Biologists and chemists from the Department of Natural Sciences at Western New Mexico University will collaborate on an investigation of the molecular interactions between predatory spider wasps (family Pompilidae) and the spiders they sting and paralyze to use as living food provisions for their own parasitic larvae. Beyond gathering data that will describe the biology and evolutionary history of this particular system, the project also addresses key questions about molecular adaptation, the molecular physiology of predator/prey and parasite/host interactions, and the mechanisms that help generate biodiversity - such as antagonistic coevolution. About 200 species of spider wasps are known to occur in the United States. The venoms of these solitary insects are known to be relatively simple, consisting mainly of short peptides such as pompilidotoxins (PMTXs). PMTXs are neurotoxins that bind to a known site on voltage-gated sodium channel proteins, inhibiting their inactivation and disrupting the functions of the nervous system. This project will characterize venom peptides from a diverse sample of spider wasps using mass spectrometry and venom gland transcriptome sequencing; and examine the DNA sequence diversity of targeted spider sodium channels, particularly at sites critical for PMTX binding. Since survival and reproduction of spider wasps depends on the potency of their venoms, while survival and reproduction of targeted spiders depends on their genetic sensitivity (or possible resistance) to the toxins, this project will also use phylogenetic trees of species relationships to describe the evolutionary histories of these molecules and their interactions, which are likely to evolve via natural selection.
Animal neurotoxins are of broad interest due to their potential medical value in treating human health conditions including pain, epilepsy, stroke, and some cardiovascular disorders. Additionally, seminal discoveries in neuroscience emerged from structure/function studies of nervous system proteins such as sodium channels, and how they are affected by natural neurotoxins. For the grantee institution, this project will enhance research infrastructure via partial funding for shared-use molecular biology instrumentation and provide new opportunities for undergraduate participants to gain experience and training in research techniques used in molecular biology and analytical chemistry. Data generated by the project will be deposited into public databases including NCBI/GenBank, UniProt, and PRIDE (EMBL-EBI). Voucher specimens used in the characterizations of wasp venoms and spider sodium channels will be deposited into the permanent collections of the Gila Center for Natural History at Western New Mexico University in Silver City, NM.
