New light-sensitive nucleosides for caged DNA strand breaks

Chembiochem. 2002 Jan 4;3(1):54-60. doi: 10.1002/1439-7633(20020104)3:1<54::AID-CBIC54>3.0.CO;2-2.


Phototriggered bod cleavage has found wide application in chemistry as well as in biology. Nevertheless, there are only a few methods available for site-specific photochemical induction of DNA strand scission despite numerous potential applications. In this study we report the development of new photocleavable nucleotides based on the photochemistry of o-nitrobenzyl esters. The light-sensitive moieties were generated through introduction of o-nitrophenyl groups at the 5'C position of the nucleoside sugar backbone. The newly synthesized, modified nucleosides were incorporated in oligonucleotides and are able to build stable DNA duplexes. In such a way modified oligonucleotides ca cleaved site-specifically upon irradiation with > 360 nm light with high efficiency. Furthermore, we show that these modifications can be bypassed in DNA synthesis promoted by Thermus aquaticus DNA polymerase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / metabolism
  • Base Sequence
  • Circular Dichroism
  • DNA / chemistry*
  • DNA / radiation effects
  • DNA Damage*
  • DNA Primers
  • DNA Replication
  • DNA, Bacterial / chemistry
  • DNA, Bacterial / genetics
  • DNA, Bacterial / radiation effects
  • DNA-Directed DNA Polymerase / metabolism
  • Light
  • Nucleosides* / radiation effects
  • Thermus / enzymology
  • Thermus / genetics


  • Bacterial Proteins
  • DNA Primers
  • DNA, Bacterial
  • Nucleosides
  • DNA
  • DNA-Directed DNA Polymerase