Figure 6. PU.1–regulated targets change in differentiated human myeloid cell types.

(A) Undifferentiated HL-60 were treated with a PU.1 siRNA or control siRNA. HL-60 cells were then induced to differentiate into macrophages, monocytes, and neutrophils and harvested 24-hours post siRNA treatment. Undifferentiated HL-60 cells were also measured following siRNA treatment for 24 hours. (B) mRNA fold change (Log₂ transformed) between PU.1^KD and siControl is shown for each PU.1 target from our gene regulatory network. Differential expression significance was calculated using biological replicates (Supplemental Methods). * p-value < 0.05; ** p-value < 0.01. (C) Chromatin accessibility fold change (Log₂) between PU.1^KD and control conditions is shown for PU.1 associated elements and chromatin elements near regulators. Distance of chromatin element to start of each gene is indicated. Differential accessibility is indicated * p-value < 0.05; ** p-value < 0.01. (D) Genome-view of the PU.1 sub-circuitry in myeloid cells. PU.1 regulatory interactions are specified as red arrows in our circuit diagram. Colored boxes underneath gene names indicate the cell-type origin of the PU.1 mediated interaction. Black asterisk indicates a change in PU.1 target by gene expression only. Blue asterisk indicates a change in PU.1 target by chromatin accessibility only. Orange asterisk indicates a change in PU.1 target detected by both gene expression and chromatin accessibility. Significance is indicated by a p-value < 0.05.