scholarly journals The essential DNA polymerases delta and epsilon are involved in repair of UV-damaged DNA in the yeast Saccharomyces cerevisiae.

1999 ◽  
Vol 46 (2) ◽  
pp. 289-298 ◽  
Author(s):  
A Hałas ◽  
Z Policińska ◽  
H Baranowska ◽  
W J Jachymczyk
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Dna Repair ◽  
Uv Irradiation ◽  
Dna Polymerases ◽  
Relative Molecular Mass ◽  
Yeast Saccharomyces Cerevisiae ◽  
Strand Breaks ◽  
Single Strand Breaks ◽  
Mutant Strains ◽  
Cellular Dna

We have studied the ability of yeast DNA polymerases to carry out repair of lesions caused by UV irradiation in Saccharomyces cerevisiae. By the analysis of postirradiation relative molecular mass changes in cellular DNA of different DNA polymerases mutant strains, it was established that mutations in DNA polymerases delta and epsilon showed accumulation of single-strand breaks indicating defective repair. Mutations in other DNA polymerase genes exhibited no defects in DNA repair. Thus, the data obtained suggest that DNA polymerases delta and epsilon are both necessary for DNA replication and for repair of lesions caused by UV irradiation. The results are discussed in the light of current concepts concerning the specificity of DNA polymerases in DNA repair.

scholarly journals DNA polymerases required for repair of UV-induced damage in Saccharomyces cerevisiae.

1995 ◽  
Vol 15 (4) ◽  
pp. 2173-2179 ◽  
Author(s):  
M E Budd ◽  
J L Campbell
Keyword(s):  
Dna Polymerase ◽  
Dna Polymerases ◽  
Dna Polymerase Delta ◽  
Weight Changes ◽  
Repair Synthesis ◽  
Strand Breaks ◽  
Single Strand Breaks ◽  
Quadruple Mutant ◽  
Cellular Dna ◽  
Repair Defect

The ability of yeast DNA polymerase mutant strains to carry out repair synthesis after UV irradiation was studied by analysis of postirradiation molecular weight changes in cellular DNA. Neither DNA polymerase alpha, delta, epsilon, nor Rev3 single mutants evidenced a defect in repair. A mutant defective in all four of these DNA polymerases, however, showed accumulation of single-strand breaks, indicating defective repair. Pairwise combination of polymerase mutations revealed a repair defect only in DNA polymerase delta and epsilon double mutants. The extent of repair in the double mutant was no greater than that in the quadruple mutant, suggesting that DNA polymerases alpha and Rev3p play very minor, if any, roles. Taken together, the data suggest that DNA polymerases delta and epsilon are both potentially able to perform repair synthesis and that in the absence of one, the other can efficiently substitute. Thus, two of the DNA polymerases involved in DNA replication are also involved in DNA repair, adding to the accumulating evidence that the two processes are coupled.

A Saccharomyces cerevisiae phleomycin-sensitive mutant, phl40, is defective in the RAD6 DNA repair gene

1996 ◽  
Vol 42 (12) ◽  
pp. 1263-1266 ◽  
Author(s):  
Chuan Hua He ◽  
Jean-Yves Masson ◽  
Dindial Ramotar
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Dna Repair ◽  
Anticancer Agent ◽  
Radiation Treatment ◽  
Dna Lesions ◽  
Exact Nature ◽  
Repair Gene ◽  
Yeast Saccharomyces Cerevisiae ◽  
Dna Repair Gene ◽  
Cellular Dna

The antibiotic bleomycin is used as an anticancer agent for treating a variety of tumours. The antitumour effect of bleomycin is related to its ability to produce lesions such as apurinic/apyrimidinic sites and single- and double-strand breaks in the cellular DNA. Phleomycin is a structurally related form of bleomycin, but it is not used as an anticancer agent. While phleomycin can also damage DNA, neither the exact nature of these DNA lesions nor the cellular process that repairs phleomycin-induced DNA lesions is known. As a first step to understand how eukaryotic cells provide resistance to phleomycin, we used the yeast Saccharomyces cerevisiae as a model system. Several phleomycin-sensitive mutants were generated following γ-radiation treatment and among these mutants, phl40 was found to be the most sensitive to phleomycin. Molecular analysis revealed that the mutant phl40 harbored a mutation in the DNA repair gene RAD6. Moreover, a functional copy of the RAD6 gene restored full phleomycin resistance to strain phl40. Our findings indicate that the RAD6 protein is essential for yeast cellular resistance to phleomycin.Key words: yeast, phleomycin, DNA repair, RAD6.

scholarly journals Multiple Pathways of Recombination Induced by Double-Strand Breaks in Saccharomyces cerevisiae

1999 ◽  
Vol 63 (2) ◽  
pp. 349-404 ◽  
Author(s):  
Frédéric Pâques ◽  
James E. Haber
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Dna Repair ◽  
Genetic Recombination ◽  
Double Strand Breaks ◽  
Molecular Models ◽  
Yeast Saccharomyces Cerevisiae ◽  
Strand Breaks ◽  
The Past ◽  
Biochemical Studies

SUMMARY The budding yeast Saccharomyces cerevisiae has been the principal organism used in experiments to examine genetic recombination in eukaryotes. Studies over the past decade have shown that meiotic recombination and probably most mitotic recombination arise from the repair of double-strand breaks (DSBs). There are multiple pathways by which such DSBs can be repaired, including several homologous recombination pathways and still other nonhomologous mechanisms. Our understanding has also been greatly enriched by the characterization of many proteins involved in recombination and by insights that link aspects of DNA repair to chromosome replication. New molecular models of DSB-induced gene conversion are presented. This review encompasses these different aspects of DSB-induced recombination in Saccharomyces and attempts to relate genetic, molecular biological, and biochemical studies of the processes of DNA repair and recombination.

KGF facilitates repair of radiation-induced DNA damage in alveolar epithelial cells

1997 ◽  
Vol 272 (6) ◽  
pp. L1174-L1180 ◽  
Author(s):  
M. Takeoka ◽  
W. F. Ward ◽  
H. Pollack ◽  
D. W. Kamp ◽  
R. J. Panos
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Epithelial Cells ◽  
Dna Polymerase ◽  
Dna Polymerases ◽  
Dna Strand Breaks ◽  
Strand Breaks ◽  
Alveolar Epithelial ◽  
Radiation Induced ◽  
Dna Strand

Administration of exogenous keratinocyte growth factor (KGF) prevents or attenuates several forms of oxidant-mediated lung injury. Because DNA damage in epithelial cells is a component of radiation pneumotoxicity, we determined whether KGF ameliorated DNA strand breaks in irradiated A549 cells. Cells were exposed to 137Cs gamma rays, and DNA damage was measured by alkaline unwinding and ethidium bromide fluorescence after a 30-min recovery period. Radiation induced a dose-dependent increase in DNA strand breaks. The percentage of double-stranded DNA after exposure to 30 Gy increased from 44.6 +/- 3.5% in untreated control cells to 61.6 +/- 5.0% in cells cultured with 100 ng/ml KGF for 24 h (P < 0.05). No reduction in DNA damage occurred when the cells were cultured with KGF but maintained at 0 degree C during and after irradiation. The sparing effect of KGF on radiation-induced DNA damage was blocked by aphidicolin, an inhibitor of DNA polymerases-alpha, -delta, and -epsilon and by butylphenyl dGTP, which blocks DNA polymerase-alpha strongly and polymerases-delta and -epsilon less effectively. However, dideoxythymidine triphosphate, a specific inhibitor of DNA polymerase-beta, did not abrogate the KGF effect. Thus KGF increases DNA repair capacity in irradiated pulmonary epithelial cells, an effect mediated at least in part by DNA polymerases-alpha, -delta, and -epsilon. Enhancement of DNA repair capability after cell damage may be one mechanism by which KGF is able to ameliorate oxidant-mediated alveolar epithelial injury.

Direction of chromosome rearrangements in Saccharomyces cerevisiae by use of his3 recombinational substrates

1988 ◽  
Vol 8 (10) ◽  
pp. 4370-4380
Author(s):  
M T Fasullo ◽  
R W Davis
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acid ◽  
Chromosomal Dna ◽  
Yeast Saccharomyces Cerevisiae ◽  
Coding Sequences ◽  
Mutant Strains ◽  
Genetic Techniques ◽  
Orthogonal Field ◽  
His3 Gene ◽  
Tandem Duplications

We used the his3 recombinational substrates (his3 fragments) to direct large interchromosomal (translocations) and intrachromosomal (deletions and tandem duplications) rearrangements in the yeast Saccharomyces cerevisiae. In strains completely deleted for the wild-type HIS3 gene, his3 fragments, one containing a deletion of 5' amino acid coding sequences and the other containing a deletion of 3' amino acid coding sequences, were first placed at preselected sites by homologous recombination. His+ revertants that arose via spontaneous mitotic recombination between the two his3 fragments were selected. This strategy was used to direct rearrangements in both RAD52+ and rad52 mutant strains. Translocations occurred in the RAD52+ genetic background and were characterized by orthogonal field alternating gel electrophoresis of yeast chromosomal DNA and by standard genetic techniques. An unexpected translocation was also identified in which HIS3 sequences were amplified. Two types of tandem duplications of the GAL(7, 10, 1) locus were also directed, and one type was not observed in rad52 mutants. Recombination mechanisms are discussed to account for these differences.

Mammalian DNA Repair and the Cellular DNA Polymerases

2003 ◽  
pp. 161-180 ◽  
Author(s):  
Samuel H. Wilson ◽  
Rakesh K. Singhal
Keyword(s):  
Dna Repair ◽  
Dna Polymerases ◽  
Cellular Dna

scholarly journals Cytogenetic markers, DNA single-strand breaks, urinary metabolites, and DNA repair rates in styrene-exposed lamination workers.

2004 ◽  
Vol 112 (8) ◽  
pp. 867-871 ◽  
Author(s):  
Pavel Vodicka ◽  
Jarno Tuimala ◽  
Rudolf Stetina ◽  
Rajiv Kumar ◽  
Paola Manini ◽  
...  
Keyword(s):  
Dna Repair ◽  
Urinary Metabolites ◽  
Single Strand ◽  
Strand Breaks ◽  
Single Strand Breaks

scholarly journals A CAF-1–PCNA-Mediated Chromatin Assembly Pathway Triggered by Sensing DNA Damage

2000 ◽  
Vol 20 (4) ◽  
pp. 1206-1218 ◽  
Author(s):  
Jonathan G. Moggs ◽  
Paola Grandi ◽  
Jean-Pierre Quivy ◽  
Zophonías O. Jónsson ◽  
Ulrich Hübscher ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Single Strand ◽  
Chromatin Assembly ◽  
Checkpoint Control ◽  
Free System ◽  
Strand Breaks ◽  
Assembly Pathway ◽  
Single Strand Breaks ◽  
Damaged Dna

ABSTRACT Sensing DNA damage is crucial for the maintenance of genomic integrity and cell cycle progression. The participation of chromatin in these events is becoming of increasing interest. We show that the presence of single-strand breaks and gaps, formed either directly or during DNA damage processing, can trigger the propagation of nucleosomal arrays. This nucleosome assembly pathway involves the histone chaperone chromatin assembly factor 1 (CAF-1). The largest subunit (p150) of this factor interacts directly with proliferating cell nuclear antigen (PCNA), and critical regions for this interaction on both proteins have been mapped. To isolate proteins specifically recruited during DNA repair, damaged DNA linked to magnetic beads was used. The binding of both PCNA and CAF-1 to this damaged DNA was dependent on the number of DNA lesions and required ATP. Chromatin assembly linked to the repair of single-strand breaks was disrupted by depletion of PCNA from a cell-free system. This defect was rescued by complementation with recombinant PCNA, arguing for role of PCNA in mediating chromatin assembly linked to DNA repair. We discuss the importance of the PCNA–CAF-1 interaction in the context of DNA damage processing and checkpoint control.

Sign in / Sign up

Export Citation Format

Share Document