FIG. 3.
Sedimentation in alkaline sucrose gradients of nuclear DNA from cells incubated for different periods following UV irradiation with 2.5 J/m2. The rad1Δ (A) and rad1Δ pol30-119 (B) strains (YR1-65 and YR1-131, respectively) were UV irradiated and then pulse labeled with [3H]uracil for 15 min followed by a 30-min (▵) or 6-h (•) chase in high-uracil medium before conversion to spheroplasts and sedimentation of DNA in alkaline sucrose gradients. Unirradiated cells pulse labeled for 15 min and chased for 6 h in high-uracil medium are indicated (○).