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:In order to provide a global insight on the transcripts expressed in the venom gland of the Brazilian ant species Tetramorium bicarinatum and to unveil the potential of its products, high-throughput expressed sequence tags were generated using Illumina paired-end sequencing technology. A total of 212,371,758 pairs of quality-filtered, 100-base-pair Illumina reads were obtained. The de novo assemblies yielded 36,042 contigs for which 27,873 have at least one predicted ORF among which 59.77% produce significant hits in the available databases. The investigation of the reads mapping toxin class revealed a high diversification with the major part consistent with the classical hymenopteran venom protein signature represented by venom allergen (33.3%) followed by a diverse toxin-expression profile including several distinct isoforms of phospholipase A1 and A2, venom serine protease, hyaluronidase, protease inhibitor and secapin. Moreover, our results revealed for the first time the presence of toxin-like peptides that have been previously identified from unrelated venomous animals such as waprin-like (snakes) and agatoxins (spiders and conus). 300 ant specimens from the species Tetramorium bicarinatum were dissected in order to extract the RNA from their venom gland, The whole ant body was used as a reference,
Project description:In the mutualisms involving certain pseudomyrmicine ants and different myrmecophytes (i.e., plants sheltering colonies of specialized “plant-ant” species in hollow structures), the ant venom contributes to the host plant biotic defenses by inducing the rapid paralysis of defoliating insects and causing intense pain to browsing mammals. Using integrated transcriptomic and proteomic approaches, we identified the venom peptidome of the plant-ant Tetraponera aethiops (Pseudomyrmecinae). The transcriptomic analysis of its venom glands revealed that 40 % of the assembled contigs encoded only seven peptide precursors related to the ant venom peptides from the A-superfamily. Among the 12 peptide masses detected by liquid chromatography-mass spectrometry (LC-MS), nine mature peptide sequences were characterized and confirmed through proteomic analysis. These venom peptides, called pseudomyrmecitoxins (PSDTX), share amino acid sequence homologies with myrmeciitoxins known for their dual offensive and defensive functions on both insects and mammals. Furthermore, we demonstrated through reduction/alkylation of the crude venom that four PSDTXs were homo- and heterodimeric. Thus, we provide the first indication that the defensive venom composition of the ant genus Tetraponera is a streamlined peptidome. We provide the first insights into the defensive venom composition of the ant genus Tetraponera indicative of a streamlined peptidome.
Project description:Animal venoms are a rich source of novel biomolecules with tremendous potential in medicine and agriculture. Ants represent one of the most species-rich lineages of venomous animals. However, only a fraction of their biodiversity has been studied so far. Here, we investigated the venom compositions from Myrmica rubra and Myrmica ruginodis, two members of the Myrmicinae subfamily of ants. We applied a proteo-transcriptomics based venomics workflow. Our analysis revealed that venoms of both species are composed of several protein classes, such as venom serine protease, cysteine-rich secretory proteins, antigen 5 and pathogenesis-related 1 proteins (CAP), Kunitz-type serine protease inhibitors or venom acid phosphatase. Several protein classes identified are known venom allergens, and for the first time we detected phospholipase A1 in the venom of M. ruginodis. We also identified two novel toxins of the epidermal growth factor (EGF) family in its venom proteome and an array of additional EGF-like toxins in venom gland transcriptomes of both species. They display similarity to known toxins from the related myrmecine Manica rubida and the Australian red bulldog ant Myrmecia gullosa of the Myrmeciinae subfamily and may serve as nociceptive weapons in defensive scenarios. Our work suggests that the venoms of M. rubra and M. ruginodis contain many high molecular proteins and enzymes with putatively cell damaging functions. Nevertheless, the presence of EGF-like toxins underpins that myrmicine ants also recruited smaller peptide components into their venom arsenal. Although little is known about the bioactivity and function of these EGF-like toxins, their presence in Myrmecinae and Myrmeciinae suggests that they play an important role for the venom systems of Formicoidea. Our work adds to the emerging picture of ant venoms as a source for novel biomolecules. This underlines the importance to incorporate such taxa in future venom bioprospecting programs.
Project description:In order to provide a global insight on the transcripts expressed in the venom gland of the Brazilian ant species Tetramorium bicarinatum and to unveil the potential of its products, high-throughput expressed sequence tags were generated using Illumina paired-end sequencing technology. A total of 212,371,758 pairs of quality-filtered, 100-base-pair Illumina reads were obtained. The de novo assemblies yielded 36,042 contigs for which 27,873 have at least one predicted ORF among which 59.77% produce significant hits in the available databases. The investigation of the reads mapping toxin class revealed a high diversification with the major part consistent with the classical hymenopteran venom protein signature represented by venom allergen (33.3%) followed by a diverse toxin-expression profile including several distinct isoforms of phospholipase A1 and A2, venom serine protease, hyaluronidase, protease inhibitor and secapin. Moreover, our results revealed for the first time the presence of toxin-like peptides that have been previously identified from unrelated venomous animals such as waprin-like (snakes) and agatoxins (spiders and conus).
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: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.