Ancestral network module regulating prdm1 expression in the lamprey neural plate border.

prdm1 is an important transcriptional regulator that plays diverse roles during development of a wide variety of vertebrate and invertebrate species. prdm1 is required for neural crest specification in zebrafish, but not in mouse embryos. The role of this gene in neural crest formation in other species has not been examined, and its regulation during embryonic development is poorly understood. Here, we investigate the expression pattern, function, and the upstream regulatory inputs into prdm1 during lamprey neural crest development. prdm1 is strongly expressed in the lamprey neural plate border, suggesting a conserved ancestral role of this gene in the neural crest formation. We found that lamprey neural plate border expression of prdm1 is activated by Ap-2 and Msx, but is independent of Pax3/7 and Zic.