Regulation of FLT3 expression via the SP1/NF-κB(p65) complex. (A) SP1 and NF-κB(p65) binding sites in the promoter region of the FLT3 gene. (B) EMSA assays of the 2 identified binding sites for SP1 and NF-κB(p65), demonstrating specific binding of SP1 to the first site and binding of NF-κB(p65) to both sites using specific antibody to supershift the DNA-protein complexes. (C) Chromatin (ChIP) for the region containing binding sites of SP1 and of NF-κB(p65). (D) Luciferase promoter activity reporter assay including 700 bp of the promoter region of the FLT3 gene containing all identified SP1 and NF-κB(p65) binding sites, demonstrating increased activity after cotransfection with constructs to overexpress SP1 or NF-κB(p65) and decreased activity after siRNA mediated knockdown of SP1 and NFκB(p65). EV indicates empty vector; and sc, scramble oligo.