Figure 4.

Transcriptional induction of RNR2, RNR3, and UBI4 after treatment with 200 mM HU in an hrr25Δ strain. (A) RNA was isolated from the strains indicated at the top of each panel after treatment with HU as described in the legend to Fig. 3. Total RNA was extracted and Northern hybridization analysis was performed with the probes indicated to the left. (B) PhosphorImager analysis of the Northern blots shown in A. The RNA levels of RNR2, RNR3, and UBI4 relative to ACT1 were determined and plotted versus time after HU addition.