Project description:Venoms and the toxins they contain represent molecular adaptations that have evolved on numerous occasions throughout the animal kingdom. However, the processes that shape venom protein evolution are poorly understood because of the scarcity of whole genome data available for comparative analyses of venomous species. Here, we perform a broad comparative toxicogenomic analysis to gain insight into the genomic mechanisms of venom evolution in robber flies (Asilidae). We first sequenced a high-quality draft genome of the hymenopteran hunting robber fly Dasypogon diadema, and analysed its venom by a combined proteotranscriptomic approach, and compared our results to recently described robber fly venoms to assess the general composition and major components of asilid venom. We then applied a comparative genomics approach, based on one additional asilid genome, ten high-quality dipteran genomes, and two lepidopteran outgroup-genomes, to reveal the evolutionary mechanisms and origins of identified venom proteins in robber flies. While some venom proteins were identified in the non-asilid genomes, several of the identified highly expressed venom proteins appear to be unique to robber flies. Our results reveal that the venom of D. diadema likely evolves in a multimodal fashion comprising 1) neofunctionalization after gene duplication, 2) expression-dependent co-option of proteins and 3) asilid lineage-specific orphan genes with enigmatic origin. The role of such orphan genes is currently being disputed in evolutionary genomics, but has not yet discussed in the context of toxin evolution. Our results display an unexpected dynamic venom evolution in asilid insects, which contrasts the findings of the only other insect toxicogenomic evolutionary analysis, in parasitoid wasps (Hymenoptera), were toxin evolution is dominated by single gene co-option.
2019-06-13 | PXD013358 | Pride
Project description:Ultraconserved elements help resolve the phylogeny of an ancient radiation of venomous flies (Insecta: Diptera: Asilidae)
Project description:Health risks caused by stings from Vespa velutina nigrithorax (VV), also known as the yellow-legged Asian hornet, have become a public concern, but little is known about its venom composition. This study presents the proteome profile of the VV’s venom sac based on Sequential Window Acquisition of all Theoretical Mass Spectra (SWATH-MS). The study also performed proteomic quantitative analysis and examined the biological pathways and molecular functions of the proteins in the VS of VV gynes (i.e., future queens [SQ]) and workers [SW]). The total protein content per VS was significantly higher in the SW than in the SQ (274 ± 54 µg/sac vs. 175 ± 22 µg/sac; p=0.02). We quantified a total of 228 proteins belonging to 7 different classes: Insecta (n=191); Amphibia and Reptilia (n=20); Bacilli, γ-Proteobacteria and Pisoniviricetes (n=12); and Arachnida (n=5). Phage proteins of Paenibacillus larvae, the etiological agent of American foulbrood, and genome polyprotein from deformed wing virus were quantified by SWATH-MS. Among the 228 identified proteins, 66 showed significant differential expression between SQ and SW. The well-known allergens hyaluronidase A, venom antigen 5 and phospholipase A1 were significantly downregulated in the SQ venom.
2023-05-10 | PXD040764 | Pride
Project description:Whole-genome sequencing of Culicidae (Insecta: Diptera)
Project description:Proteomic analysis of Tityus obscurus venom identified 45 proteins, including novel ion channel-targeting peptides with potential pharmacological relevance. These findings enhance our understanding of venom diversity and evolution, offering insights into peptide structure-function relationships for drug development.
Project description:Mucuna pruriens extract MPE pretreatment may have a direct protective effect on heart (other than immunological neutralization of the venom neurotoxin and phospholipase A2 by the anti-MPE antibodies) that renders the heart more resistant to the toxic action of the venom The direct protective effect probably involves functional changes to the cardiac tissue that enable the heart to resist the reduction of contractility and rate induced by the cobra venom.To explore the possibility of the direct action of MPE pretreatment on heart and to understand the molecular events involved in the protection of MPE pretreatment against the lethal action of Naja sputatrix venom, gene expression studies were carried out using microarray analysis. Rats were divided into four groups (n=6): negative control (abbreviated as ‘negative’ group), MPE pretreated group (abbreviated as ‘MPE’ group), N. sputatrix venom-challenge group (abbreviated as ‘NS’ group) and N. sputatrix venom-challenge to MPE pretreated animals group (abbreviated as ‘MPE-NS’ group). In the ‘MPE’ group, rats were injected with MPE at a dose of 21 mg/kg (i.p.), on day 0, 7 and 14, and sacrificed on day 21. In the ‘negative’ group (the untreated, control group), rats were injected with saline of the same volume and sacrificed also on day 21. Hearts were then harvested immediately. In the N. sputatrix venom-challenge group (‘NS’ group), untreated rats were challenged with 1.5 LD50 (1.25 ?g/g) of N. sputatrix venom whereas in the venom challenge to MPE pretreated animals group (the ‘MPE-NS’ group), MPE pretreated rats were challenged with 1.5 LD50 (1.25 ?g/g) of N. sputatrix venom, both on day 21. For the ‘NS’ and ‘MPE-NS’ group, the rats were observed for 24 h after venom challenged and hearts were harvested as soon as death occurred or 24 h after the venom injection, whichever occurred first.
Project description:We generated ATAC-seq data for pre- and post-extraction venom gland samples and H3K4me3, H3K27ac, and CTCF ChIP-seq from post-extraction venom gland samples from the Prairie Rattlesnake to investigate patterns of chromatin accessibility, transcription factor binding, and insulation during venom production, and to identify open promoters and active enhancer regions.