Motif conservation and motif score classes of bound and non-bound PU.1 consensus sites. (A) Histogram of average per-nucleotide vertebrate conservation (PhastCons) surrounding non-bound motifs, HPC-specific motifs (relative to MO), all HPC-bound motifs, MO-specific motifs (relative to HPC), all MO-bound motifs, MO-specific motifs (relative to MAC), all MAC-bound motifs and MAC-specific motifs (relative to MO), as indicated by coloring. (B) Combined bean and box plot showing the distribution of motif log-odds scores of annotated PU.1 motifs (white boxes) or best scoring motifs within total (blue boxes) or cell type-specific PU.1 peaks (light blue boxes). Solid bars of boxes display the interquartile ranges (25–75%) with an intersection as the median; whiskers represent max/min values. Significantly different motif score distributions in pairwise comparisons are indicated (***P < 0.001, Mann–Whitney U-test, two-sided). The detection threshold is indicated by the dotted line.