Never, Ever Make an Enemy… Out of an Anemone: Transcriptomic Comparison of Clownfish Hosting Sea Anemone Venoms

Abstract

Sea anemones are predatory marine invertebrates and have diverse venom arsenals. Venom is integral to their biology, and is used in competition, defense, and feeding. Three lineages of sea anemones are known to have independently evolved symbiotic relationships with clownfish, however the evolutionary impact of this relationship on the venom composition of the host is still unknown. Here, we investigate the potential of this symbiotic relationship to shape the venom profiles of the sea anemones that host clownfish. We use transcriptomic data to identify differences and similarities in venom profiles of six sea anemone species, representing the three known clades of clownfish-hosting sea anemones. We recovered 1121 transcripts matching verified toxins across all species, and show that hemolytic and hemorrhagic toxins are consistently the most dominant and diverse toxins across all species examined. These results are consistent with the known biology of sea anemones, provide foundational data on venom diversity of these species, and allow for a review of existing hierarchical structures in venomic studies.

Structure–function relationships in ShKT domain peptides: ShKT‐Ts1 from the sea anemone Telmatactis stephensoni

“…Numerous genomic, transcriptomic, and proteomic studies of sea anemones have been reported recently 7,31–35 . These studies further highlight, among other findings, the abundance of ShKT domains in sea anemones, and thus the importance of characterizing their function(s).…”

“…Numerous genomic, transcriptomic, and proteomic studies of sea anemones have been reported recently. 7,[31][32][33][34][35] These studies further highlight, among other findings, the abundance of ShKT domains in sea anemones, and thus the importance of characterizing their function(s). One potential indicator of activity against voltage-gated potassium channels is the presence of a KY (Lys-Tyr) dyad in the sequence, where the Lys and Tyr side chains are in close spatial proximity, as first noted by Ménez et al 25 Subsequently, it has been recognized that the function of the Tyr residue can be served by a Phe or even a long aliphatic side chain.…”

Marine natural products

“…558 Analysis of the transcriptomes from six species of clownfish hosting anemones, including Cryptodendrum adhaesivum , Stichodactyla haddoni , Heterodactyla hemprichii , Heteractis crispa , Macrodactyla doreensis and Entacmaea quadricolor identified a large number of toxins with reported hemolytic and hemorrhagic properties. 559…”

Diversity analysis of sea anemone peptide toxins in different tissues of Heteractis crispa based on transcriptomics

“…published an article in which they mentioned that Radianthus macrodactylus is equivalent to Heteractis crispa 26 . Some toxins have been detected in H. crispa , mainly actinoporin, Kunitz-type protease inhibitors, Nav channel toxins, and Kv channel toxins 26 – 29 , and the venom assembly in the tentacles, mesentery filaments, and columns of three species of sea anemones ( Anemonia sulcata , H. crispa , and Megalactis griffithsi ) has been investigated, and the number of toxin-like genes varies significantly between tissues and species 22 , 30 , 31 . The high-throughput sequencing (HTS) technology has been increasingly applied in studying sea anemone venom components, such as Stichodactyla haddoni and Anthopleura dowii 32 – 34 .…”