title: Elucidating the Neuronal Architecture of Olfactory Glomeruli in the Drosophila Antennal Lobe.
abstract: Olfactory glomeruli are morphologically conserved spherical compartments of the olfactory system, distinguishable solely by their chemosensory repertoire, anatomical position, and volume. Little is known, however, about their numerical neuronal composition. We therefore characterized their neuronal architecture and correlated these anatomical features with their functional properties in Drosophila melanogaster. We quantitatively mapped all olfactory sensory neurons (OSNs) innervating each glomerulus, including sexually dimorphic distributions. Our data reveal the impact of OSN number on glomerular dimensions and demonstrate yet unknown sex-specific differences in several glomeruli. Moreover, we quantified uniglomerular projection neurons for each glomerulus, which unraveled a glomerulus-specific numerical innervation. Correlation between morphological features and functional specificity showed that glomeruli innervated by narrowly tuned OSNs seem to possess a larger number of projection neurons and are involved in less lateral processing than glomeruli targeted by broadly tuned OSNs. Our study demonstrates that the neuronal architecture of each glomerulus encoding crucial odors is unique.
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
authors.forename: Veit
authors.initials: V
authors.lastname: Grabe
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
authors.forename: Amelie
authors.initials: A
authors.lastname: Baschwitz
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
authors.forename: Hany K M
authors.initials: HKM
authors.lastname: Dweck
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
authors.forename: Sofia
authors.initials: S
authors.lastname: Lavista-Llanos
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany.
authors.forename: Bill S
authors.initials: BS
authors.lastname: Hansson
authors.affiliation: Department of Evolutionary Neuroethology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Strasse 8, 07745 Jena, Germany. Electronic address: ssachse@ice.mpg.de.
authors.forename: Silke
authors.initials: S
authors.lastname: Sachse
mesh_terms: D000818:Animals; D057506:Arthropod Antennae / Q000294:innervation*; D004331:Drosophila melanogaster; D005260:Female; D008297:Male; D009830:Olfactory Bulb / Q000166:cytology*; D018034:Olfactory Receptor Neurons / Q000166:cytology*
keywords: glomerular volume; lifetime sparseness; odor response profiles; olfactory sensory neurons; projection neurons