Figure 3.

H₂O₂-mediated degradation of the 25S rRNA requires cellular response. Northern hybridization of total RNA from untreated wild-type W303 cells (A and B, lanes 1–3), fixed with 1% formaldehyde (HCHO) (A, lanes 4–6) or with 70% EtOH (B, lanes 4–6) prior to exposure to indicated concentrations of H₂O₂. Hybridization was performed with probe 007 starting at position +40 of the 25S. Asterisks designate unspecific degradation product, detectable only in RNA isolated from fixed cells (A and B lanes 4–6).