| Title: | Ionizing irradiation effects on S-phase in checkpoint mutants of the yeast Saccharomyces cerevisiae |
| Author(s): | King WR; Rowley R; Schroeder AL; |
| Address: | "School of Molecular Biosciences, Washington State University, Pullman, WA 99164-4234, USA" |
| DOI: | 10.1007/s00294-002-0361-4 |
| ISSN/ISBN: | 0172-8083 (Print) 0172-8083 (Linking) |
| Abstract: | "In mammalian cells, gamma-irradiation activates checkpoint controls to delay entry into, or passage through S-phase, while chronic exposure to methyl methanesulfonate or hydroxyurea causes a similar delay in yeast. In yeast, at least five genes are involved: RAD9, RAD17, RAD24, RAD53 and MEC1, a homologue of ATM. Here, using flow cytometry analysis and alkaline sucrose gradient centrifugation of labeled, newly made DNA, we demonstrate, in synchronized RAD wild-type Saccharomyces cerevisiae cells, that: (1) gamma-irradiation at START delays entry into S-phase, (2) irradiation shortly before or during early S-phase delays completion of S-phase and (3) the latter response is largely a consequence of replicon initiation inhibition. The delay produced by irradiation during early S-phase depends on the function of the checkpoint genes RAD9, RAD17, RAD24, RAD53, MEC1 and MEC3. However, at least four, RAD17, RAD53, MEC1, MEC3, are not needed to delay S-phase progression when cells are irradiated shortly before S-phase begins" |
| Keywords: | "DNA/biosynthesis G1 Phase/radiation effects Genes, cdc/*radiation effects Mating Factor Peptides Radiation, Ionizing Replicon/radiation effects S Phase/*radiation effects Saccharomyces cerevisiae/*radiation effects;" |
| Notes: | "MedlineKing, William R Rowley, Roy Schroeder, Alice L eng 2S7RR079725/RR/NCRR NIH HHS/ CA40254/CA/NCI NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 2003/03/04 Curr Genet. 2003 Mar; 42(6):313-21. doi: 10.1007/s00294-002-0361-4. Epub 2003 Feb 1" |
