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:Orb-weaving spiders use a highly strong, sticky and elastic web to catch their prey. These web properties alone would be enough for the entrapment of prey; however, these spiders may be hiding venomous secrets in the web, which current research is revealing. Here, we provide strong proteotranscriptomic evidence for the presence of toxin/neurotoxin-like proteins, defensins and proteolytic enzymes on the web silk from Nephila clavipes spider. The results from quantitative-based transcriptomics and proteomic approaches showed that silk-producing glands produce an extensive repertoire of toxin/neurotoxin-like proteins, similar to those already reported in spider venoms. Meanwhile, the insect toxicity results demonstrated that these toxic components can be lethal and/or paralytic chemical weapons used for prey capture on the web; and the presence of fatty acids in the web may be responsible mechanism for open the way to the web-toxins for accessing the interior of prey's body, as showed here. Comparative phylogenomic-level evolutionary analyses revealed orthologous genes among two spider groups - Araneomorphae and Mygalomorphae; and the findings showed protein sequences similar to toxins found in the taxa Scorpiones and Hymenoptera in addition to Araneae. Overall, these data represent a valuable resource to further investigate other spider web toxin systems; these data also suggest that N. clavipes web is not a passive mechanical trap for prey capture, but it exerts an active role in prey paralysis/killing using a series of neurotoxins.
Project description:Spiders are a highly diverse group of arthropods that occur in most habitats on land. Notably, spiders have significant ecological impact as predators because of their extraordinary prey capture adaptations, venom and silk. Spider venom is among the most heterogeneous animal venoms and has pharmacological applications, while spider silk is characterized by great toughness with potential for biomaterial application. We describe the genome sequences of two spiders representing two major taxonomic groups, the social velvet spider Stegodyphus mimosarum (Araneomorphae), and the Brazilian white-knee tarantula Acanthoscurria geniculata (Mygalomorphae). We annotate genes using a combination of transcriptomic and in-depth proteomic analyses. The genomes are large (2.6 Gb and 6 Gb, respectively) with short exons and long introns and approximately 50% repeats, reminiscent of typical mammalian genomes. Phylogenetic analyses show that spiders and ticks are sister groups outgrouped by mites, and phylogenetic dating using a molecular clock dates separation of velvet spider and tarantula at 270 my. Based on the genomes and proteomes, we characterize the genetic basis of venom and silk production of both species in detail. Venom protein composition differs markedly between the two spiders, with lipases as the most abundant protein in the velvet spider and present only at low concentration in tarantula. Venom in both spiders contains proteolytic enzymes, and our analyses suggest that these enzymes target and process precursor peptides that subsequently mediate the toxic effects of venom. Complete analysis of silk genes reveal a diverse suite of silk proteins in the velvet spider including novel types of spidroins, and dynamic evolution of major ampullate spidroin genes, whereas silk protein diversity in tarantula is far less complex. The difference in silk proteins between species is consistent with a more complex silk gland morpholgy and use of three-dimentional capture webs consisting of multiple silk types in aranomorph spiders.
Project description:Spider venoms are a unique source of bioactive peptides displaying remarkable structural stability and potent neuroactivity. Phoneutria nigriventer, often referred to as Brazilian wandering spider, banana spider or “armed” spider, is endemic from South America and amongst the most dangerous venomous spiders in the world. Envenomation accidents with P. nigriventer often occur in Brazil with approximately 4,000 cases per year and which symptoms include priapism, hypertension, blurred vision, sweating, and vomiting, amongst others. Besides its clinical relevance, P. nigriventer venom comprises promising peptide drug leads providing therapeutic effects in a range of disease models. In this study, we further explored the neuroactivity and molecular diversity of the venom from P. nigriventer using fractionation-guided high-throughput cellular assays coupled to proteomics analysis and multi-pharmacology activity to broaden the knowledge and therapeutic potential of this venom, as well as a proof-of-concept for an investigative pipeline to study spider-venom derived neuroactive peptides. We applied ion channel assays in a neuroblastoma cell line to investigate modulation of voltage-gated sodium and calcium channels, and nicotinic acetylcholine α7 receptor. We then investigated the venom components using mass spectrometry to identify peptide masses and sequences associated to the observed neuromodulations. Our findings showed this venom is highly complex compared to other neurotoxin-rich venoms and comprises potent modulators of voltage-gated sodium and calcium channels which were classified into 4 families of neuroactive peptides based on their activities and structures. In addition to the reported P. nigriventer neuroactive peptides, we identified at least 27 novel cysteine-rich venom peptides in which neuroactivities are still to be elucidated in voltage-gated ion channels and other potential targets. Our findings provide a new basis for studying non-explored bioactivities of known and novel neuroactive components in P. nigriventer venom, and further supports the successful application of our discovery pipeline for identifying ion channel-targeting venom peptides with potential to become drug leads with diverse exploratory and therapeutic applications.
Project description:The spider venom-derived peptide GsMTx4 specifically inhibits mechanosensory ion channels. It has been reported that GsMTx4 plays an immunoregulatory role in several inflammatory conditions. Therefore, we administrated GsMTx4 to mice with dextran sodium sulfate (DSS)-induced acute colitis, to explore whether it regulates inflammatory responses in colitis.