FIG. 6.

Transcriptional and translational regulation of ferritin. The cumulative effects of hydrogen peroxide on ferritin H and L mRNA synthesis, IRP-1 activity, and ferritin H and L protein synthesis in BNL CL.2 cells are summarized. Ferritin protein synthesis was measured by immunoprecipitation as shown in Fig. 5; mRNA levels were measured by Northern blotting as shown in Fig. 1; and IRP activation was measured by gel mobility shift assays as shown in Fig. 5. The results were quantitated by PhosphoImager analysis, with the signal intensities at time zero being defined as 1.0. Results of two independent experiments (protein and mRNA) or three independent experiments (IRP-1) and standard errors are shown.