Dorsalizing factor. Antagonizes mesoderm formation by nodal-like proteins and ventralizing BMPs. Cooperates with cer1 to promote embryonic head formation. Homodimer. Can form heterodimers with admp, bmp2-I and/or bmp2-II, derriere and nodal/nr-1. Tends to mark the dorsal ectodermal and mesodermal cells. Initially expressed in the dorsal-lateral ectoderm, and subsequently extends through the entire neural plate at the neurula stage. Also expressed in the prechordal plate. Prechordal plate mesoderm specifies anterior neuroectoderm and pharyngeal endoderm, which are progenitors for the formation of head structures. At the hatching stage, enriched from the dorsal mesenchyme to the olfactory pit and optic cup. The region required for head formation is located in the propeptide, which itself interferes with proteolytic processing of the precursor. The mature region has the same activity as that of BMP3. Belongs to the TGF-beta family.