title: A single identified glomerulus in the zebrafish olfactory bulb carries the high-affinity response to death-associated odor cadaverine.
abstract: The death-associated odor cadaverine, generated by bacteria-mediated decarboxylation of lysine, has been described as the principal activator of a particular olfactory receptor in zebrafish, TAAR13c. Low concentrations of cadaverine activated mainly TAAR13c-expressing olfactory sensory neurons, suggesting TAAR13c as an important element of the neuronal processing pathway linking cadaverine stimulation to a strongly aversive innate behavioral response. Here, we characterized the initial steps of this neuronal pathway. First we identified TAAR13c-expressing cells as ciliated neurons, equivalent to the situation for mammalian taar genes, which shows a high degree of conservation despite the large evolutionary distance between teleost fishes and mammals. Next we identified the target area of cadaverine-responsive OSNs in the olfactory bulb. We report that cadaverine dose-dependently activates a group of dorsolateral glomeruli, at the lowest concentration down to a single invariant glomerulus, situated at the medial border of the dorsolateral cluster. This is the first demonstration of a single stereotyped target glomerulus in the fish olfactory system for a non-pheromone odor. A mix of different amines activates many glomeruli within the same dorsolateral cluster, suggesting this area to function as a general amine response region.
authors.affiliation: Institute of Genetics, Biocenter, University at Cologne, Cologne, Germany.
authors.forename: Milan
authors.initials: M
authors.lastname: Dieris
authors.affiliation: Institute of Genetics, Biocenter, University at Cologne, Cologne, Germany.
authors.forename: Gaurav
authors.initials: G
authors.lastname: Ahuja
authors.affiliation: Institute of Genetics, Biocenter, University at Cologne, Cologne, Germany.
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Krishna
authors.affiliation: Institute of Genetics, Biocenter, University at Cologne, Cologne, Germany.
authors.forename: Sigrun I
authors.initials: SI
authors.lastname: Korsching
mesh_terms: D000818:Animals; D002103:Cadaverine / Q000494:pharmacology*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D007150:Immunohistochemistry; D008856:Microscopy, Fluorescence; D009812:Odorants / Q000032:analysis; D009830:Olfactory Bulb / Q000378:metabolism* / Q000473:pathology; D018034:Olfactory Receptor Neurons / Q000187:drug effects* / Q000378:metabolism; D018035:Receptors, Odorant / Q000378:metabolism*; D015027:Zebrafish / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000378:metabolism*
chemical_list: D018035:Receptors, Odorant; D029961:Zebrafish Proteins; C000627750:taar13c protein, zebrafish; D048049:Extracellular Signal-Regulated MAP Kinases; D002103:Cadaverine