FIG. 3.

Poly(A)⁺ RNA levels. (A) Cultures were grown in YPAD to an OD₆₀₀ of approximately 0.3 and then shifted to 37°C. Aliquots were removed prior to the shift (0 h) and after 1, 2, and 4 h at 37°C, and RNA was isolated by acid-phenol extraction. Ten micrograms of total RNA was spotted onto nitrocellulose, and poly(A)⁺ RNA was detected by probing with a ³²P-labeled dT₂₀ probe. (B) Quantification. Spots were analyzed using a phosphorimager. The percentage of wild-type (WT) levels was determined by comparing the counts in each spot with those in the wild-type spot from 0 h. The taf90-2 strain (#) is a previously described noncogenic temperature-sensitive strain used as a control (2). The relative levels of mRNA in the mutants versus the wild type varied between 5 and 15% between experiments, but most points varied by less than 10%.