Transcriptional activator (By similarity). May be involved in the dorso-ventral patterning of the mesoderm. After the mid-blastula transition, expressed in the dorsolateral mesoderm but not within the dorsal blastopore lip. During gastrulation and neurulation, expressed within the dorsal mesoderm and the lateral border of the neural plate but not within the dorsal midline. In neurula stage embryos, expressed throughout the entire somite-forming mesoderm, at the border between mesoderm and ectoderm but not within the notochord, neuroectoderm or lateral plate mesoderm. From stage 25 to stage 32, expressed in branchial arches, head mesenchyme, neural crest cells, tail tip and in two segmented lines of cells bordering the somites. Tail tip expression persists throughout later development. From stage 32, expressed in the ventral abdominal muscle and around the spinal cord. Only weakly expressed in the pronephric tubules. At hatching, expressed within the heart, foregut, hindbrain and pharyngeal pouches. Expression begins after the mid-blastula transition (stage 8-8.5) becoming most abundant during gastrulation, then decreasing as development progresses. Expression remains at a very low level during the tailbud and tadpole stages.