DNA polymerase. cap alpha. and. beta. activities during the cell cycle and their role in heat radiosensitization in Chinese hamster ovary cells

Journal Article · Sun Sep 01 04:00:00 EDT 1985 · Radiat. Res.; (United States)

DOI:https://doi.org/10.2307/3576756· OSTI ID:5228100

Mivechi, N F; Dewey, W C

The levels of DNA polymerase ..cap alpha.. and ..beta.. activities were measured during the cell cycle using a total cell homogenate technique. The results indicate a decrease in the levels of both enzyme activities during G1 phase and a gradual increase as cells enter the S phase. The recovery of DNA polymerase activities was measured after heating for 10 min at 45.5/sup 0/C during the G1 phase or S phase. This treatment reduced the levels of DNA polymerase ..beta.. activity to 20-30% and DNA polymerase ..cap alpha.. activity to 40-50% of their control activity for both G1 and S phase. The activity of DNA polymerase ..beta.. recovered fully during 20-25 hr after heating for both G1 phase or S phase cells. There was no recovery of the activity of DNA polymerase ..cap alpha.. during this time. Survival was measured when cells were irradiated at various times after hyperthermia and for both G1 and S phase the interaction between heat and X rays disappeared by 20-25 hr after heating and the same increase was observed for the recovery of DNA polymerase ..beta.. activity. These results suggest that ..beta.. polymerase may be an important enzyme involved in repairing X-ray-induced damage that can result in cell lethality.

• Research Organization: Univ. of California, San Francisco
• OSTI ID: 5228100
• Journal Information: Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 103:3; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

560121* -- Radiation Effects on Cells-- External Source-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL CELLS
ANTI-INFECTIVE AGENTS
ANTIBIOTICS
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BODY TEMPERATURE
CELL CYCLE
CELL KILLING
CHO CELLS
CYCLOHEXIMIDE
DNA POLYMERASES
DRUGS
ELECTROMAGNETIC RADIATION
ENZYME ACTIVITY
ENZYMES
FUNGICIDES
HYPERTHERMIA
IONIZING RADIATIONS
LABELLED COMPOUNDS
NUCLEOTIDYLTRANSFERASES
PESTICIDES
PHOSPHORUS-GROUP TRANSFERASES
POLYMERASES
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RECOVERY
REPAIR
SURVIVAL CURVES
TEMPERATURE EFFECTS
TRANSFERASES
TRITIUM COMPOUNDS
X RADIATION