ON selectivity in Drosophila vision is a multisynaptic process involving both glutamatergic and GABAergic inhibition
- Johannes Gutenberg Universität Mainz, Germany
- Center of Advanced European Research (Caesar), Germany
Abstract
Sensory systems sequentially extract increasingly complex features. ON and OFF pathways, for example, encode increases or decreases of a stimulus from a common input. This ON/OFF pathway split is thought to occur at individual synaptic connections through a sign-inverting synapse in one of the pathways. Here, we show that ON selectivity is a multisynaptic process in the Drosophila visual system. A pharmacogenetics approach demonstrates that both glutamatergic inhibition through GluClα and GABAergic inhibition through Rdl mediate ON responses. Although neurons postsynaptic to the glutamatergic ON pathway input L1 lose all responses in GluClα mutants, they are resistant to a cell-type-specific loss of GluClα. This shows that ON selectivity is distributed across multiple synapses, and raises the possibility that cell-type-specific manipulations might reveal similar strategies in other sensory systems. Thus, sensory coding is more distributed than predicted by simple circuit motifs, allowing for robust neural processing.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files.
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RNA sequencing of Drosophila melanogaster optic lobe cell types.NCBI Gene Expression Omnibus, GSE103772.
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A GENETIC, GENOMIC, AND COMPUTATIONAL RESOURCE FOR EXPLORING NEURAL CIRCUIT FUNCTIONNCBI Gene Expression Omnibus, GSE116969.
Article and author information
Author details
Sebastian Molina-Obando
Funding
Deutsche Forschungsgemeinschaft (Emmy Noether SI 1991/1-1)
- Miriam Henning
- Burak Gür
- Junaid Akhtar
- Marion Silies
Deutsche Forschungsgemeinschaft (SFB889)
- Sebastian Molina-Obando
- Juan Felipe Vargas-Fique
Deutsche Forschungsgemeinschaft (Project C08)
- Sebastian Molina-Obando
- Juan Felipe Vargas-Fique
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Molina-Obando et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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ON selectivity in Drosophila vision is a multisynaptic process involving both glutamatergic and GABAergic inhibition
eLife 8:e49373.
https://doi.org/10.7554/eLife.49373
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