1
|
Rodriguez-Tanty C, Higginson-Clarke D, Hernández M, Pérez R, Vélez-Castro H, Riverón AM, Macías A. Synthesis of 5-Methyl-2′-O-Deoxycytidine Analogs to Determine Monoclonal Antibody Specificity in the Recognition of the 6-(p-Bromobenzoylamino) Caproyl Radical. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/07328319708001362] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
2
|
Iwamoto TA, Kobayashi N, Imoto K, Yamamoto A, Nakamura Y, Yamauchi Y, Okumura H, Tanaka A, Hanaoka F, Shibutani S, Miyagawa S, Mori T. In situ detection of acetylaminofluorene-DNA adducts in human cells using monoclonal antibodies. DNA Repair (Amst) 2005; 3:1475-82. [PMID: 15380103 DOI: 10.1016/j.dnarep.2004.05.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2004] [Revised: 05/26/2004] [Accepted: 05/28/2004] [Indexed: 10/26/2022]
Abstract
The present study was performed to generate monoclonal antibodies capable of detecting N-acetoxy-2-acetylaminofluorene (NA-AAF)-derived DNA adducts in human cells in situ. As an immunogen, we employed NA-AAF-modified single-stranded DNA coupled electrostatically to methylated protein and we produced five different monoclonal antibodies. All of them showed strong binding to NA-AAF-modified DNA, but had undetectable or minimal binding to undamaged DNA. Competitive inhibition experiments revealed that the epitope recognized by these antibodies is N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (dG-C8-AAF) in DNA, although deacetylated N-(deoxyguanosin-8-yl)-2-aminofluorene in DNA is also recognized with slightly less efficiency. In contrast, these antibodies did not bind to 3-(deoxyguanosin-N(2)-yl)-2-acetylaminofluorene in DNA or to UV-induced lesions in DNA. Interestingly, they showed only minimal binding to small AAF-nucleoside adducts (dG-C8-AAF), indicating that DNA regions flanking a DNA-bound adduct, in addition to the adduct itself, are essential for the stable binding of the antibodies. Using an enzyme-linked immunosorbent assay with the most promising antibody (AAF-1), we detected the concentration-dependent induction of NA-AAF-modified adducts in DNA from repair deficient xeroderma pigmentosum (XP) cells treated with physiological concentrations of NA-AAF. Moreover, the assay enabled to confirm that normal human cells efficiently repaired NA-AAF-induced DNA adducts but not XP-A cells. Most importantly, the formation of NA-AAF-induced DNA adducts in individual nuclei of XP cells could be clearly visualized using indirect immunofluorescence. Thus, we succeeded in establishing novel monoclonal antibodies capable of the in situ detection of NA-AAF-induced DNA adducts in human cells.
Collapse
Affiliation(s)
- Taka-aki Iwamoto
- Radioisotope Research Center, Department of Dermatology, Nara Medical University, Kashihara, Nara 634-8521, Japan
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Kriek E. Fifty years of research on N-acetyl-2-aminofluorene, one of the most versatile compounds in experimental cancer research. J Cancer Res Clin Oncol 1992; 118:481-9. [PMID: 1624539 DOI: 10.1007/bf01225261] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
It is just about 50 years since the publication of the report on the toxicity and carcinogenicity of the potent carcinogen N-acetyl-2-aminofluorene (AAF). In 1940 very few reports on the carcinogenic activity of chemical compounds in experimental animals were available. The discovery of pure chemicals as carcinogens, such as AAF, azo dyes and benzo[a]pyrene, provided cancer researchers with a number of tools whereby the progressive changes involved in the induction of cancer could be studied in experimental systems. Contrary to the results with other carcinogens then known, AAF induced numerous types of tumors, but not at the site of application. This finding stimulated a great deal of interest in its use as an experimental carcinogen to study its metabolic fate and mechanism of action. During the following years an ever increasing number of reports appeared on the carcinogenicity of AAF in various species, on its metabolic fate, on the interaction of reactive metabolites with nucleic acids and proteins, and on its mutagenic activity. Particularly studies on the metabolism of AAF and the interaction with nucleic acids have contributed appreciably to our understanding of the mechanism of action of aromatic amines and also of other chemical carcinogens. It can be expected that AAF and its derivatives will continue to be used for specific applications in experimental cancer research. One of the most recent achievements is the preparation of site-specific AAF- and aminofluorene-modified DNA sequences for mutagenesis studies.
Collapse
|
4
|
Santella RM, Zhang YJ, Young TL, Lee BM, Lu XQ. Monitoring human exposure to environmental carcinogens. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 283:165-81. [PMID: 2068984 DOI: 10.1007/978-1-4684-5877-0_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- R M Santella
- Comprehensive Cancer Center, School of Public Health, Columbia University, New York, NY 10032
| | | | | | | | | |
Collapse
|
5
|
Santella RM. Application of new techniques for the detection of carcinogen adducts to human population monitoring. Mutat Res 1988; 205:271-82. [PMID: 3285191 DOI: 10.1016/0165-1218(88)90022-5] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Several techniques have recently been developed for the detection and quantitation of carcinogen-DNA or -protein adducts without the requirement for radioactive carcinogens. These assays can be used to detect adducts in animals or cultured cells exposed to test compounds or in humans exposed to environmental carcinogens. Immunologic, 32P-postlabeling and fluorescence techniques, used on human samples for DNA adduct measurement, are reviewed here. Methods for the detection of carcinogen-protein adducts on human samples are also summarized.
Collapse
Affiliation(s)
- R M Santella
- Division of Environmental Sciences, School of Public Health, Columbia University, New York, NY 10032
| |
Collapse
|
6
|
Abstract
The importance of the polymorphism of DNA in the reaction with the chemical carcinogen N-hydroxyaminofluorene is studied by means of a supercoiled plasmid containing an insert of (dC-dG). Immunochemical titration and the determination of the binding spectrum of -aminofluorene adducts show that the carcinogen reacts with B-DNA but not with Z-DNA and that conformational changes of the B-DNA-Z-DNA junctions occur as a function of the superhelical density.
Collapse
|
7
|
Malfoy B, Rousseau N, Vogt N, Viegas-Pequignot E, Dutrillaux B, Leng M. Nucleotide sequence of an heterochromatic segment recognized by the antibodies to Z-DNA in fixed metaphase chromosomes. Nucleic Acids Res 1986; 14:3197-214. [PMID: 3010230 PMCID: PMC339742 DOI: 10.1093/nar/14.8.3197] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The purpose of this work was to analyse at the molecular level the DNA recognized by the antibodies to Z-DNA in in situ experiments. Antibodies to Z-DNA interact strongly with R-band positive heterochromatic segments of fixed metaphase chromosomes of Cebus (Viegas-Pequignot et al., 1983). These segments are constituted of a satellite DNA the repeat unit of which is about 1520 base pairs long. The base sequence of the repeat unit has been determined. It contains a (AC)n rich region which, in vitro, adopts the Z conformation under topological constraints. Experiments with nuclei suggest that this sequence is not predominantly in the Z conformation in vivo. The polymorphic structure of the (AC)n rich region argues for an active recombination sequence.
Collapse
|
8
|
Abstract
The purpose of this paper is to show that the antibodies to nucleic acids, to nucleosides or to DNA damaged by a physical or a chemical agent, are useful tools in the study of DNA damage and repair. The results obtained with antibodies to nucleosides, antibodies to nucleosides and DNA modified by chemical carcinogens emphasize the potential of immunological methods in three main areas, a) the sensitive detection and quantitation of adducts; b) the visualization of adducts in tissues, individual cells, and along the DNA double helix; c) the study of conformational changes of DNA induced by adducts.
Collapse
|
9
|
Hébert E, Loukakou B, Saint-Ruf G, Leng M. Conformational changes induced in DNA by the in vitro reaction with the mutagenic amine: 3-N,N-acetoxyacetylamino-4,6-dimethyldipyrido (1,2-a: 3', 2'-d) imidazole. Nucleic Acids Res 1985; 12:8553-66. [PMID: 6548807 PMCID: PMC320398 DOI: 10.1093/nar/12.22.8553] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The conformation of synthetic or natural DNAs modified in vitro by covalent binding of N-AcO-A-Glu-P-3 was investigated by fluorescence and circular dichroism. In all cases, substitution occurs mainly on the C8 of guanine residues. In modified poly(dG-dC).poly(dG-dC) or poly(dA-dC).poly(dG-dT) in B conformation, A-Glu-P-3 residues interact strongly with the bases whereas in Z conformation these residues are largely exposed to the solvent and interact weakly with the bases. A-Glu-P-3 and N-acetyl-2-aminofluorene (AAF) residues are equally efficient to induce the B-Z transition of poly(dG-dC).poly(dG-dC) and of poly(dA-dC).poly(dG-dT). Modifications of poly(dG).poly(dC) and calf thymus DNA indicate strong interactions between A-Glu-P-3 and the bases.
Collapse
|
10
|
Tchen P, Fuchs RP, Sage E, Leng M. Chemically modified nucleic acids as immunodetectable probes in hybridization experiments. Proc Natl Acad Sci U S A 1984; 81:3466-70. [PMID: 6374657 PMCID: PMC345529 DOI: 10.1073/pnas.81.11.3466] [Citation(s) in RCA: 131] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Guanine residues in nucleic acids can be modified by treatment with N-acetoxy-N-2-acetylaminofluorene and its 7-iodo derivative in an in vitro nonenzymatic reaction. The modified nucleic acids (ribo or deoxyribo, single or double stranded) are recognized by specific antibodies. They can be immunoprecipitated or used as probes in hybridization experiments and detected by immunochemical techniques.
Collapse
|
11
|
Poirier MC. The use of carcinogen-DNA adduct antisera for quantitation and localization of genomic damage in animal models and the human population. ENVIRONMENTAL MUTAGENESIS 1984; 6:879-87. [PMID: 6389112 DOI: 10.1002/em.2860060615] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The use of antibodies to detect chemical carcinogen-induced DNA damage involves quantitative determination and morphological localization utilizing antisera specific for carcinogen-DNA adducts. In recent years a large number of polyclonal and monoclonal antisera have been produced against individual adducts and modified DNAs with addition products varying in structure from ethyl and methyl groups to aromatic amines, polycyclic aromatic hydrocarbons, aflatoxins, and platinum-ammine complexes. The quantitative assays developed through the use of these antisera are able to detect attomole (10(-18) M) adduct concentrations, corresponding to one adduct in 10(8) nucleotides or a few hundreds of modifications per mammalian cell genome. This review focuses on data generated during the past 3 yr utilizing this immunotechnology as a tool to probe mechanisms of carcinogen-DNA interactions in various model systems and in the human population. Areas discussed in depth include quantitative and morphological studies involving detection of 2-acetylaminofluorene-DNA adducts in rat liver, O6-ethyl and O6-methyl deoxyguanosine adducts in rat brain, benzo[a]pyrene-DNA adducts in mouse skin and cis-diamminedichloroplatinum (II)-DNA adducts in peripheral nucleated blood cells of cancer patients.
Collapse
|
12
|
Strickland PT, Boyle JM. Immunoassay of carcinogen-modified DNA. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1984; 31:1-58. [PMID: 6085171 DOI: 10.1016/s0079-6603(08)60374-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
13
|
Hertzog PJ, Shaw A, Lindsay Smith JR, Garner RC. Improved conditions for the production of monoclonal antibodies to carcinogen-modified DNA, for use in enzyme-linked immunosorbent assays (ELISA). J Immunol Methods 1983; 62:49-58. [PMID: 6409964 DOI: 10.1016/0022-1759(83)90109-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The methodology for the production of monoclonal antibodies to chemical carcinogen-modified DNA has been improved to provide high yields of hybridomas, using guanine-imidazole ring-opened aflatoxin B1-modified DNA as an example (iro-AFB1 DNA). The percentage of immunised mice which responded to iro-AFB1 DNA-protein immunisation and the number of specific hybridomas produced was dependent on the level of modification of DNA. One in three BALB/c mice had detectable (but low) antibody titre when 0.3% modified iro-AFB1 DNA was used and this yielded 2 specific hybridomas, whereas all mice responded at reasonable titres and 6 specific hybridomas were obtained when 3% modified iro-AFB1 DNA was used. Other factors found to improve the number and titre of mice responding to immunisation and the yield of hybridomas were: KLH greater than BSA as carrier protein, C57 BL/6 X BALB/c F1 greater than BALB/c mice for antibody production, fusion success and ascites growth. The conditions limiting the sensitivity and reproducibility of an enzyme-linked immunosorbent assay (ELISA) using these monoclonal antibodies with beta-galactosidase-linked sheep F(ab')2 anti-mouse IgG as the second antibody were also tested. Present experience with AFB1 and other carcinogens indicates that these methods should be applicable to the production of monoclonal antibodies to DNA modified by a wide variety of chemical carcinogens.
Collapse
|
14
|
Lang MC, de Murcia G, Mazen A, Fuchs RP, Leng M, Daune M. Non-random binding of N-acetoxy-N-2-acetylamino-fluorene to chromatin subunits as visualized by immunoelectron microscopy. Chem Biol Interact 1982; 41:83-93. [PMID: 7046967 DOI: 10.1016/0009-2797(82)90019-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The influence of chromatin structure on the accessibility of DNA to the model ultimate carcinogen N-acetoxy-N-2-acetylaminofluorene (N-Aco-AAF) was investigated by means of an immunoelectron microscopic technique developed recently. An homogeneous population of core particles or trinucleosomes from chicken erythrocytes, was submitted to electrophilic attack by N-Aco-AAF. After DNA isolation, N-2-acetylaminofluorene (AAF) binding sites were mapped upon the DNA fragments using specific antibodies as a probe. Our results indicate a non-random binding of AAF along the DNA. Our data support the results of previous studies showing a preferential binding on the linker region.
Collapse
|
15
|
Kakiuchi N, Marck C, Rousseau N, Leng M, De Clerq E, Guschlbauer W. Polynucleotide helix geometry and stability. Spectroscopic, antigenic and interferon-inducing properties of deoxyribose-, ribose-, or 2‘-deoxy-2‘-fluororibose-containing duplexes of poly(inosinic acid) . poly(cytidylic acid). J Biol Chem 1982. [DOI: 10.1016/s0021-9258(19)68127-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
16
|
Perera FP, Weinstein IB. Molecular epidemiology and carcinogen-DNA adduct detection: new approaches to studies of human cancer causation. JOURNAL OF CHRONIC DISEASES 1982; 35:581-600. [PMID: 6282919 DOI: 10.1016/0021-9681(82)90078-9] [Citation(s) in RCA: 221] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
17
|
|
18
|
Müller R, Rajewsky MF. Antibodies specific for DNA components structurally modified by chemical carcinogens. J Cancer Res Clin Oncol 1981; 102:99-113. [PMID: 7040411 DOI: 10.1007/bf00410662] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
|
19
|
Sage E, Gabelman N, Mendez F, Bases R. Immunocytological detection of AAF-DNA adducts in HeLa cell nuclei. Cancer Lett 1981; 14:193-204. [PMID: 7032688 DOI: 10.1016/0304-3835(81)90130-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Acetylaminofluorene-DNA adducts (AAF-DNA) were detected in the nuclei of HeLa cells exposed to N-acetoxy-2-acetylaminofluorene (N-Ac-AAF), using an immunocytological technique and specific antibodies directed against AAF modified DNA. The proportion of cells exhibiting specific nuclear immunoreactivity was dose-dependent. The time course of disappearance of adduct specific nuclear immunoreactivity was compared with removal of N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (dG-C8-AAF) and other adducts.
Collapse
|
20
|
Kyrtopoulos SA, Vrotsou B. The formation and repair of O6-methylguanine in rat liver nucleolar DNA after dimethylnitrosamine administration studied by radioimmunoassay. Chem Biol Interact 1981; 37:191-7. [PMID: 7285243 DOI: 10.1016/0009-2797(81)90176-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The extent of formation and the rate of repair of O6-methylguanine in rat liver nucleolar DNA following administration of a single dose of dimethylnitrosamine have been studied by means of radioimmunoassay for O6-methyldeoxyguanosine. No difference has been found in either the extent of formation or the rate of repair of this lesion between nucleolar and whole nuclear DNA.
Collapse
|
21
|
Leng M, Ptak M, Rio P. Conformation of acetylaminofluorene and aminofluorene modified guanosine and guanosine derivatives. Biochem Biophys Res Commun 1980; 96:1095-102. [PMID: 6254521 DOI: 10.1016/0006-291x(80)90064-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
22
|
Sage E, Leng M. Conformation of poly(dG-dC) . poly(dG-dC) modified by the carcinogens N-acetoxy-N-acetyl-2-aminofluorene and N-hydroxy-N-2-aminofluorene. Proc Natl Acad Sci U S A 1980; 77:4597-601. [PMID: 6933507 PMCID: PMC349891 DOI: 10.1073/pnas.77.8.4597] [Citation(s) in RCA: 103] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Poly(dG-dC) . poly(dG-dC) was modified by reaction with N-acetoxy-N-acetyl-2-aminofluorene (N-AcO-AAF). Two samples with 6.6% and 8.5% modified bases were prepared. The modified bases are randomly distributed along the polymer chain, as deduced from competition experiments between antibodies against N-2-(guanosin-8-yl)-acetylaminofluorene, modified poly(dG-dC) . poly(dG-dC), and modified DNAs. Circular dichroism studies show that poly(dG-dC) . poly(dG-dC) modified by N-AcO-AAF is much more sensitive to the addition of alcohol than poly(dG-dC) . poly(dG-dC). In about 50% (vol/vol) alcohol, both polynucleotides have the same conformation, which is the Z form or a Z-like form. Moreover, in low salt and in the absence of alcohol, poly(dG-dC) . poly(dG-dC) modified by N-AcO-AAF is partially in the Z form. Poly(dG-dC) . poly(dG-dC) modified by N-hydroxy-N-2-aminofluorene can also adopt the Z form, but the transition is induced at a higher percentage than that of poly(dG-dC) . poly(dG-dC) modified by N-AcO-AAF. In low salt and in the absence of alcohol, no Z form was detected in poly(dG-dC) . poly(dG-dC) modified by N-hydroxy-N-2-aminofluorene.
Collapse
|
23
|
Abstract
Antibodies to Guo-AF were elicited in rabbits by immunization with bovine serum albumin -Guo-AF conjugate. The antibodies were purified by affinity chromatography. The affinity of the antibodies towards several ligands was studied by radioimmunoassays. The antibodies recognize Gua-AAF and Guo-AF (K(Guo-AF)/K(Guo-AAF) congruent to 25). The circular dichroism of Guo-AF as a function of pH is reported.
Collapse
|
24
|
Munns TW, Liszewski MK. Antibodies specific for modified nucleosides: an immunochemical approach for the isolation and characterization of nucleic acids. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1980; 24:109-65. [PMID: 7005966 DOI: 10.1016/s0079-6603(08)60673-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
|
25
|
Spodheim-Maurizot M, Dreux M, Saint-Ruf G, Leng M. Alkaline stability of guanosine and some of its derivatives modified by the carcinogen N-acetoxyacetylaminofluorene. Nucleic Acids Res 1979; 7:2347-56. [PMID: 42882 PMCID: PMC342388 DOI: 10.1093/nar/7.8.2347] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The alkaline treatment of Guo, dGuo, dGMP and denatured DNA modified by N-acetoxyacetylaminofluorene (N-AcO-AAF) was performed in 0.1 M NaOH at 40 degrees C. The kinetics of the reaction were followed by ultraviolet absorption and by chromatographic methods and were found different for the four products under study. Circular dichroism spectra show differences in the environment of acetylaminofluorene residue in these products. The alkaline treatment of Guo-AAF (and dGuo-AAF) leads to the formation of three products. These products were separated by thin layer chromatography and by HPLC and were characterized by spectroscopic methods. One is the already known unstable Guo-AF (and respectively dGuo-AF) (1). The other two products are relatively stable products of the transformation of Guo-AF (or dGuo-AF). These last ones present almost identical ultraviolet absorption spectra, but very different circular dichroism spectra.
Collapse
|
26
|
Sage E, Spodheim-Maurizot M, Rio P, Leng M, Fuchs RP. Discrimination by antibodies between local defects in DNA induced by 2-aminofluorene derivatives. FEBS Lett 1979; 108:66-8. [PMID: 93055 DOI: 10.1016/0014-5793(79)81180-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
27
|
de Murcia G, Lang MC, Freund AM, Fuchs RP, Duane MP, Sage E, Leng M. Electron microscopic visualization of N-acetoxy-N-2-acetylaminofluorene binding sites in ColE1 DNA by means of specific antibodies. Proc Natl Acad Sci U S A 1979; 76:6076-80. [PMID: 293703 PMCID: PMC411805 DOI: 10.1073/pnas.76.12.6076] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
ColE1 DNA has been allowed to react in vitro with N-acetoxy-N-2-[14C]acetylaminofluorene in the range of 0-15 N-2-[14C]acetylaminofluorene residues bound per molecule of DNA, at the C8 of guanine residues. Purified rabbit antibodies to both N-2-(guanosine-8-yl)-acetylaminofluorene and native DNA that had reacted with N-acetoxy-N-2-acetylaminofluorene were shown by electron microscopy to recognize specifically the acetylaminofluorene-modified ColE1 DNA. The antibodies bound to DNA were visualized either per se or after reaction with goat anti-rabbit immunoglobulins coupled with ferritin. There was a linear relationship between the average number of antibodies bound per DNA molecule and the number of N-2-(deoxyguanosine-8yl)-acetylaminofluorene residues per DNA molecule. The slope of this straight line was equal to 0.4. Due to the bivalence of the immunoglobulins one would expect a value of 0.5; we actually observed an important fraction of the bound antibodies crosslinking two parts of the same (or of another) DNA molecule.
Collapse
|
28
|
Antibodies to chemically modified guanylic acid as a tool in structural studies of nucleic acids. J Biol Chem 1979. [DOI: 10.1016/s0021-9258(19)86382-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
29
|
Spodheim-Maurizot M, Saint-Ruf G, Leng M. Conformational changes induced in DNA by in vitro reaction with N-hydroxy-N-2-aminofluorene. Nucleic Acids Res 1979; 6:1683-94. [PMID: 450711 PMCID: PMC327800 DOI: 10.1093/nar/6.4.1683] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The conformation of DNA modified in vitro by the covalent binding of N-OH-AF was investigated by ultraviolet absorbance, circular dichroism and by radioimmunoassay using specific antibodies against Guo-AAF and nDNA-AAF. The results obtained by both physico-chemical and immunological methods are in agreement with a model involving destabilized regions in the double helical DNA around the carcinogen molecule in which, however, the -AF residues are stacked to the adjacent nucleotides. The RIA results show that the -AF residues are less accessible to antibodies in native than in denatured DNA-AF and thus suggest -AF residues partially buried in the interior of the DNA helix. The present model is compared to the one existing for DNA modified by reaction with N-AcO-AAF (DNA-AAF) (1,2).
Collapse
|