Talk by Prof. Michael Pankratz, LIMES Institute, Bonn University
Serotonergic modulation of a feeding circuit along the brain-body axis: Insights from a whole animal EM reconstruction of the enteric nervous system in Drosophila
- Date: Jan 19, 2023
- Time: 02:00 PM - 03:00 PM (Local Time Germany)
- Speaker: Michael Pankratz, Prof. Dr. rer. nat.
- Molecular Brain Physiology and Behavior Lab, LIMES Institute, Universität Bonn
- Location: MPI for Metabolism Research, Gleueler Strasse 50, 50931 Köln
- Room: Seminar room 1
- Host: Prof. Jens Brüning
- Contact: firstname.lastname@example.org
Serotonin has wide-ranging effects on many physiological activities, from feeding and gut motility to mood and motor learning. However, the identity of central serotonergic neurons and the neuronal circuits within which they are embedded are largely unknown at single cell and synaptic level. We have used a scanning transmission electron microscopy dataset of a whole Drosophila larva to elucidate the central sensory-motor circuit that controls swallowing and its coordination with the enteric nervous system. The circuit is composed of Piezo-expressing mechanosensory neurons arrayed along the esophagus which are able to sense the passage of food. Their afferent signal is conveyed onto a set of central serotonergic neurons that project back out via the larval vagus nerve and facilitates swallowing motor pattern. Serotonin release by these neurons modulates serotonin receptor-expressing motor neurons that innervate the muscles underlying esophageal peristalsis. These motor neurons also share an efferent copy of their motor activity with the Piezo neurons sensing food passage. Our analysis reveals an elemental circuit architecture through which successful completion of a rewarding motor task provides a reinforcing and stabilizing signal to the CNS for facilitation of motor learning.