Characterization of the temporal patterns of Runx2 binding associated with osteoblastogenesis. (A) Enriched regions of Runx2 binding (MACS peaks, P ≤ 1 × 10-10) were grouped into seven clusters based on the presence (red) or absence (blue) of peaks at temporal stages of osteoblastic differentiation (left panel). In the right panel, each line illustrates intensity (base-2 logarithm of the sum of read counts per 10 million reads (mean read density)) of one peak as a range from strong occupancy (brown) to weak occupancy (violet). (B) Runx2 binding intensities of Runx2 peaks from each cluster at days 0, 9, and 28 of differentiation plotted as mean ± SEM. (C) Distribution patterns of the Runx2 peaks from each of the seven clusters (from (A)) segregated into six categories of genomic locations and compared to an equivalent number of random 100 bp regions (gray bar). (D) Representative Gene Ontology term annotation of cluster 4 (days 9 & 28) by GREAT. Each term is annotated with the observed (Obs.) number of Runx2 peaks and corresponding number of genes out of the total number of genes.