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Li Y, Yang Y, Zhong C, Xiao D, Zhou C. Highly Sensitive Detection of T790 M with a Three-Level Characteristic Current by Thymine-Hg(II)-Thymine in the α-Hemolysin Nanopore. Anal Chem 2024; 96:3587-3592. [PMID: 38372205 DOI: 10.1021/acs.analchem.3c05571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Sensitive detection of resistance mutation T790 M is of great significance for early diagnosis and prognostic monitoring of non-small-cell lung cancer (NSCLC). In this paper, we showed a highly sensitive detection strategy for T790 M using a three-level characteristic current signal pattern in an α-hemolysin nanopore. A probe was designed that formed a C-T mismatched base pair with wild-type/P and a T-T mismatched with the T790M/P. The T790M/P produced a unique three-level characteristic current signal in the presence of mercury ions(II): first, T790M-Hg2+-P entering the vestibule of α-HL under the transmembrane potential and overhang of probe occupying the β-barrel, then probe unzipping from the T790M/P, T790 M temporally residing inside the nanocavity due to the interaction with Hg(II), and finally T790 M passing through the β-barrel. The blocking current distribution was concentrated with a small relative standard deviation of about 3%, and the signal peaks of T790 M and wild-type can be completely separated with a high separation resolution of more than 2.5, which achieved the highly sensitive detection of T790 M down to 0.001 pM (confidence level P 95%) with a linear range from 0.001 pM to 1 nM in human serum samples. This highly sensitive recognition strategy enables the detection of low abundance T790 M and provides a method for prognostic monitoring in NSCLC patients.
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Affiliation(s)
- Yaping Li
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - Yongqi Yang
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - Chunmeng Zhong
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - Dan Xiao
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - Cuisong Zhou
- College of Chemistry, Sichuan University, Chengdu 610064, P. R. China
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2
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Vecchioni S, Lu B, Livernois W, Ohayon YP, Yoder JB, Yang CF, Woloszyn K, Bernfeld W, Anantram MP, Canary JW, Hendrickson WA, Rothschild LJ, Mao C, Wind SJ, Seeman NC, Sha R. Metal-Mediated DNA Nanotechnology in 3D: Structural Library by Templated Diffraction. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2210938. [PMID: 37268326 DOI: 10.1002/adma.202210938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 03/06/2023] [Indexed: 06/04/2023]
Abstract
DNA double helices containing metal-mediated DNA (mmDNA) base pairs are constructed from Ag+ and Hg2+ ions between pyrimidine:pyrimidine pairs with the promise of nanoelectronics. Rational design of mmDNA nanomaterials is impractical without a complete lexical and structural description. Here, the programmability of structural DNA nanotechnology toward its founding mission of self-assembling a diffraction platform for biomolecular structure determination is explored. The tensegrity triangle is employed to build a comprehensive structural library of mmDNA pairs via X-ray diffraction and generalized design rules for mmDNA construction are elucidated. Two binding modes are uncovered: N3-dominant, centrosymmetric pairs and major groove binders driven by 5-position ring modifications. Energy gap calculations show additional levels in the lowest unoccupied molecular orbitals (LUMO) of mmDNA structures, rendering them attractive molecular electronic candidates.
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Affiliation(s)
- Simon Vecchioni
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - Brandon Lu
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - William Livernois
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA
| | - Yoel P Ohayon
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - Jesse B Yoder
- IMCA-CAT, Argonne National Lab, Argonne, IL, 60439, USA
| | - Chu-Fan Yang
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - Karol Woloszyn
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - William Bernfeld
- Department of Chemistry, New York University, New York, NY, 10003, USA
- ASPIRE Program, King School, Stamford, CT, 06905, USA
| | - M P Anantram
- Department of Electrical and Computer Engineering, University of Washington, Seattle, WA, 98195, USA
| | - James W Canary
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - Wayne A Hendrickson
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, 10032, USA
| | - Lynn J Rothschild
- NASA Ames Research Center, Planetary Sciences Branch, Moffett Field, CA, 94035, USA
| | - Chengde Mao
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
| | - Shalom J Wind
- Department of Applied Physics and Applied Math, Columbia University, New York, NY, 10027, USA
| | - Nadrian C Seeman
- Department of Chemistry, New York University, New York, NY, 10003, USA
| | - Ruojie Sha
- Department of Chemistry, New York University, New York, NY, 10003, USA
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3
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Nanodevices for Biological and Medical Applications: Development of Single-Molecule Electrical Measurement Method. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12031539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A comprehensive detection of a wide variety of diagnostic markers is required for the realization of personalized medicine. As a sensor to realize such personalized medicine, a single molecule electrical measurement method using nanodevices is currently attracting interest for its comprehensive simultaneous detection of various target markers for use in biological and medical application. Single-molecule electrical measurement using nanodevices, such as nanopore, nanogap, or nanopipette devices, has the following features:; high sensitivity, low-cost, high-throughput detection, easy-portability, low-cost availability by mass production technologies, and the possibility of integration of various functions and multiple sensors. In this review, I focus on the medical applications of single- molecule electrical measurement using nanodevices. This review provides information on the current status and future prospects of nanodevice-based single-molecule electrical measurement technology, which is making a full-scale contribution to realizing personalized medicine in the future. Future prospects include some discussion on of the current issues on the expansion of the application requirements for single-mole-cule measurement.
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4
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Tost J. Current and Emerging Technologies for the Analysis of the Genome-Wide and Locus-Specific DNA Methylation Patterns. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1389:395-469. [DOI: 10.1007/978-3-031-11454-0_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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5
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Luchian T, Mereuta L, Park Y, Asandei A, Schiopu I. Single-molecule, hybridization-based strategies for short nucleic acids detection and recognition with nanopores. Proteomics 2021; 22:e2100046. [PMID: 34275186 DOI: 10.1002/pmic.202100046] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 06/21/2021] [Accepted: 07/13/2021] [Indexed: 12/23/2022]
Abstract
DNA nanotechnology has seen large developments over the last 30 years through the combination of detection and discovery of DNAs, and solid phase synthesis to increase the chemical functionalities on nucleic acids, leading to the emergence of novel and sophisticated in features, nucleic acids-based biopolymers. Arguably, nanopores developed for fast and direct detection of a large variety of molecules, are part of a revolutionary technological evolution which led to cheaper, smaller and considerably easier to use devices enabling DNA detection and sequencing at the single-molecule level. Through their versatility, the nanopore-based tools proved useful biomedicine, nanoscale chemistry, biology and physics, as well as other disciplines spanning materials science to ecology and anthropology. This mini-review discusses the progress of nanopore- and hybridization-based DNA detection, and explores a range of state-of-the-art applications afforded through the combination of certain synthetically-derived polymers mimicking nucleic acids and nanopores, for the single-molecule biophysics on short DNA structures.
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Affiliation(s)
- Tudor Luchian
- Department of Physics, Alexandru I. Cuza University, Iasi, Romania
| | - Loredana Mereuta
- Department of Physics, Alexandru I. Cuza University, Iasi, Romania
| | - Yoonkyung Park
- Department of Biomedical Science and Research Center for Proteinaceous Materials (RCPM), Chosun University, Gwangju, Republic of Korea
| | - Alina Asandei
- Interdisciplinary Research Institute, Sciences Department, "Alexandru I. Cuza" University, Iasi, Romania
| | - Irina Schiopu
- Interdisciplinary Research Institute, Sciences Department, "Alexandru I. Cuza" University, Iasi, Romania
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6
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Zhang S, Huang J, Lu J, Liu M, Chen X, Su S, Mo F, Zheng J. Electrochemical and Optical Biosensing Strategies for DNA Methylation Analysis. Curr Med Chem 2020; 27:6159-6187. [DOI: 10.2174/0929867326666190903161750] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 07/24/2019] [Accepted: 08/07/2019] [Indexed: 12/14/2022]
Abstract
DNA methylation is considered as a crucial part of epigenetic modifications and a popular
research topic in recent decades. It usually occurs with a methyl group adding to the fifth carbon
atom of cytosine while the base sequence of DNA remains unchanged. DNA methylation has significant
influences on maintaining cell functions, genetic imprinting, embryonic development and
tumorigenesis procedures and hence the analysis of DNA methylation is of great medical significance.
With the development of analytical techniques and further research on DNA methylation,
numerous DNA methylation detection strategies based on biosensing technology have been developed
to fulfill various study requirements. This article reviewed the development of electrochemistry
and optical biosensing analysis of DNA methylation in recent years; in addition, we also reviewed
some recent advances in the detection of DNA methylation using new techniques, such as
nanopore biosensors, and highlighted the key technical and biological challenges involved in these
methods. We hope this paper will provide useful information for the selection and establishment of
analysis of DNA methylation.
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Affiliation(s)
- Shu Zhang
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Jian Huang
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing 400038, China
| | - Jingrun Lu
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Min Liu
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Xi Chen
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Shasha Su
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Fei Mo
- Department of Basic Clinical Laboratory Medicine, School of Clinical Laboratory Science, Guizhou Medical University, No. 9 Beijing Road, Yunyan District, Guiyang 550004, China
| | - Junsong Zheng
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, 30 Gaotanyan Street, Shapingba District, Chongqing 400038, China
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7
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Roozbahani GM, Chen X, Zhang Y, Wang L, Guan X. Nanopore detection of metal ions: Current status and future directions. SMALL METHODS 2020; 4:2000266. [PMID: 33365387 PMCID: PMC7751931 DOI: 10.1002/smtd.202000266] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Indexed: 05/27/2023]
Abstract
In this review, we highlight recent research efforts that aimed at developing nanopore sensors for detection of metal ions, which play a crucial role in environmental safety and human health. Protein pores use three stochastic sensing-based strategies for metal ion detection. The first strategy is to construct engineered nanopores with metal ion binding sites, so that the interaction between the target analytes and the nanopore can slow the movement of metal ions in the nano-channel. Second, large molecules such as nucleic acids and especially peptides could be utilized as external selective molecular probes to detect metal ions based on the conformational change of the ligand molecules induced by the metal ion-ligand chelation / coordination interaction. Third, enzymatic reactions can also be used as an alternative to the molecule probe strategy in the situation that a sensitive and selective probe molecule for the target analyte is difficult to obtain. On the other hand, by taking advantage of steady-state analysis, synthetic nanopores mainly use two strategies (modification and modification-free) to detect metals. Given the advantages of high sensitivity & selectivity, and label-free detection, nanopore-based metal ion sensors should find useful application in many fields, including environmental monitoring, medical diagnosis, and so on.
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Affiliation(s)
| | - Xiaohan Chen
- Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois, 60616, USA
| | - Youwen Zhang
- Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois, 60616, USA
| | - Liang Wang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
- The University of Chinese Academy of Science, Beijing, 100049, China
| | - Xiyun Guan
- Department of Chemistry, Illinois Institute of Technology, Chicago, Illinois, 60616, USA
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8
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Deng C, Naler LB, Lu C. Microfluidic epigenomic mapping technologies for precision medicine. LAB ON A CHIP 2019; 19:2630-2650. [PMID: 31338502 PMCID: PMC6697104 DOI: 10.1039/c9lc00407f] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Epigenomic mapping of tissue samples generates critical insights into genome-wide regulations of gene activities and expressions during normal development and disease processes. Epigenomic profiling using a low number of cells produced by patient and mouse samples presents new challenges to biotechnologists. In this review, we first discuss the rationale and premise behind profiling epigenomes for precision medicine. We then examine the existing literature on applying microfluidics to facilitate low-input and high-throughput epigenomic profiling, with emphasis on technologies enabling interfacing with next-generation sequencing. We detail assays on studies of histone modifications, DNA methylation, 3D chromatin structures and non-coding RNAs. Finally, we discuss what the future may hold in terms of method development and translational potential.
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Affiliation(s)
- Chengyu Deng
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA.
| | - Lynette B Naler
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA.
| | - Chang Lu
- Department of Chemical Engineering, Virginia Tech, Blacksburg, Virginia 24061, USA.
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9
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Syedmoradi L, Esmaeili F, Norton ML. Towards DNA methylation detection using biosensors. Analyst 2018; 141:5922-5943. [PMID: 27704092 DOI: 10.1039/c6an01649a] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
DNA methylation, a stable and heritable covalent modification which mostly occurs in the context of a CpG dinucleotide, has great potential as a biomarker to detect disease, provide prognoses and predict therapeutic responses. It can be detected in a quantitative manner by many different approaches both genome-wide and at specific gene loci, in various biological fluids such as urine, plasma, and serum, which can be obtained without invasive procedures. The current, classical methods are effective in studying DNA methylation patterns, however, for the most part; they have major drawbacks such as expensive instruments, complicated and time consuming protocols as well as relatively low sensitivity, and high false positive rates. To overcome these obstacles, great efforts have been made toward the development of reliable sensor devices to solve these limitations, providing sensitive, fast and cost-effective measurements. The use of biosensors for DNA methylation biomarkers has increased in recent years, because they are portable, simple, rapid, and inexpensive which offers a straightforward way to detect methylated biomarkers. In this review, we give an overview of the conventional techniques for the detection of DNA methylation and then will focus on recent advances in biosensor based methylation detection that eliminate bisulfite conversion and PCR amplification.
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Affiliation(s)
- Leila Syedmoradi
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Fariba Esmaeili
- Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Michael L Norton
- Department of Chemistry, Marshall University, One John Marshall Drive, Huntington, WV 25755, USA.
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10
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Schmidt OP, Benz AS, Mata G, Luedtke NW. HgII binds to C-T mismatches with high affinity. Nucleic Acids Res 2018; 46:6470-6479. [PMID: 29901748 PMCID: PMC6061796 DOI: 10.1093/nar/gky499] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 05/04/2018] [Accepted: 06/11/2018] [Indexed: 02/07/2023] Open
Abstract
Binding reactions of HgII and AgI to pyrimidine-pyrimidine mismatches in duplex DNA were characterized using fluorescent nucleobase analogs, thermal denaturation and 1H NMR. Unlike AgI, HgII exhibited stoichiometric, site-specific binding of C-T mismatches. The on- and off-rates of HgII binding were approximately 10-fold faster to C-T mismatches (kon ≈ 105 M-1 s-1, koff ≈ 10-3 s-1) as compared to T-T mismatches (kon ≈ 104 M-1 s-1, koff ≈ 10-4 s-1), resulting in very similar equilibrium binding affinities for both types of 'all natural' metallo base pairs (Kd ≈ 10-150 nM). These results are in contrast to thermal denaturation analyses, where duplexes containing T-T mismatches exhibited much larger increases in thermal stability upon addition of HgII (ΔTm = 6-19°C), as compared to those containing C-T mismatches (ΔTm = 1-4°C). In addition to revealing the high thermodynamic and kinetic stabilities of C-HgII-T base pairs, our results demonstrate that fluorescent nucleobase analogs enable highly sensitive detection and characterization of metal-mediated base pairs - even in situations where metal binding has little or no impact on the thermal stability of the duplex.
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Affiliation(s)
- Olivia P Schmidt
- University of Zurich, Department of Chemistry, Zurich, Switzerland
| | - Andrea S Benz
- University of Zurich, Department of Chemistry, Zurich, Switzerland
| | - Guillaume Mata
- University of Zurich, Department of Chemistry, Zurich, Switzerland
| | - Nathan W Luedtke
- University of Zurich, Department of Chemistry, Zurich, Switzerland
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11
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Liu L, Zhang Y, Jiang D, Du S, Deng Z, Wang L, Chen S. Recent Advances in the Genomic Profiling of Bacterial Epigenetic Modifications. Biotechnol J 2018; 14:e1800001. [PMID: 29878585 DOI: 10.1002/biot.201800001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 06/03/2018] [Indexed: 01/21/2023]
Affiliation(s)
- Liqiong Liu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
- Taihe Hospital; Hubei University of Medicine; Shiyan 442000 Hubei China
| | - Yizhou Zhang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
| | - Dongxu Jiang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
- Taihe Hospital; Hubei University of Medicine; Shiyan 442000 Hubei China
| | - Shiming Du
- Taihe Hospital; Hubei University of Medicine; Shiyan 442000 Hubei China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
- State Key Laboratory of Microbial Metabolism; School of Life Sciences and Biotechnology; Shanghai Jiao Tong University; Shanghai 200240 China
| | - Lianrong Wang
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
| | - Shi Chen
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery; Ministry of Education; School of Pharmaceutical Sciences; Zhongnan Hospital; Wuhan University; Wuhan 430071 China
- Taihe Hospital; Hubei University of Medicine; Shiyan 442000 Hubei China
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12
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Wang Y, Zhang Y, Guo Y, Kang XF. Fast and precise detection of DNA methylation with tetramethylammonium-filled nanopore. Sci Rep 2017; 7:183. [PMID: 28298646 PMCID: PMC5428259 DOI: 10.1038/s41598-017-00317-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 02/21/2017] [Indexed: 11/22/2022] Open
Abstract
The tremendous demand for detecting methylated DNA has stimulated intensive studies on developing fast single-molecule techniques with excellent sensitivity, reliability, and selectivity. However, most of these methods cannot directly detect DNA methylation at single-molecule level, which need either special recognizing elements or chemical modification of DNA. Here, we report a tetramethylammonium-based nanopore (termed TMA-NP) sensor that can quickly and accurately detect locus-specific DNA methylation, without bisulfite conversion, chemical modification or enzyme amplification. In the TMA-NP sensor, TMA-Cl is utilized as a nanopore-filling electrolyte to record the ion current change in a single nanopore triggered by methylated DNA translocation through the pore. Because of its methyl-philic nature, TMA can insert into the methylcytosine-guanine (mC-G) bond and then effectively unfasten and reduce the mC-G strength by 2.24 times. Simultaneously, TMA can increase the stability of A-T to the same level as C-G. The abilities of TMA (removing the base pair composition dependence of DNA strands, yet highly sensing for methylated base sites) endow the TMA-NP sensor with high selectivity and high precision. Using nanopore to detect dsDNA stability, the methylated and unmethylated bases are easily distinguished. This simple single-molecule technique should be applicable to the rapid analysis in epigenetic research.
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Affiliation(s)
- Ying Wang
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Yani Zhang
- College of Life Sciences, Northwest University, Xi'an, 710069, P. R. China
| | - Yanli Guo
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an, 710069, P. R. China
| | - Xiao-Feng Kang
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry, College of Chemistry & Materials Science, Northwest University, Xi'an, 710069, P. R. China.
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13
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Schmidt OP, Mata G, Luedtke NW. Fluorescent Base Analogue Reveals T-HgII-T Base Pairs Have High Kinetic Stabilities That Perturb DNA Metabolism. J Am Chem Soc 2016; 138:14733-14739. [DOI: 10.1021/jacs.6b09044] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Olivia P. Schmidt
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Guillaume Mata
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Nathan W. Luedtke
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
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14
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Asandei A, Schiopu I, Chinappi M, Seo CH, Park Y, Luchian T. Electroosmotic Trap Against the Electrophoretic Force Near a Protein Nanopore Reveals Peptide Dynamics During Capture and Translocation. ACS APPLIED MATERIALS & INTERFACES 2016; 8:13166-79. [PMID: 27159806 DOI: 10.1021/acsami.6b03697] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
We report on the ability to control the dynamics of a single peptide capture and passage across a voltage-biased, α-hemolysin nanopore (α-HL), under conditions that the electroosmotic force exerted on the analyte dominates the electrophoretic transport. We demonstrate that by extending outside the nanopore, the electroosmotic force is able to capture a peptide at either the lumen or vestibule entry of the nanopore, and transiently traps it inside the nanopore, against the electrophoretic force. Statistical analysis of the resolvable dwell-times of a metastable trapped peptide, as it occupies either the β-barrel or vestibule domain of the α-HL nanopore, reveals rich kinetic details regarding the direction and rates of stochastic movement of a peptide inside the nanopore. The presented approach demonstrates the ability to shuttle and study molecules along the passage pathway inside the nanopore, allows to identify the mesoscopic trajectory of a peptide exiting the nanopore through either the vestibule or β-barrel moiety, thus providing convincing proof of a molecule translocating the pore. The kinetic analysis of a peptide fluctuating between various microstates inside the nanopore, enabled a detailed picture of the free energy description of its interaction with the α-HL nanopore. When studied at the limit of vanishingly low transmembrane potentials, this provided a thermodynamic description of peptide reversible binding to and within the α-HL nanopore, under equilibrium conditions devoid of electric and electroosmotic contributions.
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Affiliation(s)
- Alina Asandei
- Department of Interdisciplinary Research, Alexandru I. Cuza University , Iasi 700506, Romania
| | - Irina Schiopu
- Department of Interdisciplinary Research, Alexandru I. Cuza University , Iasi 700506, Romania
| | - Mauro Chinappi
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia , Roma, Viale Regina Elena 291, 00161 , Italy
| | - Chang Ho Seo
- Department of Bioinformatics, Kongju National University , Kongju 314-701, South Korea
| | - Yoonkyung Park
- Department of Biomedical Science and Research Center for Proteineous Materials, Chosun University , Gwangju 61452, South Korea
| | - Tudor Luchian
- Department of Physics, Alexandru I. Cuza University , Iasi 700506, Romania
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15
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Poh WJ, Wee CPP, Gao Z. DNA Methyltransferase Activity Assays: Advances and Challenges. Am J Cancer Res 2016; 6:369-91. [PMID: 26909112 PMCID: PMC4737724 DOI: 10.7150/thno.13438] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/12/2015] [Indexed: 12/28/2022] Open
Abstract
DNA methyltransferases (MTases), a family of enzymes that catalyse the methylation of DNA, have a profound effect on gene regulation. A large body of evidence has indicated that DNA MTase is potentially a predictive biomarker closely associated with genetic disorders and genetic diseases like cancer. Given the attention bestowed onto DNA MTases in molecular biology and medicine, highly sensitive detection of DNA MTase activity is essential in determining gene regulation, epigenetic modification, clinical diagnosis and therapeutics. Conventional techniques such as isotope labelling are effective, but they often require laborious sample preparation, isotope labelling, sophisticated equipment and large amounts of DNA, rendering them unsuitable for uses at point-of-care. Simple, portable, highly sensitive and low-cost assays are urgently needed for DNA MTase activity screening. In most recent technological advances, many alternative DNA MTase activity assays such as fluorescent, electrochemical, colorimetric and chemiluminescent assays have been proposed. In addition, many of them are coupled with nanomaterials and/or enzymes to significantly enhance their sensitivity. Herein we review the progress in the development of DNA MTase activity assays with an emphasis on assay mechanism and performance with some discussion on challenges and perspectives. It is hoped that this article will provide a broad coverage of DNA MTase activity assays and their latest developments and open new perspectives toward the development of DNA MTase activity assays with much improved performance for uses in molecular biology and clinical practice.
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Current and Emerging Technologies for the Analysis of the Genome-Wide and Locus-Specific DNA Methylation Patterns. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 945:343-430. [DOI: 10.1007/978-3-319-43624-1_15] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Zhang X, Xu X, Yang Z, Burcke AJ, Gates KS, Chen SJ, Gu LQ. Mimicking Ribosomal Unfolding of RNA Pseudoknot in a Protein Channel. J Am Chem Soc 2015; 137:15742-52. [PMID: 26595106 PMCID: PMC4886178 DOI: 10.1021/jacs.5b07910] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Pseudoknots are a fundamental RNA tertiary structure with important roles in regulation of mRNA translation. Molecular force spectroscopic approaches such as optical tweezers can track the pseudoknot's unfolding intermediate states by pulling the RNA chain from both ends, but the kinetic unfolding pathway induced by this method may be different from that in vivo, which occurs during translation and proceeds from the 5' to 3' end. Here we developed a ribosome-mimicking, nanopore pulling assay for dissecting the vectorial unfolding mechanism of pseudoknots. The pseudoknot unfolding pathway in the nanopore, either from the 5' to 3' end or in the reverse direction, can be controlled by a DNA leader that is attached to the pseudoknot at the 5' or 3' ends. The different nanopore conductance between DNA and RNA translocation serves as a marker for the position and structure of the unfolding RNA in the pore. With this design, we provided evidence that the pseudoknot unfolding is a two-step, multistate, metal ion-regulated process depending on the pulling direction. Most notably, unfolding in both directions is rate-limited by the unzipping of the first helix domain (first step), which is Helix-1 in the 5' → 3' direction and Helix-2 in the 3' → 5' direction, suggesting that the initial unfolding step in either pulling direction needs to overcome an energy barrier contributed by the noncanonical triplex base-pairs and coaxial stacking interactions for the tertiary structure stabilization. These findings provide new insights into RNA vectorial unfolding mechanisms, which play an important role in biological functions including frameshifting.
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Affiliation(s)
- Xinyue Zhang
- Department of Bioengineering and Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, United States
| | - Xiaojun Xu
- Department of Physics, Department of Biochemistry, and Informatics Institute, University of Missouri, Columbia, Missouri 65211, United States
| | - Zhiyu Yang
- Department of Chemistry and Department of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
| | - Andrew J. Burcke
- Department of Bioengineering and Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, United States
| | - Kent S. Gates
- Department of Chemistry and Department of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
| | - Shi-Jie Chen
- Department of Physics, Department of Biochemistry, and Informatics Institute, University of Missouri, Columbia, Missouri 65211, United States
| | - Li-Qun Gu
- Department of Bioengineering and Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211, United States
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Wang Y, Gu LQ. Biomedical diagnosis perspective of epigenetic detections using alpha-hemolysin nanopore. AIMS MATERIALS SCIENCE 2015; 2:448-472. [PMID: 30931380 PMCID: PMC6436813 DOI: 10.3934/matersci.2015.4.448] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The α-hemolysin nanopore has been studied for applications in DNA sequencing, various single-molecule detections, biomolecular interactions, and biochips. The detection of single molecules in a clinical setting could dramatically improve cancer detection and diagnosis as well as develop personalized medicine practices for patients. This brief review shortly presents the current solid state and protein nanopore platforms and their applications like biosensing and sequencing. We then elaborate on various epigenetic detections (like microRNA, G-quadruplex, DNA damages, DNA modifications) with the most widely used alpha-hemolysin pore from a biomedical diagnosis perspective. In these detections, a nanopore electrical current signature was generated by the interaction of a target with the pore. The signature often was evidenced by the difference in the event duration, current level, or both of them. An ideal signature would provide obvious differences in the nanopore signals between the target and the background molecules. The development of cancer biomarker detection techniques and nanopore devices have the potential to advance clinical research and resolve health problems. However, several challenges arise in applying nanopore devices to clinical studies, including super low physiological concentrations of biomarkers resulting in low sensitivity, complex biological sample contents resulting in false signals, and fast translocating speed through the pore resulting in poor detections. These issues and possible solutions are discussed.
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Affiliation(s)
- Yong Wang
- Department of Biological Engineering, Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA
| | - Li-qun Gu
- Department of Biological Engineering, Dalton Cardiovascular Research Center, University of Missouri-Columbia, Columbia, MO 65211, USA
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Zeng T, Liu L, Li T, Li Y, Gao J, Zhao Y, Wu HC. Detection of 5-methylcytosine and 5-hydroxymethylcytosine in DNA via host-guest interactions inside α-hemolysin nanopores. Chem Sci 2015; 6:5628-5634. [PMID: 28757950 PMCID: PMC5510575 DOI: 10.1039/c5sc01436k] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/24/2015] [Indexed: 01/17/2023] Open
Abstract
After selective modification with a host–guest complex, 5-methylcytosine and 5-hydroxymethylcytosine in ssDNA can be unambiguously detected by the generation of characteristic current events during the translocation of the modified DNA through α-hemolysin nanopores.
Cytosine methylation and hydroxymethylation are both important epigenetic modifications of DNA in mammalian cells. Therefore, profiling DNA (hydroxy)methylation across the genome is vital for understanding their roles in gene regulation. Here, we report a nanopore-based approach for quick and reliable detection of 5-methylcytosine and 5-hydroxymethylcytosine in DNA at the single-molecule level. The single-stranded DNA containing 5-methylcytosine or 5-hydroxymethylcytosine was first selectively modified on the epigenetic base to attach a host–guest complex. Threading of the modified DNA molecules through α-hemolysin nanopores causes unbinding of the host–guest complex and generates highly characteristic current signatures. Statistical analysis of the signature events affords quantitative information about 5-methylcytosine and 5-hydroxymethylcytosine in DNA. Our results suggest that other DNA modifications could also be detected with the developed method. Furthermore, we anticipate our nanopore sensing strategy to be generally useful in biochemical analysis and to find applications in the early diagnosis of diseases.
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Affiliation(s)
- Tao Zeng
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745.,National Center for Nanoscience and Technology of China , Beijing 100190 , China .
| | - Lei Liu
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745
| | - Ting Li
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745
| | - Yuru Li
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745
| | - Juan Gao
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745
| | - Yuliang Zhao
- National Center for Nanoscience and Technology of China , Beijing 100190 , China .
| | - Hai-Chen Wu
- Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety , Institute of High Energy Physics , Chinese Academy of Sciences , Beijing 100049 , China . ; ; Tel: +86-10-88235745
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Taleat Z, Mathwig K, Sudhölter EJ, Rassaei L. Detection strategies for methylated and hypermethylated DNA. Trends Analyt Chem 2015. [DOI: 10.1016/j.trac.2014.11.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Shim J, Kim Y, Humphreys GI, Nardulli AM, Kosari F, Vasmatzis G, Taylor WR, Ahlquist DA, Myong S, Bashir R. Nanopore-based assay for detection of methylation in double-stranded DNA fragments. ACS NANO 2015; 9:290-300. [PMID: 25569824 DOI: 10.1021/nn5045596] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
DNA methylation is an epigenetic modification of DNA in which methyl groups are added at the 5-carbon position of cytosine. Aberrant DNA methylation, which has been associated with carcinogenesis, can be assessed in various biological fluids and potentially can be used as markers for detection of cancer. Analytically sensitive and specific assays for methylation targeting low-abundance and fragmented DNA are needed for optimal clinical diagnosis and prognosis. We present a nanopore-based direct methylation detection assay that circumvents bisulfite conversion and polymerase chain reaction amplification. Building on our prior work, we used methyl-binding proteins (MBPs), which selectively label the methylated DNA. The nanopore-based assay selectively detects methylated DNA/MBP complexes through a 19 nm nanopore with significantly deeper and prolonged nanopore ionic current blocking, while unmethylated DNA molecules were not detectable due to their smaller diameter. Discrimination of hypermethylated and unmethylated DNA on 90, 60, and 30 bp DNA fragments was demonstrated using sub-10 nm nanopores. Hypermethylated DNA fragments fully bound with MBPs are differentiated from unmethylated DNA at 2.1- to 6.5-fold current blockades and 4.5- to 23.3-fold transport durations. Furthermore, these nanopore assays can detect the CpG dyad in DNA fragments and could someday profile the position of methylated CpG sites on DNA fragments.
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Affiliation(s)
- Jiwook Shim
- Department of Bioengineering, ‡Micro and Nanotechnology Laboratory, and §Department of Molecular and Integrative Physiology, University of Illinois at Urbana-Champaign Urbana, Illinois 61801, United States
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Abstract
We provide an overview covering the existing challenges and latest developments in achieving high selectivity and sensitivity cancer-biomarker detection.
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Affiliation(s)
- Li Wu
- Laboratory of Chemical Biology and Division of Biological Inorganic Chemistry
- State Key laboratory of Rare Earth Resource Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
| | - Xiaogang Qu
- Laboratory of Chemical Biology and Division of Biological Inorganic Chemistry
- State Key laboratory of Rare Earth Resource Utilization
- Changchun Institute of Applied Chemistry
- Chinese Academy of Sciences
- Changchun
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Wang Y, Ritzo B, Gu LQ. Silver(I) ions modulate the stability of DNA duplexes containing cytosine, methylcytosine and hydroxymethylcytosine at different salt concentrations. RSC Adv 2014; 5:2655-2658. [PMID: 31007904 DOI: 10.1039/c4ra14490b] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Silver(I) ions can stabilize cytosine-cytosine, cytosine (C)-methylcytosine (5mC) and cytosine-hydroxymethylcytosine (5hmC) mismatched-base pairs. While cytosine modifications regulate DNA stability to regulate cellular functions, silver ions can modulate the stability of C-C, C-5mC and C-5hmC containing DNA duplexes in a salt concentration dependent manner.
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Affiliation(s)
- Yong Wang
- Department of Biological Engineering, University of Missouri, 134 research park, Columbia, MO 65211, USA. ; Tel: +1 573 8822086
| | - Brandon Ritzo
- Department of Biological Engineering, University of Missouri, 134 research park, Columbia, MO 65211, USA. ; Tel: +1 573 8822086
| | - Li-Qun Gu
- Department of Biological Engineering, University of Missouri, 134 research park, Columbia, MO 65211, USA. ; Tel: +1 573 8822086
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Wang Y, Tian K, Hunter LL, Ritzo B, Gu LQ. Probing molecular pathways for DNA orientational trapping, unzipping and translocation in nanopores by using a tunable overhang sensor. NANOSCALE 2014; 6:11372-9. [PMID: 25144935 PMCID: PMC6201287 DOI: 10.1039/c4nr03195d] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Nanopores provide a unique single-molecule platform for genetic and epigenetic detection. The target nucleic acids can be accurately analyzed by characterizing their specific electric fingerprints or signatures in the nanopore. Here we report a series of novel nanopore signatures generated by target nucleic acids that are hybridized with a probe. A length-tunable overhang appended to the probe functions as a sensor to specifically modulate the nanopore current profile. The resulting signatures can reveal multiple mechanisms for the orientational trapping, unzipping, escaping and translocation of nucleic acids in the nanopore. This universal approach can be used to program various molecular movement pathways, elucidate their kinetics, and enhance the sensitivity and specificity of the nanopore sensor for nucleic acid detection.
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Affiliation(s)
- Yong Wang
- Department of Bioengineering and Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA.
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Single molecule investigation of Ag+ interactions with single cytosine-, methylcytosine- and hydroxymethylcytosine-cytosine mismatches in a nanopore. Sci Rep 2014; 4:5883. [PMID: 25103463 PMCID: PMC4126007 DOI: 10.1038/srep05883] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 07/08/2014] [Indexed: 12/31/2022] Open
Abstract
Both cytosine-Ag-cytosine interactions and cytosine modifications in a DNA duplex have attracted great interest for research. Cytosine (C) modifications such as methylcytosine (mC) and hydroxymethylcytosine (hmC) are associated with tumorigenesis. However, a method for directly discriminating C, mC and hmC bases without labeling, modification and amplification is still missing. Additionally, the nature of coordination of Ag+ with cytosine-cytosine (C-C) mismatches is not clearly understood. Utilizing the alpha-hemolysin nanopore, we show that in the presence of Ag+, duplex stability is most increased for the cytosine-cytosine (C-C) pair, followed by the cytosine-methylcytosine (C-mC) pair, and the cytosine-hydroxymethylcytosine (C-hmC) pair, which has no observable Ag+ induced stabilization. Molecular dynamics simulations reveal that the hydrogen-bond-mediated paring of a C-C mismatch results in a binding site for Ag+. Cytosine modifications (such as mC and hmC) disrupted the hydrogen bond, resulting in disruption of the Ag+ binding site. Our experimental method provides a novel platform to study the metal ion-DNA interactions and could also serve as a direct detection method for nucleobase modifications.
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Abstract
PURPOSE OF REVIEW Epigenetic mechanisms of transcriptional regulation in atherosclerosis have gained an increasing interest in recent years. We focus on the relevance of DNA methylation, a well characterized epigenetic modification of the genome, as a biomarker and underlying mechanism of atherosclerosis. RECENT FINDINGS A growing number of loci have been identified, which are good candidate biomarkers for atherosclerosis and provide novel insights into the molecular changes taking place in the diseased vessel. Understanding the global change in DNA methylation during atherosclerosis remains a challenge. Novel unfolding research avenues include the interplay between genetic variants and DNA methylation patterns, and the role of long noncoding RNAs as epigenetic regulators. SUMMARY Epigenetics continues to represent a promising area of research in atherosclerosis. The full exploitation of cutting edge epigenomics will be decisive to define whether epigenetics will contribute to lower the burden of cardiovascular diseases.
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Affiliation(s)
- Silvio Zaina
- Department of Medical Sciences, Division of Health Sciences, Campus León, University of Guanajuato, León, Mexico
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