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

Journal Article · Sun Oct 01 04:00:00 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), Journal Name: Radiation Research; (USA) Vol. 120:1; ISSN RAREA; ISSN 0033-7587
• Country of Publication: United States
• Language: English

Related Subjects

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