Fig. 2. pds5 cells are sensitive to DNA damaging agents, but not to inhibition of DNA replication. (A) Strains HM123 (pds5⁺), pds5-GFP and pds5 were tested for sensitivity to UV. Colony numbers were counted after four days growth at 30°C following exposure to the indicated UV doses on YE agar plates, and were expressed as a percentage of the number of colonies seen after mock irradiation (upper panel). Cellular and nuclear morphologies of HM123 (pds5⁺) and pds5 strains were determined by fluorescence microscopy of DAPI-stained cells 12 hours after exposure to 150 Jm^-2 UV (lower panels; Bar, 10 µm). (B) Tenfold serial dilutions of HM123 (pds5⁺) and the other strains indicated were spotted onto YE agar plates containing 0.005% MMS, 5 µg/ml bleomycin or neither drug (control). Plates were photographed after 3-5 days incubation at 30°C. (C) The strains indicated were streaked in the positions shown onto YE agar (control) or YE agar containing 10 mM HU. Plates were photographed after 4 days growth at 30°C.