Figure 3. E2F1 and Jab1/CSN5 co-occupy mitotic and apoptotic target but not DNA replication gene promoters. E2F1 and Jab1 binding to E2F1 target gene promoters was assessed using chromatin IP (ChIP). REF52 cells were cross-linked with formaldehyde, chromatin was isolated and sonicated and immunoprecipitated with anti-E2F1 (A) or anti-Jab1/CSN5 (B) antisera. Precipitated DNA was analyzed by SYBR green real-time PCR using primers and results are displayed as a comparative fold-induced binding from precipitate using no antibody vs. experimental antibody. Specific promoters analyzed are listed below each graph. ChIP results are separated into two parts in section A because of the very different scales for the two classes of genes. (C) Serum deprived quiescent REF52 cells were transfected with E2F1 or vector control. Chromatin was isolated and immunoprecipitated with anti-E2F1 or anti-Jab1 antisera.