Inhibits wnt, nodal/nr-1 and bmp signaling in the embryo to promote head formation and anterior neural induction. Within the endoderm, acts as an essential mediator of nodal/nr-1-induced cardiogenesis in the overlying mesoderm. The long chain interacts with nodal/nr-1, bmp4 and wnt8, thereby inhibiting their function. The short chain interacts with nodal/nr-1 but not bmp4 or wnt8. A component of the Nieuwkoop signaling center in the blastula. Expressed transiently in a broad anterior domain of the gastrula, including the anterior endoderm of the Spemann's organizer and more laterally the cardiac primordia. Expression is excluded from the prospective prechordal plate region and the ring of cells that give rise to the trunk-tail mesoderm. Expressed both maternally and zygotically. Zygotic expression increases at stage 10 (early gastrula), continues during gastrula and early neurula stages before rapidly declining during neurulation. By nodal/nr-1 signaling and wnt8 signaling including the downstream effectors mix-A/mix.1 and siamois acting synergistically with either lhx1/lim1 or otx2. Also by acvr1b/alk4. Microinjection of cer1 into blastomeres results in the formation of ectopic heads that contain cyclopic eyes as well as duplicated internal organs such as liver and heart. The heart beats at a rhythm different to that of the primary heart. Based on this phenotype the name 'cerberus' was chosen after a mythological guardian dog with multiple heads. Belongs to the DAN family.