Seems to antagonize the function of BMP4 by binding to it and preventing its interaction with receptors. Alters the fate commitment of neural stem cells from gliogenesis to neurogenesis. Contributes to neuronal differentiation of neural stem cells in the brain by preventing the adoption of a glial fate. May play a crucial role in dorsoventral axis formation (By similarity). Antagonizes the function of BMP7 and may thus play an important role in the embryonic bone formation. Shows no inhibitory effect on the inducing activity of BMP2. Plays a role during anterior segment eye development (By similarity). Expressed in heart, brain, lung, liver, kidney and testis. Expression starts in the neural plate at mid-gastrulation. Later on its expression becomes restricted to discrete regions of the central nervous system and to derivatives of the neural crest cells. Expressed as well in the primordial cells of the skeleton in mice embryos at 13.5 dpc. May be glycosylated.