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Meeting Abstract
Parasites with complex life cycles have developed numerous phenotypic strategies that follow a timeline of developmental events and enable the exploitation of different ecological niches. How these environmental shifts are regulated from a metabolic and physiological standpoint still remain to be fully explained. We examined the transcriptomic response of Schistocephalus solidus, a parasite with a complex life cycle, over the course of its development in its intermediate host, the threespine stickleback, and its final avian host. Results from our differential gene expression analysis show major reprogramming events among developmental stages. The final host stage is characterized by a strong activation of reproductive pathways and redox homeostasis. Reaching the infective stage inside the intermediate fish host that precedes sexual maturation in the final host is marked by transcription of genes involved in neural pathways and sensory perception. Our results suggest that un-annotated and S. solidus-specific genes could play a determinant role in host-parasite molecular interactions required to complete the parasitic life cycle. Comparative analyses based on such knowledge will help disentangle species-specific patterns of infections from conserved mechanisms, ultimately leading to a better understanding of the evolution of complex life cycles.