Figure 3

Comparison of re-replication between the wild-type and checkpoint-mutant strains. DNA re-replication profiles from the wild-type (dark green), cds1 Δ (light blue), and rad3 Δ (dark red) strains induced for Cdc18* over-expression are shown for chromosomes 1 (A), 2 (B), and 3 (C). Median probe values across 5 neighboring probes from the 21- and 25-hour data sets were used to smooth data into one composite DNA re-replication profile for each strain along each chromosome. In order to view all three re-replication profiles for a chromosome, the cds1 Δ data are offset on the Y-axis by +1.0 and the rad3 Δ data are offset by +2.0. Centromeres are indicated by yellow squares. The mating-type locus on chromosome 2 is marked by a light grey vertical rectangle. Plotted as solid circles below each chromosome are origins which fired with greater efficiency in the cds1 Δ and rad3 Δ (purple) or wild-type (green) strains when cells were treated with HU in the previous study by Mickle et al. [31]. Notice that all of the large amplified regions found in wild-type cells are also found in cds1 Δ and rad3 Δ cells. rad3 Δ cells have additional small amplified regions which are not present in the wild-type or cds1 Δ strains. Thus checkpoint proteins do not affect origin selection during re-replication as they do during replication.