Saccharomyces cerevisiae RAD53 (CHK2) but not CHK1 is required for double-strand break-initiated SCE and DNA damage-associated SCE after exposure to X rays and chemical agents.
Saccharomyces cerevisiae RAD53 (CHK2) and CHK1 control two parallel branches of the RAD9-mediated pathway for DNA damage-induced G(2) arrest. Previous studies indicate that RAD9 is required for X-ray-associated sister chromatid exchange (SCE), suppresses homology-directed translocations, and is involved in pathways for double-strand break repair (DSB) repair that are different than ... those controlled by PDS1. We measured DNA damage-associated SCE in strains containing two tandem fragments of his3, his3-Delta5' and his3-Delta3'::HOcs, and rates of spontaneous translocations in diploids containing GAL1::his3-Delta5' and trp1::his3-Delta3'::HOcs. DNA damage-associated SCE was measured after log phase cells were exposed to methyl methanesulfonate (MMS), 4-nitroquinoline 1-oxide (4-NQO), UV, X rays and HO-induced DSBs. We observed that rad53 mutants were defective in MMS-, 4-NQO, X-ray-associated and HO-induced SCE but not in UV-associated SCE. Similar to rad9 pds1 double mutants, rad53 pds1 double mutants exhibited more X-ray sensitivity than the single mutants. rad53 sml1 diploid mutants exhibited a 10-fold higher rate of spontaneous translocations compared to the sml1 diploid mutants. chk1 mutants were not deficient in DNA damage-associated SCE after exposure to DNA damaging agents or after DSBs were generated at trp1::his3-Delta5'his3-Delta3'::HOcs. These data indicate that RAD53, not CHK1, is required for DSB-initiated SCE, and DNA damage-associated SCE after exposure to X-ray-mimetic and UV-mimetic chemicals.
Mesh Terms:
4-Nitroquinoline-1-oxide, Cell Cycle Proteins, DNA Breaks, Double-Stranded, DNA Damage, Deoxyribonucleases, Type II Site-Specific, Methyl Methanesulfonate, Mutagens, Protein Kinases, Protein-Serine-Threonine Kinases, Recombination, Genetic, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sister Chromatid Exchange, Ultraviolet Rays, X-Rays
4-Nitroquinoline-1-oxide, Cell Cycle Proteins, DNA Breaks, Double-Stranded, DNA Damage, Deoxyribonucleases, Type II Site-Specific, Methyl Methanesulfonate, Mutagens, Protein Kinases, Protein-Serine-Threonine Kinases, Recombination, Genetic, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sister Chromatid Exchange, Ultraviolet Rays, X-Rays
DNA Repair (Amst.)
Date: Nov. 21, 2005
PubMed ID: 16039914
View in: Pubmed Google Scholar
Download Curated Data For This Publication
20919
Switch View:
- Interactions 3