(A) Northern blot analysis of IFN-α–treated KT-1 cells. The blot was transferred to nitrocellulose and successfully hybridized to the indicated probes. KT-1 cells were exposed to IFN-α (1,000 U/mL) for indicated times. Time points were 6 and 24 hours' exposure to IFN-α. (B) Northern blot analysis of IFN-α–treated K562 cells. K562 cells were exposed to IFN-α (1,000 U/mL) for 24 hours. (C) Northern blot analysis of IFN-γ–treated KT-1 cells. KT-1 cells were exposed to IFN-γ (1,000 U/mL) for indicated times. Time points were 6 and 24 hours' exposure to IFN-γ.