A sea urchin gene encodes a polypeptide homologous to epidermal growth factor

A sea urchin DNA clone complementary to an embryonic messenger RNA whose protein product bears striking homology to the epidermal growth factor family of proteins has been identified and characterized. The structure of the protein is similar to that of previously identified regulatory genes in Drosophila and Caenorhabditis. RNA gel blot hybridization showed a unique temporal pattern of expression of this gene during embryogenesis and transcript enrichment in the embryonic ectoderm. These results suggest that this member of the epidermal growth factor gene family plays a role in early development decisions in sea urchin embryos.