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:Snake venom gland cDNA sequencing using the Oxford Nanopore MinION with tissue derived from adult venom glands of the painted saw-scaled viper, Echis coloratus
Project description:Snake venoms have evolved in a few families of Caenophidae, and their toxins have been fine-tuned over the evolutive process into highly effective biochemical weapons with a particular role as a trophic adaptation. However, there are many outstanding questions on how venom contributes to the success of venomous species and their adaptation to different environments. Here we analyze the venoms from sympatric and generalist specimens of B. hyoprora, B. taeniatus, B. b. smaragdinus, B. brazili, and B. atrox collected in the wild of Alto Juruá region at the Amazon Forest aiming to understand whether the venom composition could be a driver or influence the arboreal habitats of B. taeniatus and B. b. smaragdinus, or the successful dispersion of B. atrox across the Amazon Forest. Venom composition and the primary sequences of toxin isoforms were characterized by venom gland transcriptomics followed by proteomics. The venom composition of the five species conserved the same protein families present in venoms of Bothropoid snakes but with remarkable differences in the chromatographic profiles and in the relative amount of each toxin group: CTLs were the most abundant in the venoms of B. taeniatus (31.6%), B. b. smaragdinus (33.0%), and B. atrox (32.0%) and SVMPs and PLA2s dominated in venoms of B. hyoprora (23.7% and 20.2%) and B. brazili (20.2% and 20.4%). Some peculiarities were also observed: B. hyoprora venom was the least complex, conserving important isoforms shared with B. atrox venom; the presence of one cluster of SVSPs exclusive to B. brazili venom isoforms; and the presence of the K49-PLA2 homologs only in B. b. smaragdinus and particularly in B. brazili venoms. The SVMP, SVSP, and PLA2 enzyme activities were consistent with the abundance and type of isoforms present in the venoms. B. hyoprora, B. taeniatus, B. b. smaragdinus, and B. atrox venoms presented low lethality to small rodents, while B. brazili venom was the most lethal. Concluding, differences were evidenced between the venoms of B. taeniatus and B. b. smaragdinus arboreal species, while B. b. smaragdinus shared a venom with a similar composition to B. atrox venom, mostly terrestrial. Considering the role of venom toxicity in species' success for adaptation in different areas, B. atrox is the most adapted in the whole Amazonian territory and presented the least lethal venom, while the venom of B. brazili was the most lethal despite its small distribution in the same area. Therefore, our data suggest that the selection of venom composition may not influence the success or behavior of snake species. In this way, other biotic or abiotic factors influence their foraging status or their dispersal in different ecological niches.
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:Venom composition varies across snakes from all taxonomic levels and is influenced by the snakes’ age, habitat, diet, and sexual dimorphism. The present study reports the first in-depth investigation of venom composition in male and female Bothrops moojeni (B. moojeni) snakes (BmooM and BmooF, respectively) through three proteomics approaches associated with functional, cytotoxic, and immunoreactivity characterization. Compared with BmooM venom, BmooF venom exhibited weaker hyaluronidase, metalloproteinase, and phospholipase activity; stronger recognition by anti-bothropic serum; 1.4-fold stronger cytotoxicity; and greater number of peptides. The increased L-amino acid oxidase expression probably accounted for the stronger immunoreactivity and cytotoxicity of BmooF venom. BmooF and BmooM venom shared only 19% peptides. Some venom components were gender-specific, such as phospholipases B, phospholipase inhibitor, and hyaluronidases in BmooM, and cysteine-rich secretory proteins in BmooF. In conclusion, we describe herein the first proteomics study of B. moojeni snake venom and an in-depth characterization of gender-specific differences in venom composition. Altogether, our findings not only stress the importance of considering the snake’s gender during antivenom production, but also help to identify new potential drugs and biotechnological tools.
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:Agelena koreana is indigenous spider in South Korea that lives on piles of trees building webs. RNA-sequencing was performed for venom gland tissue and whole body except venom gland.
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.
Project description:Entomopathogenic nematodes (EPNs) are unique parasitic nematodes due to their symbiosis with entomopathogenic bacteria and their ability to kill insect hosts quickly after infection. Although it has been widely believed that EPNs rely on their bacterial partners for killing insect hosts, compelling evidence from previous studies challenges this model. We developed an improved method of activating millions of Steinernema carpocapsae infective juveniles (IJs) in vitro to harvest excreted/secreted (ES) proteins for bioactivity tests and proteomics analysis. We found that a low dose of the ES proteins from early activated nematodes is lethal to Drosophila melanogaster adults within 2-6 hours. We analyzed the protein composition of this venom using mass spectrometry and identified 472 proteins. Many of these venom proteins share high homology with those of vertebrate-parasitic nematodes. Among many different families of proteins found in the venom, proteases and protease inhibitors are especially abundant. Some toxin-related proteins such as Shk domain-containing proteins were also detected. We further analyzed the transcriptomes of individual non-activated IJs and nematodes that were activated in vitro and in vivo, which revealed a dramatic shift in gene expression during IJ activation. By comparing the whole transcriptomes and the genes encoding venom proteins between the in vitro and in vivo activated nematodes, we confirmed that the in vitro activation is a good approximation of the in vivo process. In summary, our findings strongly support a new model that S. carpocapsae and likely other Steinernema EPNs have a more active role in contributing to the pathogenicity of the nematode-bacterium complex than simply relying on their symbiotic bacteria. Furthermore, we propose that EPNs are a good model system for investigating vertebrate- and human-parasitic nematodes, especially regarding the function of ES products.