(C-G) ssDNA repair efficiency of the indicated TS mutants as determined from the maximal and final percentages of cells with Rad52 foci during the time course (right panels). Cells were synchronized in G1 and released into S phase in the presence of 0.033% MMS for 1 hour (60+), treated with 2.5% sodium thiosulfate to inactivate the MMS, washed and released into fresh medium for different times. They were also released into medium without MMS for 1 hour to control the formation of spontaneous Rad52-YFP foci (60-). The percentage of cells with foci at each point was normalized to the highest value of the wild type, taken as 100 (left panels). Cell cycle progression was determined by cell sorting. The mean and SEM of 3 (wild type, rad18∆, mms2∆, rad51∆, rad57∆, rad54∆), 4 (pol30-K164R) and 5 (rad5∆) independent experiments are shown. Statistically significant differences according to an unpaired two-tailed Student's t-test are shown, where three asterisks represent p-values <0.001. 