Temporal identity establishes columnar neuron morphology, connectivity, and function in a Drosophila navigation circuit
The insect central complex (CX) is a conserved brain region containing 60+ neuronal subtypes, several of which contribute to navigation. It is not known how CX neuronal diversity is generated or how developmental origin of subtypes relates to function. We mapped the developmental origin of four key CX subtypes and found that neurons with similar origin have similar axon/dendrite targeting. Moreover, we found that the temporal transcription factor (TTF) Eyeless/Pax6 regulates the development of two recurrently-connected CX subtypes: Eyeless loss simultaneously produces ectopic P-EN neurons with normal axon/dendrite projections, and reduces the number of E-PG neurons. Furthermore, transient loss of Eyeless during development impairs adult flies' capacity to perform celestial navigation. We conclude that neurons with similar developmental origin have similar connectivity, that Eyeless maintains equal E-PG and P-EN neuron number, and that Eyeless is required for the development of circuits that control adult navigation.
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Howard Hughes Medical Institute
- Chris Q Doe
National Institutes of Health (T32HD007348)
- Chris Q Doe
National Institutes of Health (HD27058)
- Chris Q Doe
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- K VijayRaghavan, National Centre for Biological Sciences, Tata Institute of Fundamental Research, India
- Received: November 21, 2018
- Accepted: January 31, 2019
- Accepted Manuscript published: February 1, 2019 (version 1)
- Accepted Manuscript updated: February 6, 2019 (version 2)
- Version of Record published: February 22, 2019 (version 3)
- Version of Record updated: March 11, 2019 (version 4)
© 2019, Sullivan 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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