X-ray-related potentially lethal damage expressed by chromosome condensation and the influence of caffeine

Journal Article · Sun Oct 01 00:00:00 EDT 1989 · Radiation Research; (USA)

DOI:https://doi.org/10.2307/3577635· OSTI ID:5224390

Sasaki, H; Nishimoto, T ^[1]

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1. Kyushu Univ., Fukuoka (Japan)

Caffeine has been reported to induce premature chromosome condensation (PCC) in S-phase cells in the presence of an inhibitor of DNA synthesis. We found that when S-phase cells are treated with caffeine and hydroxyurea after X irradiation, substantially more potentially lethal damage (PLD) is expressed, but the addition of cycloheximide, which inhibits PCC induction in S-phase cells, in the presence of caffeine and hydroxyurea reduces the expression of PLD to the same level as seen with caffeine alone. This can be interpreted to mean that the expression of PLD seen with caffeine in the absence of an inhibitor of DNA synthesis is not associated with chromosome condensation. Evidence that PCC induction in S-phase cells and the influence of caffeine on PLD expression were suppressed by incubation at 40 degrees C of tsBN75 cells with a ts defect in ubiquitin-activating enzyme indicates the involvement of ubiquitin in these two processes. These observations as well as previous findings on ubiquitin suggest to us that caffeine induces changes in DNA-chromatin conformation, which are caused by induction of PCC or ubiquitination of chromosomal protein. Such changes occurring postirradiation would favor expression of PLD.

• OSTI ID: 5224390
• Journal Information: Radiation Research; (USA), Vol. 120:1; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CAFFEINE
RADIOSENSITIVITY EFFECTS
DNA
CHEMICAL RADIATION EFFECTS
HYDROXY COMPOUNDS
AMIDES
HYDROXYUREA
CELL CYCLE
CHROMOSOMES
DNA REPLICATION
MUTATIONS
X RADIATION
ANALEPTICS
AROMATICS
AZAARENES
CENTRAL NERVOUS SYSTEM AGENTS
CHEMISTRY
DRUGS
ELECTROMAGNETIC RADIATION
HETEROCYCLIC COMPOUNDS
IONIZING RADIATIONS
NUCLEIC ACID REPLICATION
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PURINES
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
XANTHINES
560151* - Radiation Effects on Animals- Man