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Sleep is ancient and genetically conserved across phylogeny. Neuropeptide signaling plays a fundamental role in the regulation of sleep for mammals, fish, and invertebrates like Caenorhabditis elegans. Developmentally timed-sleep and stress-induced sleep of C. elegans are controlled by distinct and overlapping neuropeptide pathways. The RPamide neuropeptides nlp-2, nlp-22, and nlp-23, play antagonistic roles during the regulation of developmentally-timed sleep, however, their role in stress-induced sleep has not been explored. These genes are linked on the X chromosome, which has made genetic analyses challenging. Here we used CRISPR to generate new alleles of nlp-22 and nlp-23, nlp-22;nlp-23 double mutants, and nlp-2;nlp-22;nlp-23 triple mutants. Confirming previous studies, we find that nlp-22 is required for developmentally-timed sleep, and show that nlp-23 is also required. However, all three genes are dispensable for stress-induced sleep.
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Orcokinin neuropeptides regulate sleep in Caenorhabditis elegans
Orcokinin neuropeptides are conserved among ecdysozoans, but their functions are incompletely understood. Here, we report a role for orcokinin neuropeptides in the regulation of sleep in the nematode Caenorhabditis elegans. The C. elegans orcokinin peptides, which are encoded by the nlp-14 and nlp-15 genes, are necessary and sufficient for quiescent behaviors during developmentally timed sleep (DTS) as well as during stress-induced sleep (SIS). The five orcokinin neuropeptides encoded by nlp-14 have distinct but overlapping functions in the regulation of movement and defecation quiescence during SIS. We suggest that orcokinins may regulate behavioral components of sleep-like states in nematodes and other ecdysozoans.
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- PAR ID:
- 10197932
- Date Published:
- Journal Name:
- Journal of Neurogenetics
- ISSN:
- 0167-7063
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1080/01677063.2020.1830084
