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Title: Taste cells expressing Ionotropic Receptor 94e reciprocally impact feeding and egg laying in Drosophila
Chemosensory cells across the body of Drosophila melanogaster evaluate the environment to prioritize certain behaviors. Previous mapping of gustatory receptor neurons (GRNs) on the fly labellum identified a set of neurons in L-type sensilla that express Ionotropic Receptor 94e (IR94e), but the impact of IR94e GRNs on behavior remains unclear. We used optogenetics and chemogenetics to activate IR94e neurons and found that they drive mild feeding suppression but enhance egg laying. In vivo calcium imaging revealed that IR94e GRNs respond strongly to certain amino acids, including glutamate, and that IR94e plus co-recep- tors IR25a and IR76b are required for amino acid detection. Furthermore, IR94e mutants show behavioral changes to solutions containing amino acids, including increased consumption and decreased egg laying. Overall, our results suggest that IR94e GRNs on the fly labellum discourage feeding and encourage egg laying as part of an important behavioral switch in response to certain chemical cues.  more » « less
Award ID(s):
2332375
PAR ID:
10569851
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Cell Press
Date Published:
Journal Name:
Cell Reports
Volume:
43
Issue:
8
ISSN:
2211-1247
Page Range / eLocation ID:
114625
Subject(s) / Keyword(s):
Neuroscience Drosophila melanogaster IR94e amino acids chemosensation egg laying feeding behavior glutamate gustation ionotropic receptor oviposition
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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