Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Formation of a stable triplex from a single DNA strand


HOMOPURINE·homopyrimidine DNA sequences have been shown to form triple-stranded structures readily under appropriate conditions1–5. Interest in DNA triplexes arises from potential applications of intermolecular triplexes as antisense inhibitors of gene expression6–8 and from the possibility that intramolecular triplexes may have a role in gene expression and recombination1. We recently presented NMR evidence for triplex formation from the DNA oligonucleotides d(GA)4 and d(TC)4, which showed unambiguously that the second pyrimidine strand is Hoogsteen base paired and the cytosines are protonated at N3 as required9,10. To obtain a more well defined triplex, and to provide a model for in vivo triplex structures, we have designed and synthesized a 28-base DNA oligomer with a sequence that could potentially fold to form a triplex containing both T·A·T and C +·G·C triplets. Our NMR results indicate that the conformation at pH5.5 is an intramolecular triplex and that a significant amount of triplex remains even at pH 8.0.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Similar content being viewed by others


  1. Wells, R. D., Collier, D. A., Hanvey, J. C., Shimizu, M. & Wohlrab, F. FASEB J. 2, 2939–2949 (1988).

    Article  CAS  Google Scholar 

  2. Felsenfeld, G., Davies, D. R. & Rich, A. J. Am. chem. Soc. 79, 2023–2024 (1957).

    Article  CAS  Google Scholar 

  3. Riley, M., Maling, B. & Chemberlin, M. J. J. molec. Biol. 20, 359–389 (1966).

    Article  CAS  Google Scholar 

  4. Lee, J. S., Johnson, D. A. & Morgan, A. R. Nucleic Acids Res. 6, 3073–3091 (1979).

    Article  CAS  Google Scholar 

  5. Arnott, S. & Selsing, E. J. molec Biol. 108, 619 (1974).

    Google Scholar 

  6. Cooney, M., Czernuszewicz, G., Postel, E. H., Flint, S. J. & Hogan, M. E. Science 241, 456–459 (1988).

    Article  ADS  CAS  Google Scholar 

  7. Praseuth, D. et al. Proc. natn. Acad. Sci. U.S.A. 85, 1349–1353 (1988).

    Article  ADS  CAS  Google Scholar 

  8. Moser, H. E. & Dervan, P. B. Science 238, 645–650 (1987).

    Article  ADS  CAS  Google Scholar 

  9. Rajagopal, P. & Feigon, J. Biochemistry 28, 7859–7870 (1989).

    Article  CAS  Google Scholar 

  10. Rajagopal, P. & Feigon, J. Nature 339, 637–640 (1989).

    Article  ADS  CAS  Google Scholar 

  11. Hoogsteen, K. Acta crystallogr. 12, 822–823 (1959).

    Article  CAS  Google Scholar 

  12. Mirkin, S. M., Lyamichev, V. I., Drushlyak, K. N., Dobrynin, V. N., Filippov, S. A. & Frank-Kamenetskii, M. D. Nature 330, 495–497 (1987).

    Article  ADS  CAS  Google Scholar 

  13. Larsen, A. & Weintraub, H. Cell 29, 609–622 (1982).

    Article  CAS  Google Scholar 

  14. Schon, E., Evans, T., Welsh, J. & Efstratiadis, A. Cell 35, 837–848 (1983).

    Article  CAS  Google Scholar 

  15. Pulleyblank, D. E., Haniford, D. B., & Morgan, A. R. Cell 42, 271–280 (1985).

    Article  CAS  Google Scholar 

  16. Htun, H. & Dahlberg, J. E. Science 241, 1791–1796 (1988).

    Article  ADS  CAS  Google Scholar 

  17. Hanvey, J. C., Shimizu, M. & Wells, R. D. Proc. natn. Acad. Sci. U.S.A. 85, 6292–6296 (1988).

    Article  ADS  CAS  Google Scholar 

  18. Hanvey, J. C., Klyski, J. & Wells, R. D. J. biol. Chem. 263, 7386–7396 (1988).

    CAS  PubMed  Google Scholar 

  19. Johnson, B. H. Science 241, 1800–1804 (1988).

    Article  ADS  Google Scholar 

  20. Voloshin, O. N., Mirkin, S. M., Lyamichev, V. L., Belotserkovskii, B. P. & Frank-Kamenetskii, M. D. Nature 333, 475–476 (1988).

    Article  ADS  CAS  Google Scholar 

  21. Htun, H. & Dahlberg, J. E. Science 243, 1571–1576 (1989).

    Article  ADS  CAS  Google Scholar 

  22. de los Santos, C., Rosen, M. & Patel, D. Biochemistry 28, 7282–7289 (1989).

    Article  CAS  Google Scholar 

  23. Kumar, A., Ernst, R. R. & Wüthrich, K. Biochem. biophys. Res. Commun. 95, 1–6 (1980).

    Article  CAS  Google Scholar 

  24. Boelens, R., Scheek, R. M., Dijkstra, K. & Kaptein, R. J. magn. Res. 62, 378–386 (1986).

    ADS  Google Scholar 

  25. Wüthrich, K. NMR of Proteins and Nucleic Acids, 292 (Wiley, New York, 1986).

    Google Scholar 

  26. Scheffer, I. E., Elson, E. I. & Baldwin, R. L. J. molec. Biol. 48, 145–171 (1970).

    Article  Google Scholar 

  27. van de Ven, F. J. M. & Hilbers, C. W. Eur. J. Biochem. 178, 1–38 (1988).

    Article  CAS  Google Scholar 

  28. Hilbers, C. W. et al. Biochimie 67, 685–695 (1985).

    Article  CAS  Google Scholar 

  29. Rich, A., Nordheim, A. & Wang, A. H.-J. A. Rev. Biochem. 53, 791–846 (1984).

    Article  CAS  Google Scholar 

  30. Griffin, L. C. & Dervan, P. B. Science 245, 967–971 (1989).

    Article  ADS  CAS  Google Scholar 

  31. Kintanar, A., Klevit, R. E. & Reid, B. R. Nucleic Acids Res. 15, 5845–5861 (1987).

    Article  CAS  Google Scholar 

  32. Hilbers, C. W. in Biological Applications of Magnetic Resonance (ed. Shulman, R. G.) 1 (Academic, New York, 1979).

    Book  Google Scholar 

  33. Sklenář, V. & Bax, A. J. magn. Res. 74, 469 (1987).

    ADS  Google Scholar 

  34. States, D. J., Haberkorn, R. A. & Ruben, D. J. J. magn. Res. 48, 286–291 (1982).

    ADS  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and permissions

About this article

Cite this article

Sklenár̆, V., Felgon, J. Formation of a stable triplex from a single DNA strand. Nature 345, 836–838 (1990).

Download citation

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing