From the Cover: mitotic gene conversion events induced in G1-synchronized yeast cells by gamma rays are similar to spontaneous conversion events.
In a previous study, we mapped spontaneous mitotic reciprocal crossovers (RCOs) in a 120-kb interval of chromosome V of Saccharomyces cerevisiae. About three-quarters of the crossovers were associated with gene conversion tracts. About 40% of these conversion tracts had the pattern expected as a consequence of repair of a double-stranded DNA break (DSB) of an unreplicated chromosome. We test this hypothesis by examining the crossovers and gene conversion events induced by gamma irradiation in G1- and G2-arrested diploid yeast cells. The gene conversion patterns of G1-irradiated cells (but not G2-irradiated cells) mimic conversion events associated with spontaneous RCOs, confirming our previous conclusion that many spontaneous crossovers are initiated by a DSB on an unreplicated chromosome.
Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC 27710, USA.
Phoebe S
PS
Lee
Thomas D
TD
Petes
D002470:Cell Survival; D002842:Chromatids / Q000648:ultrastructure; D002874:Chromosome Mapping; D004247:DNA / Q000528:radiation effects*; D004249:DNA Damage; D004171:Diploidy; D016193:G1 Phase; D016195:G2 Phase; D005720:Gamma Rays; D005785:Gene Conversion; D007700:Kinetics; D019656:Loss of Heterozygosity; D008938:Mitosis; D008957:Models, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000528:radiation effects
D004247:DNA