Heteroduplex repair as an intermediate step of uv mutagenesis in yeast

Journal Article · Thu May 01 00:00:00 EDT 1980 · Genetics; (United States)

OSTI ID:5157688

Eckardt, F; Teh, S J; Haynes, R H

We have measured uv-induced mutation frequencies in yeast in a forward, nonselective assay system by scoring white adex ade2 double auxotrophs among parental red-pigmented ade2 clones. The frequencies of sectored and pure mutant clones were determined separately. In excision-defective strains carrying the genes rad1-1, rad3-2 and rad4-4, as well as in the double mutants, rad 1-1 rad 3-2 and rad 1-1 rad 4-4, considerably more sectored than pure clones are induced in the low-dose range; in repair-competent strains, pure mutant clones substantially outnumber the sectored clones. These results can be explained on the basis of known differences in the timing of error-prone repair during the cell division cycle; that is, we assume that error-prone repair occurs primarily before replication in RAD wild-type strains but after replication in excision-deficient mutants. It has been suggested that excision deficiency has a pleiotropic effect on heteroduplex repair and nucleotide excision repair; however, the high percentage (36.6%) of half-sectored clones found in the rad1-1 strain is hard to reconcile with this hypothesis. We propose that heteroduplex repair occurs subsequent to error-prone repair in both excision-proficient and excision-deficient strains.

• Research Organization: York Univ., Toronto, Canada
• OSTI ID: 5157688
• Journal Information: Genetics; (United States), Vol. 95:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
BIOLOGICAL REPAIR
RADIOSENSITIVITY EFFECTS
MUTATIONS
RADIOINDUCTION
SACCHAROMYCES CEREVISIAE
GENETIC RADIATION EFFECTS
ULTRAVIOLET RADIATION
MUTAGENESIS
CELL CYCLE
DNA
IRRADIATION
MUTATION FREQUENCY
TIME DEPENDENCE
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
ELECTROMAGNETIC RADIATION
FUNGI
GENETIC EFFECTS
MICROORGANISMS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
PLANTS
RADIATION EFFECTS
RADIATIONS
RECOVERY
REPAIR
SACCHAROMYCES
YEASTS
560131* - Radiation Effects on Microorganisms- Basic Studies- (-1987)
550400 - Genetics
550700 - Microbiology