Fig. 3. Analysis of pre-rRNA processing. (A) Northern analysis. Lanes 1 and 2, wild-type strain in RGS medium and 24 h after transfer to glucose; lanes 3–7, GAL::nop15 strain in RGS medium and after transfer to glucose medium for the times indicated. (B) Northern analysis. Lane 1, wild-type strain 24 h after transfer to glucose; lanes 2–7, GAL::nop15 strain in RGS medium and after transfer to glucose medium for the times indicated. RNA was separated on a 1.2% agarose/formaldehyde gel (A) or 8% polyacrylamide/urea gel (B). Probe names are indicated in parentheses on the left. (C) Primer extension using oligo 006, which hybridizes within ITS2, 3′ to site C₂ (the 3′ end of the 7S pre-rRNA). Primer extension stops at sites A₂, A₃, B_1S and B_1L show levels of the 27SA₂, 27SA₃, 27SB_S and 27SB_L pre-rRNAs, respectively. Lanes 1 and 2, wild-type strain in RGS medium and 20 h after transfer to glucose medium; lanes 3 and 4, GAL::nop15 strain in RGS medium and 20 h after transfer to glucose medium.