title: Melt With This Kiss: Paralyzing and Liquefying Venom of The Assassin BugPristhesancus plagipennis(Hemiptera: Reduviidae).
abstract: Assassin bugs (Hemiptera: Heteroptera: Reduviidae) are venomous insects, most of which prey on invertebrates. Assassin bug venom has features in common with venoms from other animals, such as paralyzing and lethal activity when injected, and a molecular composition that includes disulfide-rich peptide neurotoxins. Uniquely, this venom also has strong liquefying activity that has been hypothesized to facilitate feeding through the narrow channel of the proboscis-a structure inherited from sap- and phloem-feeding phytophagous hemipterans and adapted during the evolution of Heteroptera into a fang and feeding structure. However, further understanding of the function of assassin bug venom is impeded by the lack of proteomic studies detailing its molecular composition.By using a combined transcriptomic/proteomic approach, we show that the venom proteome of the harpactorine assassin bugPristhesancus plagipennisincludes a complex suite of >100 proteins comprising disulfide-rich peptides, CUB domain proteins, cystatins, putative cytolytic toxins, triabin-like protein, odorant-binding protein, S1 proteases, catabolic enzymes, putative nutrient-binding proteins, plus eight families of proteins without homology to characterized proteins. S1 proteases, CUB domain proteins, putative cytolytic toxins, and other novel proteins in the 10-16-kDa mass range, were the most abundant venom components. Thus, in addition to putative neurotoxins, assassin bug venom includes a high proportion of enzymatic and cytolytic venom components likely to be well suited to tissue liquefaction. Our results also provide insight into the trophic switch to blood-feeding by the kissing bugs (Reduviidae: Triatominae). Although some protein families such as triabins occur in the venoms of both predaceous and blood-feeding reduviids, the composition of venoms produced by these two groups is revealed to differ markedly. These results provide insights into the venom evolution in the insect suborder Heteroptera.
authors.affiliation: From the ‡Institute for Molecular Bioscience, a.walker@uq.edu.au glenn.king@imb.uq.edu.au.
authors.forename: Andrew A
authors.identifier: 0000-0003-1296-6593
authors.initials: AA
authors.lastname: Walker
authors.affiliation: From the ‡Institute for Molecular Bioscience.
authors.forename: Bruno
authors.initials: B
authors.lastname: Madio
authors.affiliation: From the ‡Institute for Molecular Bioscience.
authors.forename: Jiayi
authors.initials: J
authors.lastname: Jin
authors.affiliation: ¶Centre for Advanced Imaging, and.
authors.forename: Eivind A B
authors.initials: EA
authors.lastname: Undheim
authors.affiliation: ‖School of Biological Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia.
authors.forename: Bryan G
authors.initials: BG
authors.lastname: Fry
authors.affiliation: From the ‡Institute for Molecular Bioscience, a.walker@uq.edu.au glenn.king@imb.uq.edu.au.
authors.forename: Glenn F
authors.initials: GF
authors.lastname: King
mesh_terms: D000818:Animals; D001180:Arthropod Venoms / Q000235:genetics* / Q000378:metabolism*; D019143:Evolution, Molecular; D020869:Gene Expression Profiling / Q000379:methods; D010802:Phylogeny; D040901:Proteomics / Q000379:methods; D020064:Reduviidae / Q000235:genetics / Q000378:metabolism*; D017423:Sequence Analysis, RNA
chemical_list: D001180:Arthropod Venoms