Figure 3.

The mre11-S499P and rad50-A78T mutations suppress the adaptation defect of sae2Δ cells. (A) Rad53 phosphorylation during adaptation. Exponentially growing YEPR cultures were transferred to YEPRG (time zero), followed by western blot analysis with anti-Rad53 antibodies. (B) Adaptation assay. YEPR G1-arrested cell cultures of the strains in (A) were plated on galactose-containing plates (time zero). At the indicated time points, 200 cells for each strain were analyzed to determine the frequency of large budded cells (two cells) and of cells forming microcolonies of more than two cells. (C, D) Drop test. Exponentially growing cells were serially diluted (1:10) and each dilution was spotted out onto YEPD plates with or without HU, MMS and CPT at the indicated concentrations. All strains carried SML1 deletion to keep mec1Δ cells viable.