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Duran LH, Wilson DT, Salih M, Rymer TL. Interactions between physiology and behaviour provide insights into the ecological role of venom in Australian funnel-web spiders: Interspecies comparison. PLoS One 2023; 18:e0285866. [PMID: 37216354 PMCID: PMC10202279 DOI: 10.1371/journal.pone.0285866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 05/03/2023] [Indexed: 05/24/2023] Open
Abstract
Australian funnel-web spiders are iconic species, characterized as being the most venomous spiders in the world. They are also valued for the therapeutics and natural bioinsecticides potentially hidden in their venom molecules. Although numerous biochemical and molecular structural approaches have tried to determine the factors driving venom complexity, these approaches have not considered behaviour, physiology and environmental conditions collectively, which can play a role in the evolution, complexity, and function of venom components in funnel-webs. This study used a novel interdisciplinary approach to understand the relationships between different behaviours (assessed in different ecological contexts) and morphophysiological variables (body condition, heart rate) that may affect venom composition in four species of Australian funnel-web spiders. We tested defensiveness, huddling behaviour, frequency of climbing, and activity for all species in three ecological contexts: i) predation using both indirect (puff of air) and direct (prodding) stimuli; ii) conspecific tolerance; and iii) exploration of a new territory. We also assessed morphophysiological variables and venom composition of all species. For Hadronyche valida, the expression of some venom components was associated with heart rate and defensiveness during the predation context. However, we did not find any associations between behavioural traits and morphophysiological variables in the other species, suggesting that particular associations may be species-specific. When we assessed differences between species, we found that the species separated out based on the venom profiles, while activity and heart rate are likely more affected by individual responses and microhabitat conditions. This study demonstrates how behavioural and morphophysiological traits are correlated with venom composition and contributes to a broader understanding of the function and evolution of venoms in funnel-web spiders.
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Affiliation(s)
- Linda Hernández Duran
- College of Science and Engineering, James Cook University, Cairns, Australia
- Centre for Tropical Environmental and Sustainability Sciences, James Cook University, Cairns, Australia
- Australian Institute for Tropical Health and Medicine, Centre for Molecular Therapeutics, James Cook University, Cairns, Australia
| | - David Thomas Wilson
- Australian Institute for Tropical Health and Medicine, Centre for Molecular Therapeutics, James Cook University, Cairns, Australia
| | - Mohamed Salih
- Department of Obstetrics and Gynaecology, Monash University, Clayton, Victoria, Australia
| | - Tasmin Lee Rymer
- College of Science and Engineering, James Cook University, Cairns, Australia
- Centre for Tropical Environmental and Sustainability Sciences, James Cook University, Cairns, Australia
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2
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The Deadly Toxin Arsenal of the Tree-Dwelling Australian Funnel-Web Spiders. Int J Mol Sci 2022; 23:ijms232113077. [PMID: 36361863 PMCID: PMC9658043 DOI: 10.3390/ijms232113077] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 11/23/2022] Open
Abstract
Australian funnel-web spiders are amongst the most dangerous venomous animals. Their venoms induce potentially deadly symptoms, including hyper- and hypotension, tachycardia, bradycardia and pulmonary oedema. Human envenomation is more frequent with the ground-dwelling species, including the infamous Sydney funnel-web spider (Atrax robustus); although, only two tree-dwelling species induce more severe envenomation. To unravel the mechanisms that lead to this stark difference in clinical outcomes, we investigated the venom transcriptome and proteome of arboreal Hadronyche cerberea and H. formidabilis. Overall, Hadronyche venoms comprised 44 toxin superfamilies, with 12 being exclusive to tree-dwellers. Surprisingly, the major venom components were neprilysins and uncharacterized peptides, in addition to the well-known ω- and δ-hexatoxins and double-knot peptides. The insecticidal effects of Hadronyche venom on sheep blowflies were more potent than Atrax venom, and the venom of both tree- and ground-dwelling species potently modulated human voltage-gated sodium channels, particularly NaV1.2. Only the venom of tree-dwellers exhibited potent modulation of voltage-gated calcium channels. H. formidabilis appeared to be under less diversifying selection pressure compared to the newly adapted tree-dweller, H. cerberea. Thus, this study contributes to unravelling the fascinating molecular and pharmacological basis for the severe envenomation caused by the Australian tree-dwelling funnel-web spiders.
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Australian funnel-web spiders evolved human-lethal δ-hexatoxins for defense against vertebrate predators. Proc Natl Acad Sci U S A 2020; 117:24920-24928. [PMID: 32958636 DOI: 10.1073/pnas.2004516117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Australian funnel-web spiders are infamous for causing human fatalities, which are induced by venom peptides known as δ-hexatoxins (δ-HXTXs). Humans and other primates did not feature in the prey or predator spectrum during evolution of these spiders, and consequently the primate lethality of δ-HXTXs remains enigmatic. Funnel-web envenomations are mostly inflicted by male spiders that wander from their burrow in search of females during the mating season, which suggests a role for δ-HXTXs in self-defense since male spiders rarely feed during this period. Although 35 species of Australian funnel-web spiders have been described, only nine δ-HXTXs from four species have been characterized, resulting in a lack of understanding of the ecological roles and molecular evolution of δ-HXTXs. Here, by profiling venom-gland transcriptomes of 10 funnel-web species, we report 22 δ-HXTXs. Phylogenetic and evolutionary assessments reveal a remarkable sequence conservation of δ-HXTXs despite their deep evolutionary origin within funnel-web spiders, consistent with a defensive role. We demonstrate that δ-HXTX-Ar1a, the lethal toxin from the Sydney funnel-web spider Atrax robustus, induces pain in mice by inhibiting inactivation of voltage-gated sodium (NaV) channels involved in nociceptive signaling. δ-HXTX-Ar1a also inhibited inactivation of cockroach NaV channels and was insecticidal to sheep blowflies. Considering their algogenic effects in mice, potent insecticidal effects, and high levels of sequence conservation, we propose that the δ-HXTXs were repurposed from an initial insecticidal predatory function to a role in defending against nonhuman vertebrate predators by male spiders, with their lethal effects on humans being an unfortunate evolutionary coincidence.
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Isbister GK, Warner G. Acute Myocardial Injury Caused by Sydney Funnel-web Spider (Atrax robustus) Envenoming. Anaesth Intensive Care 2019; 31:672-4. [PMID: 14719431 DOI: 10.1177/0310057x0303100612] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A 67-year-old female suffered envenoming by a Sydney funnel-web spider (Atrax robustus ), complicated by ST elevation and elevated troponin levels consistent with an acute myocardial injury. She was treated primarily with funnel-web spider antivenom, admission to intensive care and initial respiratory support for acute pulmonary oedema. The mechanism by which funnel-web spider envenomation caused myocardial injury is unclear but follow-up nuclear studies in the patient demonstrated that she had minimal atherosclerotic disease.
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Affiliation(s)
- G K Isbister
- Newcastle Mater Misericordiae Hospital, Waratah, New South Wales
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5
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Clinical consequences of toxic envenomation by spiders. Toxicon 2018; 152:65-70. [DOI: 10.1016/j.toxicon.2018.07.021] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 07/17/2018] [Accepted: 07/22/2018] [Indexed: 01/17/2023]
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6
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Hedin M, Derkarabetian S, Ramírez MJ, Vink C, Bond JE. Phylogenomic reclassification of the world's most venomous spiders (Mygalomorphae, Atracinae), with implications for venom evolution. Sci Rep 2018; 8:1636. [PMID: 29374214 PMCID: PMC5785998 DOI: 10.1038/s41598-018-19946-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 01/10/2018] [Indexed: 12/27/2022] Open
Abstract
Here we show that the most venomous spiders in the world are phylogenetically misplaced. Australian atracine spiders (family Hexathelidae), including the notorious Sydney funnel-web spider Atrax robustus, produce venom peptides that can kill people. Intriguingly, eastern Australian mouse spiders (family Actinopodidae) are also medically dangerous, possessing venom peptides strikingly similar to Atrax hexatoxins. Based on the standing morphology-based classification, mouse spiders are hypothesized distant relatives of atracines, having diverged over 200 million years ago. Using sequence-capture phylogenomics, we instead show convincingly that hexathelids are non-monophyletic, and that atracines are sister to actinopodids. Three new mygalomorph lineages are elevated to the family level, and a revised circumscription of Hexathelidae is presented. Re-writing this phylogenetic story has major implications for how we study venom evolution in these spiders, and potentially genuine consequences for antivenom development and bite treatment research. More generally, our research provides a textbook example of the applied importance of modern phylogenomic research.
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Affiliation(s)
- Marshal Hedin
- Department of Biology, San Diego State University, San Diego, CA, 92182-4614, USA.
| | - Shahan Derkarabetian
- Department of Biology, San Diego State University, San Diego, CA, 92182-4614, USA
- Department of Biology, University of California Riverside, Riverside, California, 92521, USA
| | - Martín J Ramírez
- Division of Arachnology Museo Argentino de Ciencias Naturales "Bernardino Rivadavia" Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) Ciudad Autónoma de Buenos Aires, Buenos Aires, Argentina
| | - Cor Vink
- Canterbury Museum Christchurch, Christchurch, 8013, New Zealand
| | - Jason E Bond
- Department of Biological Sciences, Auburn University, Auburn, AL, 36849, USA
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Yang DC, Deuis JR, Dashevsky D, Dobson J, Jackson TNW, Brust A, Xie B, Koludarov I, Debono J, Hendrikx I, Hodgson WC, Josh P, Nouwens A, Baillie GJ, Bruxner TJC, Alewood PF, Lim KKP, Frank N, Vetter I, Fry BG. The Snake with the Scorpion's Sting: Novel Three-Finger Toxin Sodium Channel Activators from the Venom of the Long-Glanded Blue Coral Snake (Calliophis bivirgatus). Toxins (Basel) 2016; 8:E303. [PMID: 27763551 PMCID: PMC5086663 DOI: 10.3390/toxins8100303] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 10/04/2016] [Accepted: 10/10/2016] [Indexed: 02/06/2023] Open
Abstract
Millions of years of evolution have fine-tuned the ability of venom peptides to rapidly incapacitate both prey and potential predators. Toxicofera reptiles are characterized by serous-secreting mandibular or maxillary glands with heightened levels of protein expression. These glands are the core anatomical components of the toxicoferan venom system, which exists in myriad points along an evolutionary continuum. Neofunctionalisation of toxins is facilitated by positive selection at functional hotspots on the ancestral protein and venom proteins have undergone dynamic diversification in helodermatid and varanid lizards as well as advanced snakes. A spectacular point on the venom system continuum is the long-glanded blue coral snake (Calliophis bivirgatus), a specialist feeder that preys on fast moving, venomous snakes which have both a high likelihood of prey escape but also represent significant danger to the predator itself. The maxillary venom glands of C. bivirgatus extend one quarter of the snake's body length and nestle within the rib cavity. Despite the snake's notoriety its venom has remained largely unstudied. Here we show that the venom uniquely produces spastic paralysis, in contrast to the flaccid paralysis typically produced by neurotoxic snake venoms. The toxin responsible, which we have called calliotoxin (δ-elapitoxin-Cb1a), is a three-finger toxin (3FTx). Calliotoxin shifts the voltage-dependence of NaV1.4 activation to more hyperpolarised potentials, inhibits inactivation, and produces large ramp currents, consistent with its profound effects on contractile force in an isolated skeletal muscle preparation. Voltage-gated sodium channels (NaV) are a particularly attractive pharmacological target as they are involved in almost all physiological processes including action potential generation and conduction. Accordingly, venom peptides that interfere with NaV function provide a key defensive and predatory advantage to a range of invertebrate venomous species including cone snails, scorpions, spiders, and anemones. Enhanced activation or delayed inactivation of sodium channels by toxins is associated with the extremely rapid onset of tetanic/excitatory paralysis in envenomed prey animals. A strong selection pressure exists for the evolution of such toxins where there is a high chance of prey escape. However, despite their prevalence in other venomous species, toxins causing delay of sodium channel inhibition have never previously been described in vertebrate venoms. Here we show that NaV modulators, convergent with those of invertebrates, have evolved in the venom of the long-glanded coral snake. Calliotoxin represents a functionally novel class of 3FTx and a structurally novel class of NaV toxins that will provide significant insights into the pharmacology and physiology of NaV. The toxin represents a remarkable case of functional convergence between invertebrate and vertebrate venom systems in response to similar selection pressures. These results underscore the dynamic evolution of the Toxicofera reptile system and reinforces the value of using evolution as a roadmap for biodiscovery.
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Affiliation(s)
- Daryl C Yang
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton 3168, Australia.
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Jennifer R Deuis
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
| | - Daniel Dashevsky
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - James Dobson
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Timothy N W Jackson
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Andreas Brust
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
| | - Bing Xie
- Bejing Genomics Institute-Shenzhen, Shenzhen 518083, China.
| | - Ivan Koludarov
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Jordan Debono
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Iwan Hendrikx
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
| | - Wayne C Hodgson
- Department of Pharmacology, Biomedicine Discovery Institute, Monash University, Clayton 3168, Australia.
| | - Peter Josh
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia 4072, Australia.
| | - Amanda Nouwens
- School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia 4072, Australia.
| | - Gregory J Baillie
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
| | - Timothy J C Bruxner
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
| | - Paul F Alewood
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
| | - Kelvin Kok Peng Lim
- Lee Kong Chian Natural History Museum, National University of Singapore, 2 Conservatory Drive, Singapore 117377, Singapore.
| | | | - Irina Vetter
- Institute for Molecular Bioscience, University of Queensland, St. Lucia 4072, Australia.
- School of Pharmacy, University of Queensland, Woolloongabba 4102, Australia.
| | - Bryan G Fry
- Venom Evolution Lab, School of Biological Sciences, University of Queensland, St. Lucia 4072, Australia.
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8
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Palagi A, Koh JM, Leblanc M, Wilson D, Dutertre S, King GF, Nicholson GM, Escoubas P. Unravelling the complex venom landscapes of lethal Australian funnel-web spiders (Hexathelidae: Atracinae) using LC-MALDI-TOF mass spectrometry. J Proteomics 2013; 80:292-310. [DOI: 10.1016/j.jprot.2013.01.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 01/04/2013] [Accepted: 01/07/2013] [Indexed: 10/27/2022]
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Abstract
Spiders are a source of intrigue and fear, and several myths exist about their medical effects. Many people believe that bites from various spider species cause necrotic ulceration, despite evidence that most suspected cases of necrotic arachnidism are caused by something other than a spider bite. Latrodectism and loxoscelism are the most important clinical syndromes resulting from spider bite. Latrodectism results from bites by widow spiders (Latrodectus spp) and causes local, regional, or generalised pain associated with non-specific symptoms and autonomic effects. Loxoscelism is caused by Loxosceles spp, and the cutaneous form manifests as pain and erythema that can develop into a necrotic ulcer. Systemic loxoscelism is characterised by intravascular haemolysis and renal failure on occasion. Other important spiders include the Australian funnel-web spider (Atrax spp and Hadronyche spp) and the armed spider (Phoneutria spp) from Brazil. Antivenoms are an important treatment for spider envenomation but have been less successful than have those for snake envenomation, with concerns about their effectiveness for both latrodectism and loxoscelism.
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Affiliation(s)
- Geoffrey K Isbister
- Discipline of Clinical Pharmacology, University of Newcastle, Newcastle, NSW, Australia; Department of Clinical Toxicology and Pharmacology, Calvary Mater Newcastle, Newcastle, NSW, Australia.
| | - Hui Wen Fan
- Centro de Desenvolvimento Cultural, Instituto Butantan, São Paulo, Brazil
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Nayar R, Tehrani H, Nelson K, Khan I. Osteo-cutaneous necrosis following a spider bite to the thumb. EUROPEAN JOURNAL OF PLASTIC SURGERY 2009. [DOI: 10.1007/s00238-009-0353-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Rocha-e-Silva TA, Sutti R, Hyslop S. Milking and partial characterization of venom from the Brazilian spider Vitalius dubius (Theraphosidae). Toxicon 2009; 53:153-61. [DOI: 10.1016/j.toxicon.2008.10.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Revised: 10/30/2008] [Accepted: 10/31/2008] [Indexed: 11/15/2022]
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14
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Rosengren D, White J, Raven R, Rothwell S. First report of a funnel-web spider envenoming syndrome in Brisbane. Emerg Med Australas 2008; 20:164-6. [DOI: 10.1111/j.1742-6723.2008.01069.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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15
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Herzig V, Hodgson WC. Neurotoxic and insecticidal properties of venom from the Australian theraphosid spider Selenotholus foelschei. Neurotoxicology 2008; 29:471-5. [PMID: 18423874 DOI: 10.1016/j.neuro.2008.03.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2007] [Revised: 03/05/2008] [Accepted: 03/05/2008] [Indexed: 11/30/2022]
Abstract
The present study is the first report on the bioactivity of venom from the Australian theraphosid spider Selenotholus foelschei. Venom from female specimens was used in all experiments. Adult spiders yielded an average of 2.2 mg dried venom per milking with a maximum yield of 7.2 mg. To evaluate the activity of pooled S. foelschei venom in invertebrates, a toxicity test in crickets (Acheta domesticus) was used. The results suggest the presence of several insecticidal toxins with different but synergistic modes of action, leading to a fast onset of paralysis as well as persistent paralysis and lethal effects (starting at 4 h after injection) in crickets. Vertebrate activity of S. foelschei venom was tested by using the isolated chick biventer cervicis nerve-muscle preparation. The venom produced a significant reduction in baseline tension (at a concentration of 10 microg/mL) and twitch height (at 0.2-10 microg/mL). Twitches were not restored after repeated washing. The response of the muscle to exogenous acetylcholine (1 mM) and carbachol (0.02 mM) was not reduced by the venom. These results indicate the presence of a vertebrate-active neurotoxin in S. foelschei that irreversibly blocks muscle twitches by acting either on voltage-activated Na(+)-channels or on other pre-synaptically located receptors.
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Affiliation(s)
- Volker Herzig
- Monash Venom Group, Department of Pharmacology, Monash University, Clayton Campus, Clayton, VIC, Australia.
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Nicholson GM, Graudins A, Wilson HI, Little M, Broady KW. Arachnid toxinology in Australia: From clinical toxicology to potential applications. Toxicon 2006; 48:872-98. [PMID: 16934848 DOI: 10.1016/j.toxicon.2006.07.025] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The unique geographic isolation of Australia has resulted in the evolution of a distinctive range of Australian arachnid fauna. Through the pioneering work of a number of Australian arachnologists, toxinologists, and clinicians, the taxonomy and distribution of new species, the effective clinical treatment of envenomation, and the isolation and characterisation of the many distinctive neurotoxins, has been achieved. In particular, work has focussed on several Australian arachnids, including red-back and funnel-web spiders, paralysis ticks, and buthid scorpions that contain neurotoxins capable of causing death or serious systemic envenomation. In the case of spiders, species-specific antivenoms have been developed to treat envenomed patients that show considerable cross-reactivity. Both in vitro and clinical case studies have shown they are particularly efficacious in the treatment of envenomation by spiders even from unrelated families. Despite their notorious reputation, the high selectivity and potency of a unique range of toxins from the venom of Australian arachnids will make them invaluable molecular tools for studies of neurotransmitter release and vesicle exocytosis as well as ion channel structure and function. The venoms of funnel-web spiders, and more recently Australian scorpions, have also provided a previously untapped rich source of insect-selective neurotoxins for the future development of biopesticides and the characterisation of previously unvalidated insecticide targets. This review provides a historical viewpoint of the work of many toxinologists to isolate and characterise just some of the toxins produced by such a unique group of arachnids and examines the potential applications of these novel peptides.
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Affiliation(s)
- Graham M Nicholson
- Neurotoxin Research Group, Department of Medical & Molecular Biosciences, University of Technology, Sydney, P.O. Box 123, City Campus, Broadway, NSW 2007, Australia.
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17
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Abstract
The complex nature of venom from spider species offers a unique natural source of potential pharmacological tools and therapeutic leads. The increased interest in spider venom molecules requires reproducible and precise identification methods. The current taxonomy of the Australian Funnel-web spiders is incomplete, and therefore, accurate identification of these spiders is difficult. Here, we present a study of venom from numerous morphologically similar specimens of the Hadronyche infensa species group collected from a variety of geographic locations in southeast Queensland. Analysis of the crude venoms using online reversed-phase high performance liquid chromatography/electrospray ionisation mass spectrometry (rp-HPLC/ESI-MS) revealed that the venom profiles provide a useful means of specimen identification, from the species level to species variants. Tables defining the descriptor molecules for each group of specimens were constructed and provided a quick reference of the relationship between one specimen and another. The study revealed that the morphologically similar specimens from the southeast Queensland region are a number of different species/species variants. Furthermore, the study supports aspects of the current taxonomy with respect to the H. infensa species group. Analysis of Australian Funnel-web spider venom by rp-HPLC/ESI-MS provides a rapid and accurate method of species/species variant identification.
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Affiliation(s)
- David Wilson
- Xenome Ltd, P.O. Box 6295, St Lucia, Qld 4067, Australia.
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18
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Isbister GK, Gray MR, Balit CR, Raven RJ, Stokes BJ, Porges K, Tankel AS, Turner E, White J, Fisher MM. Funnel-web spider bite: a systematic review of recorded clinical cases. Med J Aust 2005; 182:407-11. [PMID: 15850438 DOI: 10.5694/j.1326-5377.2005.tb06760.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2004] [Accepted: 02/07/2005] [Indexed: 11/17/2022]
Abstract
OBJECTIVE To investigate species-specific envenoming rates and spectrum of severity of funnel-web spider bites, and the efficacy and adverse effects of funnel-web spider antivenom. DATA SOURCES Cases were identified from a prospective study of spider bite presenting to four major hospitals and three state poisons information centres (1999-2003); museum records of spider specimens since 1926; NSW Poisons Information Centre database; MEDLINE and EMBASE search; clinical toxinology textbooks; the media; and the manufacturer's reports of antivenom use. DATA EXTRACTION Patient age and sex, geographical location, month, expert identification of the spider, clinical effects and management; envenoming was classified as severe, mild-moderate or minor/local effects. DATA SYNTHESIS 198 potential funnel-web spider bites were identified: 138 were definite (spider expertly identified to species or genus), and 77 produced severe envenoming. All species-identified severe cases were attributed to one of six species restricted to NSW and southern Queensland. Rates of severe envenoming were: Hadronyche cerberea (75%), H. formidabilis (63%), Atrax robustus (17%), Hadronyche sp. 14 (17%), H. infensa (14%) and H. versuta (11%). Antivenom was used in 75 patients, including 22 children (median dose, 3 ampoules; range, 1-17), with a complete response in 97% of expertly identified cases. Three adverse reactions were reported, all in adults: two early allergic reactions (one mild and one with severe systemic effects requiring adrenaline), and one case of serum sickness. CONCLUSIONS Severe funnel-web spider envenoming is confined to NSW and southern Queensland; tree-dwelling funnel webs (H. cerberea and H. formidabilis) have the highest envenoming rates. Funnel-web spider antivenom appears effective and safe; severe allergic reactions are uncommon.
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Abstract
Bites, stings and infestations can be fatal. Anaphylaxis to vespids and bees can be prevented with immunotherapy. Patients should be referred to an allergist. The acute care and prevention of arthropod injury is discussed below.
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Affiliation(s)
- Dirk M Elston
- Department of Dermatology, Geisinger Medical Center, Danville, PA 17821, USA.
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20
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Abstract
Citation of a published work is one of the parameters considered in the analysis of relevance and importance of scientific contributions. In 2002, for the first time the Impact Factor of Toxicon has risen above 2.0, placing it at the 17th position among 76 journals in the 'toxicology' field. The aim of this article was to identify the most cited articles in Toxicon, that have contributed to the steady increase of its Impact Factor. The number of citations, complete reference and type of all documents appearing in Toxicon in the period 1963-2003 were retrieved from the ISI Web-of-Science homepage. The documents retrieved were sorted by the number of citations received. A 'citation index', defined as the number of citations divided by the number of years since publication, was calculated for each document. It was clearly seen that reviews in Toxicon received 4.4-fold more citations than articles. Unexpectedly, it was found that recent papers were proportionally more cited than old ones. A decrease in the proportion of papers dealing on 'snake*' through out the period and the broadened range of subjects of the most cited papers recently published in Toxicon reflects an increased 'visibility' in other fields of toxinology. Research on plant toxins gained its own space in Toxicon with newer publications showing high citation indexes. It can be postulated that these facts helped to increase Toxicon's Impact Factor from 1.248 in 1999 to 2.003 in 2002. With the increased number of issues in Toxicon as well as publications of subject-dedicated volumes containing mostly reviews, the Impact Factor of Toxicon is expected to keep rising in the near future.
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Affiliation(s)
- Jorge A Guimarães
- Center of Biotechnology, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9500, Prédio 43.421, CEP 91501970 Porto Alegre, RS, Brazil
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Abstract
Spider bite continues to be a controversial subject worldwide and attribution of clinical effects to different spiders is problematic because of poor case definition and paucity of clinical evidence. The effects of medically important spiders are sometimes underestimated and simultaneously there is misattribution of effects to harmless spider groups. The majority of suspected spider bites present as skin lesions or necrotic ulcers where the history of a spider bite must be confirmed. To be a definite spider bite, the patient must immediately observe the spider and there be evidence of the bite, such as pain. Important groups of spiders worldwide include the widow spiders (latrodectism), recluse spiders (loxoscelism) and some mygalomorph spiders including the Australian Funnel web spider. Most spiders only cause minor effects, including a large number of groups that have been implicated in necrotic arachnidism.
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Affiliation(s)
- Geoffrey K Isbister
- Emergency Department, Newcastle Mater Misericordiae Hospital and the University of Newcastle, Newcastle, NSW 2298, Australia.
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22
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Nicholson GM, Little MJ, Birinyi-Strachan LC. Structure and function of δ-atracotoxins: lethal neurotoxins targeting the voltage-gated sodium channel. Toxicon 2004; 43:587-99. [PMID: 15066415 DOI: 10.1016/j.toxicon.2004.02.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Delta-atracotoxins (delta-ACTX), isolated from the venom of Australian funnel-web spiders, are responsible for the potentially lethal envenomation syndrome seen following funnel-web spider envenomation. They are 42-residue polypeptides with four disulfides and an "inhibitor cystine-knot" motif with structural but not sequence homology to a variety of other spider and marine snail toxins. Delta-atracotoxins induce spontaneous repetitive firing and prolongation of action potentials resulting in neurotransmitter release from somatic and autonomic nerve endings. This results from a slowing of voltage-gated sodium channel inactivation and a hyperpolarizing shift of the voltage-dependence of activation. This action is due to voltage-dependent binding to neurotoxin receptor site-3 in a similar, but not identical, fashion to scorpion alpha-toxins and sea anemone toxins. Unlike other site-3 neurotoxins, however, delta-ACTX bind with high affinity to both cockroach and mammalian sodium channels but low affinity to locust sodium channels. At present the pharmacophore of delta-ACTX is unknown but is believed to involve a number of basic residues distributed in a topologically similar manner to scorpion alpha-toxins and sea anemone toxins despite distinctly different protein scaffolds. As such, delta-ACTX provide us with specific tools with which to study sodium channel structure and function and determinants for phyla- and tissue-specific actions of neurotoxins interacting with site-3.
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Affiliation(s)
- Graham M Nicholson
- Neurotoxin Research Group, Department of Heath Sciences, University of Technology, Sydney, PO Box 123, Broadway, NSW 2007, Australia.
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Isbister GK, Gray MR. Bites by Australian mygalomorph spiders (Araneae, Mygalomorphae), including funnel-web spiders (Atracinae) and mouse spiders (Actinopodidae: Missulena spp). Toxicon 2004; 43:133-40. [PMID: 15019472 DOI: 10.1016/j.toxicon.2003.11.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2003] [Indexed: 11/21/2022]
Abstract
A number of mygalomorph spiders cause bites in Australia, including the funnel-web spiders (Hexathelidae, Atracinae: Hadronyche and Atrax) and mouse spiders (Actinopodidae: Missulena). There is ongoing debate about the significance of bites by mouse spiders and the frequency of severe envenoming by funnel-web spiders. We conducted a prospective cohort study of definite spider bites with expert spider identification and include the analysis of mygalomorph spiders here. Subjects were recruited prospectively from February 1999 to April 2003 from patients presenting to participating hospitals or contacting a state poison information centre. Forty-nine cases of bites by mygalomorph spiders were included: 16 were by funnel-web spiders, 13 by mouse spiders and 20 by other trapdoor spiders (Families Idiopidae and Nemesiidae). Of the 49 bites, 45 (92%) occurred on distal limbs (hands and feet). Local effects included severe pain (53%), puncture marks (61%) and bleeding (27%), local redness (33%). Itchiness did not occur. The following were highly statistically associated with mygalomorph spider bites compared to all other spiders (p<0.0001) circumstances (gardening at the time (likelihood ratio (LR) 7.9) and distal limb bites (LR 2.0)) and early clinical features (presence of puncture marks OR bleeding (2.3), or severe pain (2.0)). Of 16 funnel-web spider bites, there were 10 cases with minor local effects, four with moderate envenoming (non-specific systemic or local neurotoxicity) and two with severe envenoming requiring antivenom. In addition to local effects, mouse spider bites caused local paraesthesia in three cases, local diaphoresis in one case and non-specific systemic effects in five cases, but not severe envenoming. True trapdoor spider bites caused only minor effects. The data from a mixed species sample of funnel-web spiders confirms previous observations suggesting that only a small proportion of funnel-web bites cause severe effects. Mouse spider bites are unlikely to cause major envenoming but the clinical effects are consistent with neurotoxic venom and are more severe than the trapdoor spiders.
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Affiliation(s)
- Geoffrey K Isbister
- Emergency Department, Newcastle Mater Misericordiae Hospital and the University of Newcastle, The Children's Hospital at Westmead, Sydney, Australia.
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25
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Gunning SJ, Chong Y, Khalife AA, Hains PG, Broady KW, Nicholson GM. Isolation of δ-missulenatoxin-Mb1a, the major vertebrate-active spider δ-toxin from the venom ofMissulena bradleyi(Actinopodidae)1. FEBS Lett 2003; 554:211-8. [PMID: 14596942 DOI: 10.1016/s0014-5793(03)01175-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The present study describes the isolation and pharmacological characterisation of the neurotoxin delta-missulenatoxin-Mb1a (delta-MSTX-Mb1a) from the venom of the male Australian eastern mouse spider, Missulena bradleyi. This toxin was isolated using reverse-phase high-performance liquid chromatography and was subsequently shown to cause an increase in resting tension, muscle fasciculation and a decrease in indirect twitch tension in a chick biventer cervicis nerve-muscle bioassay. Interestingly, these effects were neutralised by antivenom raised against the venom of the Sydney funnel-web spider Atrax robustus. Subsequent whole-cell patch-clamp electrophysiology on rat dorsal root ganglion neurones revealed that delta-MSTX-Mb1a caused a reduction in peak tetrodotoxin (TTX)-sensitive sodium current, a slowing of sodium current inactivation and a hyperpolarising shift in the voltage at half-maximal activation. In addition, delta-MSTX-Mb1a failed to affect TTX-resistant sodium currents. Subsequent Edman degradation revealed a 42-residue peptide with unusual N- and C-terminal cysteines and a cysteine triplet (Cys(14-16)). This toxin was highly homologous to a family of delta-atracotoxins (delta-ACTX) from Australian funnel-web spiders including conservation of all eight cysteine residues. In addition to actions on sodium channel gating and kinetics to delta-ACTX, delta-MSTX-Mb1a caused significant insect toxicity at doses up to 2000 pmol/g. Delta-MSTX-Mb1a therefore provides evidence of a highly conserved spider delta-toxin from a phylogenetically distinct spider family that has not undergone significant modification.
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Affiliation(s)
- Simon J Gunning
- Department of Health Sciences, University of Technology, Sydney, NSW 2007, Australia
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Isbister GK, Graudins A, White J, Warrell D. Antivenom treatment in arachnidism. JOURNAL OF TOXICOLOGY. CLINICAL TOXICOLOGY 2003; 41:291-300. [PMID: 12807312 DOI: 10.1081/clt-120021114] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Envenomation by arachnids causes significant medical illness worldwide. Scorpion sting is the most important arachnid envenomation causing adult morbidity and pediatric mortality. Important groups of spiders include the widow spiders (Latrodectus spp.), the recluse spiders (Loxosceles spp.), and two spiders confined to single countries: the Australian funnel web spider (Atrax and Hadronyche spp.) and the armed spider (Phoneutria spp.) from Brazil. There are four widow spider antivenoms available, including the Australian redback spider antivenom and the American black widow antivenom. Despite good in vitro animal work demonstrating effective neutralization with these antivenoms, and cross-reactivity between many species, there continues to be a reluctance to use them in some countries. They are both associated with a relatively low rate of allergic reactions. Redback antivenom is routinely used by the intramuscular route, which may not be as effective as intravenous use based on clinical experience and animal studies. Antivenoms are available for Loxosceles spp., but there is little evidence to support their effectiveness, particularly against local effects. The Australian funnel web spider causes severe neurotoxic envenomation, and antivenom appears to be effective in reported cases. An antivenom exists for the Brazilian armed spider, but is used in only a minority of cases. Many scorpion antivenoms exist worldwide, but there remains significant controversy regarding their efficacy. Animal and human venom level studies demonstrate neutralization of circulating venom in systemic envenomation. Clinical experience in countries where antivenom has been introduced suggests it has reduced pediatric mortality. However, three controlled trials demonstrated that antivenom was not effective, but these included few severe cases. Until controlled trials of antivenom in systemically envenomated patients are undertaken, antivenom use appears justified in severe envenomation. Although envenomation from arthropods is common, no antivenoms exist for these, excepting Lonomia caterpillars in South America, and Ixodes paralysis ticks in Australia.
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Affiliation(s)
- Geoffrey K Isbister
- Discipline of Clinical Pharmacology, University of Newcastle and Newcastle Mater Misericordiae Hospital, Newcastle, NSW, Australia.
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Nicholson GM, Graudins A. Spiders of medical importance in the Asia-Pacific: atracotoxin, latrotoxin and related spider neurotoxins. Clin Exp Pharmacol Physiol 2002; 29:785-94. [PMID: 12165044 DOI: 10.1046/j.1440-1681.2002.03741.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. The spiders of medical importance in the Asia-Pacific region include widow (family Theridiidae) and Australian funnel-web spiders (subfamily Atracinae). In addition, cupboard (family Theridiidae) and Australian mouse spiders (family Actinopodidae) may contain neurotoxins responsible for serious systemic envenomation. Fortunately, there appears to be extensive cross-reactivity of species-specific widow spider antivenom within the family Theridiidae. Moreover, Sydney funnel-web antivenom has been shown to be effective in the treatment of mouse spider envenomation. 2. alpha-Latrotoxin (alpha-LTx) appears to be the main neurotoxin responsible for the envenomation syndrome known as "latrodectism" following bites from widow spiders. This 120 kDa protein binds to distinct receptors (latrophilin 1 and neurexins) to induce neurotransmitter vesicle exocytosis via both Ca2+-dependent and -independent mechanisms, resulting in vesicle depletion. This appears to involve disruption to a process that normally inhibits vesicle fusion in the absence of Ca2+. Precise elucidation of the mechanism of action of alpha-LTx will lead to a major advancement in our understanding of vesicle exocytosis. 3. delta-Atracotoxins (delta-ACTX) are responsible for the primate-specific envenomation syndrome seen following funnel-web spider envenomation. These peptides induce spontaneous repetitive firing and prolongation of action potentials in excitable cells. This results from a hyperpolarizing shift of the voltage-dependence of activation and a slowing of voltage-gated Na+ channel inactivation. This action is due to voltage-dependent binding to neurotoxin receptor site-3 on insect and mammalian voltage-gated Na+ channels in a manner similar, but not identical, to scorpion alpha-toxins and sea anemone toxins. delta-Atracotoxins provide us with highly specific tools to study Na+ channel structure and function 4. omega- and Janus-faced ACTX, from funnel-web spider venom, are novel neurotoxins that show selective toxicity to insects. In particular omega-ACTX define a new insecticide target due to a specific action to block insect voltage-gated Ca2+ channels. Both these ACTX show promise for the development of baculoviral recombinant biopesticides expressing these toxins for the control of insecticide-resistant agricultural pests. In addition, they should provide valuable tools for the pharmacological and structural characterization of insecticide targets.
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Affiliation(s)
- Graham M Nicholson
- Neurotoxin Research Group, Department of Heath Sciences, University of Technology, PO Box 123, Sydney, Broadway, New South Wales 2007, Australia.
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