Meeting Abstract

31.8  Sunday, Jan. 5 09:45  The evolution of the sodium and potassium ion channel toxins in sea anemones: a combined RNASeq and bioinformatics approach. MACRANDER, J*; DALY, M; Ohio State University; Ohio State University macrander.1@osu.edu

Sea anemones (Cnidaria, Anthozoa, Actiniaria) use toxins in prey acquisition, predator avoidance and conspecific interactions. Although about 250 compounds have been identified from the venom cocktails of anemone species, relatively few toxin genes are known and their phylogenetic history is poorly understood. Of these genes, the voltage-gated Na+ (Nav) and K+ (Kv) channel toxins are the best characterized; however, the majority of these are characterized from members of family Actiniidae. To better understand toxin gene evolution throughout Actiniaria, we used RNASeq in combination with transcriptomes and genomes from Genbank to identify new candidate toxin genes for species previously investigated (Anthopleura elegantissima, Aiptasia pallida, Metridium senile, and others) and for species for which there are no known toxin genes (Isosicyonis sp, Hormothia digitata, Bolocera tuediae and others). Our phylogenetic analysis of the Nav genes revealed a pattern of gene family evolution contrasting the concerted evolution model previously proposed. Several Nav and Kv candidate genes are multi-copy, and sometimes these falling outside the same lineage as similar types previously described; whether these are pseudogenes or differential selection acting on toxin genes is yet to be determined. Additional sampling throughout Actiniaria is necessary provide an accurate understanding how these gene families evolve across sea anemones as a whole.