FIGURE 3.

18S rRNA synthesis is impaired in strains depleted of Utp10 and Utp20, and aberrant pre-rRNAs are stabilized in the absence of Trf5p. Cells were pregrown on galactose medium and transferred to glucose medium. Total RNA was extracted at the times indicated and analyzed by Northern blotting. (A) Northern hybridization of high molecular weight RNAs separated on an 1.2% agarose/glyoxal gel. (B) Northern hybridization of low molecular weight RNAs separated on an 8% polyacrylamide/8 M urea gel. Oligonucleotides used for Northern hybridizations are indicated on the right of each panel.