Detection of endonuclease III- and 8-oxoguanine glycosylase-sensitive base modifications in γ-irradiated DNA and cells by the Aldehyde Reactive Probe (ARP) assay

Mohammed Mohsin Ali, Satofumi Kurisu, Yoshihiro Yoshioka, Hiroaki Terato, Yoshihiko Ohyama, Kihei Kubo, Hiroshi Ide

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Ionizing radiation generates diverse DNA lesions that differentially induce cell death and mutations. In the present study, calf thymus DNA (400 μg/ml) and HeLa cells were irradiated by 60Co ã-rays, and abasic (AP) sites and endonuclease (Endo)III- and 8-oxoguanine glycosylase (hOGG1)-sensitive base modifications in DNA were quantitated by the aldehyde reactive probe (ARP) assay. The irradiation of calf thymus DNA in phosphate buffer generated 91 Endo III- and 100 hOGG1-sensitive base modifications and 110 AP sites per 10 6 base pairs (bp) per Gy. The yield of the lesions in Tris buffer was 41- to 91-fold lower than that in phosphate, demonstrating a radioprotective effect of Tris. The HeLa cell chromosomal DNA contained 12 Endo III- and 3.8 hOGG1-sensitive base modifications and less than 1 AP sites per 106 bp as endogenous damage, and their level was increased by irradiation. The yields of the damage at 1 Gy (roughly equivalent to the lethal dose of HeLa cells [1.6-1.8 Gy]) were 0.13 Endo III, 0.091 hOGG1, and 0.065 AP sites per 106 bp, showing that irradiation with a lethal dose brought about only a marginal increase in base damage relative to an endogenous one. A comparison of the present data with those reported for DNA strand breaks supports the primary importance of double-strand breaks and clustered lesions as lethal damages formed by ionizing radiation.

Original languageEnglish
Pages (from-to)229-237
Number of pages9
JournalJournal of Radiation Research
Volume45
Issue number2
DOIs
Publication statusPublished - Jun 1 2004
Externally publishedYes

    Fingerprint

Keywords

  • γ-Irradiation
  • ARP assay
  • Damage detection
  • Endo III-sensitive base modifications
  • hOGG1-sensitive base modifications

ASJC Scopus subject areas

  • Agricultural and Biological Sciences (miscellaneous)
  • Radiology Nuclear Medicine and imaging
  • Radiation
  • Radiological and Ultrasound Technology

Cite this