Dorsalizing factor. Key developmental protein that dorsalizes early vertebrate embryonic tissues by binding to ventralizing TGF-beta family bone morphogenetic proteins (BMPs) and sequestering them in latent complexes (By similarity). Interacts with twsg1 and/or bmp4. During gastrulation, levels are highest in the organizer region. Also present in the developing brain and in paraxial mesoderm and ectoderm. First detected shortly after the midbastula transition. Levels increase during gastrulation, persist through early somatogenesis, but then decrease and are gone by 24 hours. Cleaved by tolloid proteases; cleavage participates in dorsoventral patterning during early development. Belongs to the chordin family.