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Balouchi M, Huang SH, McGrath SL, Kobryn K. The telomere resolvase, TelA, utilizes an underwound pre-cleavage intermediate to promote hairpin telomere formation. PLoS One 2023; 18:e0294732. [PMID: 38019799 PMCID: PMC10686437 DOI: 10.1371/journal.pone.0294732] [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: 08/22/2023] [Accepted: 11/06/2023] [Indexed: 12/01/2023] Open
Abstract
The telomere resolvase, TelA, forms the hairpin telomeres of the linear chromosome of Agrobacterium tumefaciens in a process referred to as telomere resolution. Telomere resolution is a unique DNA cleavage and rejoining reaction that resolves replicated telomere junctions into a pair of hairpin telomeres. Telomere resolvases utilize a reaction mechanism with similarities to that of topoisomerase-IB enzymes and tyrosine recombinases. The reaction proceeds without the need for high-energy cofactors due to the use of a covalent, enzyme-cleaved DNA intermediate that stores the bond energy of the cleaved bonds in 3'-phosphotyrosyl linkages. The cleaved DNA strands are then refolded into a hairpin conformation and the 5'-OH ends of the refolded strands attack the 3'-phosphotyrosine linkages in order to rejoin the DNA strands into hairpin telomeres. Because this kind of reaction mechanism is, in principle, reversible it is unclear how TelA controls the direction of the reaction and propels the reaction to completion. We present evidence that TelA forms and/or stabilizes a pre-cleavage intermediate that features breakage of the four central basepairs between the scissile phosphates prior to DNA cleavage to help propel the reaction forwards, thus preventing abortive cleavage and rejoining cycles that regenerate the substrate DNA. We identify eight TelA sidechains, located in the hairpin-binding module and catalytic domains of TelA, implicated in this process. These mutants were deficient for telomere resolution on parental replicated telomere junctions but were rescued by introduction of substrate modifications that mimic unwinding of the DNA between the scissile phosphates.
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Affiliation(s)
- Mahrokh Balouchi
- Dept. of Biochemistry, Microbiology & Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Shu Hui Huang
- Dept. of Biochemistry, Microbiology & Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Siobhan L. McGrath
- The Global Institute for Food Security, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Kerri Kobryn
- Dept. of Biochemistry, Microbiology & Immunology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
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2
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Ma X, Zhang Y, Huang K, Zhu L, Xu W. Multifunctional rolling circle transcription-based nanomaterials for advanced drug delivery. Biomaterials 2023; 301:122241. [PMID: 37451000 DOI: 10.1016/j.biomaterials.2023.122241] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 06/21/2023] [Accepted: 07/06/2023] [Indexed: 07/18/2023]
Abstract
As the up-and-comer in the development of RNA nanotechnology, RNA nanomaterials based on functionalized rolling circle transcription (RCT) have become promising carriers for drug production and delivery. This is due to RCT technology can self-produce polyvalent tandem nucleic acid prodrugs for intervention in intracellular gene expression and protein production. RNA component strands participating in de novo assembly enable RCT-based nanomaterials to exhibit good mechanical properties, biostability, and biocompatibility as delivery carriers. The biostability makes it to suitable for thermodynamically/kinetically favorable assembly, enzyme resistance and efficient expression in vivo. Controllable RCT system combined with polymers enables customizable and adjustable size, shape, structure, and stoichiometry of RNA building materials, which provide groundwork for the delivery of advanced drugs. Here, we review the assembly strategies and the dynamic regulation of RCT-based nanomaterials, summarize its functional properties referring to the bottom-up design philosophy, and describe its advancements in tumor gene therapy, synergistic chemotherapy, and immunotherapy. Last, we elaborate on the unique and practical value of RCT-based nanomaterials, namely "self-production and self-sale", and their potential challenges in nanotechnology, material science and biomedicine.
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Affiliation(s)
- Xuan Ma
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, 100083, China; College of Food Science and Nutrition Engineering, China Agricultural University, Beijing, 100083, China
| | - Yangzi Zhang
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, 100083, China; College of Food Science and Nutrition Engineering, China Agricultural University, Beijing, 100083, China
| | - Kunlun Huang
- College of Food Science and Nutrition Engineering, China Agricultural University, Beijing, 100083, China
| | - Longjiao Zhu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, 100083, China
| | - Wentao Xu
- Key Laboratory of Precision Nutrition and Food Quality, Department of Nutrition and Health, China Agricultural University, Beijing, 100083, China; College of Food Science and Nutrition Engineering, China Agricultural University, Beijing, 100083, China.
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3
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Pruška A, Harrison JA, Granzhan A, Marchand A, Zenobi R. Solution and Gas-Phase Stability of DNA Junctions from Temperature-Controlled Electrospray Ionization and Surface-Induced Dissociation. Anal Chem 2023; 95:14384-14391. [PMID: 37699589 DOI: 10.1021/acs.analchem.3c02742] [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: 09/14/2023]
Abstract
DNA three-way junction (TWJ) structures transiently form during key cellular processes such as transcription, replication, and DNA repair. Despite their significance, the thermodynamics of TWJs, including the influence of strand length, base pair composition, and ligand binding on TWJ stability and dissociation mechanisms, are poorly understood. To address these questions, we interfaced temperature-controlled nanoelectrospray ionization mass spectrometry (TC-nESI-MS) with a cyclic ion mobility spectrometry (cIMS) instrument that was also equipped with a surface-induced dissociation (SID) stage. This novel combination allowed us to investigate the structural intermediates of three TWJ complexes and examine the effects of GC base pairs on their dissociation pathways. We found that two TWJ-specific ligands, 2,7-tris-naphthalene (2,7-TrisNP) and tris-phenoxybenzene (TrisPOB), lead to TWJ stabilization, revealed by an increase in the melting temperature (Tm) by 13 or 26 °C, respectively. To gain insights into conformational changes in the gas phase, we employed cIMS and SID to analyze TWJs and their complexes with ligands. Analysis of IM arrival distributions suggested a single-step dissociation of TWJs and their intermediates for the three studied TWJ complexes. Upon ligand binding, a higher SID energy by 3 V (2,7-TrisNP) and 5 V (TrisPOB) was required to induce 50% dissociation of TWJ, compared to 38 V in the absence of ligands. Our results demonstrate the power of utilizing TC-nESI-MS in combination with cIMS and SID for thermodynamic characterization of TWJ complexes and investigation of ligand binding. These techniques are essential for the TWJ design and development as drug targets, aptamers, and structural units for functional biomaterials.
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Affiliation(s)
- Adam Pruška
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Julian A Harrison
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Anton Granzhan
- CNRS UMR9187, Inserm U1196, Institut Curie, Paris Saclay University, F-91405 Orsay, France
| | - Adrien Marchand
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Renato Zenobi
- Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
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Zhang P, Ouyang Y, Zhuo Y, Chai Y, Yuan R. Recent Advances in DNA Nanostructures Applied in Sensing Interfaces and Cellular Imaging. Anal Chem 2023; 95:407-419. [PMID: 36625113 DOI: 10.1021/acs.analchem.2c04540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Pu Zhang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P.R. China
| | - Yu Ouyang
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P.R. China.,Institute of Chemistry, Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - Ying Zhuo
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P.R. China
| | - Yaqin Chai
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P.R. China
| | - Ruo Yuan
- Key Laboratory of Luminescence Analysis and Molecular Sensing (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, P.R. China
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Das S, Roy S, Bhattacharyya D. Understanding the role of non-Watson-Crick base pairs in DNA-protein recognition: Structural and energetic aspects using crystallographic database analysis and quantum chemical calculation. Biopolymers 2022; 113:e23492. [PMID: 35615897 DOI: 10.1002/bip.23492] [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: 02/16/2022] [Revised: 04/22/2022] [Accepted: 05/03/2022] [Indexed: 11/06/2022]
Abstract
Specific recognition of DNA base sequences by proteins is vital for life-cycles of all organisms. In a large number of crystal structures of protein-DNA complexes, DNA conformation significantly deviates from the canonical B-DNA structure. A key question is whether such alternate conformations exist prior to protein binding and one is selected for complexation or the structure observed is induced by protein binding. Non-canonical base pairs, such as Hoogsteen base pairs, are often observed in crystal structures of protein-DNA complexes. We decided to explore whether the occurrence of such non-canonical base pairs in protein-DNA complexes is induced by the protein or is selected from pre-existing conformations. Detailed quantum chemical calculations with dispersion-corrected density functional theory (DFT-D) indicated that most of the non-canonical base pairs with DNA bases are stable even in the absence of the interacting amino acids. However, the G:G Hoogsteen base pair, which also appears in the telomere structure, appears to be unstable in the absence of other stabilizing agents, such as positively charged amino acids. Thus, the stability of many of the non-canonical base pair containing duplexes may be close to the canonical B-DNA structure and hence energetically accessible in the ground state; suggesting that the selection from pre-existing conformations may be an important mechanism for observed non-canonical base pairs in protein-DNA complexes.
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Affiliation(s)
- Soumi Das
- Department of Biophysics, Bose Institute, Kolkata, India
| | - Siddhartha Roy
- Department of Biophysics, Bose Institute, Kolkata, India
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Selectively recognizing extrahelical conformations of DNA trinucleotide repeats by a hydroxylated porphyrin ligand. Anal Chim Acta 2022; 1190:339265. [PMID: 34857129 DOI: 10.1016/j.aca.2021.339265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 10/06/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022]
Abstract
Trinucleotide repeats (TRs) with abnormal lengths and atypical folding are implicated in various neurodegenerative diseases. The least stable cytosine-cytosine (C-C) mismatches in TRs when structuring into homoduplexes/hairpins have more chance in certain sequence contexts to preferentially adopt an extrahelical (E-motif) conformation with respect to those in polarity-inverted intrahelical counterparts. Herein, we designed a trihydroxyphenyl porphyrin ligand (POH3) to meet the challenge towards resolving the E-motif conformation. POH3 exhibited a specific 2:1 binding with DNAs adopting the E-motif cytosine conformation, independent of the TRs length. The trihydroxyl pattern was very crucial to gain the E-motif selectivity over the polarity-inverted counterparts via the complementary hydrogen bonding that occurred in the minor groove. Our work first elucidates the rationale in designing ligands to selectively resolve the E-motif nucleotides within TRs.
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7
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Zhang J, Ghadermarzi S, Katuwawala A, Kurgan L. DNAgenie: accurate prediction of DNA-type-specific binding residues in protein sequences. Brief Bioinform 2021; 22:6355416. [PMID: 34415020 DOI: 10.1093/bib/bbab336] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 07/02/2021] [Accepted: 07/28/2021] [Indexed: 01/02/2023] Open
Abstract
Efforts to elucidate protein-DNA interactions at the molecular level rely in part on accurate predictions of DNA-binding residues in protein sequences. While there are over a dozen computational predictors of the DNA-binding residues, they are DNA-type agnostic and significantly cross-predict residues that interact with other ligands as DNA binding. We leverage a custom-designed machine learning architecture to introduce DNAgenie, first-of-its-kind predictor of residues that interact with A-DNA, B-DNA and single-stranded DNA. DNAgenie uses a comprehensive physiochemical profile extracted from an input protein sequence and implements a two-step refinement process to provide accurate predictions and to minimize the cross-predictions. Comparative tests on an independent test dataset demonstrate that DNAgenie outperforms the current methods that we adapt to predict residue-level interactions with the three DNA types. Further analysis finds that the use of the second (refinement) step leads to a substantial reduction in the cross predictions. Empirical tests show that DNAgenie's outputs that are converted to coarse-grained protein-level predictions compare favorably against recent tools that predict which DNA-binding proteins interact with double-stranded versus single-stranded DNAs. Moreover, predictions from the sequences of the whole human proteome reveal that the results produced by DNAgenie substantially overlap with the known DNA-binding proteins while also including promising leads for several hundred previously unknown putative DNA binders. These results suggest that DNAgenie is a valuable tool for the sequence-based characterization of protein functions. The DNAgenie's webserver is available at http://biomine.cs.vcu.edu/servers/DNAgenie/.
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Affiliation(s)
- Jian Zhang
- School of Computer and Information Technology at the Xinyang Normal University, No.237, Nanhu Road, Xinyang 464000, Henan Province, P.R. China
| | - Sina Ghadermarzi
- Department of Computer Science at the Virginia Commonwealth University, 401 West Main Street, Room E4225, Richmond, Virginia 23284, USA
| | - Akila Katuwawala
- Department of Computer Science from the Virginia Commonwealth University, 401 West Main Street, Room E4225, Richmond, Virginia 23284, USA
| | - Lukasz Kurgan
- Department of Computer Science at the Virginia Commonwealth University, 401 West Main Street, Room E4225, Richmond, Virginia 23284, USA
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8
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Podder A, Lee HJ, Kim BH. Fluorescent Nucleic Acid Systems for Biosensors. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20200351] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Arup Podder
- Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Ha Jung Lee
- Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
| | - Byeang Hyean Kim
- Department of Chemistry, Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea
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9
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Triskova I, Veznik J, Lacina K, Trnkova L. Dramatic changes in the electrochemical and spectroscopic behavior of DNA fragments induced by the loss of a single nucleotide. Bioelectrochemistry 2020; 134:107515. [PMID: 32200262 DOI: 10.1016/j.bioelechem.2020.107515] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 03/13/2020] [Accepted: 03/13/2020] [Indexed: 12/17/2022]
Abstract
In this paper, the d(GCGAAGC) heptamer and the closely related d(GCGAGC) hexamer are examined via electrochemical (cyclic voltammetry) and spectroscopic (circular dichroism) methods. Dramatic changes in the CD spectroscopic and CV electrochemical properties, induced by the loss of only one single nucleotide (A), are detected. The CD spectra and native polyacrylamide gel electrophoresis (PAGE) confirmed structural changes taking place in the relevant chain-like oligodeoxynucleotide assemblies. Dedicated studies suggest that the heptamer (Hp) possesses a hairpin structure, whereas the hexamer (Hx) appears to be rather a duplex. Both of the structures exhibited completely different adsorption behavior at the hanging mercury drop electrode, and this factor was readily confirmed by means of elimination voltammetry with linear scan (EVLS). We established that the Hp hairpin (~-1300 mV), compared to the Hx duplex (~-1360 mV), is the thermodynamically favored electron acceptor. The adsorption isotherms were constructed based on the voltammetric peak height values, reflecting the reduction of the adenine (A) and cytosine (C) moieties as well as the oxidation of the 7,8-dihydroguanine (7,8-DHG) moieties. Finally, as revealed by the spectroscopic and electrochemical results, Hx forms a bimolecular antiparallel homo-duplex carrying both Watson-Crick base pairs (CG or GC) and mismatched edge-to-edge base pairs (GA or AG).
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Affiliation(s)
- Iveta Triskova
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic
| | - Jakub Veznik
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic; CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic
| | - Karel Lacina
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic
| | - Libuse Trnkova
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, CZ-625 00 Brno, Czech Republic.
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10
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Cechova M, Harris RS, Tomaszkiewicz M, Arbeithuber B, Chiaromonte F, Makova KD. High Satellite Repeat Turnover in Great Apes Studied with Short- and Long-Read Technologies. Mol Biol Evol 2019; 36:2415-2431. [PMID: 31273383 PMCID: PMC6805231 DOI: 10.1093/molbev/msz156] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 06/12/2019] [Accepted: 06/13/2019] [Indexed: 12/23/2022] Open
Abstract
Satellite repeats are a structural component of centromeres and telomeres, and in some instances, their divergence is known to drive speciation. Due to their highly repetitive nature, satellite sequences have been understudied and underrepresented in genome assemblies. To investigate their turnover in great apes, we studied satellite repeats of unit sizes up to 50 bp in human, chimpanzee, bonobo, gorilla, and Sumatran and Bornean orangutans, using unassembled short and long sequencing reads. The density of satellite repeats, as identified from accurate short reads (Illumina), varied greatly among great ape genomes. These were dominated by a handful of abundant repeated motifs, frequently shared among species, which formed two groups: 1) the (AATGG)n repeat (critical for heat shock response) and its derivatives; and 2) subtelomeric 32-mers involved in telomeric metabolism. Using the densities of abundant repeats, individuals could be classified into species. However, clustering did not reproduce the accepted species phylogeny, suggesting rapid repeat evolution. Several abundant repeats were enriched in males versus females; using Y chromosome assemblies or Fluorescent In Situ Hybridization, we validated their location on the Y. Finally, applying a novel computational tool, we identified many satellite repeats completely embedded within long Oxford Nanopore and Pacific Biosciences reads. Such repeats were up to 59 kb in length and consisted of perfect repeats interspersed with other similar sequences. Our results based on sequencing reads generated with three different technologies provide the first detailed characterization of great ape satellite repeats, and open new avenues for exploring their functions.
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Affiliation(s)
- Monika Cechova
- Department of Biology, Pennsylvania State University, University Park, PA
| | - Robert S Harris
- Department of Biology, Pennsylvania State University, University Park, PA
| | | | | | - Francesca Chiaromonte
- Department of Statistics, Pennsylvania State University, University Park, PA
- EMbeDS, Sant’Anna School of Advanced Studies, Pisa, Italy
- Center for Medical Genomics, Penn State, University Park, PA
| | - Kateryna D Makova
- Department of Biology, Pennsylvania State University, University Park, PA
- Center for Medical Genomics, Penn State, University Park, PA
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11
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Kingsland A, Maibaum L. DNA Base Pair Mismatches Induce Structural Changes and Alter the Free-Energy Landscape of Base Flip. J Phys Chem B 2018; 122:12251-12259. [DOI: 10.1021/acs.jpcb.8b06007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Addie Kingsland
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Lutz Maibaum
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
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12
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Sinha M, Mack H, Coleman TP, Fraley SI. A High-Resolution Digital DNA Melting Platform for Robust Sequence Profiling and Enhanced Genotype Discrimination. SLAS Technol 2018; 23:580-591. [DOI: 10.1177/2472630318769846] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
DNA melting analysis provides a rapid method for genotyping a target amplicon directly after PCR amplification. To transform melt genotyping into a broad-based profiling approach for heterogeneous samples, we previously proposed the integration of universal PCR and melt analysis with digital PCR. Here, we advanced this concept by developing a high-resolution digital melt platform with precise thermal control to accomplish reliable, high-throughput heat ramping of microfluidic chip digital PCR reactions. Using synthetic DNA oligos with defined melting temperatures, we characterized sources of melting variability and minimized run-to-run variations. Within-run comparisons throughout a 20,000-reaction chip revealed that high-melting-temperature sequences were significantly less prone to melt variation. Further optimization using bacterial 16S amplicons revealed a strong dependence of the number of melting transitions on the heating rate during curve generation. These studies show that reliable high-resolution melt curve genotyping can be achieved in digital, picoliter-scale reactions and demonstrate that rate-dependent melt signatures may be useful for enhancing automated melt genotyping.
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Affiliation(s)
- Mridu Sinha
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Clinical Translational Research Institute, University of California, San Diego, La Jolla, CA, USA
- Center for Microbiome Innovation, University of California, San Diego, La Jolla, CA, USA
| | - Hannah Mack
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Clinical Translational Research Institute, University of California, San Diego, La Jolla, CA, USA
- Center for Microbiome Innovation, University of California, San Diego, La Jolla, CA, USA
| | - Todd P. Coleman
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Center for Microbiome Innovation, University of California, San Diego, La Jolla, CA, USA
| | - Stephanie I. Fraley
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA
- Clinical Translational Research Institute, University of California, San Diego, La Jolla, CA, USA
- Center for Microbiome Innovation, University of California, San Diego, La Jolla, CA, USA
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13
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Zou X, Morganella S, Glodzik D, Davies H, Li Y, Stratton MR, Nik-Zainal S. Short inverted repeats contribute to localized mutability in human somatic cells. Nucleic Acids Res 2017; 45:11213-11221. [PMID: 28977645 PMCID: PMC5737083 DOI: 10.1093/nar/gkx731] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 07/14/2017] [Accepted: 08/10/2017] [Indexed: 01/09/2023] Open
Abstract
Selected repetitive sequences termed short inverted repeats (SIRs) have the propensity to form secondary DNA structures called hairpins. SIRs comprise palindromic arm sequences separated by short spacer sequences that form the hairpin stem and loop respectively. Here, we show that SIRs confer an increase in localized mutability in breast cancer, which is domain-dependent with the greatest mutability observed within spacer sequences (∼1.35-fold above background). Mutability is influenced by factors that increase the likelihood of formation of hairpins such as loop lengths (of 4-5 bp) and stem lengths (of 7-15 bp). Increased mutability is an intrinsic property of SIRs as evidenced by how almost all mutational processes demonstrate a higher rate of mutagenesis of spacer sequences. We further identified 88 spacer sequences showing enrichment from 1.8- to 90-fold of local mutability distributed across 283 sites in the genome that intriguingly, can be used to inform the biological status of a tumor.
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Affiliation(s)
- Xueqing Zou
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | | | - Dominik Glodzik
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Helen Davies
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Yilin Li
- Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland
| | | | - Serena Nik-Zainal
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
- East Anglian Medical Genetics Service, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 9NB, UK
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14
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Schöneweiß EC, Saccà B. The collective behavior of spring-like motifs tethered to a DNA origami nanostructure. NANOSCALE 2017; 9:4486-4496. [PMID: 28317958 DOI: 10.1039/c6nr08314e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Dynamic DNA nanotechnology relies on the integration of small switchable motifs at suitable positions of DNA nanostructures, thus enabling the manipulation of matter with nanometer spatial accuracy in a trigger-dependent fashion. Typical examples of such motifs are hairpins, whose elongation into duplexes can be used to perform long-range, translational movements. In this work, we used temperature-dependent FRET spectroscopy to determine the thermal stabilities of distinct sets of hairpins integrated into the central seam of a DNA origami structure. We then developed a hybrid spring model to describe the energy landscape of the tethered hairpins, combining the thermodynamic nearest-neighbor energy of duplex DNA with the entropic free energy of single-stranded DNA estimated using a worm-like chain approximation. We show that the organized scaffolding of multiple hairpins enhances the thermal stability of the device and that the coordinated action of the tethered motors can be used to mechanically unfold a G-quadruplex motif bound to the inner cavity of the origami structure, thus surpassing the operational capabilities of freely diffusing motors. Finally, we increased the complexity of device functionality through the insertion of two sets of parallel hairpins, resulting in four distinct states and in the reversible localization of desired molecules within the reconfigurable regions of the origami architecture.
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Affiliation(s)
- E-C Schöneweiß
- Centre for Medical Biotechnology (ZMB) and Centre for Nano Integration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitätstr. 2, 45117 Essen, Germany.
| | - B Saccà
- Centre for Medical Biotechnology (ZMB) and Centre for Nano Integration Duisburg-Essen (CENIDE), University of Duisburg-Essen, Universitätstr. 2, 45117 Essen, Germany.
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15
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Saoji M, Paukstelis PJ. Sequence-dependent structural changes in a self-assembling DNA oligonucleotide. ACTA CRYSTALLOGRAPHICA. SECTION D, BIOLOGICAL CRYSTALLOGRAPHY 2015; 71:2471-8. [PMID: 26627654 PMCID: PMC4667286 DOI: 10.1107/s1399004715019598] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/15/2015] [Indexed: 11/10/2022]
Abstract
DNA has proved to be a remarkable molecule for the construction of sophisticated two-dimensional and three-dimensional architectures because of its programmability and structural predictability provided by complementary Watson-Crick base pairing. DNA oligonucleotides can, however, exhibit a great deal of local structural diversity. DNA conformation is strongly linked to both environmental conditions and the nucleobase identities inherent in the oligonucleotide sequence, but the exact relationship between sequence and local structure is not completely understood. This study examines how a single-nucleotide addition to a class of self-assembling DNA 13-mers leads to a significantly different overall structure under identical crystallization conditions. The DNA 13-mers self-assemble in the presence of Mg(2+) through a combination of Watson-Crick and noncanonical base-pairing interactions. The crystal structures described here show that all of the predicted Watson-Crick base pairs are present, with the major difference being a significant rearrangement of noncanonical base pairs. This includes the formation of a sheared A-G base pair, a junction of strands formed from base-triple interactions, and tertiary interactions that generate structural features similar to tandem sheared G-A base pairs. The adoption of this alternate noncanonical structure is dependent in part on the sequence in the Watson-Crick duplex region. These results provide important new insights into the sequence-structure relationship of short DNA oligonucleotides and demonstrate a unique interplay between Watson-Crick and noncanonical base pairs that is responsible for crystallization fate.
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Affiliation(s)
- Maithili Saoji
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Paul J. Paukstelis
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
- Center for Biomolecular Structure and Organisation, Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
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16
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Nakano M, Tateishi-Karimata H, Tanaka S, Tama F, Miyashita O, Nakano SI, Sugimoto N. Thermodynamic properties of water molecules in the presence of cosolute depend on DNA structure: a study using grid inhomogeneous solvation theory. Nucleic Acids Res 2015; 43:10114-25. [PMID: 26538600 PMCID: PMC4666364 DOI: 10.1093/nar/gkv1133] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 10/14/2015] [Indexed: 01/11/2023] Open
Abstract
In conditions that mimic those of the living cell, where various biomolecules and other components are present, DNA strands can adopt many structures in addition to the canonical B-form duplex. Previous studies in the presence of cosolutes that induce molecular crowding showed that thermal stabilities of DNA structures are associated with the properties of the water molecules around the DNAs. To understand how cosolutes, such as ethylene glycol, affect the thermal stability of DNA structures, we investigated the thermodynamic properties of water molecules around a hairpin duplex and a G-quadruplex using grid inhomogeneous solvation theory (GIST) with or without cosolutes. Our analysis indicated that (i) cosolutes increased the free energy of water molecules around DNA by disrupting water–water interactions, (ii) ethylene glycol more effectively disrupted water–water interactions around Watson–Crick base pairs than those around G-quartets or non-paired bases, (iii) due to the negative electrostatic potential there was a thicker hydration shell around G-quartets than around Watson–Crick-paired bases. Our findings suggest that the thermal stability of the hydration shell around DNAs is one factor that affects the thermal stabilities of DNA structures under the crowding conditions.
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Affiliation(s)
- Miki Nakano
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan Advanced Institute for Computational Sciences, RIKEN, 7-1-26, Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Hisae Tateishi-Karimata
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Shigenori Tanaka
- Department of Computational Science, Graduate School of System Informatics, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe 657-8501, Japan
| | - Florence Tama
- Advanced Institute for Computational Sciences, RIKEN, 7-1-26, Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan Department of Physics, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Osamu Miyashita
- Advanced Institute for Computational Sciences, RIKEN, 7-1-26, Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Shu-Ichi Nakano
- Faculty of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20, Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe 650-0047, Japan
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17
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Lucyshyn D, Huang SH, Kobryn K. Spring loading a pre-cleavage intermediate for hairpin telomere formation. Nucleic Acids Res 2015; 43:6062-74. [PMID: 26007659 PMCID: PMC4499125 DOI: 10.1093/nar/gkv497] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 05/05/2015] [Indexed: 02/03/2023] Open
Abstract
The Borrelia telomere resolvase, ResT, forms the unusual hairpin telomeres of the linear Borrelia replicons in a process referred to as telomere resolution. Telomere resolution is a DNA cleavage and rejoining reaction that proceeds from a replicated telomere intermediate in a reaction with mechanistic similarities to that catalyzed by type IB topoisomerases. Previous reports have implicated the hairpin-binding module, at the end of the N-terminal domain of ResT, in distorting the DNA between the scissile phosphates so as to promote DNA cleavage and hairpin formation by the catalytic domain. We report that unwinding the DNA between the scissile phosphates, prior to DNA cleavage, is a key cold-sensitive step in telomere resolution. Through the analysis of ResT mutants, rescued by substrate modifications that mimic DNA unwinding between the cleavage sites, we show that formation and/or stabilization of an underwound pre-cleavage intermediate depends upon cooperation of the hairpin-binding module and catalytic domain. The phenotype of the mutants argues that the pre-cleavage intermediate promotes strand ejection to favor the forward reaction and that subsequent hairpin capture is a reversible reaction step. These reaction features are proposed to promote hairpin formation over strand resealing while allowing reversal back to substrate of aborted reactions.
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Affiliation(s)
- Danica Lucyshyn
- Department of Microbiology & Immunology, College of Medicine, University of Saskatchewan, Academic Health Sciences Building, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada
| | - Shu Hui Huang
- Department of Microbiology & Immunology, College of Medicine, University of Saskatchewan, Academic Health Sciences Building, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada
| | - Kerri Kobryn
- Department of Microbiology & Immunology, College of Medicine, University of Saskatchewan, Academic Health Sciences Building, 107 Wiggins Road, Saskatoon, SK S7N 5E5, Canada
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18
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Young RM, Singh APN, Thazhathveetil AK, Cho VY, Zhang Y, Renaud N, Grozema FC, Beratan DN, Ratner MA, Schatz GC, Berlin YA, Lewis FD, Wasielewski MR. Charge Transport across DNA-Based Three-Way Junctions. J Am Chem Soc 2015; 137:5113-22. [DOI: 10.1021/jacs.5b00931] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Ryan M. Young
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arunoday P. N. Singh
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arun K. Thazhathveetil
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Vincent Y. Cho
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuqi Zhang
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Nicolas Renaud
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - Ferdinand C. Grozema
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - David N. Beratan
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Mark A. Ratner
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - George C. Schatz
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuri A. Berlin
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Frederick D. Lewis
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
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19
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Kim KT, Heo W, Joo T, Kim BH. Photophysical and structural investigation of a PyA-modified adenine cluster: its potential use for fluorescent DNA probes exhibiting distinct emission color changes. Org Biomol Chem 2015; 13:8470-8. [DOI: 10.1039/c5ob01159k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A PyA-modified adenine cluster, exhibiting a large Stokes shift based on interstrand stacking interactions of adenines, was investigated and exploited as signaling parts of fluorescent DNA probes.
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Affiliation(s)
- Ki Tae Kim
- Department of Chemistry
- BK School of Molecular Science
- Pohang University of Science and Technology (POSTECH)
- Pohang 790-784
- South Korea
| | - Wooseok Heo
- Department of Chemistry
- BK School of Molecular Science
- Pohang University of Science and Technology (POSTECH)
- Pohang 790-784
- South Korea
| | - Taiha Joo
- Department of Chemistry
- BK School of Molecular Science
- Pohang University of Science and Technology (POSTECH)
- Pohang 790-784
- South Korea
| | - Byeang Hyean Kim
- Department of Chemistry
- BK School of Molecular Science
- Pohang University of Science and Technology (POSTECH)
- Pohang 790-784
- South Korea
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20
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Nakano M, Tateishi-Karimata H, Tanaka S, Sugimoto N. Affinity of Molecular Ions for DNA Structures Is Determined by Solvent-Accessible Surface Area. J Phys Chem B 2014; 118:9583-94. [DOI: 10.1021/jp505107g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
| | | | - Shigenori Tanaka
- Graduate
School of System Informatics, Department of Computational Science, Kobe University, 1-1, Rokkodai, Nada-ku, Kobe 657-8501, Japan
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21
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Ma Z, Jing X, Cheng J, Wang X, Lv Z. The effects of a short sequence enhancer (5′-GTGAAATAAATGCAAATAAAGT) and its derived sequences on green fluorescent protein expression. Genes Genomics 2014. [DOI: 10.1007/s13258-014-0180-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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22
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Abstract
Isolating a particular strand of DNA from a double stranded DNA duplex is an important step in aptamer generation as well as many other biotechnology applications. Here we describe a microfluidic, flow-through, dialysis device for isolating single-stranded DNA (ssDNA) from double-stranded DNA (dsDNA). The device consists of two channels fabricated in polydimethylsiloxane (PDMS) separated by a track etched polycarbonate membrane (800 nm pore size). To isolate ssDNA, dual-biotin labelled dsDNA was immobilized onto streptavidin-coated polystyrene beads. Alkaline treatment was used to denature dsDNA, releasing the non-biotinylated ssDNA. In the flow-through dialysis device the liberated ssDNA was able to cross the membrane and was collected in an outlet channel. The complementary sequence bound to the bead was unable to cross the membrane and was directed to a waste channel. The effect of NaOH concentration and flow rate on purity and yield were compared. >95% ssDNA purity was achieved at 25 mM NaOH. However, lower flow rates were necessary to achieve ssDNA yields approaching the 50% theoretical maximum of the concurrent-flow device. Under optimized conditions the microfluidic isolation achieved even higher purity ssDNA than analogous manual procedures.
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Affiliation(s)
- Yixiao Sheng
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA
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23
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Granzhan A, Kotera N, Teulade-Fichou MP. Finding needles in a basestack: recognition of mismatched base pairs in DNA by small molecules. Chem Soc Rev 2014; 43:3630-65. [DOI: 10.1039/c3cs60455a] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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24
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Betz K, Malyshev DA, Lavergne T, Welte W, Diederichs K, Romesberg FE, Marx A. Structural insights into DNA replication without hydrogen bonds. J Am Chem Soc 2013; 135:18637-43. [PMID: 24283923 PMCID: PMC3982147 DOI: 10.1021/ja409609j] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The genetic alphabet is composed of two base pairs, and the development of a third, unnatural base pair would increase the genetic and chemical potential of DNA. d5SICS-dNaM is one of the most efficiently replicated unnatural base pairs identified to date, but its pairing is mediated by only hydrophobic and packing forces, and in free duplex DNA it forms a cross-strand intercalated structure that makes its efficient replication difficult to understand. Recent studies of the KlenTaq DNA polymerase revealed that the insertion of d5SICSTP opposite dNaM proceeds via a mutually induced-fit mechanism, where the presence of the triphosphate induces the polymerase to form the catalytically competent closed structure, which in turn induces the pairing nucleotides of the developing unnatural base pair to adopt a planar Watson-Crick-like structure. To understand the remaining steps of replication, we now report the characterization of the prechemistry complexes corresponding to the insertion of dNaMTP opposite d5SICS, as well as multiple postchemistry complexes in which the already formed unnatural base pair is positioned at the postinsertion site. Unlike with the insertion of d5SICSTP opposite dNaM, addition of dNaMTP does not fully induce the formation of the catalytically competent closed state. The data also reveal that once synthesized and translocated to the postinsertion position, the unnatural nucleobases again intercalate. Two modes of intercalation are observed, depending on the nature of the flanking nucleotides, and are each stabilized by different interactions with the polymerase, and each appear to reduce the affinity with which the next correct triphosphate binds. Thus, continued primer extension is limited by deintercalation and rearrangements with the polymerase active site that are required to populate the catalytically active, triphosphate bound conformation.
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Affiliation(s)
- Karin Betz
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Denis A. Malyshev
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California, 92037
| | - Thomas Lavergne
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California, 92037
| | - Wolfram Welte
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Kay Diederichs
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
| | - Floyd E. Romesberg
- Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California, 92037
| | - Andreas Marx
- Departments of Chemistry and Biology, Konstanz Research School Chemical Biology, Universität Konstanz, Universitätsstrasse 10, D-78464 Konstanz, Germany
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25
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Molecular basis of recognition of quadruplexes human telomere and c-myc promoter by the putative anticancer agent sanguinarine. Biochim Biophys Acta Gen Subj 2013; 1830:4189-201. [DOI: 10.1016/j.bbagen.2013.03.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 03/19/2013] [Accepted: 03/26/2013] [Indexed: 01/24/2023]
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26
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Yandim C, Natisvili T, Festenstein R. Gene regulation and epigenetics in Friedreich's ataxia. J Neurochem 2013; 126 Suppl 1:21-42. [PMID: 23859339 DOI: 10.1111/jnc.12254] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/05/2013] [Accepted: 03/06/2013] [Indexed: 12/20/2022]
Abstract
This is an exciting time in the study of Friedreich's ataxia. Over the last 10 years much progress has been made in uncovering the mechanisms, whereby the Frataxin gene is silenced by (GAA)n repeat expansions and several of the findings are now ripe for testing in the clinic. The discovery that the Frataxin gene is heterochromatinised and that this can be antagonised in vivo has led to the tantalizing possibility that the disease might be amenable to a more radical therapeutic approach involving epigenetic modifiers. Here, we set out to review progress in the understanding of the fundamental mechanisms whereby genes are regulated at this level and how these findings have been applied to achieve a deeper understanding of the dysregulation that occurs as the primary genetic lesion in Friedreich's ataxia.
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Affiliation(s)
- Cihangir Yandim
- Gene Control Mechanisms and Disease, Department of Medicine and MRC Clinical Sciences Centre, Imperial College London, London, UK
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27
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Kolpashchikov DM. An elegant biosensor molecular beacon probe: challenges and recent solutions. SCIENTIFICA 2012; 2012:928783. [PMID: 24278758 PMCID: PMC3820487 DOI: 10.6064/2012/928783] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2012] [Accepted: 09/10/2012] [Indexed: 05/02/2023]
Abstract
Molecular beacon (MB) probes are fluorophore- and quencher-labeled short synthetic DNAs folded in a stem-loop shape. Since the first report by Tyagi and Kramer, it has become a widely accepted tool for nucleic acid analysis and triggered a cascade of related developments in the field of molecular sensing. The unprecedented success of MB probes stems from their ability to detect specific DNA or RNA sequences immediately after hybridization with no need to wash out the unbound probe (instantaneous format). Importantly, the hairpin structure of the probe is responsible for both the low fluorescent background and improved selectivity. Furthermore, the signal is generated in a reversible manner; thus, if the analyte is removed, the signal is reduced to the background. This paper highlights the advantages of MB probes and discusses the approaches that address the challenges in MB probe design. Variations of MB-based assays tackle the problem of stem invasion, improve SNP genotyping and signal-to-noise ratio, as well as address the challenges of detecting folded RNA and DNA.
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Affiliation(s)
- Dmitry M. Kolpashchikov
- Chemistry Department, University of Central Florida, 4000 Central Florida Boulevard, Orlando, FL 32816-2366, USA
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28
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Panyutin IG, Onyshchenko MI, Englund EA, Appella DH, Neumann RD. Targeting DNA G-quadruplex structures with peptide nucleic acids. Curr Pharm Des 2012; 18:1984-91. [PMID: 22376112 DOI: 10.2174/138161212799958440] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 11/28/2011] [Indexed: 11/22/2022]
Abstract
Regulation of genetic functions based on targeting DNA or RNA sequences with complementary oligonucleotides is especially attractive in the post-genome era. Oligonucleotides can be rationally designed to bind their targets based on simple nucleic acid base pairing rules. However, the use of natural DNA and RNA oligonucleotides as targeting probes can cause numerous off-target effects. In addition, natural nucleic acids are prone to degradation in vivo by various nucleases. To address these problems, nucleic acid mimics such as peptide nucleic acids (PNA) have been developed. They are more stable, show less off-target effects, and, in general, have better binding affinity to their targets. However, their high affinity to DNA can reduce their sequence-specificity. The formation of alternative DNA secondary structures, such as the G-quadruplex, provides an extra level of specificity as targets for PNA oligomers. PNA probes can target the loops of G-quadruplex, invade the core by forming PNA-DNA guanine-tetrads, or bind to the open bases on the complementary cytosine-rich strand. Not only could the development of such G-quadruplex-specific probes allow regulation of gene expression, but it will also provide a means to clarify the biological roles G-quadruplex structures may possess.
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29
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Renčiuk D, Zhou J, Beaurepaire L, Guédin A, Bourdoncle A, Mergny JL. A FRET-based screening assay for nucleic acid ligands. Methods 2012; 57:122-8. [PMID: 22465278 DOI: 10.1016/j.ymeth.2012.03.020] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 03/12/2012] [Accepted: 03/17/2012] [Indexed: 11/28/2022] Open
Abstract
Some of the most serious diseases are characterized by the presence of a specific secondary structure within DNA or RNA, often in the promoter or the coding region of the responsible gene, that enhances or disrupts expression of the protein. Structural elements that impact cellular function may also be formed in other genomic regions such as telomeres. Compounds that interact with such structural elements may be useful in diagnosis or treatment of patients. In this report, we present a FRET melting assay that allows testing of libraries of compounds against four different nucleic acid structures. Compounds are tested to determine whether they stabilize preformed secondary structures (i.e., whether they cause an increase in melting temperature (T(m))). This property is described by the ΔT(m) parameter, which is the difference between the T(m) of the compound-stabilized structure and the T(m) of the unbound structure. Model oligonucleotides are labeled with FAM as a fluorescent donor and TAMRA as an acceptor. The intensity of FAM fluorescence is recorded as a function of temperature. Melting temperatures are determined by the FRET method in 96-well plates; this assay could easily be converted into 384-well format.
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Affiliation(s)
- Daniel Renčiuk
- INSERM, U869, ARNA Laboratory, European Institute of Chemistry and Biology, 2 rue Robert Escarpit, F-33600 Pessac, France.
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30
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Kumari D, Usdin K. Is Friedreich ataxia an epigenetic disorder? Clin Epigenetics 2012; 4:2. [PMID: 22414340 PMCID: PMC3305337 DOI: 10.1186/1868-7083-4-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2011] [Accepted: 01/30/2012] [Indexed: 12/16/2022] Open
Abstract
Friedreich ataxia (FRDA) is a debilitating and frequently fatal neurological disorder that is recessively inherited. It belongs to the group of genetic disorders known as the Repeat Expansion Diseases, in which pathology arises from the deleterious consequences of the inheritance of a tandem repeat array whose repeat number exceeds a critical threshold. In the case of FRDA, the repeat unit is the triplet GAA•TTC and the tandem array is located in the first intron of the frataxin (FXN) gene. Pathology arises because expanded alleles make lower than normal levels of mature FXN mRNA and thus reduced levels of frataxin, the FXN gene product. The repeats form a variety of unusual DNA structures that have the potential to affect gene expression in a number of ways. For example, triplex formation in vitro and in bacteria leads to the formation of persistent RNA:DNA hybrids that block transcription. In addition, these repeats have been shown to affect splicing in model systems. More recently, it has been shown that the region flanking the repeats in the FXN gene is enriched for epigenetic marks characteristic of transcriptionally repressed regions of the genome. However, exactly how repeats in an intron cause the FXN mRNA deficit in FRDA has been the subject of much debate. Identifying the mechanism or mechanisms responsible for the FXN mRNA deficit in FRDA is important for the development of treatments for this currently incurable disorder. This review discusses evidence for and against different models for the repeat-mediated mRNA deficit.
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Affiliation(s)
- Daman Kumari
- Section on Gene Structure and Disease, Laboratory of Cell and Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA.
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31
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Baouendi M, Cognet JAH, Ferreira CSM, Missailidis S, Coutant J, Piotto M, Hantz E, Hervé du Penhoat C. Solution structure of a truncated anti-MUC1 DNA aptamer determined by mesoscale modeling and NMR. FEBS J 2012; 279:479-90. [PMID: 22129448 DOI: 10.1111/j.1742-4658.2011.08440.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Mucin 1 is a well-established target for the early diagnosis of epithelial cancers. The nucleotides of the S1.3/S2.2 DNA aptamer involved in binding to variable number tandem repeat mucin 1 peptides have been identified using footprinting experiments. The majority of these binding nucleotides are located in the 25-nucleotide variable region of the total aptamer. Imino proton and 2D NMR spectra of truncated and total aptamers in supercooled water reveal common hydrogen-bonding networks and point to a similar secondary structure for this 25-mer sequence alone or embedded within the total aptamer. NMR titration experiments confirm that the TTT triloop structure is the primary binding site and show that the initial structure of the truncated aptamers is conserved upon interaction with variable number tandem repeat peptides. The thermal dependence of the NMR chemical shift data shows that the base-paired nucleotides melt cooperatively at 47 ± 4°C. The structure of the 25-mer oligonucleotide was determined using a new combined mesoscale molecular modeling, molecular dynamics and NMR spectroscopy investigation. It contains three Watson-Crick pairs, three consecutive mispairs and four Watson-Crick pairs capped by a TTT triloop motif. The 3D model structures (PDB 2L5K) and biopolymer chain elasticity molecular models are consistent with both NMR and long unconstrained molecular dynamics (10 ns) in explicit water, respectively. Database Structural data are available in the Protein Data Bank and BioMagResBank databases under the accession numbers 2L5K and 17129, respectively.
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Affiliation(s)
- Meriem Baouendi
- Laboratoire Acides Nucléiques et Biophotonique, Université Pierre et Marie Curie Paris 6, Paris, France
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Kostyukov VV. Energetics of complex formation of the dna hairpin structure d(GCGAAGC) with aromatic ligands. Biophysics (Nagoya-shi) 2011. [DOI: 10.1134/s000635091101012x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Bartholomae CC, Arens A, Balaggan KS, Yáñez-Muñoz RJ, Montini E, Howe SJ, Paruzynski A, Korn B, Appelt JU, Macneil A, Cesana D, Abel U, Glimm H, Naldini L, Ali RR, Thrasher AJ, von Kalle C, Schmidt M. Lentiviral vector integration profiles differ in rodent postmitotic tissues. Mol Ther 2011; 19:703-10. [PMID: 21364536 DOI: 10.1038/mt.2011.19] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Lentiviral vectors with self-inactivating (SIN) long terminal repeats (LTRs) are promising for safe and sustained transgene expression in dividing as well as quiescent cells. As genome organization and transcription substantially differs between actively dividing and postmitotic cells in vivo, we hypothesized that genomic vector integration preferences might be distinct between these biological states. We performed integration site (IS) analyses on mouse dividing cells (fibroblasts and hematopoietic progenitor cells (HPCs)) transduced ex vivo and postmitotic cells (eye and brain) transduced in vivo. As expected, integration in dividing cells occurred preferably into gene coding regions. In contrast, postmitotic cells showed a close to random frequency of integration into genes and gene spare long interspersed nuclear elements (LINE). Our studies on the potential mechanisms responsible for the detected differences of lentiviral integration suggest that the lowered expression level of Psip1 reduce the integration frequency in vivo into gene coding regions in postmitotic cells. The motif TGGAA might represent one of the factors for preferred lentiviral integration into mouse and rat Satellite DNA. These observations are highly relevant for the correct assessment of preclinical biosafety studies, indicating that lentiviral vectors are well suited for safe and effective clinical gene transfer into postmitotic tissues.
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Affiliation(s)
- Cynthia C Bartholomae
- Department of Translational Oncology, National Center for Tumor Diseases (NCT) and German Cancer Research Center (DKFZ), Heidelberg, Germany
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Qing G, Xiong H, Seela F, Sun T. Spatially controlled DNA nanopatterns by "click" chemistry using oligonucleotides with different anchoring sites. J Am Chem Soc 2011; 132:15228-32. [PMID: 20936845 DOI: 10.1021/ja105246b] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
DNA patterning on surfaces has broad applications in biotechnology, nanotechnology, and other fields of life science. The common patterns make use of the highly selective base pairing which might not be stable enough for further manipulations. Furthermore, the fabrication of well-defined DNA nanostructures on solid surfaces usually lacks chemical linkages to the surface. Here we report a template-free strategy based on "click" chemistry to fabricate spatially controlled DNA nanopatterns immobilized on surfaces. The self-assembly process utilizes DNA with different anchoring sites. The position of anchoring is of crucial importance for the self-assembly process of DNA and greatly influences the assembly of particular DNA nanopatterns. It is shown that the anchoring site in a central position generates tunable nanonetworks with high regularity, compared to DNAs containing anchoring sites at terminal and other positions. The prepared patterns may find applications in DNA capturing and formation of pores and channels and can serve as templates for the patterning using other molecules.
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Affiliation(s)
- Guangyan Qing
- State Key Laboratory of Advanced Technology for Materials Synthesis and Composite, Wuhan University of Technology, Wuhan 430070, China
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35
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Malyshev DA, Pfaff DA, Ippoliti SI, Hwang GT, Dwyer TJ, Romesberg FE. Solution structure, mechanism of replication, and optimization of an unnatural base pair. Chemistry 2011; 16:12650-9. [PMID: 20859962 DOI: 10.1002/chem.201000959] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
As part of an ongoing effort to expand the genetic alphabet for in vitro and eventual in vivo applications, we have synthesized a wide variety of predominantly hydrophobic unnatural base pairs and evaluated their replication in DNA. Collectively, the results have led us to propose that these base pairs, which lack stabilizing edge-on interactions, are replicated by means of a unique intercalative mechanism. Here, we report the synthesis and characterization of three novel derivatives of the nucleotide analogue dMMO2, which forms an unnatural base pair with the nucleotide analogue d5SICS. Replacing the para-methyl substituent of dMMO2 with an annulated furan ring (yielding dFMO) has a dramatically negative effect on replication, while replacing it with a methoxy (dDMO) or with a thiomethyl group (dTMO) improves replication in both steady-state assays and during PCR amplification. Thus, dTMO-d5SICS, and especially dDMO-d5SICS, represent significant progress toward the expansion of the genetic alphabet. To elucidate the structure-activity relationships governing unnatural base pair replication, we determined the solution structure of duplex DNA containing the parental dMMO2-d5SICS pair, and also used this structure to generate models of the derivative base pairs. The results strongly support the intercalative mechanism of replication, reveal a surprisingly high level of specificity that may be achieved by optimizing packing interactions, and should prove invaluable for the further optimization of the unnatural base pair.
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Affiliation(s)
- Denis A Malyshev
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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36
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Arranz-Mascarós P, Bazzicalupi C, Bianchi A, Giorgi C, Godino-Salido ML, Gutiérrez-Valero MD, Lopez-Garzón R, Valtancoli B. Binding and recognition of AMP, ADP, ATP and related inorganic phosphate anions by a tren-based ligand containing a pyrimidine functionality. NEW J CHEM 2011. [DOI: 10.1039/c1nj20393b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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37
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Evstigneev MP, Parkinson JA, Lantushenko AO, Kostjukov VV, Pahomov VI. Hexamer oligonucleotide topology and assembly under solution phase NMR and theoretical modeling scrutiny. Biopolymers 2010; 93:1023-38. [PMID: 20623667 DOI: 10.1002/bip.21515] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The entire family of noncomplementary hexamer oligodeoxyribonucleotides d(GCXYGC) (X and Y = A, G, C, or T) were assessed for topological indicators and equilibrium thermodynamics using a priori molecular modeling and solution phase NMR spectroscopy. Feasible modeled hairpin structures formed a basis from which solution structure and equilibria for each oligonucleotide were considered. ¹H and ³¹P variable temperature-dependent (VT) and concentration-dependent NMR data, NMR signal assignments, and diffusion parameters led to d(GCGAGC) and d(GCGGGC) being understood as exceptions within the family in terms of self-association and topological character. A mean diffusion coefficient D(298 K) = (2.0 ± 0.07) × 10⁻¹⁰ m² s⁻¹ was evaluated across all hexamers except for d(GCGAGC) (D(298 K) = 1.7 × 10⁻¹⁰ m² s⁻¹) and d(GCGGGC) (D(298 K) = 1.2 × 10⁻¹⁰ m² s⁻¹). Melting under VT analysis (T(m) = 323 K) combined with supporting NMR evidence confirmed d(GCGAGC) as the shortest tandem sheared GA mismatched duplex. Diffusion measurements were used to conclude that d(GCGGGC) preferentially exists as the shortest stable quadruplex structure. Thermodynamic analysis of all data led to the assertion that, with the exception of XY = GA and GG, the remaining noncomplementary oligonucleotides adopt equilibria between monomer and duplex, contributed largely by monomer random-coil forms. Contrastingly, d(GCGAGC) showed preference for tandem sheared GA mismatch duplex formation with an association constant K = 3.9 × 10⁵M⁻¹. No direct evidence was acquired for hairpin formation in any instance although its potential existence is considered possible for d(GCGAGC) on the basis of molecular modeling studies.
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Affiliation(s)
- Maxim P Evstigneev
- Sevastopol National Technical University, Department of Physics, Sevastopol 99053, Ukraine.
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38
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Neves MAD, Reinstein O, Johnson PE. Defining a stem length-dependent binding mechanism for the cocaine-binding aptamer. A combined NMR and calorimetry study. Biochemistry 2010; 49:8478-87. [PMID: 20735071 DOI: 10.1021/bi100952k] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have used a combined approach of NMR spectroscopy and isothermal titration calorimetry (ITC) to determine the ligand-binding mechanism employed by a cocaine-binding aptamer. We found that the length of the stem containing the 3' and 5' termini determines the nature of the binding mechanism. When this stem is six base pairs long, the secondary structure of the aptamer is fully folded in the free form and only putative tertiary interactions form with ligand binding. If this stem is shortened by three base pairs, the free form of the aptamer contains little secondary structure, and ligand binding triggers secondary structure formation and folding. This binding mechanism is supported by both NMR spectral changes and the ITC measured heat capacity of binding (ΔC(p)°). For the aptamer with the long stem the ΔC(p)° value is -557 ± 29 cal mol(-1) K(-1) and for the aptamer with the short stem the ΔC(p)° value is -922 ± 51 cal mol(-1) K(-1). Chemical shift perturbation data and the observation of intermolecular NOEs indicate that the three-way junction is the site of ligand binding.
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Affiliation(s)
- Miguel A D Neves
- Department of Chemistry, York University, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3
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39
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Školáková P, Bednářová K, Vorlíčková M, Sagi J. Quadruplexes of human telomere dG3(TTAG3)3 sequences containing guanine abasic sites. Biochem Biophys Res Commun 2010; 399:203-8. [DOI: 10.1016/j.bbrc.2010.07.055] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2010] [Accepted: 07/15/2010] [Indexed: 12/20/2022]
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40
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Huang RH, Fremont DH, Diener JL, Schaub RG, Sadler JE. A structural explanation for the antithrombotic activity of ARC1172, a DNA aptamer that binds von Willebrand factor domain A1. Structure 2010; 17:1476-84. [PMID: 19913482 DOI: 10.1016/j.str.2009.09.011] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2009] [Revised: 09/08/2009] [Accepted: 09/13/2009] [Indexed: 11/15/2022]
Abstract
ARC1172 is a 41-mer DNA aptamer selected to bind the A1 domain of von Willebrand factor (VWF). A derivative of ARC1172 with modifications to increase intravascular survival inhibits carotid artery thrombosis in a Cynomolgus macaque model and inhibits VWF-dependent platelet aggregation in humans, suggesting that such aptamers may be useful to prevent or treat thrombosis. In the crystal structure of a VWF A1-ARC1172 complex, the aptamer adopts a three-stem structure of mainly B-form DNA with three noncanonical base pairs and 9 unpaired residues, 6 of which are stabilized by base-base or base-deoxyribose stacking interactions. The aptamer-protein interface is characterized by cation-pi interactions involving Arg, Lys, and Gln residues, often stabilized by H-bonds with adjacent bases. The ARC1172 binding site on the A1 domain overlaps with that of botrocetin and clashes with glycoprotein Ibalpha binding at an adjacent site, which accounts for the antithrombotic activity of ARC1172 and related aptamers.
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Affiliation(s)
- Ren-Huai Huang
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
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41
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Orava EW, Cicmil N, Gariépy J. Delivering cargoes into cancer cells using DNA aptamers targeting internalized surface portals. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:2190-200. [PMID: 20144587 DOI: 10.1016/j.bbamem.2010.02.004] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Accepted: 02/03/2010] [Indexed: 11/18/2022]
Abstract
Many evolving treatments for cancer patients are based on the targeted delivery of therapeutic cargoes to and into cancer cells. The advent of monoclonal antibodies and the use of peptide hormones, growth factors and cytokines have historically provided a spectrum of ligands needed to selectively target tumor-associated antigens on cancer cells. However, issues linked to the size, cost and immunogenicity of protein-based ligands have led to the search for alternate ligand families. The advent of short synthetic oligonucleotide ligands known as aptamers now provides a simple strategy to select for membrane-impermeant aptamers tailored to precisely target internalized surface markers present on cancer cells. Here we described how 25-base long, synthetic single-stranded DNA aptamers were derived to bind to known internalized tumor markers such as CD33, CEA, MUC1 and Tn antigens and are imported through these surface portals into cancer cells. The key consequence of using internalized aptamers is their ability to accumulate inside the cells, thus routing their therapeutic cargoes to intracellular sites relevant to their action. Internalized aptamers are discussed in the context of how such ligands have been used to create a range of guided therapeutic agents ranging from drug-based conjugates up to targeted nanoparticles.
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Affiliation(s)
- Erik W Orava
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario, Canada
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42
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Zhao J, Bacolla A, Wang G, Vasquez KM. Non-B DNA structure-induced genetic instability and evolution. Cell Mol Life Sci 2010; 67:43-62. [PMID: 19727556 PMCID: PMC3017512 DOI: 10.1007/s00018-009-0131-2] [Citation(s) in RCA: 310] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Revised: 07/22/2009] [Accepted: 08/11/2009] [Indexed: 11/26/2022]
Abstract
Repetitive DNA motifs are abundant in the genomes of various species and have the capacity to adopt non-canonical (i.e., non-B) DNA structures. Several non-B DNA structures, including cruciforms, slipped structures, triplexes, G-quadruplexes, and Z-DNA, have been shown to cause mutations, such as deletions, expansions, and translocations in both prokaryotes and eukaryotes. Their distributions in genomes are not random and often co-localize with sites of chromosomal breakage associated with genetic diseases. Current genome-wide sequence analyses suggest that the genomic instabilities induced by non-B DNA structure-forming sequences not only result in predisposition to disease, but also contribute to rapid evolutionary changes, particularly in genes associated with development and regulatory functions. In this review, we describe the occurrence of non-B DNA-forming sequences in various species, the classes of genes enriched in non-B DNA-forming sequences, and recent mechanistic studies on DNA structure-induced genomic instability to highlight their importance in genomes.
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Affiliation(s)
- Junhua Zhao
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M.D. Anderson Cancer Center, 1808 Park Road 1-C, P.O. Box 389, Smithville, TX 78957 USA
| | - Albino Bacolla
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M.D. Anderson Cancer Center, 1808 Park Road 1-C, P.O. Box 389, Smithville, TX 78957 USA
| | - Guliang Wang
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M.D. Anderson Cancer Center, 1808 Park Road 1-C, P.O. Box 389, Smithville, TX 78957 USA
| | - Karen M. Vasquez
- Department of Carcinogenesis, Science Park-Research Division, The University of Texas M.D. Anderson Cancer Center, 1808 Park Road 1-C, P.O. Box 389, Smithville, TX 78957 USA
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43
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Base flipping in V(D)J recombination: insights into the mechanism of hairpin formation, the 12/23 rule, and the coordination of double-strand breaks. Mol Cell Biol 2009; 29:5889-99. [PMID: 19720743 DOI: 10.1128/mcb.00187-09] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Tn5 transposase cleaves the transposon end using a hairpin intermediate on the transposon end. This involves a flipped base that is stacked against a tryptophan residue in the protein. However, many other members of the cut-and-paste transposase family, including the RAG1 protein, produce a hairpin on the flanking DNA. We have investigated the reversed polarity of the reaction for RAG recombination. Although the RAG proteins appear to employ a base-flipping mechanism using aromatic residues, the putatively flipped base is not at the expected location and does not appear to stack against any of the said aromatic residues. We propose an alternative model in which a flipped base is accommodated in a nonspecific pocket or cleft within the recombinase. This is consistent with the location of the flipped base at position -1 in the coding flank, which can be occupied by purine or pyrimidine bases that would be difficult to stabilize using a single, highly specific, interaction. Finally, during this work we noticed that the putative base-flipping events on either side of the 12/23 recombination signal sequence paired complex are coupled to the nicking steps and serve to coordinate the double-strand breaks on either side of the complex.
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Dextraze ME, Cecchini S, Bergeron F, Girouard S, Turcotte K, Wagner JR, Hunting DJ. Reaching for the other side: generating sequence-dependent interstrand cross-links with 5-bromodeoxyuridine and gamma-rays. Biochemistry 2009; 48:2005-11. [PMID: 19216505 DOI: 10.1021/bi801684t] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Interstrand cross-links impede critical cellular processes such as transcription and replication and are thus considered to be one of the most toxic types of DNA damage. Although several studies now point to the existence of gamma-radiation-induced cross-links in cellular DNA, little is known about the characteristics required for their creation. Recently, we reported the formation of interstrand cross-links that were specific for mismatched nucleotides within 5-bromo-2'-deoxyuridine-substituted DNA. Given the structural specificity for interstrand cross-link formation, it is likely that open or mismatched regions of DNA in cells may be particularly favorable for cross-link production. Herein, we investigated the effect of the local DNA sequence on the formation of interstrand cross-links, using 5-bromo-2'-deoxyuridine to generate radicals in a mismatched region of DNA. We investigated a total of 12 variations of bases in the mismatched region. The oligonucleotides were irradiated with gamma-rays, and interstrand cross-link formation was analyzed by denaturing gel electrophoresis. We found that the efficiency of cross-link formation was highly dependent on the nature of mismatched bases and, on the basis of electrophoretic mobility, observed several distinctive cross-link structures with specific DNA sequences. This study provides new insights into the reactivity of mismatched DNA and the mechanisms leading to interstrand cross-link formation. The potential application of 5-bromo-2'-deoxyuridine-induced interstrand cross-links to the field of DNA repair is discussed.
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Affiliation(s)
- Marie-Eve Dextraze
- Center for Research in Radiotherapy (CR2), Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Sciences, Universite de Sherbrooke, Sherbrooke, Quebec, Canada J1H 5N4
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45
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Santini GPH, Cognet JAH, Xu D, Singarapu KK, Hervé du Penhoat C. Nucleic acid folding determined by mesoscale modeling and NMR spectroscopy: solution structure of d(GCGAAAGC). J Phys Chem B 2009; 113:6881-93. [PMID: 19374420 DOI: 10.1021/jp8100656] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Determination of DNA solution structure is a difficult task even with the high-sensitivity method used here based on simulated annealing with 35 restraints/residue (Cryoprobe 750 MHz NMR). The conformations of both the phosphodiester linkages and the dinucleotide segment encompassing the sharp turn in single-stranded DNA are often underdetermined. To obtain higher quality structures of a DNA GNRA loop, 5'-d(GCGAAAGC)-3', we have used a mesoscopic molecular modeling approach, called Biopolymer Chain Elasticity (BCE), to provide reference conformations. By construction, these models are the least deformed hairpin loop conformation derived from canonical B-DNA at the nucleotide level. We have further explored this molecular conformation at the torsion angle level with AMBER molecular mechanics using different possible (epsilon,zeta) constraints to interpret the 31P NMR data. This combined approach yields a more accurate molecular conformation, compatible with all the NMR data, than each method taken separately, NMR/DYANA or BCE/AMBER. In agreement with the principle of minimal deformation of the backbone, the hairpin motif is stabilized by maximal base-stacking interactions on both the 5'- and 3'-sides and by a sheared G.A mismatch base pair between the first and last loop nucleotides. The sharp turn is located between the third and fourth loop nucleotides, and only two torsion angles beta6 and gamma6 deviate strongly with respect to canonical B-DNA structure. Two other torsion angle pairs epsilon3,zeta3 and epsilon5,zeta5 exhibit the newly recognized stable conformation BIIzeta+ (-70 degrees, 140 degrees). This combined approach has proven to be useful for the interpretation of an unusual 31P chemical shift in the 5'-d(GCGAAAGC)-3' hairpin.
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Affiliation(s)
- Guillaume P H Santini
- Laboratoire de Biophysique Moleculaire, Cellulaire et Tissulaire, UMR 7033 CNRS, Universite Pierre et Marie Curie Paris 6, Genopole Campus 1, 5 rue Henri Desbrueres, Evry 91030, France
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46
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Alemayehu S, Fish DJ, Brewood GP, Horne MT, Manyanga F, Dickman R, Yates I, Benight AS. Influence of Buffer Species on the Thermodynamics of Short DNA Duplex Melting: Sodium Phosphate versus Sodium Cacodylate. J Phys Chem B 2009; 113:2578-86. [DOI: 10.1021/jp809310w] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Saba Alemayehu
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Daniel J. Fish
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Greg P. Brewood
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - M. Todd Horne
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Fidelis Manyanga
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Rebekah Dickman
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Ian Yates
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
| | - Albert S. Benight
- Portland Bioscience Inc., 2828 SW Corbett Ave., Suite 116, Portland, Oregon 97201, and Portland State University, Department of Chemistry, P.O. Box 751, Portland, Oregon 97207
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47
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Electron correlated ab initio study of amino group flexibility for improvement of molecular mechanics simulations on nucleic acid conformations and interactions. J Biol Phys 2008; 33:499-514. [PMID: 19669535 DOI: 10.1007/s10867-008-9091-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2007] [Accepted: 05/26/2008] [Indexed: 11/27/2022] Open
Abstract
High level ab initio studies demonstrate substantial conformational flexibility of amino groups of nucleic acid bases. This flexibility is important for biological functions of DNA. Existing force field models of molecular mechanics do not describe this phenomenon due to a lack of quantitative experimental data necessary for an adjustment of empirical parameters. We have performed extensive calculations of nucleic acid bases at the MP2/6-31G(d,p) level of ab initio theory for broad set of amino group configurations. Two-dimensional maps of energy and geometrical characteristics as functions of two amino hydrogen torsions have been constructed. We approximate the maps by polynomial expressions, which can be used in molecular mechanics calculations. Detailed considerations of these maps enable us to propose a method for determination of numerical coefficients in the developed formulae using restricted sets of points obtained via higher-level calculations.
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48
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Seela F, Budow S. Mismatch formation in solution and on DNA microarrays: how modified nucleosides can overcome shortcomings of imperfect hybridization caused by oligonucleotide composition and base pairing. MOLECULAR BIOSYSTEMS 2008; 4:232-45. [PMID: 18437266 DOI: 10.1039/b713259j] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The DNA microarray technology is a well-established and widely used technology although it has several drawbacks. The accurate molecular recognition of the canonical nucleobases of probe and target is the basis for reliable results obtained from microarray hybridization experiments. However, the great flexibility of base pairs within the DNA molecule allows the formation of various secondary structures incorporating Watson-Crick base pairs as well as non-canonical base pair motifs, thus becoming a source of inaccuracy and inconsistence. The first part of this report provides an overview of unusual base pair motifs formed during molecular DNA interaction in solution highlighting selected secondary structures employing non-Watson-Crick base pairs. The same mispairing phenomena obtained in solution are expected to occur for immobilized probe molecules as well as for target oligonucleotides employed in microarray hybridization experiments the effect of base pairing and oligonucleotide composition on hybridization is considered. The incorporation of nucleoside derivatives as close shape mimics of the four canonical nucleosides into the probe and target oligonucleotides is discussed as a chemical tool to resolve unwanted mispairing. The second part focuses non-Watson-Crick base pairing during hybridization performed on microarrays. This is exemplified for the unusual stable dG.dA base pair.
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Affiliation(s)
- Frank Seela
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany.
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49
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Brar SS, Sacho EJ, Tessmer I, Croteau DL, Erie DA, Diaz M. Activation-induced deaminase, AID, is catalytically active as a monomer on single-stranded DNA. DNA Repair (Amst) 2007; 7:77-87. [PMID: 17889624 PMCID: PMC2693009 DOI: 10.1016/j.dnarep.2007.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2007] [Revised: 08/03/2007] [Accepted: 08/04/2007] [Indexed: 11/18/2022]
Abstract
Hypermutation and class switch recombination of immunoglobulin genes are antigen-activated mechanisms triggered by AID, a cytidine deaminase. AID deaminates cytidine residues in the DNA of the variable and the switch regions of the immunoglobulin locus. The resulting uracil induces error-prone DNA synthesis in the case of hypermutation or DNA breaks that activate non-homologous recombination in the case of class switch recombination. In vitro studies have demonstrated that AID deaminates single-stranded but not double-stranded substrates unless AID is in a complex with RPA and the substrate is actively undergoing transcription. However, it is not clear whether AID deaminates its substrates primarily as a monomer or as a higher order oligomer. To examine the oligomerization state of AID alone and in the presence of single-stranded DNA substrates of various structures, including loops embedded in double-stranded DNA, we used atomic force microscopy (AFM) to visualize AID protein alone or in complex with DNA. Surprisingly, AFM results indicate that most AID molecules exist as a monomer and that it binds single-stranded DNA substrates as a monomer at concentrations where efficient deamination of single-stranded DNA substrates occur. The rate of deamination, under conditions of excess and limiting protein, also imply that AID can deaminate single-stranded substrates as a monomer. These results imply that non-phosphorylated AID is catalytically active as a monomer on single-stranded DNA in vitro, including single-stranded DNA found in loops similar to those transiently formed in the immunoglobulin switch regions during transcription.
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Affiliation(s)
- Sukhdev S. Brar
- Laboratory of Molecular Genetics, D3-01, National Institute of Environmental Health, Sciences/National Institutes of Health 111 TW Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Elizabeth J. Sacho
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Ingrid Tessmer
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Deborah L. Croteau
- Laboratory of Molecular Genetics, D3-01, National Institute of Environmental Health, Sciences/National Institutes of Health 111 TW Alexander Drive, Research Triangle Park, NC, 27709, USA
| | - Dorothy A. Erie
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Curriculum in Applied and Material Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Corresponding authors information: Dr. Marilyn Diaz, Tel. 919-541-4740, Fax, 919-541-7593, E-mail: or Dr. Dorothy Erie, Tel. 919-962-6370, Fax, 919-962-2388, E-mail:
| | - Marilyn Diaz
- Laboratory of Molecular Genetics, D3-01, National Institute of Environmental Health, Sciences/National Institutes of Health 111 TW Alexander Drive, Research Triangle Park, NC, 27709, USA
- Corresponding authors information: Dr. Marilyn Diaz, Tel. 919-541-4740, Fax, 919-541-7593, E-mail: or Dr. Dorothy Erie, Tel. 919-962-6370, Fax, 919-962-2388, E-mail:
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Aihara H, Huang WM, Ellenberger T. An interlocked dimer of the protelomerase TelK distorts DNA structure for the formation of hairpin telomeres. Mol Cell 2007; 27:901-13. [PMID: 17889664 PMCID: PMC2041798 DOI: 10.1016/j.molcel.2007.07.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 06/11/2007] [Accepted: 07/25/2007] [Indexed: 12/27/2022]
Abstract
The termini of linear chromosomes are protected by specialized DNA structures known as telomeres that also facilitate the complete replication of DNA ends. The simplest type of telomere is a covalently closed DNA hairpin structure found in linear chromosomes of prokaryotes and viruses. Bidirectional replication of a chromosome with hairpin telomeres produces a catenated circular dimer that is subsequently resolved into unit-length chromosomes by a dedicated DNA cleavage-rejoining enzyme known as a hairpin telomere resolvase (protelomerase). Here we report a crystal structure of the protelomerase TelK from Klebsiella oxytoca phage varphiKO2, in complex with the palindromic target DNA. The structure shows the TelK dimer destabilizes base pairing interactions to promote the refolding of cleaved DNA ends into two hairpin ends. We propose that the hairpinning reaction is made effectively irreversible by a unique protein-induced distortion of the DNA substrate that prevents religation of the cleaved DNA substrate.
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Affiliation(s)
- Hideki Aihara
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, 660 S. Euclid Ave., Campus Box 8231, St. Louis, MO 63110
| | - Wai Mun Huang
- Department of Pathology, EEJ Medical Research Building, Room 5200B 15 N. Medical Dr. East, University of Utah Health Sciences Center, Salt Lake City, Utah 84112
| | - Tom Ellenberger
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, 660 S. Euclid Ave., Campus Box 8231, St. Louis, MO 63110
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