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bioRxiv · 10.1101/2019.12.24.887679

Unc-4 acts to promote neuronal identity and development of the take-off circuit in the Drosophila CNS

Lacin, H.·Williamson, W. R.·Card, G. M.·Skeath, J. B.·Truman, J. W.
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Abstract

The Drosophila ventral nerve cord (VNC), the fly equivalent of the spinal cord, is composed of thousands of neurons that are born from a set of individually identifiable stem cells. The VNC harbors neuronal circuits required for the execution of vital behaviors, such as flying and walking. Taking advantage of the lineage-based functional organization of the VNC and genetic tools we developed, we investigated the molecular and developmental basis of behavior by focusing on lineage-specific functions of the homeodomain transcription factor, Unc-4. We found that Unc-4 functions in lineage 11A to promote cholinergic neurotransmitter identity and suppress the GABA fate. In 7B lineage, Unc-4 promotes proper neuronal projections to the leg neuropil, the hub for leg-related neuronal circuits and a specific flight-related take-off behavior. We also uncovered that Unc-4 acts peripherally to promote the development of proprioceptive sense organs and the abilities of flies to execute specific leg-related behaviors such as walking, climbing, and grooming. Our findings, thus, initiates the work on revealing molecular and developmental events that shape the VNC related behaviors.

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Lacin, H., Williamson, W. R., Card, G. M., Skeath, J. B., Truman, J. W.. 2019-12-24. Unc-4 acts to promote neuronal identity and development of the take-off circuit in the Drosophila CNS. https://doi.org/10.1101/2019.12.24.887679

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