Studies of DNA repair in saccharomyces cerevisiae. I. Characterization of a new allele of RAD6. II. Investigation of events in the first cell cycle after DNA damage

Thesis/Dissertation · Sun Dec 31 23:00:00 EST 1978

DOI:https://doi.org/10.2172/5525697· OSTI ID:5525697

Douthwright-Fasse, Jane Ann ^[1]

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1. Univ. of Rochester, NY (United States)

Studies in two independent, but related, areas of DNA repair have been carried out in Saccharomyces cerevisiae; characterization of a new allele in the RAD6 gene which suggests that the gene is multifunctional, and utilization of photoreactivation as a probe of events occurring during the first cell cycle after DNA damage. Strains carrying the new allele, designated rad6-4, are as sensitive to uv and ionizing radiation as those carrying rad6-1 or rad6-3 but, unlike them, are capable of induced mutagenesis and sporulation. Although rad6-4 may well be a missense mutation, the evidence shows that it is unlikely that this phenotype is due to leakiness. Instead, the data suggest that the RAD6 gene is multifunctional. One function is necessary to recover from DNA damage in an error-free manner, and the other is concerned with mutagenic processes and sporulation. Rad6-1 and rad6-3 strains are deficient in both of these functions, while rad6-4 strains are deficient only in the error-free function. The loss of photoreversibility (LOP) of ultraviolet induced mutations to arginine independence in an excision defective strain carrying arg4-17 examines the events occurring in the first cell cycle after DNA damage. LOP is dependent upon de novo protein synthesis. LOP begins immediately after UV irradiation, before semiconservative DNA synthesis takes place, and is complete after four hours in growth medium.There is no evidence indicating whether the normal function of the protein is involved in excision repair, or in one of the two repair processes believed to be inducible; induced mutagenesis or recombinational repair.

• Research Organization: Univ. of Rochester, NY (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: EY-76-C-02-3490
• OSTI ID: 5525697
• Report Number(s): UR--3490-1790
• Country of Publication: United States
• Language: English

Related Subjects

550400* -- Genetics
550700 -- Microbiology
560112 -- Radiation Effects on Biochemicals-- In Microorganisms-- (-1987)
560131 -- Radiation Effects on Microorganisms-- Basic Studies-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BIOLOGICAL VARIABILITY
DATA
DATA FORMS
DNA
ELECTROMAGNETIC RADIATION
EXPERIMENTAL DATA
FUNGI
GENETIC EFFECTS
GENETIC RADIATION EFFECTS
GENETIC VARIABILITY
INFORMATION
IONIZING RADIATIONS
ISOLATED VALUES
MICROORGANISMS
MUTAGENESIS
MUTATIONS
NUCLEIC ACIDS
NUMERICAL DATA
ORGANIC COMPOUNDS
PHOTOREACTIVATION
PLANTS
RADIATION EFFECTS
RADIATIONS
RADIOINDUCTION
RADIOSENSITIVITY
RECOVERY
REPAIR
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
SPORES
ULTRAVIOLET RADIATION
YEASTS