Expression of wild-type and mutant C/EBPϵ proteins. Jurkat cells were transfected with either wild-type or mutant C/EBPϵ expression vectors alone. Forty-eight hours after transfection cells were harvested for total and nuclear protein extraction. Western immunoblot analysis was carried out using an antibody specific for C/EBPϵ. (A) Total protein extract. (B) Nuclear protein extract.