Survival of synchronized diploid yeast after ultraviolet irradiation

Journal Article · Mon Sep 01 00:00:00 EDT 1975 · Radiat. Res., v. 63, no. 3, pp. 474-482

DOI:https://doi.org/10.2307/3574099· OSTI ID:4149064

Nunes, E; Lorido, L; Gelos, U

Synchronized populations of diploid yeast were exposed to uv light and their survival thereafter upon immediate plating (IP) and after liquid holding (LH) treatment in the presence and absence of caffeine was examined. These cells were found to be most resistant to uv light during early budding (G$sub 2$ period). The effect of LH is positive throughout the cell cycle and is dependent on the radiosensitivity of the cells upon IP. Caffeine-sensitive and caffeine- insensitive components of dark repair were demonstrated. The uv light responses of logarithmic growing and synchronized populations were compared with x-ray responses of the same strain analyzed under the same conditions in a previous work. The pattern of variation in sensitivity throughout the cell cycle and the ability to recover are qualitatively similar. The caffeine-insensitive component of repair has a similar efficiency in uv and x-irradiated G$sub 1$ cells, increasing in uv-irradiated cells after the beginning of the DNA synthetic period and during the G$sub 2$ period. The findings observed under IP conditions are consistent with a model already proposed which requires the repair efficiency to oscillate during the cell cycle. The results suggest that repair pathways for lethal uv damage may share some common steps with those for x-ray damage. (auth)

• Research Organization: Universidad de la Republica, Montevideo
• Sponsoring Organization: USDOE
• NSA Number: NSA-33-007447
• OSTI ID: 4149064
• Journal Information: Radiat. Res., v. 63, no. 3, pp. 474-482, Other Information: Orig. Receipt Date: 30-JUN-76
• Country of Publication: United States
• Language: English

Related Subjects

N48310* -Life Sciences-Radiation Effects on Microorganisms- -Basic Studies
560131* -Biomedical Sciences
Applied Studies-Radiation Effects-Radiation Effects on Microorganisms-Basic Studies
*BIOLOGICAL REPAIR- CAFFEINE
*CAFFEINE- RADIOSENSITIVITY EFFECTS
*CELL CYCLE- RADIOSENSITIVITY
*SACCHAROMYCES CEREVISIAE- BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
COMPARATIVE EVALUATIONS
LETHAL IRRADIATION
SURVIVAL TIME
SYNCHRONOUS CULTURES
ULTRAVIOLET RADIATION
X RADIATION