title: The full repertoire of Drosophila gustatory receptors for detecting an aversive compound.
abstract: The ability to detect toxic compounds in foods is essential for animal survival. However, the minimal subunit composition of gustatory receptors required for sensing aversive chemicals in Drosophila is unknown. Here we report that three gustatory receptors, GR8a, GR66a and GR98b function together in the detection of L-canavanine, a plant-derived insecticide. Ectopic co-expression of Gr8a and Gr98b in Gr66a-expressing, bitter-sensing gustatory receptor neurons (GRNs) confers responsiveness to L-canavanine. Furthermore, misexpression of all three Grs enables salt- or sweet-sensing GRNs to respond to L-canavanine. Introduction of these Grs in sweet-sensing GRNs switches L-canavanine from an aversive to an attractive compound. Co-expression of GR8a, GR66a and GR98b in Drosophila S2 cells induces an L-canavanine-activated nonselective cation conductance. We conclude that three GRs collaborate to produce a functional L-canavanine receptor. Thus, our results clarify the full set of GRs underlying the detection of a toxic tastant that drives avoidance behaviour in an insect.
authors.affiliation: Department of Oral Biology, BK21 PLUS Project Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul 120-752, Korea.|Division of Functional Food Research, Korea Food Research Institute, Seongnam, Gyeonggi-do 463-746, Korea.
authors.forename: Jaewon
authors.initials: J
authors.lastname: Shim
authors.affiliation: Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 136-702, Korea.
authors.forename: Youngseok
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Department of Oral Biology, BK21 PLUS Project Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul 120-752, Korea.
authors.forename: Yong Taek
authors.initials: YT
authors.lastname: Jeong
authors.affiliation: Department of Pharmacology, Brain Korea 21 PLUS project for Medical Sciences Yonsei University College of Medicine, Yonsei-ro 50-1, Seodaemun-gu, Seoul 120-752, Korea.
authors.forename: Yonjung
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Pharmacology, Brain Korea 21 PLUS project for Medical Sciences Yonsei University College of Medicine, Yonsei-ro 50-1, Seodaemun-gu, Seoul 120-752, Korea.
authors.forename: Min Goo
authors.initials: MG
authors.lastname: Lee
authors.affiliation: Department of Molecular, Cellular, and Developmental Biology, Neuroscience Research Institute, University of California, Santa Barbara, California 93106, USA.
authors.forename: Craig
authors.initials: C
authors.lastname: Montell
authors.affiliation: Department of Oral Biology, BK21 PLUS Project Yonsei University College of Dentistry, Yonsei-ro 50-1, Seodaemun-gu, Seoul 120-752, Korea.
authors.forename: Seok Jun
authors.identifier: http://orcid.org/0000-0001-7282-2888
authors.initials: SJ
authors.lastname: Moon
mesh_terms: D000818:Animals; D001362:Avoidance Learning; D002172:Canavanine / Q000378:metabolism*; D002628:Chemoreceptor Cells / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster; D007306:Insecticides / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D013650:Taste Buds / Q000378:metabolism*
chemical_list: D029721:Drosophila Proteins; C579546:Gr66a protein, Drosophila; C000607439:Gr8a protein, Drosophila; C000607440:Gr98a protein, Drosophila; D007306:Insecticides; D011956:Receptors, Cell Surface; C405956:gustatory receptor, Drosophila; D002172:Canavanine