Gastric mechanosensation and the peptidergic sugar sensing regulate the Drosophila nutrient sensor
Authors: Yangkyun Oh 1; Jason Lai 1; Soohong Min 2; Huai-Wei Huang 1; Stephen Liberles 2; Hyung Don Ryoo 1; Greg Suh 1,3
Affiliations: 1) Department of Cell Biology, NYU Grossman School of Medicine, New York, NY 10016; 2) Harvard Medical School, Howard Hugh Medical Institute, Department of Cell Biology, Boston, MA 02115; 3) Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
Keywords: k. feeding behavior; k. feeding behavior
Nutrient sensors allow animals to identify foods rich in specific nutrients. The Drosophila nutrient sensor, DH44 neurons, helps the fly to detect nutritive sugar. This sensor becomes operational during starvation; however, the mechanisms by which DH44 neurons or other nutrient sensors are regulated remain unclear. Here, we identified two satiety signals that inhibit DH44 neurons: 1) Piezo-mediated stomach/crop stretch after food ingestion; 2) Neuromedin/Hugin neurosecretory neurons in the ventral nerve cord (VNC) activated by an increase in the internal glucose levels. A subset of Piezo+ neurons that express DH44 neuropeptide project to the crop. We found that DH44 neuronal activity and food intake were stimulated following a knockdown of piezo in DH44 neurons or silencing of the VNC Hugin neurons, even in fed flies. Together, we propose that these two qualitatively distinct peripheral signals work in concert to regulate the DH44 nutrient sensor during the fed state.