1
|
Palafox MA, Pedraza Velasco MLD, Marín JI, Posada-Moreno P. How proton transfer affects the helical parameters in DNA:DNA microhelices. J Biomol Struct Dyn 2022; 40:13759-13777. [PMID: 34806548 DOI: 10.1080/07391102.2021.1994880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Proton transfer reactions are a widespread phenomenon in many areas of the life sciences and it is one of the origins of the spontaneous point mutations during DNA replication. Because of its importance, many studies have been reported on these reactions. However, the present work is the first one focused on the structural geometrical changes by double proton transfer (DPT). Thus, different Watson-Crick (WC) pairs were optimized first in a simple model with one nucleoside base pair, and in a microhelix form with three nucleoside base pairs. The canonical and few tautomeric forms were considered in DNA:DNA microhelices with A-type and B-type helical forms. The stability of these structures and how the DPT process affects the main geometrical parameters was analyzed, in particular the deformation of the helical parameters. The M06-2X DFT method was used for this purpose. The purine/pyrimidine ring in the keto form appears easier to be deformed than when it is in the enol form. The weaker WC base pair formed with mixed microhelices than with nucleobases alone and the significant deformation of the helical and backbone parameters with the DPT appears to complicate this process in microhelices.Communicated by Ramaswamy H. Sarma.
Collapse
Affiliation(s)
- Mauricio Alcolea Palafox
- Departamento de Química-Fisica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid. Ciudad Universitaria s/n, Madrid, Spain
| | | | - Josefa Isasi Marín
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, Madrid, Spain
| | - Paloma Posada-Moreno
- Departamento de Enfermería, Facultad de Enfermería, Fisioterapia y Podología, Universidad Complutense de Madrid, Madrid, Spain.,Departamento de Enfermería, UCM, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| |
Collapse
|
2
|
Maity A, Winnerdy FR, Chen G, Phan AT. Duplexes Formed by G 4C 2 Repeats Contain Alternate Slow- and Fast-Flipping G·G Base Pairs. Biochemistry 2021; 60:1097-1107. [PMID: 33750098 DOI: 10.1021/acs.biochem.0c00916] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Aberrant expansion of the hexanucleotide GGGGCC (or G4C2) repeat in the human C9ORF72 gene is the most common genetic factor found behind amyotrophic lateral sclerosis and frontotemporal dementia. The hypothesized pathways, through which the repeat expansions contribute to the pathology, involve one or more secondary structural forms of the DNA and/or RNA sequences, such as G-quadruplexes, duplexes, and hairpins. Here, we study the structures of DNA and RNA duplexes formed by G4C2 repeats, which contain G(syn)·G(anti) base pairs flanked by either G·C or C·G base pairs. We show that duplexes formed by G4C2 repeats contain alternately two types of G·G pair contexts exhibiting different syn-anti base flipping dynamics (∼100 ms vs ∼2 ms for DNA and ∼50 ms vs ∼20 ms for RNA at 10 °C, respectively) depending on the flanking bases, with the slow-flipping G·G pairs being flanked by a guanine at the 5'-end and the fast-flipping G·G pairs being flanked by a cytosine at the 5'-end. Our findings on the structures and dynamics of G·G base pairs in DNA and RNA duplexes formed by G4C2 repeats provide a foundation for further studies of the functions and targeting of such biologically relevant motifs.
Collapse
Affiliation(s)
- Arijit Maity
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
| | - Gang Chen
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,School of Life and Health Sciences, The Chinese University of Hong Kong, Shenzhen (CUHK-Shenzhen), No. 2001 Longxiang Boulevard, Longgang District, Shenzhen, Guangdong 518172, P. R. China
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.,NTU Institute of Structural Biology, Nanyang Technological University, Singapore 636921, Singapore
| |
Collapse
|
3
|
Oliveira LM, Long AS, Brown T, Fox KR, Weber G. Melting temperature measurement and mesoscopic evaluation of single, double and triple DNA mismatches. Chem Sci 2020; 11:8273-8287. [PMID: 34094181 PMCID: PMC8163305 DOI: 10.1039/d0sc01700k] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Unlike the canonical base pairs AT and GC, the molecular properties of mismatches such as hydrogen bonding and stacking interactions are strongly dependent on the identity of the neighbouring base pairs. As a result, due to the sheer number of possible combinations of mismatches and flanking base pairs, only a fraction of these have been studied in varying experiments or theoretical models. Here, we report on the melting temperature measurement and mesoscopic analysis of contiguous DNA mismatches in nearest-neighbours and next-nearest neighbour contexts. A total of 4032 different mismatch combinations, including single, double and triple mismatches were covered. These were compared with 64 sequences containing all combinations of canonical base pairs in the same location under the same conditions. For a substantial number of single mismatch configurations, 15%, the measured melting temperatures were higher than the least stable AT base pair. The mesoscopic calculation, using the Peyrard-Bishop model, was performed on the set of 4096 sequences, and resulted in estimates of on-site and nearest-neighbour interactions that can be correlated to hydrogen bonding and base stacking. Our results confirm many of the known properties of mismatches, including the peculiar sheared stacking of tandem GA mismatches. More intriguingly, it also reveals that a number of mismatches present strong hydrogen bonding when flanked on both sites by other mismatches. To highlight the applicability of our results, we discuss a number of practical situations such as enzyme binding affinities, thymine DNA glycosylase repair activity, and trinucleotide repeat expansions.
Collapse
Affiliation(s)
- Luciana M Oliveira
- Departamento de Física, Universidade Federal de Minas Gerais 31270-901 Belo Horizonte MG Brazil +55 31 3409 5600 +55 31 3409 6616
| | - Adam S Long
- School of Biological Sciences, University of Southampton Life Sciences Building 85 Southampton SO17 1BJ UK
| | - Tom Brown
- Department of Chemistry, University of Oxford Oxford UK
| | - Keith R Fox
- School of Biological Sciences, University of Southampton Life Sciences Building 85 Southampton SO17 1BJ UK
| | - Gerald Weber
- Departamento de Física, Universidade Federal de Minas Gerais 31270-901 Belo Horizonte MG Brazil +55 31 3409 5600 +55 31 3409 6616
| |
Collapse
|
4
|
Satange R, Chuang CY, Neidle S, Hou MH. Polymorphic G:G mismatches act as hotspots for inducing right-handed Z DNA by DNA intercalation. Nucleic Acids Res 2019; 47:8899-8912. [PMID: 31361900 PMCID: PMC6895262 DOI: 10.1093/nar/gkz653] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/06/2019] [Accepted: 07/17/2019] [Indexed: 12/13/2022] Open
Abstract
DNA mismatches are highly polymorphic and dynamic in nature, albeit poorly characterized structurally. We utilized the antitumour antibiotic CoII(Chro)2 (Chro = chromomycin A3) to stabilize the palindromic duplex d(TTGGCGAA) DNA with two G:G mismatches, allowing X-ray crystallography-based monitoring of mismatch polymorphism. For the first time, the unusual geometry of several G:G mismatches including syn–syn, water mediated anti–syn and syn–syn-like conformations can be simultaneously observed in the crystal structure. The G:G mismatch sites of the d(TTGGCGAA) duplex can also act as a hotspot for the formation of alternative DNA structures with a GC/GA-5′ intercalation site for binding by the GC-selective intercalator actinomycin D (ActiD). Direct intercalation of two ActiD molecules to G:G mismatch sites causes DNA rearrangements, resulting in backbone distortion to form right-handed Z-DNA structures with a single-step sharp kink. Our study provides insights on intercalators-mismatch DNA interactions and a rationale for mismatch interrogation and detection via DNA intercalation.
Collapse
Affiliation(s)
- Roshan Satange
- Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung, 402, Taiwan.,Ph.D. Program in Medical Biotechnology, National Chung Hsing University, Taichung, 402, Taiwan
| | - Chien-Ying Chuang
- Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung, 402, Taiwan
| | - Stephen Neidle
- The School of Pharmacy, University College London, London, WC1N 1AX, UK
| | - Ming-Hon Hou
- Institute of Genomics and Bioinformatics, National Chung Hsing University, Taichung, 402, Taiwan.,Ph.D. Program in Medical Biotechnology, National Chung Hsing University, Taichung, 402, Taiwan.,Department of Life Sciences, National Chung Hsing University, Taichung, 402, Taiwan
| |
Collapse
|
5
|
Rangadurai A, Zhou H, Merriman DK, Meiser N, Liu B, Shi H, Szymanski ES, Al-Hashimi HM. Why are Hoogsteen base pairs energetically disfavored in A-RNA compared to B-DNA? Nucleic Acids Res 2019; 46:11099-11114. [PMID: 30285154 PMCID: PMC6237737 DOI: 10.1093/nar/gky885] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 10/02/2018] [Indexed: 12/15/2022] Open
Abstract
A(syn)-U/T and G(syn)-C+ Hoogsteen (HG) base pairs (bps) are energetically more disfavored relative to Watson–Crick (WC) bps in A-RNA as compared to B-DNA by >1 kcal/mol for reasons that are not fully understood. Here, we used NMR spectroscopy, optical melting experiments, molecular dynamics simulations and modified nucleotides to identify factors that contribute to this destabilization of HG bps in A-RNA. Removing the 2′-hydroxyl at single purine nucleotides in A-RNA duplexes did not stabilize HG bps relative to WC. In contrast, loosening the A-form geometry using a bulge in A-RNA reduced the energy cost of forming HG bps at the flanking sites to B-DNA levels. A structural and thermodynamic analysis of purine-purine HG mismatches reveals that compared to B-DNA, the A-form geometry disfavors syn purines by 1.5–4 kcal/mol due to sugar-backbone rearrangements needed to sterically accommodate the syn base. Based on MD simulations, an additional penalty of 3–4 kcal/mol applies for purine-pyrimidine HG bps due to the higher energetic cost associated with moving the bases to form hydrogen bonds in A-RNA versus B-DNA. These results provide insights into a fundamental difference between A-RNA and B-DNA duplexes with important implications for how they respond to damage and post-transcriptional modifications.
Collapse
Affiliation(s)
- Atul Rangadurai
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | - Huiqing Zhou
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | | | - Nathalie Meiser
- Goethe University, Institute for Organic Chemistry and Chemical Biology, Frankfurt am Main, Germany
| | - Bei Liu
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | - Honglue Shi
- Department of Chemistry, Duke University, Durham, NC, USA
| | - Eric S Szymanski
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA
| | - Hashim M Al-Hashimi
- Department of Biochemistry, Duke University School of Medicine, Durham, NC, USA.,Department of Chemistry, Duke University, Durham, NC, USA
| |
Collapse
|
6
|
Teng Y, Pramanik S, Tateishi-Karimata H, Ohyama T, Sugimoto N. Drastic stability change of X-X mismatch in d(CXG) trinucleotide repeat disorders under molecular crowding condition. Biochem Biophys Res Commun 2018; 496:601-607. [PMID: 29339157 DOI: 10.1016/j.bbrc.2018.01.083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 12/28/2017] [Accepted: 01/11/2018] [Indexed: 10/18/2022]
Abstract
The trinucleotide repeat d(CXG) (X = A, C, G or T) is the most common sequence causing repeat expansion disorders. The formation of non-canonical structures, such as hairpin structures with X-X mismatches, has been proposed to affect gene expression and regulation, which are important in pathological studies of these devastating neurological diseases. However, little information is available regarding the thermodynamics of the repeat sequence under crowded cellular conditions where many non-canonical structures such as G-quadruplexes are highly stabilized, while duplexes are destabilised. In this study, we investigated the different stabilities of X-X mismatches in the context of internal d(CXG) self-complementary sequences in an environment with a high concentration of cosolutes to mimic the crowding conditions in cells. The stabilities of full-matched duplexes and duplexes with A-A, G-G, and T-T mismatched base pairs under molecular crowding conditions were notably decreased compared to under dilute conditions. However, the stability of the DNA duplex with a C-C mismatch base pair was only slightly destabilised. Investigating different stabilities of X-X mismatches in d(CXG) sequences is important for improving our understanding of the formation and transition of multiple non-canonical structures in trinucleotide repeat diseases, and may provide insights for pathological studies and drug development.
Collapse
Affiliation(s)
- Ye Teng
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan
| | - Smritimoy Pramanik
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan; Department of Chemistry, University of Calcutta, 92 Acharya Prafulla Chandra Road, Kolkata, 700009, India
| | - Hisae Tateishi-Karimata
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Chuo-ku, Kobe, 650-0047, Japan
| | - Tatsuya Ohyama
- Frontier Institute for Biomolecular Engineering Research (FIBER), 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.
| |
Collapse
|
7
|
Brovarets’ OO, Hovorun DM. Does the G·G*synDNA mismatch containing canonical and rare tautomers of the guanine tautomerise through the DPT? A QM/QTAIM microstructural study. Mol Phys 2014. [DOI: 10.1080/00268976.2014.927079] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
8
|
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]
|
9
|
Impact of conformational heterogeneity of OxoG lesions and their pairing partners on bypass fidelity by Y family polymerases. Structure 2009; 17:725-36. [PMID: 19446528 DOI: 10.1016/j.str.2009.03.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 03/06/2009] [Accepted: 03/09/2009] [Indexed: 11/22/2022]
Abstract
7,8-Dihydro-8-oxoguanine (oxoG), the predominant oxidative DNA damage lesion, is processed differently by high-fidelity and Y-family lesion bypass polymerases. Although high-fidelity polymerases extend predominantly from an A base opposite an oxoG, the Y-family polymerases Dpo4 and human Pol eta preferentially extend from the oxoG*C base pair. We have determined crystal structures of extension Dpo4 ternary complexes with oxoG opposite C, A, G, or T and the next nascent base pair. We demonstrate that neither template backbone nor the architecture of the active site is perturbed by the oxoG(anti)*C and oxoG*A pairs. However, the latter manifest conformational heterogeneity, adopting both oxoG(syn)*A(anti) and oxoG(anti)*A(syn) alignment. Hence, the observed reduced primer extension from the dynamically flexible 3'-terminal primer base A is explained. Because of homology between Dpo4 and Pol eta, such a dynamic screening mechanism might be utilized by Dpo4 and Pol eta to regulate error-free versus error-prone bypass of oxoG and other lesions.
Collapse
|
10
|
DeCarlo L, Gowda ASP, Suo Z, Spratt TE. Formation of purine-purine mispairs by Sulfolobus solfataricus DNA polymerase IV. Biochemistry 2008; 47:8157-64. [PMID: 18616289 DOI: 10.1021/bi800820m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
DNA damage that stalls replicative polymerases can be bypassed with the Y-family polymerases. These polymerases have more open active sites that can accommodate modified nucleotides. The lack of protein-DNA interactions that select for Watson-Crick base pairs correlate with the lowered fidelity of replication. Interstrand hydrogen bonds appear to play a larger role in dNTP selectivity. The mechanism by which purine-purine mispairs are formed and extended was examined with Solfolobus solfataricus DNA polymerase IV, a member of the RAD30A subfamily of the Y-family polymerases, as is pol eta. The structures of the purine-purine mispairs were examined by comparing the kinetics of mispair formation with adenine versus 1-deaza- and 7-deazaadenine and guanine versus 7-deazaguanine at four positions in the DNA, the incoming dNTP, the template base, and both positions of the terminal base pair. The time course of insertion of a single dNTP was examined with a polymerase concentration of 50 nM and a DNA concentration of 25 nM with various concentrations of dNTP. The time courses were fitted to a first-order equation, and the first-order rate constants were plotted against the dNTP concentration to produce k pol and K d (dNTP) values. A decrease in k pol/ K d (dNTP) associated with the deazapurine substitution would indicate that the position is involved in a crucial hydrogen bond. During correct base pair formation, the adenine to 1-deazaadenine substitution in both the incoming dNTP and template base resulted in a >1000-fold decrease in k pol/ K d (dNTP), indicating that interstrand hydrogen bonds are important in correcting base pair formation. During formation of purine-purine mispairs, the k pol/ K d (dNTP) values for the insertion of dATP and dGTP opposite 7-deazaadenine and 7-deazaguanine were decreased >10-fold with respect to those of the unmodified nucleotides. In addition, the rate of incorporation of 1-deaza-dATP opposite guanine was decreased 5-fold. These results suggest that during mispair formation the newly forming base pair is in a Hoogsteen geometry with the incoming dNTP in the anti conformation and the template base in the syn conformation. These results indicate that Dpo4 holds the incoming dNTP in the normal anti conformation while allowing the template nucleotide to change conformations to allow reaction to occur. This result may be functionally relevant in the replication of damaged DNA in that the polymerase may allow the template to adopt multiple configurations.
Collapse
Affiliation(s)
- Lindsey DeCarlo
- Department of Biochemistry and Molecular Biology, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
| | | | | | | |
Collapse
|
11
|
Interactions of anticancer drugs with usual and mismatch base pairs — Density functional theory studies. Biophys Chem 2008; 136:50-8. [DOI: 10.1016/j.bpc.2008.04.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2008] [Revised: 04/22/2008] [Accepted: 04/22/2008] [Indexed: 01/18/2023]
|
12
|
Lane AN, Peck B. Conformational Flexibility in DNA Duplexes Containing Single G · G Mismatches. ACTA ACUST UNITED AC 2008. [DOI: 10.1111/j.1432-1033.1995.1073g.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
13
|
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.
Collapse
Affiliation(s)
- Frank Seela
- Laboratory of Bioorganic Chemistry and Chemical Biology, Center for Nanotechnology, Heisenbergstrasse 11, 48149 Münster, Germany.
| | | |
Collapse
|
14
|
Zenkova MA, Karpova GG. Imperfectly matched nucleic acid complexes and their biochemical manifestation. RUSSIAN CHEMICAL REVIEWS 2007. [DOI: 10.1070/rc1993v062n04abeh000023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
15
|
Kretulskie AM, Spratt TE. Structure of purine-purine mispairs during misincorporation and extension by Escherichia coli DNA polymerase I. Biochemistry 2006; 45:3740-6. [PMID: 16533057 DOI: 10.1021/bi052306u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The mechanism by which purine-purine mispairs are formed and extended was examined with the high-fidelity Klenow fragment of Escherichia coli DNA polymerase I with the proofreading exonuclease activity inactivated. The structures of the purine-purine mispairs were examined by comparing the kinetics of mispair formation with adenine versus 7-deazaadenine and guanine versus 7-deazaguanine at four positions in the DNA, the incoming dNTP, the template base, and both positions of the terminal base pair. A decrease in rate associated with a 7-deazapurine substitution would suggest that the nucleotide is in a syn conformation in a Hoogsteen base pair with the opposite base. During mispair formation, the k(pol)/K(d) values for the insertion of dATP opposite A (dATP/A) as well as dATP/G and dGTP/G were decreased greater than 10-fold with the deazapurine in the dNTP. These results suggest that during mispair formation the newly forming base pair is in a Hoogsteen geometry with the incoming dNTP in the syn conformation and the template base in the anti conformation. During mispair extension, the only decrease in k(pol)/K(d) was associated with the G/G base pair in which 7-deazaguanine was in the template strand. These results as well as previous results [McCain et al. (2005) Biochemistry 44, 5647-5659] in which a hydrogen bond was found between the 3-position of guanine at the primer terminus and Arg668 during G/A and G/G mispair extension indicate that the conformation of the purine at the primer terminus is in the anti conformation during mispair extension. These results suggest that purine-purine mispairs are formed via a Hoogsteen geometry in which the dNTP is in the syn conformation and the template is in the anti conformation. During extension, however, the conformation of the primer terminus changes to an anti configuration while the template base may be in either the syn or anti conformations.
Collapse
Affiliation(s)
- Angie M Kretulskie
- Department of Biochemistry and Molecular Biology, College of Medicine, The Pennsylvania State University, 500 University Drive, Hershey, Pennsylvania 17033, USA
| | | |
Collapse
|
16
|
Chen Z, Ji M, Hou P, Lu Z. Exo-Dye-based assay for rapid, inexpensive, and sensitive detection of DNA-binding proteins. Biochem Biophys Res Commun 2006; 345:1254-63. [PMID: 16716262 DOI: 10.1016/j.bbrc.2006.05.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Accepted: 05/02/2006] [Indexed: 10/24/2022]
Abstract
We reported herein a rapid, inexpensive, and sensitive technique for detecting sequence-specific DNA-binding proteins. In this technique, the common exonuclease III (ExoIII) footprinting assay is coupled with simple SYBR Green I staining for monitoring the activities of DNA-binding proteins. We named this technique as ExoIII-Dye-based assay. In this assay, a duplex probe was designed to detect DNA-binding protein. One side of the probe contains one protein-binding site, and another side of it contains five protruding bases at 3' end for protection from ExoIII digestion. If a target protein is present, it will bind to binding sites of probe and produce a physical hindrance to ExoIII, which protects the duplex probe from digestion of ExoIII. SYBR Green I will bind to probe, which results in high fluorescence intensity. On the contrary, in the absence of the target protein, the naked duplex probe will be degraded by ExoIII. SYBR Green I will be released, which results in a low fluorescence intensity. In this study, we employed this technique to successfully detect transcription factor NF-kappaB in crude cell extracts. Moreover, it could also be used to evaluate the binding affinity of NF-kappaB. This technique has therefore wide potential application in research, medical diagnosis, and drug discovery.
Collapse
Affiliation(s)
- Zaozao Chen
- Chien-Shiung Wu Laboratory, Department of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | | | | | | |
Collapse
|
17
|
Zhang RY, Wang XM, Gong SJ, He NY. Electrochemical detection of single a-g mismatch using biosensing surface based on gold nanoparticles. GENOMICS, PROTEOMICS & BIOINFORMATICS 2005; 3:47-51. [PMID: 16144522 PMCID: PMC5172468 DOI: 10.1016/s1672-0229(05)03007-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The study of small drug molecules interacting with nucleic acids is an area of intense research that has particular relevance in our understanding of relative mechanism in chemotherapeutic applications and the association between genetics (including sequence variation) and drug response. In this contribution, we demonstrate how the sequence-specific binding of an anticancer drug Dacarbazine (DTIC) to single base (A-G) mismatch could be sensitively detected by combining electrochemical detection with biosensing surface based on gold nanoparticles.
Collapse
Affiliation(s)
- Ren-Yun Zhang
- Chien-Shiung Wu Laboratory, National Lab of Molecular and Biomolecular Electronics, Department of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China.
| | | | | | | |
Collapse
|
18
|
Hou P, Ji M, He N, Lu Z. Microarray-based method to evaluate the accuracy of restriction endonucleases HpaII and MspI. Biochem Biophys Res Commun 2004; 314:110-7. [PMID: 14715253 DOI: 10.1016/j.bbrc.2003.12.063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A double-strand DNA (ds DNA) microarray was fabricated to analyze the structural perturbations caused by methylation and the different base mismatches in the interaction of the restriction endonucleases HpaII and MspI with DNA. First, a series of synthesized oligonucleotides were arrayed on the aldehyde-coated glass slides. Second, these oligonucleotides were hybridized with target sequences to obtain ds DNA microarray, which includes several types of double strands with the fully methylated, semi-methylated, and unmethylated canonical recognition sequences, semi-methylated and unmethylated base mismatches within the recognition sequences. The cleavage experiments were carried out under normal buffer conditions. The results indicated that MspI could partially cleave methylated and semi-methylated canonical recognition sequences. In contrast, HpaII could not cleave methylated and semi-methylated canonical recognition sequences. HpaII and MspI could both cleave the unmethylated canonical recognition sequence. However, HpaII could partially cleave the sequence containing one GG mismatch and not cleave other base mismatches in the corresponding recognition site. In contrast, MspI could not recognize the base mismatches within the recognition sequence. A good reproducibility was observed in several parallel experiments. The experiment indicates that the microarray technology has great potentials in high-throughput identifying important interactions between protein and DNA.
Collapse
Affiliation(s)
- Peng Hou
- Chien-Shiung Wu Laboratory, Department of Biological Science and Medical Engineering, Southeast University, Nanjing, China.
| | | | | | | |
Collapse
|
19
|
Thiviyanathan V, Somasunderam A, Hazra TK, Mitra S, Gorenstein DG. Solution structure of a DNA duplex containing 8-hydroxy-2'-deoxyguanosine opposite deoxyguanosine. J Mol Biol 2003; 325:433-42. [PMID: 12498794 DOI: 10.1016/s0022-2836(02)01272-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Deoxyguanosine residues are hydroxylated by reactive oxygen species at the C-8 position to form 8-hydroxy-2'-deoxyguanosine (8-OG), one of the most important mutagenic lesions in DNA. Though the spontaneous G:C to C:G transversions are rare events, the pathways leading to this mutation are not established. An 8-OG:G mispair, if not corrected by DNA repair enzymes, could lead to G:C to C:G transversions. NMR spectroscopy and restrained molecular dynamics calculations are used to refine the solution structure of the base mismatch formed by the 8-OG:G pair on a self complementary DNA dodecamer duplex d(CGCGAATT(8-O)GGCG)(2). The results reveal that the 8-OG base is inserted into the helix and forms Hoogsteen base-pairing with the G on the opposite strand. The 8-OG:G base-pairs are seen to be stabilized by two hydrogen bonding interactions, one between the H7 of the 8-OG and the O6 of the G, and a three-center hydrogen bonding between the O8 of the 8-OG and the imino and amino protons of the G. The 8-OG:G base-pairs are very well stacked between the Watson-Crick base-paired flanking bases. Both strands of the DNA duplex adopt right-handed conformations. All of the unmodified bases, including the G at the lesion site, adopt anti glycosidic torsion angles and form Watson-Crick base-pairs. At the lesion site, the 8-OG residues adopt syn conformations. The structural studies demonstrate that 8-OG(syn):G(anti) forms a stable pair in the interior of the duplex, providing a basis for the in vivo incorporation of G opposite 8-OG. Calculated helical parameters and backbone torsional angles, and the observed 31P chemical shifts, indicate that the structure of the duplex is perturbed near lesion sites, with the local unwinding of the double helix. The melting temperature of the 8-OG:G containing duplex is only 2.6 deg. C less than the t(m) of the unmodified duplex.
Collapse
Affiliation(s)
- Varatharasa Thiviyanathan
- Sealy Center for Structural Biology, Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555-1157, USA
| | | | | | | | | |
Collapse
|
20
|
Bhattacharya PK, Cha J, Barton JK. 1H NMR determination of base-pair lifetimes in oligonucleotides containing single base mismatches. Nucleic Acids Res 2002; 30:4740-50. [PMID: 12409465 PMCID: PMC135820 DOI: 10.1093/nar/gkf601] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Proton nuclear magnetic resonance (NMR) spectroscopy is employed to characterize the kinetics of base-pair opening in a series of 9mer duplexes containing different single base mismatches. The imino protons from the different mismatched, as well as fully matched, duplexes are assigned from the imino-imino region in the WATERGATE NOESY spectra. The exchange kinetics of the imino protons are measured from selective longitudinal relaxation times. In the limit of infinite exchange catalyst concentration, the exchange times of the mismatch imino protons extrapolate to much shorter lifetimes than are commonly observed for an isolated GC base pair. Different mismatches exhibit different orders of base-pair lifetimes, e.g. a TT mismatch has a shorter base-pair lifetime than a GG mismatch. The effect of the mismatch was observed up to a distance of two neighboring base pairs. This indicates that disruption in the duplex caused by the mismatch is quite localized. The overall order of base-pair lifetimes in the selected sequence context of the base pair is GC > GG > AA > CC > AT > TT. Interestingly, the fully matched AT base pair has a shorter base-pair lifetime relative to many of the mismatches. Thus, in any given base pair, the exchange lifetime can exhibit a strong dependence on sequence context. These findings may be relevant to the way mismatch recognition is accomplished by proteins and small molecules.
Collapse
Affiliation(s)
- Pratip K Bhattacharya
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | | | | |
Collapse
|
21
|
Foloppe N, Hartmann B, Nilsson L, MacKerell AD. Intrinsic conformational energetics associated with the glycosyl torsion in DNA: a quantum mechanical study. Biophys J 2002; 82:1554-69. [PMID: 11867468 PMCID: PMC1301954 DOI: 10.1016/s0006-3495(02)75507-0] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The glycosyl torsion (chi) in nucleic acids has long been recognized to be a major determinant of their conformational properties. chi torsional energetics were systematically mapped in deoxyribonucleosides using high-level quantum mechanical methods, for north and south sugar puckers and with gamma in the g(+) and trans conformations. In all cases, the syn conformation is found higher in energy than the anti. When gamma is changed from g(+) to trans, the anti orientation of the base is strongly destabilized, and the energy difference and barrier between anti and syn are significantly decreased. The barrier between anti and syn in deoxyribonucleosides is found to be less than 10 kcal/mol and tends to be lower with purines than with pyrimidines. With gamma = g(+)/chi = anti, a south sugar yields a significantly broader energy well than a north sugar with no energy barrier between chi values typical of A or B DNA. Contrary to the prevailing view, the syn orientation is not more stable with south puckers than with north puckers. The syn conformation is significantly more energetically accessible with guanine than with adenine in 5-nucleotides but not in nucleosides. Analysis of nucleic acid crystal structures shows that gamma = trans/chi = anti is a minor but not negligible conformation. Overall, chi appears to be a very malleable structural parameter with the experimental chi distributions reflecting, to a large extent, the associated intrinsic torsional energetics.
Collapse
Affiliation(s)
- Nicolas Foloppe
- Center for Structural Biology, Department of Bioscience, Karolinska Institutet, S-141 57, Huddinge, Sweden
| | | | | | | |
Collapse
|
22
|
Venkatarangan L, Sivaprasad A, Johnson F, Basu AK. Site-specifically located 8-amino-2'-deoxyguanosine: thermodynamic stability and mutagenic properties in Escherichia coli. Nucleic Acids Res 2001; 29:1458-63. [PMID: 11266546 PMCID: PMC31287 DOI: 10.1093/nar/29.7.1458] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2000] [Revised: 02/12/2001] [Accepted: 02/12/2001] [Indexed: 11/13/2022] Open
Abstract
2-Nitropropane (2-NP), an important industrial solvent and a component of cigarette smoke, is mutagenic in bacteria and carcinogenic in rats. 8-Amino-2'-deoxyguanosine (8-amino-dG) is one of the types of DNA damage found in liver, the target organ in 2-NP-treated rats. To investigate the thermodynamic properties of 8-amino-dG opposite each of the four DNA bases, we have synthesized an 11mer, d(CCATCG*CTACC), in which G* represents the modified base. By annealing a complementary DNA strand to this modified 11mer, four sets of duplexes were generated each containing one of the four DNA bases opposite the lesion. Circular dichroism studies indicated that 8-amino-dG did not alter the global helical properties of natural right-handed B-DNA. The thermal stability of each duplex was examined by UV melting measurements and compared with its unmodified counterpart. For the unmodified 11mer, the relative stability of the complementary DNA bases opposite G was in the order C > T > G > A, as determined from their -DeltaG degrees values. The free energy change of each modified duplex was lower than its unmodified counterpart, except for the G*:G pair that exhibited a higher melting transition and a larger -DeltaG degrees than the G:G duplex. Nevertheless, the stability of the modified 11mer duplex also followed the order C > T > G > A when placed opposite 8-amino-dG. To explore if 8-amino-dG opposite another 8-amino-dG has any advantage in base pairing, a G*:G* duplex was evaluated, which showed that the stability of this duplex was similar to the G*:G duplex. Mutagenesis of 8-amino-dG in this sequence context was studied in Escherichia coli, which showed that the lesion is weakly mutagenic (mutation frequency approximately 10(-3)) but still can induce a variety of targeted and semi-targeted mutations.
Collapse
Affiliation(s)
- L Venkatarangan
- Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
| | | | | | | |
Collapse
|
23
|
Mariappan SV, Silks LA, Chen X, Springer PA, Wu R, Moyzis RK, Bradbury EM, Garcia AE, Gupta G. Solution structures of the Huntington's disease DNA triplets, (CAG)n. J Biomol Struct Dyn 1998; 15:723-44. [PMID: 9514249 DOI: 10.1080/07391102.1998.10508988] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Highly polymorphic DNA triplet repeats, (CAG)n, are located inside the first exon of the Huntington's disease gene. Inordinate expansion of this repeat is correlated with the onset and progression of the disease. NMR spectroscopy, gel electrophoresis, digestion by single-strand specific P1 enzyme, and in vitro replication assay have been used to investigate the structural basis of (CAG)n expansion. Nondenaturing gel electrophoresis and 1D 1H NMR studies of (CAG)5 and (CAG)6 reveal the presence of hairpins and mismatched duplexes as the major and minor populations respectively. However, at high DNA concentrations (i.e., 1.0-2.0 mM that is typically required for 2D NMR experiments) both (CAG)5 and (CAG)6 exist predominantly in mismatched duplex forms. Mismatched duplex structures of (CAG)5 and (CAG)6 are useful, because they adequately model the stem of the biologically relevant hairpins formed by (CAG)n. We, therefore, performed detailed NMR spectroscopic studies on the duplexes of (CAG)5 and (CAG)6. We also studied a model duplex, (CGCAGCG)2 that contains the underlined building block of the duplex. This duplex shows the following structural characteristics: (i) all the nucleotides are in (C2'-endo, anti) conformations, (ii) mismatched A x A base pairs are flanked by two Watson-Crick G x C base pairs and (iii) A x A base pairs are stably stacked (and intra-helical) and are formed by a single N6-H--N1 hydrogen bond. The nature of A x A pairing is confirmed by temperature-dependent HMQC and HMQC-NOESY experiments on the [(CA*G)5]2 duplex where the adenines are 15N-labeled at N6. Temperature- and pH-dependent imino proton spectra, nondenaturing electrophoresis, and P1 digestion data demonstrate that under a wide range of solution conditions longer (CAG)n repeats (n> or =10) exist exclusively in hairpin conformation with two single-stranded loops. Finally, an in vitro replication assay with (CAG)8,21 inserts in the M13 single-stranded DNA templates shows a replication bypass for the (CAG)21 insert but not for the (CAG)8 insert in the template. This demonstrates that for a sufficiently long insert (n=21 in this case), a hairpin is formed by the (CAG)n even in presence of its complementary strand. This observation implies that the formation of hairpin by the (CAG)n may cause slippage during replication and thus may explain the observed length polymorphism.
Collapse
Affiliation(s)
- S V Mariappan
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, NM 87545, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Boulard Y, Cognet JA, Fazakerley GV. Solution structure as a function of pH of two central mismatches, C . T and C . C, in the 29 to 39 K-ras gene sequence, by nuclear magnetic resonance and molecular dynamics. J Mol Biol 1997; 268:331-47. [PMID: 9159474 DOI: 10.1006/jmbi.1997.0975] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The DNA duplexes 5' d(GCCACCAGCTC) x d(GAGCTXGTGGC), where the base X is either cytosine or thymine, have been studied by one and two-dimensional nuclear magnetic resonance, energy minimization and molecular dynamics. The sequence studied corresponds to the region 29 to 39 of the K-ras gene and is a hot spot for mutations. The results show that both duplexes adopt a globally B-DNA-type structure. For the C x C mismatch, we observe a structural change as a function of pH with an apparent pK of 6.95. The neutral species has only one hydrogen bond between the two bases but shows two families of wobble structures where one base or the other is displaced in the major groove. The protonated species has two hydrogen bonds and two structures but of unequal populations. In both systems, the sugar puckers remain predominantly C2'-endo and no significant changes in the backbone structure are observed. The neutral C . T mismatch is stabilized by two hydrogen bonds but, surprisingly, it can also be protonated, although the apparent pK is much lower, 5.65. In this case, protonation does not result in an additional hydrogen bond but must be due to better base-stacking interactions for C+ x T. The NMR data show that the environment of the T imino proton is very similar for C x T and C+ x T, although the hydrogen bond acceptor would be expected to be a nitrogen atom in the former case and an oxygen atom in the latter. We propose that for both structures there is an intervening water molecule which in addition reduces backbone strain. We have also measured the fluctuations during molecular dynamics runs in these mismatches. All are greater than for Watson-Crick base-pairs and the C x C mismatch shows very pronounced mobility.
Collapse
Affiliation(s)
- Y Boulard
- CEA, Département de Biologie Cellulaire et Moléculaire, Centre d'Etudes de Saclay, Gif-sur-Yvette, France
| | | | | |
Collapse
|
25
|
Abstract
The sequence organisation of the telomeric regions is extremely similar for all eukaryotes examined to date. Subtelomeric areas may contain large sequence arrays of middle repetitive, complex elements that sometimes have similarities to retrotransposons. In between and within these complex sequences are short, satellite-like repeats. These areas contain very few genes and are thought to be organised into a heterochromatin-like domain. The terminal regions almost invariably consist of short, direct repeats. These repeats usually contain clusters of 2-4 G residues and the strand that contains these clusters (the G strand) always forms the extreme 3'-end of the chromosome. Thus, most telomeric repeats are clearly related to each other which in turn suggests a common evolutionary origin. A number of different structures can be formed by single-stranded telomeric G strand repeats and, as has been suggested recently, by the G strand. Since the main mechanism for the maintenance of telomeric repeats predicts the occurrence of single-stranded extensions of the G strand, the propensity of G-rich DNA to fold into alternative DNA structures may have implications for telomere biology.
Collapse
Affiliation(s)
- R J Wellinger
- Faculté de Médecine, Department de Microbiologie et Infectiologie, Université de Sherbrooke, QC, Canada
| | | |
Collapse
|
26
|
Berners-Price SJ, Corazza A, Guo Z, Barnham KJ, Sadler PJ, Ohyama Y, Leng M, Locker D. Structural transitions of a GG-platinated DNA duplex induced by pH, temperature and box A of high-mobility-group protein 1. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 243:782-91. [PMID: 9057846 DOI: 10.1111/j.1432-1033.1997.00782.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
[1H, 15N] and 1H NMR, and CD spectroscopy are used to show that the duplex d(A-T-A-C-A-T-Pt 7G-Pt7G-T-A-C-A-T-A).d(T-A-T-G-T-A-C-C-A-T-G-T-A-T), where Pt7G is platinated guanine, containing the cis-[Pt(NH3)2]2+ adduct, undergoes reversible temperature-induced (T0.5 310 K) and pH-induced (pKa approximately 4.8) transitions between kinked-duplex and distorted forms, with the latter forms predominating at high temperature and low pH. A related pH-induced structural change was observed for the unplatinated duplex (pKa 4.69, Hill coefficient n = 1.4) but was less cooperative than for the platinated duplex (n = 2). The pH-induced transition is attributed to protonation of cytosine residues and has wider implications, since many reported NMR studies of DNA are carried out near pH 5 to minimize NH-exchange rates. The [Pt(en)]2+ (where en is 1,2-ethanediamine) GG chelate of the same duplex is shown to exist in kinked and distorted forms, and the [1H,15N]-NMR shifts for the kinked form are indicative of the presence of highly stereospecific interactions with the Pt-NH protons. On binding of the duplex platinated with [Pt(NH3)2]2+ to high-mobility-group protein 1 (HMG1) box A, similar changes in shifts of the Pt-NH3 resonances to those induced by raising the temperature or lowering the pH were observed. The specific changes in 1H-NMR chemical shifts of HMG1 box A are consistent with binding of the platinated duplex (intermediate exchange rate on the 1H-NMR time-scale) to the concave face of the protein via helices I and II and the intervening loop.
Collapse
Affiliation(s)
- S J Berners-Price
- Faculty of Science and Technology, Griffith University, Nathan, Brisbane, Australia
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
In the years that have passed since the publication of Wolfram Saenger's classic book on nucleic acid structure (Saenger, 1984), a considerable amount of new data has been accumulated on the range of conformations which can be adopted by DNA. Many unusual species have joined the DNA zoo, including new varieties of two, three and four stranded helices. Much has been learnt about intrinsic DNA curvature, dynamics and conformational transitions and many types of damaged or deformed DNA have been investigated. In this article, we will try to summarise this progress, pointing out the scope of the various experimental techniques used to study DNA structure, and, where possible, trying to discern the rules which govern the behaviour of this subtle macromolecule. The article is divided into six major sections which begin with a general discussion of DNA structure and then present successively, B-DNA, DNA deformations, A-DNA, Z-DNA and DNARNA hybrids. An extensive set of references is included and should serve the reader who wishes to delve into greater detai.
Collapse
Affiliation(s)
- B Hartmann
- Laboratoire de Biochimie Théorique, Institut de Biologie Physico-Chimique, Paris, France
| | | |
Collapse
|
28
|
Lane AN, Peck B. Conformational flexibility in DNA duplexes containing single G.G mismatches. EUROPEAN JOURNAL OF BIOCHEMISTRY 1995; 230:1073-87. [PMID: 7601138 DOI: 10.1111/j.1432-1033.1995.tb20658.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Purine-purine mismatches can base-pair in a variety of configurations depending on solution conditions. The G.G mismatch, which also occurs in the G-quartet structure, has been shown by both x-ray crystallography and NMR to adopt G(anti).G(syn) mispairs, with very different hydrogen bonding patterns [Skelly, J., Edwards, K., Jenkins, T. C. & Neidle, S. (1993) Proc. Natl Acad. Sci. USA 90, 804-808; Cognet, J. A. H., Gabarro-Arpa, J., Le Bret, M., van der Marel, G. A. van Boom, J. H. & Fazakerley, G. V. (1991) Nucleic Acids. Res. 19, 6771-6779] while we have recently suggested the presence of weakly hydrogen-bonded G(anti).G(anti) pairs in solution [Borden, K. L. B., Jenkins, T. C., Skelly, J. V., Brown, T. & Lane, A. N. (1992) Biochemistry 31, 5411-5422]. Spectral overlap and additional exchange processes have made detailed structural analysis difficult in these mismatched oligomers. We have used NMR to characterise the conformations of four duplexes containing single G.G mismatches, including a nonamer d(CATCGGATG), two undecamers d(GCATTGAATGC) and d(CATGTGACGTG) that can each form a self-complementary duplex with a single G.G mispair in the centre, and the non-self-complementary d(GTAACGACATG).d(CATGTGGTTAC). The three self-complementary duplexes have a single set of NMR resonances, and all four duplexes show evidence of conformational exchange at the mismatch site. The N1H resonances of the mismatched G residues each integrate to two protons, ruling out the enol tautomer. They resonate between 10.5-10.7 ppm, far upfield of the Watson-Crick hydrogen-bonded GN1H and exchange readily with water protons. Intraresidue GH8-H1' NOE intensities are two-threefold larger for the mismatched G residues than in G.C base pairs, indicating the presence of syn conformations. NOE time courses for the self-complementary duplexes were consistent with an equimolar mixture of G(syn).G(anti) and G (anti).G(syn) states. By symmetry, these states must be interconverting at a rate that is fast on the chemical shift timescale. In the non-self-complementary undecamer, the NOE data indicated that the distinguishable mismatched G residues also spend a significant, but different, fraction of the time in both the syn and anti conformations. The rate constant for the syn/anti transition in the non-self-complementary undecamer was determined as approximately 14,000 s-1 at 303 K from rotating frame T1 measurements, and the apparent frequency difference was > 250 Hz. Calculations based on NOEs and coupling constants showed that the duplexes are overall in the B form.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- A N Lane
- Laboratory of Molecular Structure, National Institute for Medical Research, England
| | | |
Collapse
|
29
|
|
30
|
Schröder G, Lippert B, Sabat M, Lock CJL, Faggiani R, Song B, Sigel H. Unusual hydrogen bonding patterns of N7metallated, N1deprotonated guanine nucleobases: acidity constants of cis-[Pt(NH3)2(Hegua)2]2+and crystal structures of cis-[Pt(NH3)2(egua)2]·4H2O and cis-[Pt(NH3)2(egua)2]· Hegua·7H2O (Hegua = 9-ethylguanine). ACTA ACUST UNITED AC 1995. [DOI: 10.1039/dt9950003767] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
31
|
Lane A, Ebel SY, Brown T. Properties of multiple G.A mismatches in stable oligonucleotide duplexes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1994; 220:717-27. [PMID: 8143726 DOI: 10.1111/j.1432-1033.1994.tb18672.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The solution structure of the deoxydecanucleotide [sequence: see text] has been determined by NMR methods. This duplex, which contains six G.A mismatches and four Watson-Crick base pairs, is thermodynamically more stable than a decamer where T.A base pairs are substituted for the G.A mismatches, and is less stable than the duplex that contains G.C base pairs. Circular-dichroism spectroscopy indicates an overall B-like conformation for the decamer, but stronger than usual base stacking. 1H-NMR spectroscopy revealed that the N1H groups of the mismatched guanine residues are not hydrogen bonded, and 31P-NMR showed the presence of BII phosphate conformations for the GpA steps. Detailed analysis of the NMR data showed that all nucleotides have anti glycosidic torsion angles and S type sugar puckers. The G.A mismatches pair in the amino form as originally proposed by Li et al. [Li, Y., Zon, G. & Wilson, W. D. (1991) Proc. Natl Acad. Sci. USA 88, 26-30], which results in extensive base-base stacking between the tandem G.A base pairs and their nearest neighbours. The terminal G.A base pairs are less stable than the central base pairs and show evidence of an equilibrium between two conformations, one involving BII phosphate.
Collapse
Affiliation(s)
- A Lane
- National Institute for Medical Research, London, England
| | | | | |
Collapse
|
32
|
Wurdeman RL, Douskey MC, Gold B. DNA methylation by N-methyl-N-nitrosourea: methylation pattern changes in single- and double-stranded DNA, and in DNA with mismatched or bulged guanines. Nucleic Acids Res 1993; 21:4975-80. [PMID: 8177747 PMCID: PMC311415 DOI: 10.1093/nar/21.21.4975] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The detection of abnormal DNA base pairing arrangements and conformations is chemically probed in synthetic 32P-end-labeled deoxyribonucleotide oligomers using N-methyl-N-nitrosourea (MNU) and 2,12,-dimethyl-3,7,11,17-tetraazabicyclo-[11.3.1]heptadeca-1 -[17],2,11,13,15 pentaene-Ni (II) (Ni-complex) with KHSO5. The DNA targets studied are single-stranded (s-s) DNA, double-stranded (d-s) DNA, d-s DNA with G-G, G-A and G-T mismatches, d-s DNA with a single bulged G and d-s DNA with two bulged G's. The effect of the non-Watson--Crick structures on the formation of N7-methylguanine (N7-MeG) by MNU and the oxidation of G by Ni-complex is reported along with the Tm's and circular dichroism spectra of the different duplex oligomers. The results for MNU and Ni-complex show that the qualitative and quantitative character of the cleavage patterns at a G3 run change with the nature of the abnormal base pairing motif. Based on the DNA substrates studied, the results indicate that a combination of reagents which report electronic and steric perturbations can be a useful approach to monitor DNA mismatches and bulges.
Collapse
Affiliation(s)
- R L Wurdeman
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha 68198-6805
| | | | | |
Collapse
|
33
|
Skelly JV, Edwards KJ, Jenkins TC, Neidle S. Crystal structure of an oligonucleotide duplex containing G.G base pairs: influence of mispairing on DNA backbone conformation. Proc Natl Acad Sci U S A 1993; 90:804-8. [PMID: 8430089 PMCID: PMC45758 DOI: 10.1073/pnas.90.3.804] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The structure of the G.G mispaired dodecanucleotide d(CGCGAATTGGCG)2 has been solved by x-ray crystallography and refined to an R factor of 18.8% at 2.2 A resolution for 3513 reflections. The dodecamer crystallizes as a B-type DNA double helix. It contains two G(anti).G(syn) base pairs--i.e., G-4/G-16(anti).G-21/G-9(syn). The Hoogsteen base pairing involves atoms O-6 and N-7 of the guanine in the syn conformation with atoms N-1 and N-2 of the anti-paired purine. One G.G base pair has a bifurcated hydrogen bond between G-4(N-1)...G-21(N-7) and G-4(N-1)...G-21(O-6). There is little overall structural distortion of the double helix induced as a consequence of the mispairing. The helical width is significantly increased by comparison with the structure of the native duplex, and the minor groove width in the 5'-AATT region is decreased. The G.G base pairing induces high-BII phosphate conformations at residues G-9 and T-20 in addition to more normal BII conformations at G-10 and G-22. It is suggested that these backbone aberrations provide signals for the facile repairability of G.G mispairs in DNA.
Collapse
Affiliation(s)
- J V Skelly
- Cancer Research Campaign Biomolecular Structure Unit, Institute of Cancer Research, Sutton, Surrey, United Kingdom
| | | | | | | |
Collapse
|
34
|
Lane A, Martin SR, Ebel S, Brown T. Solution conformation of a deoxynucleotide containing tandem G.A mismatched base pairs and 3'-overhanging ends in d(GTGAACTT)2. Biochemistry 1992; 31:12087-95. [PMID: 1333792 DOI: 10.1021/bi00163a018] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We have used 31P and 1H NMR spectroscopy and circular dichroism to define the solution conformation of d(GTGAACTT)2 which contains tandem G.A mismatched base pairs and 3'-overhanging TT ends. Measurements of coupling constants and NOE intensities show that the sugar puckers of the nucleotides are predominantly in the south domain (i.e., near C2'-endo) and that the glycosidic torsion angles are anti. The sequential NOE intensities indicate the presence of a right-handed helix. Analysis of the 31P and 1H NMR spectra of the duplex shows that the tandem mismatch forms a block in which there are unusual backbone torsion angles (i.e., in the BII state), within an otherwise B-like structure. The chemical shift of the N1H of the mismatched guanosine and NOEs between the mismatched base pairs and their nearest neighbors are inconsistent with the imino pairing present in single A.G mismatches or in the X-ray structure of a tandem mismatch [Privé, G. G., et al. (1987) Science 238, 498-503] but the data are consistent with the amino pairing found by Li et al. (1991) [Li, Y., et al. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 26-30]. The strong base-base stacking both within the tandem G.A block and between the G.A mismatches and their other nearest neighbors offsets the intrinsic destabilizing effects of the mismatch. Further, the 3'-TT overhangs stack onto the ends of the helix and stabilize the duplex against fraying, which accounts for the observed increase in the melting temperature compared with the flush-ended duplex.
Collapse
Affiliation(s)
- A Lane
- Laboratory for Molecular Structure, National Institute for Medical Research, London, U.K
| | | | | | | |
Collapse
|
35
|
Joyce C, Sun X, Grindley N. Reactions at the polymerase active site that contribute to the fidelity of Escherichia coli DNA polymerase I (Klenow fragment). J Biol Chem 1992. [DOI: 10.1016/s0021-9258(18)35792-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
36
|
Gabarro-Arpa J, Cognet JA, Le Bret M. Object Command Language: a formalism to build molecular models and to analyze structural parameters in macromolecules, with applications to nucleic acids. JOURNAL OF MOLECULAR GRAPHICS 1992; 10:166-73, 162. [PMID: 1467332 DOI: 10.1016/0263-7855(92)80051-e] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have written a programming language OCL (Object Command Language) to solve, in a general way, two recurring problems that arise during the construction of molecular models and during the geometrical characterization of macromolecules: how to move precisely and reproducibly any part of a molecular model in any user-defined local reference axes; and how to calculate standard or user-defined structural parameters that characterize the complex geometries of any macromolecule. OCL endows the user with three main capabilities: the definition of subsets of the macromolecule, called objects in OCL, with a formalism from elementary set theory or lexical analysis; the definition of sequences of elementary geometrical operations, called procedures in OCL, enabling one to build arbitrary three-dimensional (3D) orthonormal reference frames, to be associated with previously defined objects; and the transmission of these definitions to programs that allow one to display, to modify and to analyze interactively the molecular structure, or to programs that perform energy minimizations or molecular dynamics. Several applications to nucleic acids are presented.
Collapse
Affiliation(s)
- J Gabarro-Arpa
- Unité de Biochimie-Enzymologie, Institut Gustave-Roussy (U140 INSERM, URA147 CNRS), France
| | | | | |
Collapse
|
37
|
Borden KL, Jenkins TC, Skelly JV, Brown T, Lane AN. Conformational properties of the G.G mismatch in d(CGCGAATTGGCG)2 determined by NMR. Biochemistry 1992; 31:5411-22. [PMID: 1606167 DOI: 10.1021/bi00138a024] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The conformational properties of the DNA duplex d(CGCGAATTGGCG)2, which contains two noncomplementary G.G base pairs, have been examined in aqueous solution by 1H and 31P NMR as a function of temperature. The G.G mismatch is highly destabilizing, with a Tm value 35 K below that observed for the native EcoRI dodecamer. The dodecamer appears symmetric in the NMR spectra and exists largely as an average B-type DNA conformation. However, the 1H and 31P NMR spectra give evidence of considerable conformational heterogeneity at the mismatched nucleotides and their nearest neighbors, which increases with increasing temperature. There is no evidence for a significant population of the syn purine conformation. The imino protons of the mispaired bases G4 and G9 are degenerate, resonate at high field, and exchange readily with solvent. These results indicate that the mispaired bases are only weakly hydrogen-bonded and are only partially stacked into the helix. On raising the temperature, the duplex shows increasing exchange between two or more conformations originating from the mismatch sites. However, these additional conformations maintain their Watson-Crick hydrogen bonding. The increase in chemical exchange is consistent with a quasimelting process for which the G.G sites provide local nuclei. Extensive modeling studies by dynamic annealing have confirmed that the G(anti).G(anti) conformation is favored and that the mispairs are poorly stacked within the helix. The results explain both the poor thermal stability and low hypochromicity of this duplex.
Collapse
Affiliation(s)
- K L Borden
- Laboratory for Molecular Structure, National Institute for Medical Research, Mill Hill, London, U.K
| | | | | | | | | |
Collapse
|