Transcriptional factor involved in bone development. Acts as an immediate early BMP-responsive transcriptional activator essential for osteoblast differentiation. Stimulates ALPL promoter activity in a RUNX2-independent manner during osteoblast differentiation. Stimulates SP7 promoter activity during osteoblast differentiation. Promotes cell proliferation by up-regulating MYC promoter activity. Involved as a positive regulator of both chondrogenesis and chondrocyte hypertrophy in the endochondral skeleton. Binds to the homeodomain-response element of the ALPL and SP7 promoter. Binds to the MYC promoter. Requires the 5'-TAATTA-3' consensus sequence for DNA-binding (By similarity). Interacts with XRCC6 (Ku70). Mainly expressed in several neuronal tissues and developing tissues. Present at high levels in embryos on embryonic day 14 (E14), in skeletal tissues on E18, and in adult brain. At lower levels in newborn rib cartilage, embryo soft tissues on E18, newborn skin and adult heart. Phosphorylated. Phosphorylation of Ser-34 and Ser-217 by MAPK14 enhances its transcriptional activity. Phosphorylation by CaMK2 increases its protein stability (By similarity). Belongs to the distal-less homeobox family.