The Lyl1 core promoters depend on conserved Ets, GATA, and GGCC motifs, and the Lyl1 promoter proximal region is bound in vivo by Ets and GATA factors. (A) The 2 Ets binding sites and the GGCC motif are important for activity of the Lyl1P1 promoter. Shown are the results from reporter assays of a series of Lyl1P1 promoter mutation constructs in which either the 2 Ets binding sites (P1_e1 and P1_E2) or the GGCC motif (P1_GC) were mutated. Constructs were transfected into L8057, 416B, and MS1 cells as described in Figure 2. (B) Ets and GATA binding sites are necessary for activity of the Lyl1P2 promoter. Shown are the results from reporter assays of Lyl1P2 promoter constructs in which either all 3 Ets (P2_E345) or the 2 GATA binding sites (P2_G12) were mutated. Constructs were transfected into L8057, 416B, and MS1 cells as described in Figure 2. (C) Fli-1, Elf-1, GATA2, Erg, and PU.1 bind the Lyl1 proximal promoter region. Chromatin immunoprecipitation assays were performed in L8057, 416B, and MS1 cell lines with anti-Fli1, -Elf2, -GATA2, -Erg, -PU.1, -GATA2, –acetylated lysine K9 of histone H3, and control IgG antibodies. The DNA content of the immunoprecipitates was analyzed by real-time PCR. The level of enrichment with each antibody was normalized to the levels obtained with the control IgG and plotted as fold increase over the level of enrichment at a control region (see “Materials and methods”). MS1 cells do not express PU.1. Error bars indicate SD.