Deficient repair and degradation of DNA in X-irradiated L5178Y S/S cells: cell-cycle and temperature dependence

Journal Article · Wed Aug 01 04:00:00 EDT 1979 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3575103· OSTI ID:5705929

Ueno, A M; Goldin, E M; Cox, A B; Lett, J T

The rejoining of DNA strand breaks induced by X rays in the radiosensitive S/S variant of the L5178Y murine leukemic lymphoblast has been studied by alkaline-EDTA-sucrose sedimentation using swinging-bucket and zonal rotors. After irradiation, incubation resulted in an increase in DNA size, but the DNA structures were not restored in all cells, even when the x-ray dose was only 50 rad. Subsequently, 10 to 20 h after irradiation, heavily degraded DNA began to appear. When cells were irradiated at different parts of the cycle, the extent of DNA degradation varied in a fashion similar to survival: Least DNA degradation was found after irradiation at the most radioresistant stage (G/sub 1/ + 8 h), and most DNA degradation occurred after irradiation at the radiosensitive stage (G/sub 1/). Changes in cell survival caused by postirradiation hypothermia were also reflected in the extent of DNA degradation. Populations of G/sub 1/ cells, which show marked increases in survival after postirradiation hypothermic exposure, exhibited a lower level of DNA degradation, whereas populations of G/sub 1/ + 8 h cells, whose survival is affected little by postirradiation hypothermia, showed limited changes in DNA degradation. The onset of degradation was delayed by hypothermia in all cases.

• Research Organization: Colorado State Univ., Fort Collins
• OSTI ID: 5705929
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 79:2; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

550201 -- Biochemistry-- Tracer Techniques
560121* -- Radiation Effects on Cells-- External Source-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BODY TEMPERATURE
CARBOXYLIC ACIDS
CELL CULTURES
CELL CYCLE
CHELATING AGENTS
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
DECOMPOSITION
DNA
EDTA
ELECTROMAGNETIC RADIATION
HYPOTHERMIA
IONIZING RADIATIONS
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
RADIATION CHEMISTRY
RADIATION EFFECTS
RADIATIONS
RADIOLYSIS
RADIOSENSITIVITY
RECOVERY
REPAIR
SEDIMENTATION
STRAND BREAKS
SURVIVAL TIME
SYNCHRONOUS CULTURES
TEMPERATURE DEPENDENCE
X RADIATION