FIG. 9.

Northern analysis for steady-state level of pre-rRNAs. The structure of the pre-rRNA and locations of oligonucleotide hybridization probes are shown on the top. W303a (RRS1, wild type [WT]) and KM129 (GAL-RRS1), cultured at 25°C in YPGal, were shifted to YPD and cultured for up to 48 h. Total RNA equivalent to cells at an optical density at 600 nm of 0.5 was used for each sample. Northern blot analysis was carried out using ³²P-labeled DNA probes: probe a (A), probe b (B), probe c (C), probe d for 18S and probe e for 25S (D), and probe for RPL28 and probe for U3 (E). (F) RNA levels were quantified using BAS-1000 (Fuji Photo Film Co.), and the ratio of the radioactivity value at each time point to that at time zero is shown.