TY - JOUR
T1 - Excitatory Local Circuits and Their Implications for Olfactory Processing in the Fly Antennal Lobe
AU - Shang, Yuhua
AU - Claridge-Chang, Adam
AU - Sjulson, Lucas
AU - Pypaert, Marc
AU - Miesenböck, Gero
N1 - Funding Information:
We are grateful to Dylan Clyne for odor-concentration measurements, to Robert Roorda for help with instrumentation, to Kim Zichichi for assistance with immunoelectron microscopy, to Elissa Hallem and John Carlson for sharing unpublished information, to Ajay Srivastava, Tatsushi Igaki, Laura Pedraza, and Tian Xu for access to their confocal microscope, and to Peter Takizawa and Graham Warren for comments on the manuscript. Paul Salvaterra donated antibodies; Douglas Armstrong, John Carlson, Liqun Luo, Reinhard Stocker, Klemens Störtkuhl, Tim Tully, and Leslie Vosshall provided fly strains. This work was supported by a grant from the NIH.
PY - 2007/2/9
Y1 - 2007/2/9
N2 - Conflicting views exist of how circuits of the antennal lobe, the insect equivalent of the olfactory bulb, translate input from olfactory receptor neurons (ORNs) into projection-neuron (PN) output. Synaptic connections between ORNs and PNs are one-to-one, yet PNs are more broadly tuned to odors than ORNs. The basis for this difference in receptive range remains unknown. Analyzing a Drosophila mutant lacking ORN input to one glomerulus, we show that some of the apparent complexity in the antennal lobe's output arises from lateral, interglomerular excitation of PNs. We describe a previously unidentified population of cholinergic local neurons (LNs) with multiglomerular processes. These excitatory LNs respond broadly to odors but exhibit little glomerular specificity in their synaptic output, suggesting that PNs are driven by a combination of glomerulus-specific ORN afferents and diffuse LN excitation. Lateral excitation may boost PN signals and enhance their transmission to third-order neurons in a mechanism akin to stochastic resonance.
AB - Conflicting views exist of how circuits of the antennal lobe, the insect equivalent of the olfactory bulb, translate input from olfactory receptor neurons (ORNs) into projection-neuron (PN) output. Synaptic connections between ORNs and PNs are one-to-one, yet PNs are more broadly tuned to odors than ORNs. The basis for this difference in receptive range remains unknown. Analyzing a Drosophila mutant lacking ORN input to one glomerulus, we show that some of the apparent complexity in the antennal lobe's output arises from lateral, interglomerular excitation of PNs. We describe a previously unidentified population of cholinergic local neurons (LNs) with multiglomerular processes. These excitatory LNs respond broadly to odors but exhibit little glomerular specificity in their synaptic output, suggesting that PNs are driven by a combination of glomerulus-specific ORN afferents and diffuse LN excitation. Lateral excitation may boost PN signals and enhance their transmission to third-order neurons in a mechanism akin to stochastic resonance.
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U2 - 10.1016/j.cell.2006.12.034
DO - 10.1016/j.cell.2006.12.034
M3 - Article
C2 - 17289577
AN - SCOPUS:33846686409
SN - 0092-8674
VL - 128
SP - 601
EP - 612
JO - Cell
JF - Cell
IS - 3
ER -