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Genomics Mar 2020Hymenopteran parasitoid wasps are a diverse collection of species that infect arthropod hosts and use factors found in their venoms to manipulate host immune responses,...
Hymenopteran parasitoid wasps are a diverse collection of species that infect arthropod hosts and use factors found in their venoms to manipulate host immune responses, physiology, and behaviour. Whole parasitoid venoms have been profiled using proteomic approaches, and here we present a bioinformatic characterization of the venom protein content from Ganaspis sp. 1, a parasitoid that infects flies of the genus Drosophila. We find evidence that diverse evolutionary processes including multifunctionalization, co-option, gene duplication, and horizontal gene transfer may be acting in concert to drive venom gene evolution in Ganaspis sp.1. One major role of parasitoid wasp venom is host immune evasion. We previously demonstrated that Ganaspis sp. 1 venom inhibits immune cell activation in infected Drosophila melanogaster hosts, and our current analysis has uncovered additional predicted virulence functions. Overall, this analysis represents an important step towards understanding the composition and activity of parasitoid wasp venoms.
Topics: Animals; Arthropod Venoms; Drosophila melanogaster; Evolution, Molecular; Gene Duplication; Gene Transfer, Horizontal; Immune Evasion; Proteome; Wasps
PubMed: 31247332
DOI: 10.1016/j.ygeno.2019.06.022 -
Toxicon : Official Journal of the... Jun 2018Among venomous animals, Hymenoptera have been suggested as a rich source of natural toxins. Due to their broad ecological diversity, venom from Hymenoptera insects... (Review)
Review
Among venomous animals, Hymenoptera have been suggested as a rich source of natural toxins. Due to their broad ecological diversity, venom from Hymenoptera insects (bees, wasps and ants) have evolved differentially thus widening the types and biological functions of their components. To date, insect toxinology analysis have scarcely uncovered the complex composition of bee, wasp and ant venoms which include low molecular weight compounds, highly abundant peptides and proteins, including several allergens. In Hymenoptera, these complex mixtures of toxins represent a potent arsenal of biological weapons that are used for self-defense, to repel intruders and to capture prey. Consequently, Hymenoptera venom components have a broad range of pharmacological targets and have been extensively studied, as promising sources of new drugs and biopesticides. In addition, the identification and molecular characterization of Hymenoptera venom allergens have allowed for the rational design of component-resolved diagnosis of allergy, finally improving the outcome of venom immunotherapy (VIT). Until recently, a limited number of Hymenoptera venoms had been unveiled due to the technical limitations of the approaches used to date. Nevertheless, the application of novel techniques with high dynamic range has significantly increased the number of identified peptidic and proteinaceous toxins. Considering this, the present review summarizes the current knowledge about the most representative Hymenoptera venom peptides and proteins which are under study for a better understanding of the insect-caused envenoming process and the development of new drugs and biopesticides.
Topics: Animals; Arthropod Venoms; Hymenoptera; Insect Proteins; Peptides
PubMed: 29715467
DOI: 10.1016/j.toxicon.2018.04.029 -
Toxins Jan 2018Predatory robber flies (Diptera, Asilidae) have been suspected to be venomous due to their ability to overpower well-defended prey. However, details of their venom...
Predatory robber flies (Diptera, Asilidae) have been suspected to be venomous due to their ability to overpower well-defended prey. However, details of their venom composition and toxin arsenal remained unknown. Here, we provide a detailed characterization of the venom system of robber flies through the application of comparative transcriptomics, proteomics and functional morphology. Our results reveal asilid venoms to be dominated by peptides and non-enzymatic proteins, and that the majority of components in the crude venom is represented by just ten toxin families, which we have named Asilidin1-10. Contrary to what might be expected for a liquid-feeding predator, the venoms of robber flies appear to be rich in novel peptides, rather than enzymes with a putative pre-digestive role. The novelty of these peptides suggests that the robber fly venom system evolved independently from hematophagous dipterans and other pancrustaceans. Indeed, six Asilidins match no other venom proteins, while three represent known examples of peptide scaffolds convergently recruited to a toxic function. Of these, members of Asilidin1 closely resemble cysteine inhibitor knot peptides (ICK), of which neurotoxic variants occur in cone snails, assassin bugs, scorpions and spiders. Synthesis of one of these putative ICKs, U-Asilidin₁-Mar1a, followed by toxicity assays against an ecologically relevant prey model revealed that one of these likely plays a role as a neurotoxin involved in the immobilization of prey. Our results are fundamental to address these insights further and to understand processes that drive venom evolution in dipterans as well as other arthropods.
Topics: Animals; Arthropod Proteins; Arthropod Venoms; Diptera; Exocrine Glands; Neurotoxins; Peptides; Proteomics; Toxins, Biological; Transcriptome
PubMed: 29303983
DOI: 10.3390/toxins10010029 -
Nursing Standard (Royal College of... May 2016Hymenoptera venom allergy is an immunoglobulin E (IgE)-mediated hypersensitivity to the venom of insects from the Hymenoptera order and is a common cause of anaphylaxis....
Hymenoptera venom allergy is an immunoglobulin E (IgE)-mediated hypersensitivity to the venom of insects from the Hymenoptera order and is a common cause of anaphylaxis. A diagnosis of venom allergy is made by taking an accurate medical, family and social history, alongside specific allergy testing. Systemic reactions to Hymenoptera venom occur in a small proportion of the population; these range from mild to life-threatening in severity. Treatment for local reactions involves the use of cold packs, antihistamines, analgesia and topical corticosteroids to help alleviate swelling, pain and pruritus. Venom immunotherapy is the treatment of choice for reducing the incidence of future anaphylactic reactions in individuals who have signs of respiratory obstruction or hypotension. Venom immunotherapy is the most effective treatment in reduction of life-threatening reactions to venom, and can improve quality of life for individuals. Treatment should only be provided by experienced staff who are able to provide emergency care for anaphylaxis and life-threatening episodes. A risk assessment to deliver treatment should be undertaken before treatment is commenced.
Topics: Anaphylaxis; Animals; Arthropod Venoms; Humans; Hymenoptera; Hypersensitivity; Immunoglobulin E; Insect Bites and Stings; Treatment Outcome; United Kingdom
PubMed: 27224630
DOI: 10.7748/ns.30.39.44.s44 -
Journal of Toxicology. Clinical...The Brown recluse spider has emerged into a potent venomous creature. Loxoscelism and necrotic arachnidism is not an infrequent medical problem. Spiders other than L.... (Review)
Review
The Brown recluse spider has emerged into a potent venomous creature. Loxoscelism and necrotic arachnidism is not an infrequent medical problem. Spiders other than L. reclusa are capable of inflicting painful and persisting necrotic wounds, however, management of the local cutaneous lesions are similar. Systemic complications of loxoscelism appear to be characteristic for spiders of the genus loxosceles. The authors review an indepth discussion of the spider, venom, diagnosis, clinical presentation, laboratory findings, treatment, and prevention. The literature on loxoscelism is contradictory because of the individuality of the reaction. Experience with many patients is the only guide to management of these cases.
Topics: Adrenal Cortex Hormones; Animals; Anti-Inflammatory Agents; Antivenins; Arthropod Venoms; Child; Child, Preschool; Female; Humans; Male; Rabbits; Spider Bites; Spider Venoms; Spiders
PubMed: 6381752
DOI: 10.3109/15563658308990434 -
Toxicon : Official Journal of the... 1996Several major venom allergens from different insects of the Hymenoptera order have been cloned and sequenced by different laboratories. These insects include fire ants,... (Review)
Review
Several major venom allergens from different insects of the Hymenoptera order have been cloned and sequenced by different laboratories. These insects include fire ants, honey bees, hornets, yellowjackets and wasps. These venom allergens have different biochemical functions, but have one feature in common, their varying extents of sequence identity with other proteins in our environment. Our studies in mice suggest that recombinant fragments containing regions of sequence identity of venom allergen(s) and host protein(s) show antigenic cross-reactivity. These studies lead to the hypothesis that cross-reactivity of venom allergens with host proteins promotes the immunogenicity of venom allergens in susceptible people.
Topics: Allergens; Amino Acid Sequence; Animals; Arthropod Venoms; Humans; Hymenoptera; Immunochemistry; Insect Bites and Stings; Mice; Molecular Sequence Data
PubMed: 9028002
DOI: 10.1016/s0041-0101(96)00088-8 -
Toxicon : Official Journal of the... May 2014Venom generally comprises a complex mixture of compounds representing a non-trivial metabolic expense. Accordingly, natural selection should fine-tune the amount of...
Venom generally comprises a complex mixture of compounds representing a non-trivial metabolic expense. Accordingly, natural selection should fine-tune the amount of venom carried within an animal's venom gland(s). The venom supply of scolopendromorph centipedes likely influences their venom use and has implications for the severity of human envenomations, yet we understand very little about their venom yields and the factors influencing them. We investigated how size, specifically body length, influenced volume yield and protein concentration of electrically extracted venom in Scolopendra polymorpha and Scolopendra subspinipes. We also examined additional potential influences on yield in S. polymorpha, including relative forcipule size, relative mass, geographic origin (Arizona vs. California), sex, time in captivity, and milking history. Volume yield was linearly related to body length, and S. subspinipes yielded a larger length-specific volume than S. polymorpha. Body length and protein concentration were uncorrelated. When considering multiple influences on volume yield in S. polymorpha, the most important factor was body length, but yield was also positively associated with relative forcipule length and relative body mass. S. polymorpha from California yielded a greater volume of venom with a higher protein concentration than conspecifics from Arizona, all else being equal. Previously milked animals yielded less venom with a lower protein concentration. For both species, approximately two-thirds of extractable venom was expressed in the first two pulses, with remaining pulses yielding declining amounts, but venom protein concentration did not vary across pulses. Further study is necessary to ascertain the ecological significance of the factors influencing venom yield and how availability may influence venom use.
Topics: Animals; Arizona; Arthropod Venoms; Arthropods; Body Size; California; Electric Stimulation; Female; Male; Poisons; Proteins; Species Specificity
PubMed: 24548696
DOI: 10.1016/j.toxicon.2014.02.003 -
Cellular and Molecular Life Sciences :... Sep 2018True Bugs (Insecta: Heteroptera) produce venom or saliva with diverse bioactivities depending on their feeding strategies. However, little is known about the molecular...
True Bugs (Insecta: Heteroptera) produce venom or saliva with diverse bioactivities depending on their feeding strategies. However, little is known about the molecular evolution of the venom toxins underlying these biological activities. We examined venom of the giant fish-killing water bug Lethocerus distinctifemur (Insecta: Belostomatidae) using infrared spectroscopy, transcriptomics, and proteomics. We report 132 venom proteins including putative enzymes, cytolytic toxins, and antimicrobial peptides. Over 73% (96 proteins) showed homology to venom proteins from assassin bugs (Reduviidae), including 21% (28 proteins from seven families) not known from other sources. These data suggest that numerous protein families were recruited into venom and diversified rapidly following the switch from phytophagy to predation by ancestral heteropterans, and then were retained over > 200 my of evolution. In contrast, trophic switches to blood-feeding (e.g. in Triatominae and Cimicidae) or reversions to plant-feeding (e.g., in Pentatomomorpha) were accompanied by rapid changes in the composition of venom/saliva, including the loss of many protein families.
Topics: Amino Acid Sequence; Animals; Arthropod Venoms; Evolution, Molecular; Fishes; Gene Expression Profiling; Genes, Insect; Heteroptera; Insect Proteins; Phylogeny; Proteomics; Sequence Homology, Amino Acid; Toxins, Biological; Water
PubMed: 29427076
DOI: 10.1007/s00018-018-2768-1 -
Allergy Sep 2022
Topics: Allergens; Anaphylaxis; Animals; Arthropod Venoms; Bee Venoms; Humans; Hymenoptera; Hypersensitivity; Immunoglobulin E; Insect Bites and Stings; Wasp Venoms
PubMed: 35643911
DOI: 10.1111/all.15391 -
Current Opinion in Allergy and Clinical... Aug 2007In this review we will focus on recent advances in the role of mast cells in the pathophysiology of insect allergy and the possible mechanisms of mast cell activation in... (Review)
Review
PURPOSE OF REVIEW
In this review we will focus on recent advances in the role of mast cells in the pathophysiology of insect allergy and the possible mechanisms of mast cell activation in anaphylaxis.
RECENT FINDINGS
Anaphylactic reactions in the mouse can be induced by several independent pathways involving immunoglobulin E, immunoglobulin free light chains, or immunoglobulin G. There is considerable evidence that mast cells play a central role in anaphylactic reactions to insect stings. Mast cells can be directly activated by components of insect venom or after allergic sensitization. Of interest is the observation that mast cells are not only effector cells in insect allergy, but may also play a protective role in preventing the development of severe anaphylactic responses or by controlling inflammatory reactions by modulation of antigen-specific T-cell responses.
SUMMARY
The contribution of mast cells in anaphylactic responses to insect venom may be heterogeneous. On the one hand, activation of mast cells contributes to the pathology by the release of bioactive and tissue-damaging mediators. However, mast cell activation may neutralize constituents in insect venom and defend against the adverse effects of these toxins or they may modulate inflammation through downregulation of antigen-specific immune responses.
Topics: Anaphylaxis; Animals; Animals, Genetically Modified; Arthropod Venoms; Food Hypersensitivity; Guinea Pigs; Immunoglobulin Light Chains; Insect Bites and Stings; Mast Cells; Mice; Models, Animal; Rats
PubMed: 17620830
DOI: 10.1097/ACI.0b013e32825ea543