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Title: Feeding state sculpts a circuit for sensory valence in Caenorhabditis elegans

Hunger affects the behavioral choices of all animals, and many chemosensory stimuli can be either attractive or repulsive depending on an animal’s hunger state. Although hunger-induced behavioral changes are well documented, the molecular and cellular mechanisms by which hunger modulates neural circuit function to generate changes in chemosensory valence are poorly understood. Here, we use the CO2response of the free-living nematodeCaenorhabditis elegansto elucidate how hunger alters valence. We show that CO2response valence shifts from aversion to attraction during starvation, a change that is mediated by two pairs of interneurons in the CO2circuit, AIY and RIG. The transition from aversion to attraction is regulated by biogenic amine signaling. Dopamine promotes CO2repulsion in well-fed animals, whereas octopamine promotes CO2attraction in starved animals. Biogenic amines also regulate the temporal dynamics of the shift from aversion to attraction such that animals lacking octopamine show a delayed shift to attraction. Biogenic amine signaling regulates CO2response valence by modulating the CO2-evoked activity of AIY and RIG. Our results illuminate a new role for biogenic amine signaling in regulating chemosensory valence as a function of hunger state.

 
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NSF-PAR ID:
10083453
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
116
Issue:
5
ISSN:
0027-8424
Page Range / eLocation ID:
p. 1776-1781
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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