Investigating the composition, exochemistry, and variation of Macrovipera schweizeri venom across the Milos archipelago (MacroVen)

• Applicants: Ignazio Avella, Ph.D.; Tim Lueddecke, Ph.D.
• Subject Area: Animal Physiology and Biochemistry ; Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 545040837

Animal venoms, characterized by complex mixtures of bioactive compounds, have evolved independently across various taxa for prey subjugation, defense, and intraspecific interactions. Traditional venom research has evolved over the last two decades with the incorporation of high-throughput “omic” technologies, such as proteomics, transcriptomics, and genomics. This has led to the birth of the so-called “venomics”, allowing a comprehensive study of an organism’s whole venom profile. Snake venom, a rapidly evolving functional trait, serves primarily for prey subjugation, and its composition varies significantly between species, genera, and even between and within populations of the same species. The genetic basis of snake venom variation is complex, ranging from strict genotype-phenotype links to selective translation from similar genomes. Such variability poses challenges for snakebite treatment, as antivenoms may fail due to differences in venom composition. Despite the importance of understanding intraspecific venom variation for both primary venom research and snakebite management, this phenomenon has only recently gained attention. The Milos viper, Macrovipera schweizeri, is proposed as an ideal model for studying venom variation due to its unique distribution, exclusively comprising the four islands of the Milos archipelago in Greece, and specific ecological features. The proposed two-year project aims to explore the composition, biochemistry, and intraspecific variation of M. schweizeri venom between and within the islands composing this species’ distribution range. This requires extensive fieldwork, proteomic analyses, bioassays, and whole-genome sequencing. The fieldwork will involve the collection of biometric data, venom, and tissue samples from M. schweizeri from distinct populations within the Milos archipelago, sampling vipers of different sexes and age classes. The proteomic analysis will utilize advanced mass spectrometry techniques to assess venom variation at different levels. Bioassays will then be employed to evaluate the functional consequences of venom variation, including cytotoxicity, protease activity, and impact on blood clotting. To understand the genetic basis of venom variation, medium-coverage whole-genome sequencing will be performed on specimens from different populations. The proposed project benefits from the applicants' expertise, a robust network of international collaborations, and a strong foundation in venom research, positioning it to contribute significantly to the understanding of the dynamic processes governing venom phenotypes in the Milos viper.

• DFG Programme: Research Grants