Transcription factor, which is involved in craniofacial development, in odontogenic region definition, and in stomach organogenesis. Binds to a regulatory module of the NCAM promoter. Expressed predominantly in the facial primordia, developing stomach, and proximal limbs. First detectable in the facial primordia at stage 18 after neural crest migration. Expressed in regions derived from both mid- and hindbrain neural crest. Also expressed in the developing cartilage elements of the limb, first within a restricted population in the prechondrogenic mesenchyme and later in the rounded chondrocytes at the epiphyses of developing long bones. Belongs to the BAR homeobox family.