We are working on a better understanding of the function of the nervous system in the holobiont Hydra, which is among the first metazoans that contain neurons. We discovered that the nervous system, with its rich repertoire of neuropeptides, is involved in controlling resident xbeneficial microbes and that microbes affect the animal’s behavior by directly interfering with neuronal receptors. These findings provide new insight into the original role of the nervous system, and suggest that it emerged to orchestrate multiple functions including host-microbiome interactions.
Our current research is focused on uncovering the common rules and principles that govern the interaction between neurons and microbes and the extent to which such laws might apply to other and more complex organisms. Current projects include approaches towards understanding:
- Do microbes play a role in Hydra´s early embryonic development? And more specifically, do resident microbiota influence neurogenesis in embryos and/or in adults? Is the resident microbiota involved in educating neuronal precursor cells/stem cells which, in turn, influence the composition of the microbiota? (Project C1 in CRC 1182)
- What are the fundamental principles underlying growth and formation of the nerve net when developing Hydra embryos/hatchlings are exposed to different environmental stimuli? What are the minimal requirements for neuronal circuits for processing sensory information? Answering these questions will contribute to the understanding of the essential components of an ancestral and functional neuronal circuit and provide conceptual insights into the complexity of neural circuit growth with regard to sensory information processing (proposed project A1 in CRC 1461).
- “One of the greatest accomplishments in the evolution of development is behaviour” (John Tyler Bonner in “The evolution of complexity”, 1988). We are interested in understanding how the high degree of complexity in a large central nervous system works in any profound way. Is the general trend towards more complex and flexible behavior up the evolutionary scale from Hydra to man strictly correlated with the number of neurons?