Identification of IFN-α–inducible Stat activation by GDAC. Actively growing 32D and FDCP-2 cells were incubated with or without IFNα for 15 minutes. Cytoplasmic extracts were prepared and analyzed for DNA-binding STAT complexes using GDAC. Eluates from genomic DNA were resolved by SDS-PAGE (7%) and after Western blotting, probed with antibodies to Stat-1, Stat-2, and Stat-3. IFN-α–induced Stat proteins are indicated by arrows.