Figure 3.

Phylogenic tree analysis of all the identified X₁PRX₂amide preprohormones from scyphozoans, staurozoans, cubozoans, and octocorallians. This phylogenetic tree (left panel) is in complete accordance with the phylogenetic tree given in Figure 1. The abscissa (upper line) gives the length of the preprohormone fragments (in amino acid residues). The middle panel gives schematic representations of the various preprohormones from each species. The right panel gives the amino acid sequences of the major X₁PRX₂amide peptides produced by these preprohormones. This panel also shows that X₁PRX₂amide (where X₂ is either S, A, or G) is the consensus sequence of all peptides.