Molecular mechanisms of pyrimidine dimer excision in Saccharomyces cerevisiae: incision of ultraviolet-irradiated deoxyribonucleic acid in vivo

Journal Article · Fri May 01 00:00:00 EDT 1981 · J. Bacteriol.; (United States)

OSTI ID:6337437

Reynolds, R J; Friedberg, E C

A group of genetically related ultraviolet (uv)-sensitive mutants of Saccharomyces cerevisiae has been examined in terms of their survival after exposure to uv radiation, their ability to carry out excision repair or pyrimidine dimers as measured by the loss of sites (pyrimidine dimers) sensitive to a dimer-specific enzyme probe, and in terms of their ability to effect incision of their deoxyribonucleic acid (DNA) during post-uv incubation in vivo (as measured by the detection of single-strand breaks in nuclear DNA). In addition to a haploid RAD/sup +/ strain (S288C), 11 different mutants representing six RAD loci (RAD1, RAD2, RAD3, RAD4, RAD14, and RAD18) were examined. Quantitative analysis of excision repair capacity, as determined by the loss of sites in DNA sensitive to an enzyme preparation from M. luteus which is specific for pyrimidine dimers, revealed a profound defect in this parameter in all but three of the strains examined. The rad14-1 mutant showed reduced but significant residual capacity to remove enzyme-sensitive sites as did the rad2-4 mutant. The latter was the only one of three different rad2 alleles examined which was leaky in this respect. The uv-sensitive strain carrying the mutant allele rad18-1 exhibited normal loss of enzyme-sensitive sites consistent with its assignment to the RAD6 rather than the RAD3 epistatic group. All strains having mutant alleles of the RAD1, RAD2, RAD3, RAD4, and RAD14 loci showed no detectable incubation-dependent strand breaks in nuclear DNA after exposure to uv radiation. These experiments suggest that the RAD1, RAD2, RAD3, RAD4 (and probably RAD14) genes are all required for the incision of uv-irradiated DNA during pyrimidine dimer excision in vivo.

• Research Organization: Stanford Univ., CA
• DOE Contract Number: 76EV70032
• OSTI ID: 6337437
• Journal Information: J. Bacteriol.; (United States), Vol. 146:2
• 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
DNA
BIOLOGICAL REPAIR
SACCHAROMYCES CEREVISIAE
RADIOSENSITIVITY
DIMERS
GENES
GENETICS
IN VIVO
MOLECULAR STRUCTURE
MUTANTS
PYRIMIDINES
RADIATION DOSES
SURVIVAL TIME
ULTRAVIOLET RADIATION
AZINES
BIOLOGICAL RECOVERY
BIOLOGY
DOSES
ELECTROMAGNETIC RADIATION
FUNGI
HETEROCYCLIC COMPOUNDS
MICROORGANISMS
NUCLEIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PLANTS
RADIATIONS
RECOVERY
REPAIR
SACCHAROMYCES
YEASTS
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