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bioRxiv · 10.1101/361667

Most sleep does not serve a vital function. Evidence from Drosophila melanogaster

Geissmann, Q.·Beckwith, E. J.·Gilestro, G. F.
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Abstract

Sleep appears to be a universally conserved phenomenon among the animal kingdom but whether this striking evolutionary conservation underlies a basic vital function is still an open question. Using novel technologies, we conducted an unprecedentedly detailed high-throughput analysis of sleep in the fruit fly Drosophila melanogaster, coupled with a life-long chronic and specific sleep restriction. Our results show that some wild-type flies are virtually sleepless in baseline conditions and that complete, forced sleep restriction is not necessarily a lethal treatment in wild-type Drosophila melanogaster. We also show that circadian drive, and not homeostatic regulation, is the main contributor to sleep pressure in flies. We propose a three-partite model framework of sleep function, according to which, total sleep accounts for three components: a vital component, a useful component, and an accessory component.

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Geissmann, Q., Beckwith, E. J., Gilestro, G. F.. 2018-07-04. Most sleep does not serve a vital function. Evidence from Drosophila melanogaster. https://doi.org/10.1101/361667

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