Figure 5. Confirmation of Ets1 and Elk1 binding to the proximal promoter of the CIP2A gene. Nuclear extracts (9 μg) from ECC-1 were incubated with WT probe (−138 to−107) from the CIP2A gene along with 2 μg of antibody directed toward Ets1, Elk1, or Ets1 and Elk1 together. The negative control consisted of rabbit-pre-immune control IgG. The formation of DNA–protein complexes is designated by solid arrows. The experiment was repeated twice with similar results.