Propagation of olfactory information in Drosophila
- 10 July 2007
- journal article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences of the United States of America
- Vol. 104 (28), 11826-11831
- https://doi.org/10.1073/pnas.0704523104
Abstract
Investigating how information propagates between layers in the olfactory system is an important step toward understanding the olfactory code. Each glomerular output projection neuron (PN) receives two sources of input: the olfactory receptor neurons (ORNs) of the same glomerulus and interneurons that innervate many glomeruli. We therefore asked how these inputs interact to produce PN output. We used receptor gene mutations to silence all of the ORNs innervating a specific glomerulus and recorded PN activity with two-photon calcium imaging and electrophysiology. We found evidence for balanced excitatory and inhibitory synaptic inputs but saw little or no response in the absence of direct ORN input. We next asked whether any transformation of activity occurs at successive layers of the antennal lobe. We found a strong link between PN firing and dendritic calcium elevation, the latter of which is tightly correlated with calcium activity in ORN axons, supporting the idea of glomerular propagation of olfactory information. Finally, we showed that odors are represented by a sparse population of PNs. Together, these results are consistent with the idea that direct receptor input provides the main excitatory drive to PNs, whereas interneurons modulate PN output. Balanced excitatory and inhibitory interneuron input may provide a mechanism to adjust PN sensitivity.This publication has 43 references indexed in Scilit:
- Excitatory Interactions between Olfactory Processing Channels in the Drosophila Antennal LobeNeuron, 2007
- Excitatory Local Circuits and Their Implications for Olfactory Processing in the Fly Antennal LobeCell, 2007
- The molecular receptive range of an olfactory receptorin vivo(Drosophila melanogasterOr22a)Journal of Neurobiology, 2006
- Coding of Odors by a Receptor RepertoireCell, 2006
- Molecular, Anatomical, and Functional Organization of the Drosophila Olfactory SystemCurrent Biology, 2005
- Representation of the Glomerular Olfactory Map in the Drosophila BrainCell, 2002
- Spatial Representation of the Glomerular Map in the Drosophila ProtocerebrumCell, 2002
- A Novel Family of Divergent Seven-Transmembrane Proteins: Candidate Odorant Receptors in DrosophilaNeuron, 1999
- On the actions that one nerve cell can have on another: Distinguishing “drivers” from “modulators”Proceedings of the National Academy of Sciences of the United States of America, 1998
- Representations of odours and odour mixtures visualized in the honeybee brainNature, 1997