Abstract
Sleep is a dynamic process in most animals, involving distinct stages that probably perform multiple functions for the brain. Before sleep functions can be initiated, it is likely that behavioral responsiveness to the outside world needs to be reduced, even while the animal is still awake. Recent work in Drosophila has uncovered a sleep switch in the dorsal fan-shaped body (dFB) of the fly's central brain, but it is not known whether these sleep-promoting neurons also govern the acute need to ignore salient stimuli in the environment during sleep transitions. We found that optogenetic activation of the sleep switch suppressed behavioral responsiveness to mechanical stimuli, even in awake flies, indicating a broader role for these neurons in regulating arousal. The dFB-mediated suppression mechanism and its associated neural correlates requires innexin6 expression, suggesting that the acute need to reduce sensory perception when flies fall asleep is mediated in part by electrical synapses.
Highlights
Most animals sleep, and recent research suggests that some proposed sleep functions may be deeply conserved across all animals (Cirelli, 2009; Kirszenblat and van Swinderen, 2015; Zimmerman et al, 2008)
We found that behavioral responsiveness was significantly reduced after 1 min of red light, and that responsiveness was rapidly restored after the red light was turned off (Figure 2F), that is we observed no evidence of sleep inertia following 5 min of dorsal fan-shaped body (dFB) activation
Before sleep can begin to achieve any of its multiple putative functions, it would seem that behavioral responsiveness to the outside world first needs to be reduced
Summary
Recent research suggests that some proposed sleep functions may be deeply conserved across all animals (Cirelli, 2009; Kirszenblat and van Swinderen, 2015; Zimmerman et al, 2008). Even the smallest brains appear to have a sleep switch: in the fruit fly Drosophila melanogaster, the dorsal fan-shaped body (dFB) has been suggested to play a role that is analogous to that of the mammalian VLPO (Donlea et al, 2014, 2018; Pimentel et al, 2016). Activation of these neurons in the fly’s central brain promotes sleep and achieves key sleep functions (Dissel et al, 2015; Donlea et al, 2011). We examine how electrical and behavioral readouts of our sleep switch manipulations are affected when we remove innexin gap junctions from the dFB
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
