Transcription factor involved in osteoblastic differentiation and skeletal morphogenesis. Essential for the maturation of osteoblasts and both intramembranous and endochondral ossification. CBF binds to the core site, 5'-PYGPYGGT-3', of a number of enhancers and promoters, including murine leukemia virus, polyomavirus enhancer, T-cell receptor enhancers, osteocalcin, osteopontin, bone sialoprotein, alpha 1(I) collagen, LCK, IL-3 and GM-CSF promoters. Inhibits KAT6B-dependent transcriptional activation. In osteoblasts, supports transcription activation: synergizes with SPEN/MINT to enhance FGFR2-mediated activation of the osteocalcin FGF-responsive element (OCFRE). Heterodimer of an alpha and a beta subunit. The alpha subunit binds DNA as a monomer and through the Runt domain. DNA-binding is increased by heterodimerization (By similarity). Interacts with XRCC6 (Ku70) and XRCC5 (Ku80). Interacts with CCNB1, KAT6A and KAT6B. Interacts with HIVEP3. Interacts with IFI204. Interaction with SATB2; the interaction results in enhanced DNA binding and transactivation by these transcription factors. Binds to HIPK3. Interacts (isoform 3) with DDX5. Interacts with FOXO1 (via a C-terminal region); the interaction inhibits RUNX2 transcriptional activity towards BGLAP. Interacts with FOXP3. Interacts with TMEM119. Interacts with OLFM2 (PubMed:28062493). Phosphorylated; probably by MAP kinases (MAPK). Phosphorylation by HIPK3 is required for the SPEN/MINT and FGF2 transactivation during osteoblastic differentiation (By similarity).