Changes to social feeding behaviors are not sufficient for the fitness gains of the C. elegans N2 reference strain
- Georgia Institute of Technology, United States
- The Rockefeller University, United States
Abstract
The standard reference Caenorhabditis elegans strain, N2, has evolved marked behavioral changes in social feeding behavior since its isolation from the wild. We show that the causal, laboratory-derived mutations in two genes, npr-1 and glb-5, confer large fitness advantages in standard laboratory conditions. Using environmental manipulations that suppress social/solitary behavior differences, we show the fitness advantages of the derived alleles remained unchanged, suggesting selection on these alleles acted through pleiotropic traits. Transcriptomics, developmental timing, and food consumption assays showed that N2 animals mature faster, produce more sperm, and consume more food than a strain containing ancestral alleles of these genes regardless of behavioral strategies. Our data suggest that the pleiotropic effects of glb-5 and npr-1 are a consequence of changes to O2 -sensing neurons that regulate both aerotaxis and energy homeostasis. Our results demonstrate how pleiotropy can lead to profound behavioral changes in a popular laboratory model.
Data availability
Sequencing data have been deposited in SRA under PRJNA437304.Source data file have been provided for all figures.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01GM114170)
- Yuehui Zhao
- Lijiang Long
- Wen Xu
- Richard F Campbell
- Edward E Large
- Patrick T McGrath
National Institute on Aging (R21AG050304)
- Patrick T McGrath
Ellison Medical Foundation (New Scholars in Aging)
- Lijiang Long
- Wen Xu
- Patrick T McGrath
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Zhao et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Changes to social feeding behaviors are not sufficient for the fitness gains of the C. elegans N2 reference strain
eLife 7:e38675.
https://doi.org/10.7554/eLife.38675
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