Induction of β major globin and Fog1 by GATA-1. (A) Messenger RNA levels in G1E-ER4 cells predicted by microarray experiments. (B) Messenger RNA levels quantitated by real-time polymerase chain reaction (PCR) in G1E-ER4 cells overexpressing bcl-x_L to overcome cycloheximide-induced death. Each data point represents 6 separate PCR reactions in 2 independent experiments. Cycloheximide (0.5 mM) was added as indicated. Note that the magnitude of β globin RNA induction appears to be underestimated by the microarrays, as was also observed for α globin (Figure 4). This is likely due to saturation of the microarray system by these abundant transcripts. Error bars indicate standard deviations for triplicate experiments.