Figure 2.

(A) Functionally important residues identified on EqII [43]. Functional sites are as follows: (B) site of bend when N-terminus comes into contact with the cell membrane, (POC) residues involved with the POC binding site, (O) residues involved with oligomerization, (S) key sphingomyelin binding site. Colors are used to aid in determining the orientation between the two views shown; (B) Characterization of amino acid variation for the different gene clusters (Clade 1, Clade 2M, Clade 2A) identified in our analysis. SeqLogo graphs for residues that have been identified previously as functionally important above the alignment with the size of each amino acid residue representing the frequency in which these residues occurred in the alignment. Numbers along the bottom correspond to positions of specific amino acid residues in EqII; (C) Maximum Likelihood actinoporin gene tree produced in FastTree2. Colored branches depict superfamily associations (see Figure 1, Yellow: Actinostoloidea, Red: Actinioidea, Green: Metridioidea). Bootstrapping values greater than 50 are shown at the nodes. Branch labels include GenBank ID (when applicable) and the species from which the toxin gene was derived. Bold labels indicate that the mature protein sequence was recovered. Sequences derived from genomic data are indicated with “G” following species in sequence IDs. The superfamily association for Actineria villosa may be incorrect and is noted with an asterisk.