title: Food experience-induced taste desensitization modulated by the Drosophila TRPL channel.
abstract: Animals tend to reject bitter foods. However, long-term exposure to some unpalatable tastants increases acceptance of these foods. Here we show that dietary exposure to an unappealing but safe additive, camphor, caused the fruit fly Drosophila melanogaster to decrease camphor rejection. The transient receptor potential-like (TRPL) cation channel was a direct target for camphor in gustatory receptor neurons, and long-term feeding on a camphor diet led to reversible downregulation of TRPL protein concentrations. The turnover of TRPL was controlled by an E3 ubiquitin ligase, Ube3a. The decline in TRPL levels and increased acceptance of camphor reversed after returning the flies to a camphor-free diet long term. We propose that dynamic regulation of taste receptors by ubiquitin-mediated protein degradation comprises an important molecular mechanism that allows an animal to alter its taste behavior in response to a changing food environment.
authors.affiliation: Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Yali V
authors.initials: YV
authors.lastname: Zhang
authors.forename: Rakesh P
authors.initials: RP
authors.lastname: Raghuwanshi
authors.forename: Wei L
authors.initials: WL
authors.lastname: Shen
authors.forename: Craig
authors.initials: C
authors.lastname: Montell
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001362:Avoidance Learning / Q000502:physiology; D002164:Camphor / Q000494:pharmacology; D002755:Choice Behavior / Q000502:physiology*; D015536:Down-Regulation; D029721:Drosophila Proteins / Q000037:antagonists & inhibitors* / Q000502:physiology*; D004331:Drosophila melanogaster; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D013649:Taste / Q000187:drug effects / Q000502:physiology*; D050051:Transient Receptor Potential Channels / Q000037:antagonists & inhibitors* / Q000502:physiology*
chemical_list: D029721:Drosophila Proteins; D050051:Transient Receptor Potential Channels; C074192:trpl protein, Drosophila; D002164:Camphor