The influence of ecological factors on cnidarian venoms

Abstract

Venom research is often focussed on medical relevance, novel compounds and venom evolution, whilst studying the relationship between a venom and its environment – venom ecology - has been conducted to a lesser extent. Given the projected environmental changes envisioned to occur with global warming, it is pertinent now more than ever, to highlight this topic. Here we review literature examining the influence of ecological factors such as environmental temperature, salinity, ontogeny, geographic location and diet on cnidarian venoms. This review provides an exclusive focus on the cnidarian phylum and encompasses all available published, peer-reviewed literature to our knowledge regarding the ecological factors influencing venom. We find a startling lack of research into the effects of both environmental and biological factors on venoms, with very few to no studies available per category. Importantly, research does exist that suggest these ecological processes may influence other marine or terrestrial venoms, thus we recommend future research is needed to explore this concept in cnidarians.

Venoms for all occasions: The functional toxin profiles of different anatomical regions in sea anemones are related to their ecological function

“…This arrangement allows for the regulation of venom composition at a single cell level, and indeed subpopulations of a single nematocyst type can be differentiated by their toxin expression profiles (Columbus‐Shenkar et al, 2018). Furthermore, ecological factors are known to drive changes in toxin gene expression (O'Hara et al, 2021), resulting in spatiotemporal differences in venom composition across morphological regions, life stages and cellular developmental stages (Macrander et al, 2016; Moran et al, 2013; Nicosia et al, 2013; Sachkova et al, 2019; Sunagar et al, 2018; Surm et al, 2019). In actiniarians, venom is utilized for prey capture, digestion and defence against predators among other functions, and the division of these functions across envenomating tissues is likely to be a major determinant of toxin expression patterns.…”

Implications of bleaching on cnidarian venom ecology

“…A range of ecological factors have been shown to impact on the venom profile and expenditure in cnidarians ( O'Hara et al, 2021 ). Briefly, venom variations and/or changes have been attributed to differences in temperature ( Jouiaei et al, 2015a ; O'Hara et al, 2018 ; Oakley et al, 2017 ; Richier et al, 2008 ; Sachkova et al, 2020 ; Sunagawa et al, 2009 ), age ( Columbus-Shenkar et al, 2018 ; Klompen et al, 2018 ; McClounan and Seymour, 2012 ; Underwood and Seymour, 2007 ), diet ( Underwood and Seymour, 2007 ), location ( Winter et al, 2010 ; Yue et al, 2019 ), salinity ( Sachkova et al, 2020 ), ultraviolet radiation ( Richier et al, 2008 ; Sachkova et al, 2020 ), interspecies competition ( Yosef et al, 2020 ) and predation pressure ( Ben-Ari et al, 2018 ).…”

Transcriptomic Insights into the Diversity and Evolution of Myxozoa (Cnidaria, Endocnidozoa) Toxin-like Proteins

“…However, relatively few studies have been conducted within the parasitic cnidarians—Endocnidozoa. Considering that ecological factors have a profound influence on intra-species venom variation [ 5 ], this bias will not only compromise our understanding of venom diversity but also limit the exploration of venom function [ 6 ].…”