Project description:Assassin bugs (Hemiptera: Heteroptera: Reduviidae) are venomous insects that prey on invertebrates. Assassin bug venom has features in common with venoms from other animals, such as paralysing 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 hypothesised 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. In addition, the lack of knowledge regarding venoms of predaceous reduviids limits our understanding of how the venoms of the blood-feeding kissing bugs (Reduviidae: Triatominae) evolved to facilitate hematophagy. By using a combined transcriptomic/proteomic approach we show that the venom proteome of the harpactorine assassin bug Pristhesancus plagipennis includes a complex suite of >100 proteins comprising disulfide-rich peptides, CUB-domain proteins, cystatins, putative cytolytic toxins, triabin-like protein, odorant binding protein, serine proteases, catabolic enzymes, putative nutrient-binding proteins, plus eight families of proteins without homology to characterised proteins. Serine proteases, CUB domain proteins and other novel proteins in the 10–16 kDa mass range, as well as putative cytolytic toxins, 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 well suited to tissue liquefaction. While some protein families such as lipocalin/triabins occur in the venoms of both predaceous and blood-feeding reduviids, the composition of venoms in these two groups differs markedly. These results provide insights into the venom evolution in the insect suborder Heteroptera.
Project description:Both single cell and bulk RNA sequencing was performed on expanding or differentiating snake venom gland organoids (from Aspidelaps Lubricus Cowlesi and Naja Nivea), or tissue (Aspidelaps Lubricus Cowlesi). Bulk RNA sequencing from the snake venom gland, liver and pancreas was performed to construct a de novo transcriptome using Trinity.
Project description:Venom injected at oviposition is crucial for successful reproduction in most parasitoid wasp species (Moreau & Asgari 2015; Poirié et al. 2014). The venom of the pea aphid parasitoid Aphidius ervi was analyzed previously using a combined transcriptomic and proteomic approach (Colinet et al. 2014) and we applied similar methods here to compare the venom composition in Lysiphlebus fabarum, that also used the pea aphid as host. Venom was extracted from the L. fabarum venom gland and analyzed using 1D gel electrophoresis and mass spectrometry. A total of 35 L. fabarum proteins were identified as putative venom proteins using these results combined with available transcriptomic data (Dennis et al. 2017) and the genomic data.
Project description:We used a combined transcriptomic and proteomic approach to characterize the venom of a male and female of the black-back scorpion (Hadrurus spadix).
Project description:While the unique symbiotic relationship between anemonefish and sea anemones is iconic, it is still not fully understood how anemonefish withstand and thrive within this venomous host environment. In this study we used a proteotranscriptomics approach to elucidate the proteinaceous toxin repertoire from the most popular host sea anemone Entacmaea quadricolor. Although 1251 different toxin or toxin-like RNA transcripts were expressed in E.quadricolor tentacles and 2736 proteins were detected in milked venom, only 135 (approx. 10%) of proteins in venom were classified as putative toxins. This work raises the perils of defining a dominant venom type based on transcriptomics data alone in sea anemones, as we found that the dominant venom type differed between the transcriptome and proteome data. Moreover, anemonefishes interact with sea anemone proteins, so it is important when determining the dominant toxin type to examine the peptides and proteins that are present in host sea anemone venom and mucus which anemonefishes are known to interact.
Project description:In the present study, the venom peptidome of the red ant, Manica rubida, was characterized using an integrated transcriptomic and proteomic approach. In addition, insecticidal assays on C18 reversed-phase HPLC venom fractions were conducted on Lucilia caesar blowflies to identify neurotoxic peptides.
Project description:We describe the first comprehensive venom profile of a solitary bee, the European carpenter bee Xylocopa violacea, by using a combined proteo-transcriptomic approach. Transcripts of the venom system are used as specific database to match peptide sequences from mass spectrometry analyses of venom from dissected venom glands and venom injected during a defensive sting. In our analyses, we only discuss the proteo-transcriptomically supported venom components and reveal a diverse venom profile with 43 different protein families of which 32 are identified in the injected venom.
Project description:Diachasmimorpha longicaudata parasitoid wasps carry a symbiotic poxvirus, known as DlEPV, within the female wasp venom gland. We sequenced RNA from venom gland tissue to identify DlEPV orthologs for 3 conserved poxvirus core genes. The DlEPV ORFs identified from this transcriptome were used to design primers for downstream RT-qPCR analysis and RNAi knockdown experiments.
Project description:Background The generalist dipteran pupal parasitoid Nasonia vitripennis injects 79 venom peptides into the host before egg laying. This venom induces several important changes in the host, including developmental arrest, immunosuppression, and alterations to normal metabolism. It is hoped that diverse and potent bioactivities of N. vitripennis venom provide an opportunity for the design of novel acting drugs. However, currently very little is known about the individual functions of N. vitripennis venom peptides and less than half can be bioinformatically annotated. The paucity of annotation information complicates the design of studies that seek to better understand the potential mechanisms underlying the envenomation response. Although the RNA interference system of N. vitripennis provides an opportunity to functionally characterise venom encoding genes, with 79 candidates this represents a daunting task. For this reason we were interested in determining the expression levels of venom encoding genes in the venom gland, such that this information could be used to rank candidate venoms. To do this we carried out deep sequencing of the transcriptome of the venom gland and neighbouring ovary tissue and used RNA-seq to measure expression from the 79 venom encoding genes. The generation of a specific venom gland transcriptome dataset also provides further opportunities to investigate novel features of this highly specialised organ. Results High throughput sequencing and RNA-seq revealed that the highest expressed venom encoding gene in the venom gland was a serine protease called Nasvi2EG007167, which has previously been implicated in the apoptotic activity of N. vitripennis venom. As expected the RNA-seq confirmed that the N. vitripennis venom encoding genes are almost exclusively expressed in the venom gland relative to the neighbouring ovary tissue. Novel peptides appear to perform key roles in N. vitripennis venom function as only four of the highest 15 expressed venom encoding genes are bioinformatically annotationed. The high throughput sequencing data also provided evidence for the existence of an additional 471 novel genes in the Nasonia genome that are expressed in the venom gland and ovary. Finally, metagenomic analysis of venom gland transcripts identified viral transcripts that may play an important part in the N. vitripennis venom function. Conclusions The expression level information provided here for the 79 venom encoding genes provides an unbiased dataset that can be used by the N. vitripennis community to identify high value candidates for further functional characterisation. These candidates represent bioactive peptides that have value in drug development pipelines.
Project description:Callobius koreanus (C.koreanus) is a wandering spider and a member of the Amaurobiidae family, infraorder Araneae. RNA-sequencing was performend for venom gland tissue and whole body except venom gland.