MDBs show instant and complete structural conversions with easy manipulations. The availability of stable MDBs can broaden their applications. In this work, we found that substitutions of cytosine with 5-methylcytosine could lead to a significant enhancement in the thermal stabilities of MDBs. Consecutive methylations of cytosine in MDBs brought about cumulative stabilization with a drastic increase in the melting temperature by 23 °C. NMR solution structures of two MDBs containing 5-methylcytosine residues have been successfully determined and revealed that the enhanced stabilities resulted primarily from favorable hydrophobic contacts, more stable base pairs and enhanced base-base stackings involving the methyl group of 5-methylcytosine.
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Affiliation(s)
- Liqi Wan
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Jie Yi
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, 510006, China
| | - Sik Lok Lam
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Hung Kay Lee
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Pei Guo
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, 510006, China
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28
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Gao B, Hou XM. Opposite Effects of Potassium Ions on the Thermal Stability of i-Motif DNA in Different Buffer Systems. ACS OMEGA 2021; 6:8976-8985. [PMID: 33842768 PMCID: PMC8028132 DOI: 10.1021/acsomega.0c06350] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 03/11/2021] [Indexed: 05/12/2023]
Abstract
i-motifs are noncanonical DNA structures formed via the stack of intercalating hemi-protonated C+: C base pairs in C-rich DNA strands and play essential roles in the regulation of gene expression. Here, we systematically investigated the impacts of K+ on i-motif DNA folding using different buffer systems. We found that i-motif structures display very different T m values at the same pH and ion strength in different buffer systems. More importantly, K+ disrupts the i-motif formed in the MES and Bis-Tris buffer; however, K+ stabilizes the i-motif in phosphate, citrate, and sodium cacodylate buffers. Next, we selected phosphate buffer and confirmed by single-molecule fluorescence resonance energy transfer that K+ indeed has the stabilizing effect on the folding of i-motif DNA from pH 5.8 to 8.0. Nonetheless, circular dichroism spectra further indicate that the structures formed by i-motif sequences at high K+ concentrations at neutral and alkaline pH are not i-motif but other types of higher-order structures and most likely C-hairpins. We finally proposed the mechanisms of how K+ plays the opposite roles in different buffer systems. The present study may provide new insights into our understanding of the formation and stability of i-motif DNA.
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Affiliation(s)
| | - Xi-Miao Hou
- . Phone: +86 29 8708 1664. Fax: +86 29 8708 1664
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29
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Cheng M, Qiu D, Tamon L, Ištvánková E, Víšková P, Amrane S, Guédin A, Chen J, Lacroix L, Ju H, Trantírek L, Sahakyan AB, Zhou J, Mergny JL. Thermal and pH Stabilities of i-DNA: Confronting in vitro Experiments with Models and In-Cell NMR Data. Angew Chem Int Ed Engl 2021; 60:10286-10294. [PMID: 33605024 DOI: 10.1002/anie.202016801] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Indexed: 12/22/2022]
Abstract
Recent studies indicate that i-DNA, a four-stranded cytosine-rich DNA also known as the i-motif, is actually formed in vivo; however, a systematic study on sequence effects on stability has been missing. Herein, an unprecedented number of different sequences (271) bearing four runs of 3-6 cytosines with different spacer lengths has been tested. While i-DNA stability is nearly independent on total spacer length, the central spacer plays a special role on stability. Stability also depends on the length of the C-tracts at both acidic and neutral pHs. This study provides a global picture on i-DNA stability thanks to the large size of the introduced data set; it reveals unexpected features and allows to conclude that determinants of i-DNA stability do not mirror those of G-quadruplexes. Our results illustrate the structural roles of loops and C-tracts on i-DNA stability, confirm its formation in cells, and allow establishing rules to predict its stability.
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Affiliation(s)
- Mingpan Cheng
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China.,ARNA Laboratory, Université de Bordeaux, INSERM U 1212, CNRS UMR5320, IECB, 33607, Pessac, France
| | - Dehui Qiu
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Liezel Tamon
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Eva Ištvánková
- Central European Institute of Technology, Masaryk University, 62500, Brno, Czech Republic
| | - Pavlína Víšková
- Central European Institute of Technology, Masaryk University, 62500, Brno, Czech Republic
| | - Samir Amrane
- ARNA Laboratory, Université de Bordeaux, INSERM U 1212, CNRS UMR5320, IECB, 33607, Pessac, France
| | - Aurore Guédin
- ARNA Laboratory, Université de Bordeaux, INSERM U 1212, CNRS UMR5320, IECB, 33607, Pessac, France
| | - Jielin Chen
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Laurent Lacroix
- IBENS, Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, 75005, Paris, France
| | - Huangxian Ju
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Lukáš Trantírek
- Central European Institute of Technology, Masaryk University, 62500, Brno, Czech Republic
| | - Aleksandr B Sahakyan
- MRC WIMM Centre for Computational Biology, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Jun Zhou
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Jean-Louis Mergny
- State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry & Chemical Engineering, Nanjing University, Nanjing, 210023, China.,ARNA Laboratory, Université de Bordeaux, INSERM U 1212, CNRS UMR5320, IECB, 33607, Pessac, France.,Laboratoire d'Optique et Biosciences, Ecole Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128, Palaiseau, France
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30
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Mondal M, Yang L, Cai Z, Patra P, Gao YQ. A perspective on the molecular simulation of DNA from structural and functional aspects. Chem Sci 2021; 12:5390-5409. [PMID: 34168783 PMCID: PMC8179617 DOI: 10.1039/d0sc05329e] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
As genetic material, DNA not only carries genetic information by sequence, but also affects biological functions ranging from base modification to replication, transcription and gene regulation through its structural and dynamic properties and variations. The motion and structural properties of DNA involved in related biological processes are also multi-scale, ranging from single base flipping to local DNA deformation, TF binding, G-quadruplex and i-motif formation, TAD establishment, compartmentalization and even chromosome territory formation, just to name a few. The sequence-dependent physical properties of DNA play vital role in all these events, and thus it is interesting to examine how simple sequence information affects DNA and the formation of the chromatin structure in these different hierarchical orders. Accordingly, molecular simulations can provide atomistic details of interactions and conformational dynamics involved in different biological processes of DNA, including those inaccessible by current experimental methods. In this perspective, which is mainly based on our recent studies, we provide a brief overview of the atomistic simulations on how the hierarchical structure and dynamics of DNA can be influenced by its sequences, base modifications, environmental factors and protein binding in the context of the protein-DNA interactions, gene regulation and structural organization of chromatin. We try to connect the DNA sequence, the hierarchical structures of DNA and gene regulation.
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Affiliation(s)
- Manas Mondal
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China
| | - Lijiang Yang
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China
| | - Zhicheng Cai
- Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China.,Biomedical Pioneering Innovation Center, Peking University 100871 Beijing China
| | - Piya Patra
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China .,Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China
| | - Yi Qin Gao
- Institute of Systems and Physical Biology, Shenzhen Bay Laboratory 518055 Shenzhen China .,Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, Peking University 100871 Beijing China.,Biomedical Pioneering Innovation Center, Peking University 100871 Beijing China.,Beijing Advanced Innovation Center for Genomics, Peking University 100871 Beijing China
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31
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MD-TSPC4: Computational Method for Predicting the Thermal Stability of I-Motif. Int J Mol Sci 2020; 22:ijms22010061. [PMID: 33374624 PMCID: PMC7793491 DOI: 10.3390/ijms22010061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 11/23/2022] Open
Abstract
I-Motif is a tetrameric cytosine-rich DNA structure with hemi-protonated cytosine: cytosine base pairs. Recent evidence showed that i-motif structures in human cells play regulatory roles in the genome. Therefore, characterization of novel i-motifs and investigation of their functional implication are urgently needed for comprehensive understanding of their roles in gene regulation. However, considering the complications of experimental investigation of i-motifs and the large number of putative i-motifs in the genome, development of an in silico tool for the characterization of i-motifs in the high throughput scale is necessary. We developed a novel computation method, MD-TSPC4, to predict the thermal stability of i-motifs based on molecular modeling and molecular dynamic simulation. By assuming that the flexibility of loops in i-motifs correlated with thermal stability within certain temperature ranges, we evaluated the correlation between the root mean square deviations (RMSDs) of model structures and the thermal stability as the experimentally obtained melting temperature (Tm). Based on this correlation, we propose an equation for Tm prediction from RMSD. We expect this method can be useful for estimating the overall structure and stability of putative i-motifs in the genome, which can be a starting point of further structural and functional studies of i-motifs.
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32
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Turaev AV, Isaakova EA, Severov VV, Bogomazova AN, Zatsepin TS, Sardushkin MV, Aralov AV, Lagarkova MA, Pozmogova GE, Varizhuk AM. Genomic DNA i-motifs as fast sensors responsive to near-physiological pH microchanges. Biosens Bioelectron 2020; 175:112864. [PMID: 33309217 DOI: 10.1016/j.bios.2020.112864] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 11/11/2020] [Accepted: 11/24/2020] [Indexed: 02/06/2023]
Abstract
We report the design of robust sensors for measuring intracellular pH, based on the native DNA i-motifs (iMs) found in neurodegeneration- or carcinogenesis-related genes. Those iMs appear to be genomic regulatory elements and might modulate transcription in response to pH stimuli. Given their intrinsic sensitivity to minor pH changes within the physiological range, such noncanonical DNA structures can be used as sensor core elements without additional modules other than fluorescent labels or quenchers. We focused on several iMs that exhibited fast folding/unfolding kinetics. Using stopped-flow techniques and FRET-melting/annealing assays, we confirmed that the rates of temperature-driven iM-ssDNA transitions correlate with the rates of the pH-driven transitions. Thus, we propose FRET-based hysteresis analysis as an express method for selecting sensors with desired kinetic characteristics. For the leading fast-response sensor, we optimized the labelling scheme and performed intracellular calibration. Unlike the commonly used small-molecule pH indicators, that sensor was transferred efficiently to cell nuclei. Considering its favourable kinetic characteristics, the sensor can be used for monitoring proton dynamics in the nucleus. These results argue that the 'genome-inspired' design is a productive approach to the development of biocompatible molecular tools.
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Affiliation(s)
- Anton V Turaev
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Ekaterina A Isaakova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Vjacheslav V Severov
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Alexandra N Bogomazova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia; Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Timofei S Zatsepin
- Skolkovo Institute of Science and Technology, Moscow Oblast, 143026, Russia
| | - Makar V Sardushkin
- Mendeleev University of Chemical Technology of Russia, Moscow, 125047, Russia
| | - Andrey V Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, 117997, Russia
| | - Maria A Lagarkova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia; Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Galina E Pozmogova
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia
| | - Anna M Varizhuk
- Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia; Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, 119435, Russia; Engelhardt Institute of Molecular Biology, Moscow, 119991, Russia.
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33
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Baptista FR, Devereux SJ, Gurung SP, Hall JP, Sazanovich IV, Towrie M, Cardin CJ, Brazier JA, Kelly JM, Quinn SJ. The influence of loops on the binding of the [Ru(phen) 2dppz] 2+ light-switch compound to i-motif DNA structures revealed by time-resolved spectroscopy. Chem Commun (Camb) 2020; 56:9703-9706. [PMID: 32699864 DOI: 10.1039/d0cc03702h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ultrafast time resolved infrared (TRIR) is used to report on the binding site of the "light-switch" complex [Ru(phen)2(dppz)]2+1 to i-motif structures in solution. Detailed information is provided due to perturbation of the local base vibrations by a 'Stark-like' effect which is used to establish the contribution of thymine base loop interactions to the binding site of 1 in this increasingly relevant DNA structure.
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34
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Rogers RA, Meyer MR, Stewart KM, Eyring GM, Fleming AM, Burrows CJ. Hysteresis in poly-2'-deoxycytidine i-motif folding is impacted by the method of analysis as well as loop and stem lengths. Biopolymers 2020; 112:e23389. [PMID: 33098582 DOI: 10.1002/bip.23389] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/06/2020] [Accepted: 06/11/2020] [Indexed: 02/06/2023]
Abstract
In DNA, i-motif (iM) folds occur under slightly acidic conditions when sequences rich in 2'-deoxycytidine (dC) nucleotides adopt consecutive dC self base pairs. The pH stability of an iM is defined by the midpoint in the pH transition (pHT ) between the folded and unfolded states. Two different experiments to determine pHT values via circular dichroism (CD) spectroscopy were performed on poly-dC iMs of length 15, 19, or 23 nucleotides. These experiments demonstrate two points: (1) pHT values were dependent on the titration experiment performed, and (2) pH-induced denaturing or annealing processes produced isothermal hysteresis in the pHT values. These results in tandem with model iMs with judicious mutations of dC to thymidine to favor particular folds found the hysteresis was maximal for the shorter poly-dC iMs and those with an even number of base pairs, while the hysteresis was minimal for longer poly-dC iMs and those with an odd number of base pairs. Experiments to follow the iM folding via thermal changes identified thermal hysteresis between the denaturing and annealing cycles. Similar trends were found to those observed in the CD experiments. The results demonstrate that the method of iM analysis can impact the pHT parameter measured, and hysteresis was observed in the pHT and Tm values.
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Affiliation(s)
- R Aaron Rogers
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
| | - Madeline R Meyer
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
| | - Kayla M Stewart
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
| | - Gabriela M Eyring
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
| | - Aaron M Fleming
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
| | - Cynthia J Burrows
- Department of Chemistry, University of Utah, Salt Lake City, Utah, U.S.A
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35
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Roach RJ, Garavís M, González C, Jameson GB, Filichev VV, Hale TK. Heterochromatin protein 1α interacts with parallel RNA and DNA G-quadruplexes. Nucleic Acids Res 2020; 48:682-693. [PMID: 31799602 PMCID: PMC6954420 DOI: 10.1093/nar/gkz1138] [Citation(s) in RCA: 222] [Impact Index Per Article: 55.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 11/19/2019] [Accepted: 11/25/2019] [Indexed: 02/06/2023] Open
Abstract
The eukaryotic genome is functionally organized into domains of transcriptionally active euchromatin and domains of highly compact transcriptionally silent heterochromatin. Heterochromatin is constitutively assembled at repetitive elements that include the telomeres and centromeres. The histone code model proposes that HP1α forms and maintains these domains of heterochromatin through the interaction of its chromodomain with trimethylated lysine 9 of histone 3, although this interaction is not the sole determinant. We show here that the unstructured hinge domain, necessary for the targeting of HP1α to constitutive heterochromatin, recognizes parallel G-quadruplex (G4) assemblies formed by the TElomeric Repeat-containing RNA (TERRA) transcribed from the telomere. This provides a mechanism by which TERRA can lead to the enrichment of HP1α at telomeres to maintain heterochromatin. Furthermore, we show that HP1α binds with a faster association rate to DNA G4s of parallel topology compared to antiparallel G4s that bind slowly or not at all. Such G4–DNAs are found in the regulatory regions of several oncogenes. This implicates specific non-canonical nucleic acid structures as determinants of HP1α function and thus RNA and DNA G4s need to be considered as contributors to chromatin domain organization and the epigenome.
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Affiliation(s)
- Ruby J Roach
- School of Fundamental Sciences, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand
| | - Miguel Garavís
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain
| | - Geoffrey B Jameson
- School of Fundamental Sciences, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand.,Maurice Wilkins Centre, Private Bag 92019, Auckland, New Zealand
| | - Vyacheslav V Filichev
- School of Fundamental Sciences, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand.,Maurice Wilkins Centre, Private Bag 92019, Auckland, New Zealand
| | - Tracy K Hale
- School of Fundamental Sciences, Massey University, Private Bag 11-222, Palmerston North 4442, New Zealand.,Maurice Wilkins Centre, Private Bag 92019, Auckland, New Zealand
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36
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Shi L, Cao F, Zhang L, Tian Y. I-motif Formed at Physiological pH Triggered by Spatial Confinement of Nanochannels: An Electrochemical Platform for pH Monitoring in Brain Microdialysates. Anal Chem 2020; 92:4535-4540. [PMID: 32052626 DOI: 10.1021/acs.analchem.9b05732] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The development of switches responding to specific pH changes was particularly useful in wide application fields. Owing to flexible switches simulated by pH, i-motif DNAs are widely used as a pH sensor. But its character of structure transition strongly dependent on acidic pH severely hampers the application of i-motif DNA in physiological media. Herein, we report the stable i-motif structure formed at a physiological pH triggered by spatial confinement of silica nanochannels. Three classic DNA chains containing 21-mer i-motif domain base-pairs and a single-stranded multiply (T)n spacer, 5'-COOH-(T)n-CCCTAACCCTAACCCTAACCC-3', were employed to evaluate the enhanced stability of i-motif structure. Compared to their free states in a dilute solution, the transition pH of all i-motif DNAs decorated in nanochannels remarkably shifts toward a neutral pH. Moreover, the transition midpoint can be tuned sensitively over the physiologically relevant pH range through slightly varying the length of T base spacer. Density functional theory (DFT) calculations validate that the increased proton density in a nanochannel triggers the formation of an i-motif structure under a neutral pH. Finally, this i-motif DNA based nanochannels electrode was successfully employed to monitor pH in brain microdialysates followed by cerebral ischemia. The present approach is not limited by fundamental investigation for DNA conformation but may extend toward the manipulation of i-motif based structures for artificial molecular machines and signaling systems.
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Affiliation(s)
- Lu Shi
- School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Feifei Cao
- School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Limin Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
| | - Yang Tian
- School of Chemistry and Molecular Engineering, East China Normal University, Dongchuan Road 500, Shanghai 200241, China
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37
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Peng S, Bie B, Jia H, Tang H, Zhang X, Sun Y, Wei Q, Wu F, Yuan Y, Deng H, Zhou X. Efficient Separation of Nucleic Acids with Different Secondary Structures by Metal-Organic Frameworks. J Am Chem Soc 2020; 142:5049-5059. [PMID: 32069054 DOI: 10.1021/jacs.9b10936] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We report the use of metal-organic frameworks (MOFs) for the selective separation of nucleic acids (DNA and RNA) with different secondary structures through size, shape, length, and capability of conformational transition. Three MOFs with precisely controlled pore environments, Co-IRMOF-74-II, -III, and -IV, composed of Co2+ and organic linkers (II, III, and IV), respectively, were used for the inclusion of nucleic acid into their pores from the solution. This was proven to be a spontaneous process from disordered free state to restricted ordered state via circular dichroism (CD) spectroscopy. Three critical factors were identified for their inclusion: (1) size selection induced by steric hindrance, (2) conformation transition energy selection induced by stability, and (3) molecular weight selection. These selection rules were used to extract nucleic acids with flexible and unstable secondary structures from complex mixtures of multiple nucleic acids, leaving those with rigid and stable secondary structures in the mother liquor. This provides the possibility to separate and enrich nucleic acids in bulk through their different structure feature, which is highly desirable in genome-wide structural measurement of nucleic acids. Unlike methods that rely on specific binding antibodies or ligand, this MOF method is capable of selecting all kinds of nucleic acids with similar secondary structure features; therefore, it is suitable for the handling of a large variety and quantity of nucleic acids at the same time. This method also has the potential to gather information about the folding stability of biomolecules with secondary structures.
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Affiliation(s)
- Shuang Peng
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Binglin Bie
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.,The Institute of Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Hongnan Jia
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.,The Institute of Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Heng Tang
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Xiong Zhang
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Yuqing Sun
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Qi Wei
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Fan Wu
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Yushu Yuan
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Hexiang Deng
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.,The Institute of Advanced Studies, Wuhan University, Wuhan 430072, China
| | - Xiang Zhou
- Key Laboratory of Biomedical Polymers-Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
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38
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Megalathan A, Cox BD, Wilkerson PD, Kaur A, Sapkota K, Reiner JE, Dhakal S. Single-molecule analysis of i-motif within self-assembled DNA duplexes and nanocircles. Nucleic Acids Res 2019; 47:7199-7212. [PMID: 31287873 PMCID: PMC6698746 DOI: 10.1093/nar/gkz565] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 06/13/2019] [Accepted: 07/04/2019] [Indexed: 12/20/2022] Open
Abstract
The cytosine (C)-rich sequences that can fold into tetraplex structures known as i-motif are prevalent in genomic DNA. Recent studies of i-motif-forming sequences have shown increasing evidence of their roles in gene regulation. However, most of these studies have been performed in short single-stranded oligonucleotides, far from the intracellular environment. In cells, i-motif-forming sequences are flanked by DNA duplexes and packed in the genome. Therefore, exploring the conformational dynamics and kinetics of i-motif under such topologically constrained environments is highly relevant in predicting their biological roles. Using single-molecule fluorescence analysis of self-assembled DNA duplexes and nanocircles, we show that the topological environments play a key role on i-motif stability and dynamics. While the human telomere sequence (C3TAA)3C3 assumes i-motif structure at pH 5.5 regardless of topological constraint, it undergoes conformational dynamics among unfolded, partially folded and fully folded states at pH 6.5. The lifetimes of i-motif and the partially folded state at pH 6.5 were determined to be 6 ± 2 and 31 ± 11 s, respectively. Consistent with the partially folded state observed in fluorescence analysis, interrogation of current versus time traces obtained from nanopore analysis at pH 6.5 shows long-lived shallow blockades with a mean lifetime of 25 ± 6 s. Such lifetimes are sufficient for the i-motif and partially folded states to interact with proteins to modulate cellular processes.
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Affiliation(s)
- Anoja Megalathan
- Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA
| | - Bobby D Cox
- Department of Physics, Virginia Commonwealth University, 701 West Grace Street, Richmond, VA 23284, USA
| | - Peter D Wilkerson
- Department of Physics, Virginia Commonwealth University, 701 West Grace Street, Richmond, VA 23284, USA
| | - Anisa Kaur
- Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA
| | - Kumar Sapkota
- Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA
| | - Joseph E Reiner
- Department of Physics, Virginia Commonwealth University, 701 West Grace Street, Richmond, VA 23284, USA
| | - Soma Dhakal
- Department of Chemistry, Virginia Commonwealth University, 1001 West Main Street, Richmond, VA 23284, USA
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39
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Benabou S, Mazzini S, Aviñó A, Eritja R, Gargallo R. A pH-dependent bolt involving cytosine bases located in the lateral loops of antiparallel G-quadruplex structures within the SMARCA4 gene promotor. Sci Rep 2019; 9:15807. [PMID: 31676783 PMCID: PMC6825181 DOI: 10.1038/s41598-019-52311-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 10/15/2019] [Indexed: 01/01/2023] Open
Abstract
Some lung and ovarian tumors are connected to the loss of expression of SMARCA4 gene. In its promoter region, a 44-nucleotides long guanine sequence prone to form G-quadruplex structures has been studied by means of spectroscopic techniques (circular dichroism, molecular absorption and nuclear magnetic resonance), size exclusion chromatography and multivariate analysis. The results have shown that the central 21-nucleotides long sequence comprising four guanine tracts of disparate length is able to fold into a pH-dependent ensemble of G-quadruplex structures. Based on acid-base titrations and melting experiments of wild and mutated sequences, the formation of a C·C+ base pair between cytosine bases present at the two lateral loops is shown to promote a reduction in conformational heterogeneity, as well as an increase in thermal stability. The formation of this base pair is characterized by a pKa value of 7.1 ± 0.2 at 20 °C and 150 mM KCl. This value, higher than those usually found in i-motif structures, is related to the additional stability provided by guanine tetrads in the G-quadruplex. To our knowledge, this is the first thermodynamic description of this base pair in loops of antiparallel G-quadruplex structures.
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Affiliation(s)
- Sanae Benabou
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Barcelona, Spain
| | - Stefania Mazzini
- Department of Food, Environmental and Nutritional Sciences (DEFENS), University of Milan, Milan, Italy
| | - Anna Aviñó
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Ramon Eritja
- Institute for Advanced Chemistry of Catalonia (IQAC), CSIC, Networking Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Barcelona, Spain
| | - Raimundo Gargallo
- Department of Chemical Engineering and Analytical Chemistry, University of Barcelona, Barcelona, Spain.
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40
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Mondal M, Bhattacharyya D, Gao YQ. Structural properties and influence of solvent on the stability of telomeric four-stranded i-motif DNA. Phys Chem Chem Phys 2019; 21:21549-21560. [PMID: 31536074 DOI: 10.1039/c9cp03253c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Repetitive cytosine rich i-motif forming sequences are abundant in the telomere, centromere and promoters of several oncogenes and in some instances are known to regulate transcription and gene expression. The in vivo existence of i-motif structures demands further insight into the factors affecting their formation and stability and development of better understanding of their gene regulatory functions. Most prior studies characterizing the conformational dynamics of i-motifs are based on i-motif forming synthetic constructs. Here, we present a systematic study on the stability and structural properties of biologically relevant i-motifs of telomeric and centromeric repeat fragments. Our results based on molecular dynamics simulations and quantum chemical calculations indicate that along with base pairing interactions within the i-motif core the overall folded conformation is associated with the stable C-HO sugar "zippers" in the narrow grooves and structured water molecules along the wide grooves. The stacked geometry of the hemi-protonated cytosine pairs within the i-motif core is mainly governed by the repulsive base stacking interaction. The loop sequence can affect the structural dynamics of the i-motif by altering the loop motion and backbone conformation. Overall this study provides microscopic insight into the i-motif structure that will be helpful to understand the structural aspect of mechanisms of gene regulation by i-motif DNA.
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Affiliation(s)
- Manas Mondal
- Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing 100871, China.
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41
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Ma W, Chen B, Zou S, Jia R, Cheng H, Huang J, Wang H, He X, Wang K. I-Motif-Based in Situ Bipedal Hybridization Chain Reaction for Specific Activatable Imaging and Enhanced Delivery of Antisense Oligonucleotides. Anal Chem 2019; 91:12538-12545. [PMID: 31476869 DOI: 10.1021/acs.analchem.9b03420] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The efficient and precise delivery of antisense oligonucleotides (ASOs) to target cells is of great value in gene silencing. However, the specificity and packaging capacity of delivery system still remains challenging. Here, we designed an i-motif forming-initiated in situ bipedal hybridization chain reaction (pH-Apt-BiHCR) amplification strategy for specific target cells imaging and enhanced gene delivery of ASOs. As a proof of concept, an 8-nt ASO modified with locked nucleic acid (LNA) which is complementary to the seed region of microRNA21 (miR-21) was used for gene silencing studies. Benefiting from the design of hairpin-contained i-motif, the stimuli-responsive assembly of pH-Apt-BiHCR was successfully achieved on MCF-7 cells surface based on the specific recognition of aptamer. Using this strategy, the pH-Apt-BiHCR not only contains repeated fluorescence resonance energy transfer (FRET) units for activatable tumor imaging with high contrast but also arrays with plenty of LNA ASOs as interference molecules for cancer cells inhibition. An in vitro assay showed that this strategy presented an excellent response ability in buffer within a narrow pH range (6.0-7.0) with a transition midpoint (pHT) of 6.44 ± 0.06. Moreover, live cell studies revealed that it realized a specific activatable imaging of target cells, while the ASOs arrayed pH-Apt-BiHCR exhibited improved internalization via an endocytosis pathway and enhanced gene silencing to MCF-7 cells compared to single ASO alone. We believe that this design will inspire the development of novel probes for early diagnosis and therapy of cancer cells.
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Affiliation(s)
- Wenjie Ma
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Biao Chen
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Shanzi Zou
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Ruichen Jia
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Hong Cheng
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Jin Huang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Huizhen Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Xiaoxiao He
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
| | - Kemin Wang
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Hunan University , Key Laboratory for Bio-Nanotechnology and Molecule Engineering of Hunan Province , Changsha 410082 , China
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42
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Zhou YJ, Wan YH, Nie CP, Zhang J, Chen TT, Chu X. Molecular Switching of a Self-Assembled 3D DNA Nanomachine for Spatiotemporal pH Mapping in Living Cells. Anal Chem 2019; 91:10366-10370. [DOI: 10.1021/acs.analchem.9b02514] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Yu-Jie Zhou
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Yuan-Hui Wan
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Cun-Peng Nie
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Juan Zhang
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Ting-Ting Chen
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
| | - Xia Chu
- State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, P. R. China
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43
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Abou Assi H, Garavís M, González C, Damha MJ. i-Motif DNA: structural features and significance to cell biology. Nucleic Acids Res 2019; 46:8038-8056. [PMID: 30124962 PMCID: PMC6144788 DOI: 10.1093/nar/gky735] [Citation(s) in RCA: 239] [Impact Index Per Article: 47.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 08/13/2018] [Indexed: 12/20/2022] Open
Abstract
The i-motif represents a paradigmatic example of the wide structural versatility of nucleic acids. In remarkable contrast to duplex DNA, i-motifs are four-stranded DNA structures held together by hemi- protonated and intercalated cytosine base pairs (C:C+). First observed 25 years ago, and considered by many as a mere structural oddity, interest in and discussion on the biological role of i-motifs have grown dramatically in recent years. In this review we focus on structural aspects of i-motif formation, the factors leading to its stabilization and recent studies describing the possible role of i-motifs in fundamental biological processes.
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Affiliation(s)
- Hala Abou Assi
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
| | - Miguel Garavís
- Instituto de Química Física 'Rocasolano', CSIC, C/Serrano 119, 28006 Madrid, Spain
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, C/Serrano 119, 28006 Madrid, Spain
| | - Masad J Damha
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
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44
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Lepper CP, Williams MAK, Edwards PJB, Filichev VV, Jameson GB. Effects of Pressure and pH on the Physical Stability of an I‐Motif DNA Structure. Chemphyschem 2019; 20:1567-1571. [DOI: 10.1002/cphc.201900145] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/01/2019] [Indexed: 12/21/2022]
Affiliation(s)
| | - Martin A. K. Williams
- School of Fundamental Sciences The MacDiarmid Institute and the Riddet InstituteMassey University Palmerston North New Zealand
| | | | | | - Geoffrey B. Jameson
- School of Fundamental Sciences The MacDiarmid Institute and the Riddet InstituteMassey University Palmerston North New Zealand
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45
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Guo P, Lam SL. Unprecedented hydrophobic stabilizations from a reverse wobble T·T mispair in DNA minidumbbell. J Biomol Struct Dyn 2019; 38:1946-1953. [DOI: 10.1080/07391102.2019.1621211] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Pei Guo
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
| | - Sik Lok Lam
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong
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46
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Turaev AV, Tsvetkov VB, Tankevich MV, Smirnov IP, Aralov AV, Pozmogova GE, Varizhuk AM. Benzothiazole-based cyanines as fluorescent "light-up" probes for duplex and quadruplex DNA. Biochimie 2019; 162:216-228. [PMID: 31022429 DOI: 10.1016/j.biochi.2019.04.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 04/18/2019] [Indexed: 11/30/2022]
Abstract
Analogs of benzothiazole orange (BO) with one, two or three methylbenzothiazolylmethylidene substituents in the 1-methylpyridinium ring were obtained from the respective picolinium, lutidinium or collidinium salts. Fluorescence parameters of the known and new dyes in complexes with various DNA structures, including G-quadruplexes (G4s) and i-motifs (IMs), were analyzed. All dyes efficiently distinguished G4s and ss-DNA. The bi- and tri-substituted derivatives had basically similar distributions of relative fluorescence intensities. The mono-substituted derivatives exhibited enhanced sensitivity to parallel G4s. All dyes were particularly sensitive to a G4 structure with an additional duplex module (the thrombin-binding aptamer TBA31), presumably due to a distinctive binding mode (interaction with the junction between the two modules). In particular, BO showed a strong (160-fold) enhancement in fluorescence quantum yield in complex with TBA31 compared to the free dye. The fluorescence quantum yields of the 2,4-bisubstituted derivative in complex with well-characterized G4s from oncogene promoters were in the range of 0.04-0.28, i.e. comparable to those of ThT. The mono/bi-substituted derivatives should be considered as possible light-up probes for G4 formation.
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Affiliation(s)
- Anton V Turaev
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia; Moscow Institute of Physics and Technology, Institutsky Lane 9, Dolgoprudny, 141700, Russia
| | - Vladimir B Tsvetkov
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia; Department of Molecular Virology, FSBI Research Institute of Influenza, Ministry of Health of Russian Federation, Prof. Popov Str. 15/17, Saint-Petersburg, 197376, Russia; Computational Oncology Group, I.M. Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Str. 19/1, Moscow, 119146, Russia
| | - Maria V Tankevich
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia
| | - Igor P Smirnov
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia
| | - Andrey V Aralov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya Str. 16/10, Moscow, 117997, Russia.
| | - Galina E Pozmogova
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia; Institute of Bioengineering, Research Center of Biotechnology of the Russian Academy of Sciences, Leninsky Prospect, 33, Build. 2, Moscow, 119071, Russia.
| | - Anna M Varizhuk
- Biophysics Department, Research and Clinical Center for Physical Chemical Medicine, Malaya Pirogovskaya Str. 1a, Moscow, 119435, Russia; Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov Str. 32, Moscow, 119991, Russia
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47
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i-Motif DNA structures upon electric field exposure: completing the map of induced genetic errors. Theor Chem Acc 2019. [DOI: 10.1007/s00214-019-2423-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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48
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Debnath M, Fatma K, Dash J. Chemical Regulation of DNA i‐Motifs for Nanobiotechnology and Therapeutics. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813288] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Manish Debnath
- School of Chemical SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata- 700032 India
| | - Khushnood Fatma
- School of Chemical SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata- 700032 India
| | - Jyotirmayee Dash
- School of Chemical SciencesIndian Association for the Cultivation of Science Jadavpur Kolkata- 700032 India
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49
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Debnath M, Fatma K, Dash J. Chemical Regulation of DNA i-Motifs for Nanobiotechnology and Therapeutics. Angew Chem Int Ed Engl 2019; 58:2942-2957. [PMID: 30600876 DOI: 10.1002/anie.201813288] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 12/27/2018] [Indexed: 12/20/2022]
Abstract
DNA sequences rich in cytosine have the propensity, under acidic pH, to fold into four-stranded intercalated DNA structures called i-motifs. Recent studies have provided significant breakthroughs that demonstrate how chemists can manipulate these structures for nanobiotechnology and therapeutics. The first section of this Minireview discusses the development of advanced functional nanostructures by synthetic conjugation of i-motifs with organic scaffolds and metal nanoparticles and their role in therapeutics. The second section highlights the therapeutic targeting of i-motifs with chemical scaffolds and their significance in biology. For this, first we shed light on the long-lasting debate regarding the stability of i-motifs under physiological conditions. Next, we present a comparative analysis of recently reported small molecules for specifically targeting i-motifs over other abundant DNA structures and modulating their function in cellular systems. These advances provide new insights into i-motif-targeted regulation of gene expression, telomere maintenance, and therapeutic applications.
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Affiliation(s)
- Manish Debnath
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-, 700032, India
| | - Khushnood Fatma
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-, 700032, India
| | - Jyotirmayee Dash
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-, 700032, India
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50
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Ma Y, Mou Q, Zhu L, Su Y, Jin X, Feng J, Yan D, Zhu X, Zhang C. Polygemcitabine nanogels with accelerated drug activation for cancer therapy. Chem Commun (Camb) 2019; 55:6603-6606. [DOI: 10.1039/c9cc01506j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Polygemcitabine nanogels assembled from DNA-like polygemcitabine undergo rapid intracellular degradation to generate active gemcitabine derivatives for enhanced cancer therapy.
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Affiliation(s)
- Yuan Ma
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Quanbing Mou
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Lijuan Zhu
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Yue Su
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Xin Jin
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Jing Feng
- Shanghai University of Medicine & Health Sciences Affiliated Sixth People's Hospital South Campus
- Shanghai
- P. R. China
| | - Deyue Yan
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Xinyuan Zhu
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
| | - Chuan Zhang
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Metal Matrix Composites
- Shanghai Jiao Tong University
- Shanghai 200240
- P. R. China
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