ZFIN ID: ZDB-PUB-170627-12
Light-Dependent Regulation of Sleep and Wake States by Prokineticin 2 in Zebrafish
Chen, S., Reichert, S., Singh, C., Oikonomou, G., Rihel, J., Prober, D.A.
Date: 2017
Source: Neuron   95(1): 153-168.e6 (Journal)
Registered Authors: Prober, David, Reichert, Sabine, Rihel, Jason
Keywords: circadian rhythm, galanin, masking, prokineticin 2, sleep, zebrafish
MeSH Terms:
  • Animals
  • Circadian Rhythm/genetics*
  • Galanin/genetics
  • Galanin/metabolism
  • Hypothalamus/metabolism
  • Light*
  • Mutation
  • Neuropeptides/genetics*
  • Receptors, G-Protein-Coupled/genetics
  • Receptors, G-Protein-Coupled/metabolism
  • Receptors, Peptide/genetics
  • Receptors, Peptide/metabolism
  • Sleep/genetics*
  • Wakefulness/genetics*
  • Zebrafish
  • Zebrafish Proteins/genetics*
  • Zebrafish Proteins/metabolism
PubMed: 28648499 Full text @ Neuron
Light affects sleep and wake behaviors by providing an indirect cue that entrains circadian rhythms and also by inducing a direct and rapid regulation of behavior. While circadian entrainment by light is well characterized at the molecular level, mechanisms that underlie the direct effect of light on behavior are largely unknown. In zebrafish, a diurnal vertebrate, we found that both overexpression and mutation of the neuropeptide prokineticin 2 (Prok2) affect sleep and wake behaviors in a light-dependent but circadian-independent manner. In light, Prok2 overexpression increases sleep and induces expression of galanin (galn), a hypothalamic sleep-inducing peptide. We also found that light-dependent, Prok2-induced sedation requires prokineticin receptor 2 (prokr2) and is strongly suppressed in galn mutants. These results suggest that Prok2 antagonizes the direct wake-promoting effect of light in zebrafish, in part through the induction of galn expression in the hypothalamus.