Satiety controls behavior in Hydra through an interplay of pre-enteric and central nervous system-like neuron populations
Christoph Giez,
Christopher Noack,
Ehsan Sakib,
Lisa-Marie Hofacker,
Urska Repnik,
Marc Bramkamp,
Thomas C.G. Bosch
Affiliations
Christoph Giez
Zoological Institute, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany; Neural Circuits and Evolution Laboratory, Francis Crick Institute, London NW1 1AT, UK; Corresponding author
Christopher Noack
Zoological Institute, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
Ehsan Sakib
Zoological Institute, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
Lisa-Marie Hofacker
Zoological Institute, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
Urska Repnik
Centrale Microscopy, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
Marc Bramkamp
Centrale Microscopy, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany; Institute for General Microbiology, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany
Thomas C.G. Bosch
Zoological Institute, University of Kiel, Am Botanischen Garten 1-9, 24118 Kiel, Germany; Corresponding author
Summary: Hunger and satiety can have an influence on decision-making, sensory processing, and motor behavior by altering the internal state of the brain. This process necessitates the integration of peripheral sensory stimuli into the central nervous system. Here, we show how animals without a central nervous system such as the cnidarian Hydra measure and integrate satiety into neuronal circuits and which specific neuronal populations are involved. We demonstrate that this simple nervous system, previously referred to as diffuse, has an endodermal subpopulation (N4) similar to the enteric nervous system (feeding-associated behavior) and an ectodermal population (N3) that performs central nervous system-like functions (physiology/motor). This view of a supposedly simple nervous system could open an important window into the origin of more complex nervous systems.
