Fig. 4. GATA2 regulates Scl expression. (A) FACS data of hCD4⁺ (Scl⁺) cell generation. Cells were grown in serum, SR, or SR+BMP4 as indicated, were treated with or without Dox at D2, and FACS performed on D5 for Flk-1⁺ and hCD4⁺ cells. Numbers indicate total percentage of hCD4⁺ cells (Flk-1⁺hCD4⁺ and Flk-1^-hCD4⁺). (A') Summary data of five independent sets of FACS experiments showing the percentage of hCD4⁺ cells generated in each condition. Values indicate mean±s.e.m.; ^*, P<0.01 versus untreated. (B) Comparison of human SCL and mouse Scl loci. P indicates alternate promoters, and numbers indicate DNase I hypersensitive sites (Gottgens et al., 2002). Black boxes and white boxes indicate translated and untranslated exons, respectively. Vertical dashes indicate consensus (WGATAR) GATA-factor-binding sites. The bottom line indicates general locus coordinates, where 1 is the start of transcription. (C) Quantitative ChIP assays for GATA-factor occupancy of the Scl loci. Upper panel shows GATA2 occupancy, measured against a standard curve of input dilutions. Individual measurement parameters (EB day, Scl locus site) are the same as on the bottom panel. Bottom panel shows GATA-1 occupancy. Values are mean±s.e.m. for three independent experiments.