Molecular Searching for Gill Slits in Echinoderms: Hox1 expression in Strongylocentrotus purpuratus

The formation of gill slits is a homologous trait in most deuterostomes (including hemichordates, tunicates, lancelets, and vertebrates), however is not present in the Phylum Echinodermata. Thus, there may be a difference in gene order or gene expression. The anterior Hox1 gene is responsible for gill slit formation (among other things), and is present in all deuterostomes, but perhaps in a different context. In this study, I performed phylogenetic analysis to determine how similar Hox1 was in echinoderms and hemichordates. My results show that they are divergent genes and therefore a laboratory experiment is possible. The next step would be to observe and compare Hox1 expression in both an echinoderm and a hemichordate