Severe yet nonlethal disruptions to sleep trigger protective responses, e.g., for restoring proteostasis. Identifying these mechanisms can inform on fundamental functions of sleep. In contrast to environmental stressors, C. elegans sleep deprivation has been minimally explored. We examine ill effects of 'worm tiredness' in different physiological and developmental contexts.
Worm sleep homeostasis
A key characteristic of sleep is its intricate homeostatic regulation: following disruptions, ‘restoring forces’ extend or modify sleep to compensate for the loss. It has been (implicitly) assumed that a single mechanism is responsible for adjusting the sleep cycle after any disturbance, regardless of its severity. We identified distinct homeostatic mechanisms in C. elegans. Similar notions were demonstrated in fruit flies and may plausibly exist in mammalian sleep.
Regulation of locomotion, feeding, and quiescence
Biogenic amines play important roles in many brain functions and C. elegans has conserved mechanisms for regulating feeding, metabolism, motion, and quiescence. Our data suggests that serotonin is key to rapidly responding to a newly encountered food in a patchy foraging environment and that worm feeding is regulated by committing to bursts of regular pumping.
Sleep may be universal in the animal kingdom. Yet, why animals sleep and the underlying reason for this universality remain controversial questions. Do all animals sleep? What is the natural history of sleep? How and over what period did it first appear? What are the links between development and sleep? When does a developing animals first sleep and why? What is the core function of sleep?
A scalable method for automatically measuring pharyngeal pumping in C. elegans
Monika Scholz, Dylan J. Lynch, Kyung Suk Lee, Erel Levine, David Biron
Journal of Neuroscience Methods (in press)
Serotonin promotes exploitation in complex environments by accelerating decision-making
Iwanir, Shachar, Adam S. Brown, Stanislav Nagy, Dana Najjar, Alexander Kazakov, Kyung Suk Lee, Alon Zaslaver, Erel Levine, and David Biron.
BMC biology 14.1 (2016): 1.
Sleep and Development in Genetically Tractable Model Organisms.
Kayser, M. S., and Biron, D.
Genetics 203.1 (2016): 21-33.
A Generative Statistical Algorithm for Automatic Detection of Complex Postures.
Nagy, S., Goessling, M., Amit, Y., and Biron, D.
PLoS Comput Biol 11.10 (2015): e1004517.
Homeostasis in C. elegans sleep is characterized by two behaviorally and genetically distinct mechanisms.
Nagy, S., Tramm, N., Sanders, J., Iwanir, S., Shirley, I. A., Levine, E., and Biron, D.
eLife 3 (2014): e04380.
A longitudinal study of Caenorhabditis elegans larvae reveals a novel locomotion switch, regulated by Gαs signaling
Stanislav Nagy, Charles Wright, Nora Tramm, Nicholas Labello, Stanislav Burov, David Biron
eLife 2 (2013): e00782