Hemogen /BRG1 cooperativity modulates promoter and enhancer activation during erythropoiesis [ChIP-seq]

To determine hemogen function in regulatory elements, ChIPmentation was performed in both WT and hemogen KO K562 cells and H3K27ac enrichment was significantly reduced at both promoters and enhancers in loss of hemogen. To identify direct targets and the regulatory role of hemogen in murine erythroid gene expression, hemogen and BRG1 ChIP-seq was performed in the WT and hemogen KO E14.5 fetal liver cells. Hemogen was found enriched in GATA1/TAL1 binding motifs and equally bind to the promoter and potential enhancer region. Notably, BRG1 occupancy (95%) was almost completely coincident with hemogen binding sites and loss of hemogen greatly impaired the BRG1 occupancy at both erythroid promoters and enhancers. ChIPmentation was performed using H3k27ac antibody to identify promoter and enhancer activity. ChIP-seq was performed in the E14.5 fetal liver cells to identify global occupancy of hemogen, BRG1 and H3K27ac at erythroid genes.