PT  - JOURNAL ARTICLE
AU  - Veit Grabe
AU  - Marco Schubert
AU  - Martin Strube-Bloss
AU  - Anja Reinert
AU  - Silke Trautheim
AU  - Sofia Lavista-Llanos
AU  - André Fiala
AU  - Bill S. Hansson
AU  - Silke Sachse
TI  - Odor-Induced Multi-Level Inhibitory Maps in <em>Drosophila</em>
AID  - 10.1523/ENEURO.0213-19.2019
DP  - 2020 Jan 01
TA  - eneuro
PG  - ENEURO.0213-19.2019
VI  - 7
IP  - 1
4099  - http://www.eneuro.org/content/7/1/ENEURO.0213-19.2019.short
4100  - http://www.eneuro.org/content/7/1/ENEURO.0213-19.2019.full
SO  - eNeuro2020 Jan 01; 7
AB  - Optical imaging of intracellular Ca2+ influx as a correlate of neuronal excitation represents a standard technique for visualizing spatiotemporal activity of neuronal networks. However, the information-processing properties of single neurons and neuronal circuits likewise involve inhibition of neuronal membrane potential. Here, we report spatially resolved optical imaging of odor-evoked inhibitory patterns in the olfactory circuitry of Drosophila using a genetically encoded fluorescent Cl- sensor. In combination with the excitatory component reflected by intracellular Ca2+ dynamics, we present a comprehensive functional map of both odor-evoked neuronal activation and inhibition at different levels of olfactory processing. We demonstrate that odor-evoked inhibition carried by Cl- influx is present both in sensory neurons and second-order projection neurons (PNs), and is characterized by stereotypic, odor-specific patterns. Cl--mediated inhibition features distinct dynamics in different neuronal populations. Our data support a dual role of inhibitory neurons in the olfactory system: global gain control across the neuronal circuitry and glomerulus-specific inhibition to enhance neuronal information processing.