Fig. 5. Genetic requirements for G1 arrest. f-arrested cells were released after increasing doses of irradiation. f/nocodazole-trapping media was added at the indicated time points, and cells were incubated 90 minutes before fixation. (For wt, rad9 and rad17: , 0 Gy; , 100 Gy; , 200 Gy; , 400 Gy. For rad52 (, 0 Gy; , 50 Gy; , 100 Gy; , 200 Gy)). For comparisons, the solid line shows the percentage of 1N of the starting population and the hatched line marks 50% 1N. rad9, rad17 double mutants were indistinguishable from either single mutant in this assay (data not shown).