Skip to main content
NCBI home page
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1986 Jan;83(1):28–32. doi: 10.1073/pnas.83.1.28

O4-Methyl, -ethyl, or -isopropyl substituents on thymidine in poly(dA-dT) all lead to transitions upon replication.

B Singer, S J Spengler, H Fraenkel-Conrat, J T Kuśmierek
PMCID: PMC322784  PMID: 3455756

Abstract

In a previous paper, we reported that O4-methyl dTTP can be incorporated into poly(dA-dT) in place of thymidine without distortion of the helical structure, but on replication it could behave as deoxycytidine and misincorporate dGTP. Only weak interactions are possible for any O4-modified T X A pair. While O4-alkyl T X G pairing should be favored, experiments to detect the ability of Escherichia coli DNA polymerase I (pol I) to utilize the triphosphate as dCTP were ambiguous. dTTPs with larger alkyl groups (ethyl, isopropyl) have now been synthesized and tested for their recognition as dTTP by pol I. Enhanced steric hindrance could be expected, particularly for O4-isopropyl dTTP, which has a three-carbon branched chain. However, both compounds behaved qualitatively like O4-methyl dTTP, being incorporated into poly(dA-dT) and then directing deoxyguanosine misincorporation by pol I. Quantitative comparisons of mutagenicity were not possible because of the finding that, unlike polymers made with O4-methyl dTTP, those made with ethyl or isopropyl dTTP were resistant to hydrolysis by using a variety of nucleases. The frequent misincorporations of dGTP would be expected to produce transitions in vivo. O4-ethyldeoxythymidine is very poorly repaired in vivo, which would also be expected for repair of O4-isopropyldeoxythymidine. Therefore, under suitable conditions, these particular carcinogen products are likely to be initiators of carcinogenesis.

Full text

PDF
28

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Balmain A., Pragnell I. B. Mouse skin carcinomas induced in vivo by chemical carcinogens have a transforming Harvey-ras oncogene. Nature. 1983 May 5;303(5912):72–74. doi: 10.1038/303072a0. [DOI] [PubMed] [Google Scholar]
  2. Brennand J., Saffhill R., Fox M. The effects of methylated thymidines upon cultures of V79 cells and the mechanism of incorporation of O4-methylthymidine into their DNA. Carcinogenesis. 1982;3(2):219–222. doi: 10.1093/carcin/3.2.219. [DOI] [PubMed] [Google Scholar]
  3. Dolan M. E., Scicchitano D., Singer B., Pegg A. E. Comparison of repair of methylated pyrimidines in poly(dT) by extracts from rat liver and Escherichia coli. Biochem Biophys Res Commun. 1984 Aug 30;123(1):324–330. doi: 10.1016/0006-291x(84)90416-9. [DOI] [PubMed] [Google Scholar]
  4. Druckrey H., Preussmann R., Ivankovic S., Schmähl D. Organotrope carcinogene Wirkungen bei 65 verschiedenen N-Nitroso-Verbindungen an BD-Ratten. Z Krebsforsch. 1967;69(2):103–201. [PubMed] [Google Scholar]
  5. Duesberg P. H. Activated proto-onc genes: sufficient or necessary for cancer? Science. 1985 May 10;228(4700):669–677. doi: 10.1126/science.3992240. [DOI] [PubMed] [Google Scholar]
  6. Early T. A., Olmsted J., 3rd, Kearns D. R., Lezius A. G. Base pairing structure in the poly d(G-T) double helix: wobble base pairs. Nucleic Acids Res. 1978 Jun;5(6):1955–1970. doi: 10.1093/nar/5.6.1955. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Goth R., Rajewsky M. F. Molecular and cellular mechanisms associated with pulse-carcinogenesis in the rat nerbous system by ethyinitrosourea: ethylation of nucleic acids and elimination rates of ethylated bases from the DNA of different tissues. Z Krebsforsch Klin Onkol Cancer Res Clin Oncol. 1974;82(1):37–64. doi: 10.1007/BF00304382. [DOI] [PubMed] [Google Scholar]
  8. HOARD D. E., OTT D. G. CONVERSION OF MONO- AND OLIGODEOXYRIBONUCLEOTIDES TO 5-TRIPHOSPHATES. J Am Chem Soc. 1965 Apr 20;87:1785–1788. doi: 10.1021/ja01086a031. [DOI] [PubMed] [Google Scholar]
  9. Hall J. A., Saffhill R. The incorporation of O6-methyldeoxyguanosine and O4-methyldeoxythymidine monophosphates into DNA by DNA polymerases I and alpha. Nucleic Acids Res. 1983 Jun 25;11(12):4185–4193. doi: 10.1093/nar/11.12.4185. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hu Y. C., Guttenplan J. B. Evidence for a major premutagenic ethyldeoxythymidine-DNA adduct in an in vivo system: N-nitroso-N-ethylurea-treated Salmonella typhimurium. Carcinogenesis. 1985 Oct;6(10):1513–1516. doi: 10.1093/carcin/6.10.1513. [DOI] [PubMed] [Google Scholar]
  11. Kuśmierek J. T., Singer B. Reaction of diazoalkanes with 1-substituted 2, 4-dioxopyrimidines. Formation of O2, N-3 and O4-alkyl products. Nucleic Acids Res. 1976 Apr;3(4):989–1000. doi: 10.1093/nar/3.4.989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Loeb L. A., Kunkel T. A. Fidelity of DNA synthesis. Annu Rev Biochem. 1982;51:429–457. doi: 10.1146/annurev.bi.51.070182.002241. [DOI] [PubMed] [Google Scholar]
  13. Morimoto K., Tanaka A., Yamaha T. Reaction of 1-n-propyl-1-nitrosourea with DNA in vitro. Carcinogenesis. 1983 Nov;4(11):1455–1458. doi: 10.1093/carcin/4.11.1455. [DOI] [PubMed] [Google Scholar]
  14. Park K. K., Archer M. C., Wishnok J. S. Alkylation of nucleic acids by N-nitrosodi-n-propyl-amine: evidence that carbonium ions are not significantly involved. Chem Biol Interact. 1980 Feb;29(2):139–144. doi: 10.1016/0009-2797(80)90028-9. [DOI] [PubMed] [Google Scholar]
  15. Richardson F. C., Dyroff M. C., Boucheron J. A., Swenberg J. A. Differential repair of O4-alkylthymidine following exposure to methylating and ethylating hepatocarcinogens. Carcinogenesis. 1985 Apr;6(4):625–629. doi: 10.1093/carcin/6.4.625. [DOI] [PubMed] [Google Scholar]
  16. Saffhill R., Fox M. The incorporation of O4-methylthymidine into V79A cell DNA when present in the cell culture medium. Carcinogenesis. 1980 Jun;1(6):487–493. doi: 10.1093/carcin/1.6.487. [DOI] [PubMed] [Google Scholar]
  17. Saffhill R. In vitro reaction of N-n-butyl-N-nitrosourea and n-butyl methanesulphonate with guanine and thymine bases of DNA. Carcinogenesis. 1984 May;5(5):621–625. doi: 10.1093/carcin/5.5.621. [DOI] [PubMed] [Google Scholar]
  18. Shisa H., Hiai H. Genetically determined susceptibility of Fischer 344 rats to propylnitrosourea-induced thymic lymphomas. Cancer Res. 1985 Apr;45(4):1483–1487. [PubMed] [Google Scholar]
  19. Singer B., Abbott L. G., Spengler S. J. Assessment of mutagenic efficiency of two carcinogen-modified nucleosides, 1,N6-ethenodeoxyadenosine and O4-methyldeoxythymidine, using polymerases of varying fidelity. Carcinogenesis. 1984 Sep;5(9):1165–1171. doi: 10.1093/carcin/5.9.1165. [DOI] [PubMed] [Google Scholar]
  20. Singer B. All oxygens in nucleic acids react with carcinogenic ethylating agents. Nature. 1976 Nov 25;264(5584):333–339. doi: 10.1038/264333a0. [DOI] [PubMed] [Google Scholar]
  21. Singer B., Bodell W. J., Cleaver J. E., Thomas G. H., Rajewsky M. F., Thon W. Oxygens in DNA are main targets for ethylnitrosourea in normal and xeroderma pigmentosum fibroblasts and fetal rat brain cells. Nature. 1978 Nov 2;276(5683):85–88. doi: 10.1038/276085a0. [DOI] [PubMed] [Google Scholar]
  22. Singer B., Fraenkel-Conrat H., Kuśmierek J. T. Preparation and template activities of polynucleotides containing O2- and O4-alkyluridine. Proc Natl Acad Sci U S A. 1978 Apr;75(4):1722–1726. doi: 10.1073/pnas.75.4.1722. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Singer B., Kröger M., Carrano M. O2- and O4-alkyl pyrimidine nucleosides: stability of the glycosyl bond and of the alkyl group as a function of pH. Biochemistry. 1978 Apr 4;17(7):1246–1250. doi: 10.1021/bi00600a018. [DOI] [PubMed] [Google Scholar]
  24. Singer B., Pergolizzi R. G., Grunberger D. Synthesis and coding properties of dinucleoside diphosphates containing alky pyrimidines which are formed by the action of carcinogens on nucleic acids. Nucleic Acids Res. 1979 Apr;6(4):1709–1719. doi: 10.1093/nar/6.4.1709. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Singer B., Spengler S., Bodell W. J. Tissue-dependent enzyme-mediated repair or removal of O-ethyl pyrimidines and ethyl purines in carcinogen-treated rats. Carcinogenesis. 1981;2(10):1069–1073. doi: 10.1093/carcin/2.10.1069. [DOI] [PubMed] [Google Scholar]
  26. Singer B., Sági J., Kuśmierek J. T. Escherichia coli polymerase I can use O2-methyldeoxythymidine or O4-methyldeoxythymidine in place of deoxythymidine in primed poly(dA-dT).poly(dA-dT) synthesis. Proc Natl Acad Sci U S A. 1983 Aug;80(16):4884–4888. doi: 10.1073/pnas.80.16.4884. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Sukumar S., Notario V., Martin-Zanca D., Barbacid M. Induction of mammary carcinomas in rats by nitroso-methylurea involves malignant activation of H-ras-1 locus by single point mutations. Nature. 1983 Dec 15;306(5944):658–661. doi: 10.1038/306658a0. [DOI] [PubMed] [Google Scholar]
  28. Swenberg J. A., Dyroff M. C., Bedell M. A., Popp J. A., Huh N., Kirstein U., Rajewsky M. F. O4-ethyldeoxythymidine, but not O6-ethyldeoxyguanosine, accumulates in hepatocyte DNA of rats exposed continuously to diethylnitrosamine. Proc Natl Acad Sci U S A. 1984 Mar;81(6):1692–1695. doi: 10.1073/pnas.81.6.1692. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES