Organization of the Drosophila larval visual circuit
Visual systems transduce, process and transmit light-dependent environmental cues. Computation of visual features depends on photoreceptor neuron types (PR) present, organization of the eye and wiring of the underlying neural circuit. Here, we describe the circuit architecture of the visual system of Drosophila larvae by mapping the synaptic wiring diagram and neurotransmitters. By contacting different targets, the two larval PR-subtypes create two converging pathways potentially underlying the computation of ambient light intensity and temporal light changes already within this first visual processing center. Locally processed visual information then signals via dedicated projection interneurons to higher brain areas including the lateral horn and mushroom body. The stratified structure of the larval optic neuropil (LON) suggests common organizational principles with the adult fly and vertebrate visual systems. The complete synaptic wiring diagram of the LON paves the way to understanding how circuits with reduced numerical complexity control wide ranges of behaviors.
Article and author information
Bundesbehörden der Schweizerischen Eidgenossenschaft (31003A_169993)
- Simon G Sprecher
Seventh Framework Programme (ERC-2012-StG 309832-PhotoNaviNet)
- Simon G Sprecher
Howard Hughes Medical Institute
- James W Truman
- Marta Zlatic
- Albert Cardona
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Mani Ramaswami, Trinity College Dublin, Ireland
- Received: May 5, 2017
- Accepted: August 7, 2017
- Accepted Manuscript published: August 8, 2017 (version 1)
- Version of Record published: August 18, 2017 (version 2)
© 2017, Larderet 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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