Opposing subclasses of Drosophila ellipsoid body neurons promote and suppress sleep

Aleman, A.; Omoto, J. J.; Singh, P.; Nguyen, B.-C.; Kandimalla, P.; Hartenstein, V.; Donlea, J. M.

doi:10.1101/2021.10.19.464469

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bioRxiv · 10.1101/2021.10.19.464469

Opposing subclasses of Drosophila ellipsoid body neurons promote and suppress sleep

Aleman, A.·Omoto, J. J.·Singh, P.·Nguyen, B.-C.·Kandimalla, P.·Hartenstein, V.·Donlea, J. M.

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Abstract

Recent work in Drosophila has uncovered several neighboring classes of sleep-regulatory neurons within the central complex. However, the logic of connectivity and network motifs remains limited by the incomplete examination of relevant cell types. Using a recent genetic-anatomical classification of ellipsoid body ring neurons, we conducted a thermogenetic screen to assess sleep/wake behavior and discovered two opposing populations: sleep-promoting R3m and wake-promoting R3d neurons. Activation of these neurons influences sleep duration and architecture by prolonging or shortening sleep bouts, suggesting a key role in sleep maintenance. R3m and R3d neurons are GABAergic and require GABA synthesis for their effects on sleep. Finally, we use a fluorescent reporter for putative synaptic partners to embed these neurons within the known sleep-regulatory network; R3m and R3d neurons lay downstream of wake-active Helicon cells, and R3m neurons likely inhibit R3d neurons. Together, the data presented herein suggest a neural mechanism by which previously uncharacterized circuit elements operate within the sleep homeostat to stabilize sleep-wake states.

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Aleman, A., Omoto, J. J., Singh, P., Nguyen, B.-C., Kandimalla, P., Hartenstein, V., Donlea, J. M.. 2021-10-19. Opposing subclasses of Drosophila ellipsoid body neurons promote and suppress sleep. https://doi.org/10.1101/2021.10.19.464469

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