Venom System Research Articles

Lacewing venom: Detailed insights into the venom system of a neglected group of venomous insects

Lacewing venom: Detailed insights into the venom system of a neglected group of venomous insects

A roadmap to the enzymes from spider venom: biochemical ecology, molecular diversity, and value for the bioeconomy

Spiders are ancient and highly successful predators, which use venom for both predation and defense. Their venoms are complex mixtures of potent biological molecules, emerging as a prolific source of biomolecular innovation in agriculture, biomedicine, and bioeconomy. While small cysteine-rich neurotoxins are typically considered the main components of spider venoms, recent research has shown that spider venoms also contain many high-molecular-weight proteins, especially enzymes. To date, very little is known about the diversity, biochemistry and ecology of these components. Here, we provide the first systematic overview of spider venom enzymes, describing all known examples in terms of their properties and functions in the spider venom system. We argue that the sheer diversity of these neglected spider venom compounds offers significant translational potential and holds great potential for the bioeconomy, reflecting a wide range of technical applications such as industrial production, food processing, and waste management.

Divergent venom effectors correlate with ecological niche in neuropteran predators

Neuropteran larvae are fierce predators that use venom to attack and feed on arthropod prey. Neuropterans have adapted to diverse and sometimes extreme habitats, suggesting their venom may have evolved accordingly, but the ecology and evolution of venom deployment in different families is poorly understood. We applied spatial transcriptomics, proteomics, morphological analysis, and bioassays to investigate the venom systems in the antlion Euroleon nostras and the lacewing Chrysoperla carnea, which occupy distinct niches. Although the venom system morphology was similar in both species, we observed remarkable differences at the molecular level. E. nostras produces particularly complex venom secreted from three different glands, indicating functional compartmentalization. Furthermore, E. nostras venom and digestive tissues were devoid of bacteria, strongly suggesting that all venom proteins are of insect origin rather than the products of bacterial symbionts. We identified several toxins exclusive to E. nostras venom, including phospholipase A2 and several undescribed proteins with no homologs in the C. carnea genome. The compositional differences have significant ecological implications because only antlion venom conferred insecticidal activity, indicating its use for the immobilization of large prey. Our results indicate that molecular venom evolution plays a role in the adaptation of antlions to their unique ecological niche.

Mandibular gland proteomics of the Mexican alligator lizard, Abronia graminea, and the red-lipped arboreal alligator lizard, Abronia lythrochila

A useful approach to deepen our knowledge about the origin and evolution of venom systems in Reptilia has been exploring the vast biodiversity of this clade of vertebrates in search of orally produced proteins with toxic actions, as well as their corresponding delivery systems. The occurrence of toxins in anguimorph lizards has been demonstrated experimentally or inferred from reports of the toxic effects of the oral secretions of taxa within the Varanidae and Helodermatidae families. In the present study, we have focused on two alligator lizards of the Anguidae family, the Mexican alligator lizard, Abronia graminea, and the red-lipped arboreal alligator lizard, A. lythrochila. In addition, the fine morphology of teeth of the latter species is described. The presence of a conserved set of proteins, including B-type natriuretic peptides, cysteine-rich secretory proteins, group III phospholipase A2, and kallikrein, in submandibular gland extracts was demonstrated for both Abronia species. These proteins belong to toxin families found in oral gland secretions of venomous reptile species. This finding, along with previous demonstration of toxin-producing taxa in both paleo- and neoanguimorpha clades, provides further support for the existence of a handful of conserved toxin families in oral secretions across the 100+ million years of Anguimorpha cladogenesis.

Diversely evolved xibalbin variants from remipede venom inhibit potassium channels and activate PKA-II and Erk1/2 signaling

BackgroundThe identification of novel toxins from overlooked and taxonomically exceptional species bears potential for various pharmacological applications. The remipede Xibalbanus tulumensis, an underwater cave-dwelling crustacean, is the only crustacean for which a venom system has been described. Its venom contains several xibalbin peptides that have an inhibitor cysteine knot (ICK) scaffold.ResultsOur screenings revealed that all tested xibalbin variants particularly inhibit potassium channels. Xib1 and xib13 with their eight-cysteine domain similar to spider knottins also inhibit voltage-gated sodium channels. No activity was noted on calcium channels. Expanding the functional testing, we demonstrate that xib1 and xib13 increase PKA-II and Erk1/2 sensitization signaling in nociceptive neurons, which may initiate pain sensitization. Our phylogenetic analysis suggests that xib13 either originates from the common ancestor of pancrustaceans or earlier while xib1 is more restricted to remipedes. The ten-cysteine scaffolded xib2 emerged from xib1, a result that is supported by our phylogenetic and machine learning-based analyses.ConclusionsOur functional characterization of synthesized variants of xib1, xib2, and xib13 elucidates their potential as inhibitors of potassium channels in mammalian systems. The specific interaction of xib2 with Kv1.6 channels, which are relevant to treating variants of epilepsy, shows potential for further studies. At higher concentrations, xib1 and xib13 activate the kinases PKA-II and ERK1/2 in mammalian sensory neurons, suggesting pain sensitization and potential applications related to pain research and therapy. While tested insect channels suggest that all probably act as neurotoxins, the biological function of xib1, xib2, and xib13 requires further elucidation. A novel finding on their evolutionary origin is the apparent emergence of X. tulumensis-specific xib2 from xib1. Our study is an important cornerstone for future studies to untangle the origin and function of these enigmatic proteins as important components of remipede but also other pancrustacean and arthropod venoms.

Proteins from shrews’ venom glands play a role in gland functioning and venom production

Venom production has evolved independently many times in the animal kingdom, although it is rare among mammals. Venomous shrews produce venom in their submandibular salivary glands and use it for food acquisition. Only a few toxins have been identified in shrew venoms thus far, and their modes of action require investigation. The biological and molecular processes relating to venom production and gland functioning also remain unknown. To address this gap, we investigated protein content in extracts from venom glands of two shrew species, Neomys fodiens and Sorex araneus, and interpreted their biological functions. Applying a proteomic approach coupled with Gene Ontology enrichment analysis, we identified 313 and 187 putative proteins in venom glands of N. fodiens and S. araneus, respectively. A search of the UniProt database revealed that most of the proteins found in both shrew species were involved in metabolic processes and stress response, while GO enrichment analysis revealed more stress-related proteins in the glands of S. araneus. Molecules that regulate molecule synthesis, cell cycles, and cell divisions are necessary to enable venom regeneration and ensure its effectiveness in predation and food hoarding. The presence of proteins involved in stress response may be the result of shrews’ high metabolic rate and the costs of venom replenishment. Some proteins are likely to promote toxin spreading during envenomation and, due to their proteolytic action, reinforce venom toxicity. Finally, finding numerous proteins involved in immune response suggests a potential role of shrew venom gland secretions in protection against pathogens. These findings open up new perspectives for studying biological functions of molecules from shrew venom glands and extend our knowledge on the functioning of eulipotyphlan venom systems. Because the majority of existing and putative venomous mammals use oral venom systems to inject venom into target species, the methods presented here provide a promising avenue for confirming or discovering new taxa of venomous mammals.

Venom gland organogenesis in the common house spider

Venom is a remarkable innovation found across the animal kingdom, yet the evolutionary origins of venom systems in various groups, including spiders, remain enigmatic. Here, we investigated the organogenesis of the venom apparatus in the common house spider, Parasteatoda tepidariorum. The venom apparatus consists of a pair of secretory glands, each connected to an opening at the fang tip by a duct that runs through the chelicerae. We performed bulk RNA-seq to identify venom gland-specific markers and assayed their expression using RNA in situ hybridisation experiments on whole-mount time-series. These revealed that the gland primordium emerges during embryonic stage 13 at the chelicera tip, progresses proximally by the end of embryonic development and extends into the prosoma post-eclosion. The initiation of expression of an important toxin component in late postembryos marks the activation of venom-secreting cells. Our selected markers also exhibited distinct expression patterns in adult venom glands: sage and the toxin marker were expressed in the secretory epithelium, forkhead and sum-1 in the surrounding muscle layer, while Distal-less was predominantly expressed at the gland extremities. Our study provides the first comprehensive analysis of venom gland morphogenesis in spiders, offering key insights into their evolution and development.

Prey Shifts Drive Venom Evolution in Cone Snails.

Venom systems are complex traits that have independently emerged multiple times in diverse plant and animal phyla. Within each venomous lineage there typically exists interspecific variation in venom composition where several factors have been proposed as drivers of variation, including phylogeny and diet. Understanding these factors is of broad biological interest and has implications for the development of antivenom therapies and venom-based drug discovery. Because of their high species richness and the presence of several major evolutionary prey shifts, venomous marine cone snails (genus Conus) provide an ideal system to investigate drivers of interspecific venom variation. Here, by analyzing the venom gland expression profiles of ∼3,000 toxin genes from 42 species of cone snail, we elucidate the role of prey-specific selection pressures in shaping venom variation. By analyzing overall venom composition and individual toxin structures, we demonstrate that the shifts from vermivory to piscivory in Conus are complemented by distinct changes in venom composition independent of phylogeny. In vivo injections of venom from piscivorous cone snails in fish further showed a higher potency compared with venom of nonpiscivores demonstrating a selective advantage. Together, our findings provide compelling evidence for the role of prey shifts in directing the venom composition of cone snails and expand our understanding of the mechanisms of venom variation and diversification.

The venom and telopodal defence systems of the centipede Lithobius forficatus are functionally convergent serial homologues

BackgroundEvolution of novelty is a central theme in evolutionary biology, yet studying the origins of traits with an apparently discontinuous origin remains a major challenge. Venom systems are a well-suited model for the study of this phenomenon because they capture several aspects of novelty across multiple levels of biological complexity. However, while there is some knowledge on the evolution of individual toxins, not much is known about the evolution of venom systems as a whole. One way of shedding light on the evolution of new traits is to investigate less specialised serial homologues, i.e. repeated traits in an organism that share a developmental origin. This approach can be particularly informative in animals with repetitive body segments, such as centipedes.ResultsHere, we investigate morphological and biochemical aspects of the defensive telopodal glandular organs borne on the posterior legs of venomous stone centipedes (Lithobiomorpha), using a multimethod approach, including behavioural observations, comparative morphology, proteomics, comparative transcriptomics and molecular phylogenetics. We show that the anterior venom system and posterior telopodal defence system are functionally convergent serial homologues, where one (telopodal defence) represents a model for the putative early evolutionary state of the other (venom). Venom glands and telopodal glandular organs appear to have evolved from the same type of epidermal gland (four-cell recto-canal type) and while the telopodal defensive secretion shares a great degree of compositional overlap with centipede venoms in general, these similarities arose predominantly through convergent recruitment of distantly related toxin-like components. Both systems are composed of elements predisposed to functional innovation across levels of biological complexity that range from proteins to glands, demonstrating clear parallels between molecular and morphological traits in the properties that facilitate the evolution of novelty.ConclusionsThe evolution of the lithobiomorph telopodal defence system provides indirect empirical support for the plausibility of the hypothesised evolutionary origin of the centipede venom system, which occurred through functional innovation and gradual specialisation of existing epidermal glands. Our results thus exemplify how continuous transformation and functional innovation can drive the apparent discontinuous emergence of novelties on higher levels of biological complexity.

A Comparative Analysis of the Venom System between Two Morphotypes of the Sea Anemone Actinia equina.

The current study investigates the venom-delivery system of green and red morphotypes of the sea anemone Actinia equina to disclose its potential as a source of bioactive compounds. We compared the two morphotypes using electron and optical microscopy, proteomics, and toxicity assessment on zebrafish embryos. Specialized venom-injecting cells (nematocysts) are equally distributed and found in the tentacles of both varieties. Proteomics revealed proteins of interest in both red and green Actinia, yielding the three most abundant Gene Ontology (GO) terms related to the biological processes "proteolysis", "hemolysis in another organism" and "lipid catabolic process". Neurotoxins and cytolytic toxins similar to known cnidarian toxins like PsTX-60A and AvTX-60A, for instance, were identified in both types. Extracts from green and red anemones were toxic to zebrafish embryos, with green anemone venom appearing to be more potent. The findings highlight the presence of proteinaceous toxins in A. equina and the potential for different varieties to possess distinct bioactive compounds. Notably, pore-forming toxins are suggested for molecular probes and immunotoxins, making them valuable assets for potential biotechnological and biomedical purposes.

Towards the Exploration and Evolution of Insulin-like Venoms in Actiniaria (Sea anemones).

Recent studies have elucidated the diversity of genes encoding venom in Sea anemones. However, most of those genes are yet to be explored in an evolutionary context. Insulin is a common peptide across metazoans and has been coopted into a predatory venom in many venomous lineages. In this study, we focus on the diversity of insulin-derived venoms in Sea anemones and on elucidating their evolutionary history. We sourced data for 34 species of Sea anemones and found sequences belonging to two venom families which have Insulin PFAM annotations. Our findings show that both families have undergone duplication events. Members of each of the independently evolving clades have consistent predicted protein structures and distinct dN/dS values. Our work also shows that sequences allied with VP302 are part of a multidomain venom contig and have experienced a secondary gain into the venom system of cuticulate Sea anemones.

A Russian Doll of Resistance: Nested Gains and Losses of Venom Immunity in Varanid Lizards.

The interplay between predator and prey has catalyzed the evolution of venom systems, with predators honing their venoms in response to the evolving resistance of prey. A previous study showed that the African varanid species Varanus exanthematicus has heightened resistance to snake venoms compared to the Australian species V. giganteus, V. komodoensis, and V. mertensi, likely due to increased predation by sympatric venomous snakes on V. exanthematicus. To understand venom resistance among varanid lizards, we analyzed the receptor site targeted by venoms in 27 varanid lizards, including 25 Australian varanids. The results indicate an active evolutionary arms race between Australian varanid lizards and sympatric neurotoxic elapid snakes. Large species preying on venomous snakes exhibit inherited neurotoxin resistance, a trait potentially linked to their predatory habits. Consistent with the 'use it or lose it' aspect of venom resistance, this trait was secondarily reduced in two lineages that had convergently evolved gigantism (V. giganteus and the V. komodoensis/V. varius clade), suggestive of increased predatory success accompanying extreme size and also increased mechanical protection against envenomation due to larger scale osteoderms. Resistance was completely lost in the mangrove monitor V. indicus, consistent with venomous snakes not being common in their arboreal and aquatic niche. Conversely, dwarf varanids demonstrate a secondary loss at the base of the clade, with resistance subsequently re-evolving in the burrowing V. acanthurus/V. storri clade, suggesting an ongoing battle with neurotoxic predators. Intriguingly, within the V. acanthurus/V. storri clade, resistance was lost again in V. kingorum, which is morphologically and ecologically distinct from other members of this clade. Resistance was also re-evolved in V. glebopalma which is terrestrial in contrast to the arboreal/cliff dwelling niches occupied by the other members of its clade (V. glebopalma, V. mitchelli, V. scalaris, V. tristis). This 'Russian doll' pattern of venom resistance underscores the dynamic interaction between dwarf varanids and Australian neurotoxic elapid snakes. Our research, which included testing Acanthophis (death adder) venoms against varanid receptors as models for alpha-neurotoxic interactions, uncovered a fascinating instance of the Red Queen Hypothesis: some death adders have developed more potent toxins specifically targeting resistant varanids, a clear sign of the relentless predator-prey arms race. These results offer new insight into the complex dynamics of venom resistance and highlight the intricate ecological interactions that shape the natural world.

Comprehensive isoform-level analysis reveals the contribution of alternative isoforms to venom evolution and repertoire diversity.

Animal venom systems have emerged as valuable models for investigating how novel polygenic phenotypes may arise from gene evolution by varying molecular mechanisms. However, a significant portion of venom genes produce alternative mRNA isoforms that have not been extensively characterized, hindering a comprehensive understanding of venom biology. In this study, we present a full-length isoform-level profiling workflow integrating multiple RNA sequencing technologies, allowing us to reconstruct a high-resolution transcriptome landscape of venom genes in the parasitoid wasp Pteromalus puparum Our findings demonstrate that more than half of the venom genes generate multiple isoforms within the venom gland. Through mass spectrometry analysis, we confirm that alternative splicing contributes to the diversity of venom proteins, acting as a mechanism for expanding the venom repertoire. Notably, we identified seven venom genes that exhibit distinct isoform usages between the venom gland and other tissues. Furthermore, evolutionary analyses of venom serpin3 and orcokinin further reveal that the co-option of an ancient isoform and a newly evolved isoform, respectively, contributes to venom recruitment, providing valuable insights into the genetic mechanisms driving venom evolution in parasitoid wasps. Overall, our study presents a comprehensive investigation of venom genes at the isoform level, significantly advancing our understanding of alternative isoforms in venom diversity and evolution and setting the stage for further in-depth research on venoms.

Slowly Making Sense: A Review of the Two-Step Venom System within Slow (Nycticebus spp.) and Pygmy Lorises (Xanthonycticebus spp.).

Since the early 2000s, studies of the evolution of venom within animals have rapidly expanded, offering new revelations on the origins and development of venom within various species. The venomous mammals represent excellent opportunities to study venom evolution due to the varying functional usages, the unusual distribution of venom across unrelated mammals and the diverse variety of delivery systems. A group of mammals that excellently represents a combination of these traits are the slow (Nycticebus spp.) and pygmy lorises (Xanthonycticebus spp.) of south-east Asia, which possess the only confirmed two-step venom system. These taxa also present one of the most intriguing mixes of toxic symptoms (cytotoxicity and immunotoxicity) and functional usages (intraspecific competition and ectoparasitic defence) seen in extant animals. We still lack many pieces of the puzzle in understanding how this venom system works, why it evolved what is involved in the venom system and what triggers the toxic components to work. Here, we review available data building upon a decade of research on this topic, focusing especially on why and how this venom system may have evolved. We discuss that research now suggests that venom in slow lorises has a sophisticated set of multiple uses in both intraspecific competition and the potential to disrupt the immune system of targets; we suggest that an exudate diet reveals several toxic plants consumed by slow and pygmy lorises that could be sequestered into their venom and which may help heal venomous bite wounds; we provide the most up-to-date visual model of the brachial gland exudate secretion protein (BGEsp); and we discuss research on a complement component 1r (C1R) protein in saliva that may solve the mystery of what activates the toxicity of slow and pygmy loris venom. We conclude that the slow and pygmy lorises possess amongst the most complex venom system in extant animals, and while we have still a lot more to understand about their venom system, we are close to a breakthrough, particularly with current technological advances.

Horizontal gene transfer underlies the painful stings of asp caterpillars (Lepidoptera: Megalopygidae)

Larvae of the genus Megalopyge (Lepidoptera: Zygaenoidea: Megalopygidae), known as asp or puss caterpillars, produce defensive venoms that cause severe pain. Here, we present the anatomy, chemistry, and mode of action of the venom systems of caterpillars of two megalopygid species, the Southern flannel moth Megalopyge opercularis and the black-waved flannel moth Megalopyge crispata. We show that megalopygid venom is produced in secretory cells that lie beneath the cuticle and are connected to the venom spines by canals. Megalopygid venoms consist of large aerolysin-like pore-forming toxins, which we have named megalysins, and a small number of peptides. The venom system differs markedly from those of previously studied venomous zygaenoids of the family Limacodidae, suggestive of an independent origin. Megalopygid venom potently activates mammalian sensory neurons via membrane permeabilization and induces sustained spontaneous pain behavior and paw swelling in mice. These bioactivities are ablated by treatment with heat, organic solvents, or proteases, indicating that they are mediated by larger proteins such as the megalysins. We show that the megalysins were recruited as venom toxins in the Megalopygidae following horizontal transfer of genes from bacteria to the ancestors of ditrysian Lepidoptera. Megalopygids have recruited aerolysin-like proteins as venom toxins convergently with centipedes, cnidarians, and fish. This study highlights the role of horizontal gene transfer in venom evolution.

The State of Squamate Genomics: Past, Present, and Future of Genome Research in the Most Speciose Terrestrial Vertebrate Order.

Squamates include more than 11,000 extant species of lizards, snakes, and amphisbaenians, and display a dazzling diversity of phenotypes across their over 200-million-year evolutionary history on Earth. Here, we introduce and define squamates (Order Squamata) and review the history and promise of genomic investigations into the patterns and processes governing squamate evolution, given recent technological advances in DNA sequencing, genome assembly, and evolutionary analysis. We survey the most recently available whole genome assemblies for squamates, including the taxonomic distribution of available squamate genomes, and assess their quality metrics and usefulness for research. We then focus on disagreements in squamate phylogenetic inference, how methods of high-throughput phylogenomics affect these inferences, and demonstrate the promise of whole genomes to settle or sustain persistent phylogenetic arguments for squamates. We review the role transposable elements play in vertebrate evolution, methods of transposable element annotation and analysis, and further demonstrate that through the understanding of the diversity, abundance, and activity of transposable elements in squamate genomes, squamates can be an ideal model for the evolution of genome size and structure in vertebrates. We discuss how squamate genomes can contribute to other areas of biological research such as venom systems, studies of phenotypic evolution, and sex determination. Because they represent more than 30% of the living species of amniote, squamates deserve a genome consortium on par with recent efforts for other amniotes (i.e., mammals and birds) that aim to sequence most of the extant families in a clade.

Venom biotechnology: casting light on nature's deadliest weapons using synthetic biology.

Venoms are complex chemical arsenals that have evolved independently many times in the animal kingdom. Venoms have attracted the interest of researchers because they are an important innovation that has contributed greatly to the evolutionary success of many animals, and their medical relevance offers significant potential for drug discovery. During the last decade, venom research has been revolutionized by the application of systems biology, giving rise to a novel field known as venomics. More recently, biotechnology has also made an increasing impact in this field. Its methods provide the means to disentangle and study venom systems across all levels of biological organization and, given their tremendous impact on the life sciences, these pivotal tools greatly facilitate the coherent understanding of venom system organization, development, biochemistry, and therapeutic activity. Even so, we lack a comprehensive overview of major advances achieved by applying biotechnology to venom systems. This review therefore considers the methods, insights, and potential future developments of biotechnological applications in the field of venom research. We follow the levels of biological organization and structure, starting with the methods used to study the genomic blueprint and genetic machinery of venoms, followed gene products and their functional phenotypes. We argue that biotechnology can answer some of the most urgent questions in venom research, particularly when multiple approaches are combined together, and with other venomics technologies.

Genomic and transcriptomic analyses support a silk gland origin of spider venom glands

BackgroundSpiders comprise a hyperdiverse lineage of predators with venom systems, yet the origin of functionally novel spider venom glands remains unclear. Previous studies have hypothesized that spider venom glands originated from salivary glands or evolved from silk-producing glands present in early chelicerates. However, there is insufficient molecular evidence to indicate similarity among them. Here, we provide comparative analyses of genome and transcriptome data from various lineages of spiders and other arthropods to advance our understanding of spider venom gland evolution.ResultsWe generated a chromosome-level genome assembly of a model spider species, the common house spider (Parasteatoda tepidariorum). Module preservation, GO semantic similarity, and differentially upregulated gene similarity analyses demonstrated a lower similarity in gene expressions between the venom glands and salivary glands compared to the silk glands, which questions the validity of the salivary gland origin hypothesis but unexpectedly prefers to support the ancestral silk gland origin hypothesis. The conserved core network in the venom and silk glands was mainly correlated with transcription regulation, protein modification, transport, and signal transduction pathways. At the genetic level, we found that many genes in the venom gland-specific transcription modules show positive selection and upregulated expressions, suggesting that genetic variation plays an important role in the evolution of venom glands.ConclusionsThis research implies the unique origin and evolutionary path of spider venom glands and provides a basis for understanding the diverse molecular characteristics of venom systems.

Localization of Multiple Jellyfish Toxins Shows Specificity for Functionally Distinct Polyps and Nematocyst Types in a Colonial Hydrozoan.

Hydractinia symbiolongicarpus is a colonial hydrozoan that displays a division of labor through morphologically distinct and functionally specialized polyp types. As with all cnidarians, their venoms are housed in nematocysts, which are scattered across an individual. Here, we investigate the spatial distribution of a specific protein family, jellyfish toxins, in which multiple paralogs are differentially expressed across the functionally specialized polyps. Jellyfish toxins (JFTs) are known pore-forming toxins in the venoms of medically relevant species such as box jellyfish (class Cubozoa), but their role in other medusozoan venoms is less clear. Utilizing a publicly available single-cell dataset, we confirmed that four distinct H. symbiolongicarpus JFT paralogs are expressed in nematocyst-associated clusters, supporting these as true venom components in H. symbiolongicarpus. In situ hybridization and immunohistochemistry were used to localize the expression of these JFTs across the colony. These expression patterns, in conjunction with known nematocyst type distributions, suggest that two of these JFTs, HsymJFT1c-I and HsymJFT1c-II, are localized to specific types of nematocysts. We further interpret JFT expression patterns in the context of known regions of nematogenesis and differential rates of nematocyst turnover. Overall, we show that JFT expression patterns in H. symbiolongicarpus are consistent with the subfunctionalization of JFT paralogs across a partitioned venom system within the colony, such that each JFT is expressed within a specific set of functionally distinct polyp types and, in some cases, specific nematocyst types.

Highly Evolvable: Investigating Interspecific and Intraspecific Venom Variation in Taipans (Oxyuranus spp.) and Brown Snakes (Pseudonaja spp.).

Snake venoms are complex mixtures of toxins that differ on interspecific (between species) and intraspecific (within species) levels. Whether venom variation within a group of closely related species is explained by the presence, absence and/or relative abundances of venom toxins remains largely unknown. Taipans (Oxyuranus spp.) and brown snakes (Pseudonaja spp.) represent medically relevant species of snakes across the Australasian region and provide an excellent model clade for studying interspecific and intraspecific venom variation. Using liquid chromatography with ultraviolet and mass spectrometry detection, we analyzed a total of 31 venoms covering all species of this monophyletic clade, including widespread localities. Our results reveal major interspecific and intraspecific venom variation in Oxyuranus and Pseudonaja species, partially corresponding with their geographical regions and phylogenetic relationships. This extensive venom variability is generated by a combination of the absence/presence and differential abundance of venom toxins. Our study highlights that venom systems can be highly dynamical on the interspecific and intraspecific levels and underscores that the rapid toxin evolvability potentially causes major impacts on neglected tropical snakebites.