Meeting Abstract
Certain annelid lineages use venom for predation or defensive purposes. Amphinomids (Amphinomida, Annelida), more commonly known as fireworms, constitute a group of marine polychaetes characterized by having defensive calcareous chaetae that break off upon contact and deliver an inflammatory substance, which can cause skin irritation and a painful burning sensation. However, a venom producing tissue has not been identified and knowledge on fireworm venom is scarce, with only one known active toxin, complanine, isolated from Eurythoe complanata. To date, neither complanine, nor any other potential toxic components of fireworm venom have been characterized on a molecular level. Here we use next-generation sequencing to analyze the transcriptomic profile of Hermodice carunculata body tissue and identify for the first time putative venom toxins in this species. A great diversity of transcripts coding for putative peptide toxins and venom-related proteins are expressed in H. carunculata transcriptome. These transcripts represent a variety of toxin classes that have been repeatedly recruited into animal venoms, including C-type lectins, Kazal domain protease inhibitors, Gigantoxin-like neurotoxins and Ryncolin-like peptides. Interestingly, several identified transcripts have specific domains homologous to the snake three-finger toxin (3FTx) and appear to be unique to H. carunculata. While proteomic and functional studies are needed to confirm the putative H. carunculata toxins identified, our results suggest that venom has also convergently evolved in fireworms, which use effective and complex venoms to deter predators.
