Zebrafish DeltaNp63 is a direct target of Bmp signaling and encodes a transcriptional repressor blocking neural specification in the ventral ectoderm.Has2 is required upstream of Rac1 to govern dorsal migration of lateral cells during zebrafish gastrulation.Fgf signaling induces posterior neuroectoderm independently of Bmp signaling inhibition.Destabilization of DeltaNp63alpha by Nedd4-mediated ubiquitination and Ubc9-mediated sumoylation, and its implications on dorsoventral patterning of the zebrafish embryo.