Dominant negative Cul1 interacts with E2F . (A) Wild-type wing. (B) Small wing due to dominant negative Cul1 expression (MS1096/Y;UAS-mCul1/+). (C) This phenotype is completely suppressed when E2F levels are reduced by 50% (MS1096/Y;UAS-mCul1/E2F91). (D) Increased levels of E2F from a transgene under the control of the HSP70 promoter enhance the small wing phenotype (MS1096/Y;UAS-mCul1/hs-E2F) after heat shock treatment. (E) Discs overexpressing mCul1 have a high level of cell death (MS1096/Y;UAS-mCul1/+). (F) Cell death is reduced when E2F levels are reduced (MS1096/Y;UAS-mCul1/E2F7172).