title: Multimodal stimulus coding by a gustatory sensory neuron in Drosophila larvae.
abstract: Accurate perception of taste information is crucial for animal survival. In adult Drosophila, gustatory receptor neurons (GRNs) perceive chemical stimuli of one specific gustatory modality associated with a stereotyped behavioural response, such as aversion or attraction. We show that GRNs of Drosophila larvae employ a surprisingly different mode of gustatory information coding. Using a novel method for calcium imaging in the larval gustatory system, we identify a multimodal GRN that responds to chemicals of different taste modalities with opposing valence, such as sweet sucrose and bitter denatonium, reliant on different sensory receptors. This multimodal neuron is essential for bitter compound avoidance, and its artificial activation is sufficient to mediate aversion. However, the neuron is also essential for the integration of taste blends. Our findings support a model for taste coding in larvae, in which distinct receptor proteins mediate different responses within the same, multimodal GRN.
authors: Department of Biology, Institute of Zoology, University of Fribourg, Chemin du Musee 10, Fribourg CH-1700, Switzerland.
authors: Lena
authors: L
authors: van Giesen
authors: Center for Brain Science and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Luis
authors: http://orcid.org/0000-0003-3102-9036
authors: L
authors: Hernandez-Nunez
authors: Microsystems Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland.
authors: Sophie
authors: S
authors: Delasoie-Baranek
authors: Faculty of Biology and Medicine, Center for Integrative Genomics, University of Lausanne, Genopode Building, Lausanne CH-1015, Switzerland.
authors: Martino
authors: M
authors: Colombo
authors: Microsystems Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne CH-1015, Switzerland.
authors: Philippe
authors: P
authors: Renaud
authors: Faculty of Biology and Medicine, Center for Integrative Genomics, University of Lausanne, Genopode Building, Lausanne CH-1015, Switzerland.
authors: Rémy
authors: R
authors: Bruggmann
authors: Interfaculty Bioinformatics Unit and Swiss Institute of Bioinformatics, University of Berne, Berne 3012, Switzerland.
authors: Richard
authors: R
authors: Benton
authors: Center for Brain Science and Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
authors: Aravinthan D T
authors: ADT
authors: Samuel
authors: Department of Biology, Institute of Zoology, University of Fribourg, Chemin du Musee 10, Fribourg CH-1700, Switzerland.
authors: Simon G
authors: SG
authors: Sprecher
mesh_terms: D000818:Animals; D002755:Choice Behavior; D029721:Drosophila Proteins / Q000235:genetics; D004331:Drosophila melanogaster; D005455:Fluorescent Antibody Technique; D007814:Larva / Q000502:physiology*; D010812:Physical Stimulation; D000644:Quaternary Ammonium Compounds; D011956:Receptors, Cell Surface / Q000235:genetics; D011984:Sensory Receptor Cells / Q000502:physiology; D013395:Sucrose; D013649:Taste / Q000502:physiology*; D013650:Taste Buds / Q000502:physiology*
chemical_list: D029721:Drosophila Proteins; C516369:Gr21a protein, Drosophila; C579546:Gr66a protein, Drosophila; D000644:Quaternary Ammonium Compounds; D011956:Receptors, Cell Surface; C405956:gustatory receptor, Drosophila; D013395:Sucrose