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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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This content will become publicly available on January 1, 2026
Egg laying during stress-induced sleep of Caenorhabditis elegans is reduced due to behavioral quiescence and fertility defects
Sleep is a reversible state, characterized by the inhibition of periodic behaviors that occur during waking hours. Caenorhabditis elegans demonstrates stress-induced sleep following exposure to environmental stressors, like noxious heat or ultraviolet irradiation. During this time, animals inhibit movement, feeding, and defecation, behavioral quiescence largely controlled by neuropeptide signaling from the ALA and RIS sleep interneurons. Here, we tested whether egg retention and/or production which occurs during suboptimal environmental conditions, is regulated by the ALA and/or RIS, or other neuropeptides. We find that during stress-induced sleep, worms reduce egg-laying behavior and egg production (i.e., fertility). While the behavior is modestly modified in the absence of the ALA and RIS, as well as some neuropeptides, fertility is regulated by other mechanisms.
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- Award ID(s):
- 1845020
- PAR ID:
- 10616899
- Publisher / Repository:
- microPublication Biology
- Date Published:
- Journal Name:
- microPublication biology
- Volume:
- 2025
- ISSN:
- 2578-9430
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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