Fig. 4: Definition of the osteocyte-specific Sp7 cistrome.

a Sp7 ChIP-seq was performed in Ocy454 cells, and Sp7-binding patterns were compared between Ocy454 cells and primary osteoblasts (POB). See also Supplementary Data 3. b Genomic distribution of cell type-specific Sp7-binding sites. c Gene ontology analysis of genes linked to Ocy454 cell-specific Sp7 peaks. Sp7 associates with regulatory regions of genes linked to motor neuron axon guidance and actin filament bundle assembly. d Ocy454 cell-specific Sp7-bound enhancer peaks were analyzed for the indicated histone modifications in d3 (POB) and d35 (Ocy) IDG-SW3 cells. See text for details. e Genes were categorized based on the presence of Ocy-specific Sp7 enhancer association in Ocy454 cells. Then, the effect of Sp7 shRNA (versus LacZ shRNA) was reported as the absolute value of the log2 fold change. Genes bound by Sp7 show, on average, a greater effect of Sp7 knockdown than genes without Sp7 enhancer binding sites. Two-tailed Welch’s t test was used, p < 0.0001. f De novo motif analysis of osteocyte-specific, osteoblast-specific, and shared distal Sp7 peaks. See also Supplementary Data 4 and 5. g 77 genes (Supplementary Data 6) are revealed by intersecting transcripts regulated by both Sp7 knockdown and overexpression in Ocy454 cells (FDR < 0.05, 146 genes) and genes with associated Ocy454 cell-specific Sp7 ChIP-seq peaks (6,648 genes).