Acid sensing by the Drosophila olfactory system.

• Published in: Nature
• Main Authors: Ai, Minrong, Min, Soohong, Grosjean, Yael, Leblanc, Charlotte, Bell, Rati, Benton, Richard, Suh, Greg S B
• Other Authors: New York University School of Medicine (NYU), New York University School of Medicine, NYU System (NYU)-NYU System (NYU), Centre des Sciences du Goût et de l'Alimentation Dijon (CSGA), Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS), Center for Integrative Genomics - Institute of Bioinformatics, Génopode (CIG), Swiss Institute of Bioinformatics Lausanne (SIB), Université de Lausanne = University of Lausanne (UNIL)-Université de Lausanne = University of Lausanne (UNIL), Université de Lausanne = University of Lausanne (UNIL)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2010
• Subjects: ANIMAL BEHAVIOUR; NEUROSCIENCE; GENETICS; GENOMICS; MESH: Acetic Acid; MESH: Acids; MESH: Odors; MESH: Olfactory Pathways; MESH: Receptors; Ionotropic Glutamate; Odorant; MESH: Sensilla; MESH: Sensory Receptor Cells; MESH: Temperature; MESH: Animals; MESH: Arthropod Antennae; MESH: Calcium Signaling; MESH: Carbon Dioxide; MESH: Carbonic Acid; MESH: Drosophila Proteins; MESH: Drosophila melanogaster; MESH: Maze Learning; [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition; Carbonic acid
• Online Access: https://hal.science/hal-00755440; https://doi.org/10.1038/nature09537

International audience The odour of acids has a distinct quality that is perceived as sharp, pungent and often irritating. How acidity is sensed and translated into an appropriate behavioural response is poorly understood. Here we describe a functionally segregated population of olfactory sensory neurons in the fruitfly, Drosophila melanogaster, that are highly selective for acidity. These olfactory sensory neurons express IR64a, a member of the recently identified ionotropic receptor (IR) family of putative olfactory receptors. In vivo calcium imaging showed that IR64a+ neurons projecting to the DC4 glomerulus in the antennal lobe are specifically activated by acids. Flies in which the function of IR64a+ neurons or the IR64a gene is disrupted had defects in acid-evoked physiological and behavioural responses, but their responses to non-acidic odorants remained unaffected. Furthermore, artificial stimulation of IR64a+ neurons elicited avoidance responses. Taken together, these results identify cellular and molecular substrates for acid detection in the Drosophila olfactory system and support a labelled-line mode of acidity coding at the periphery.