Extensive intraspecies cryptic variation in an ancient embryonic gene regulatory network
- University of Auckland, New Zealand
- University of California, Santa Barbara, United States
Abstract
Innovations in metazoan development arise from evolutionary modification of gene regulatory networks (GRNs). We report widespread cryptic variation in the requirement for two key regulatory inputs, SKN-1/Nrf2 and MOM-2/Wnt, into the C. elegans endoderm GRN. While some natural isolates show a nearly absolute requirement for these two regulators, in others, most embryos differentiate endoderm in their absence. GWAS and analysis of recombinant inbred lines reveal multiple genetic regions underlying this broad phenotypic variation. We observe a reciprocal trend, in which genomic variants, or knockdown of endoderm regulatory genes, that result in a high SKN-1 requirement often show low MOM-2/Wnt requirement and vice-versa, suggesting that cryptic variation in the endoderm GRN may be tuned by opposing requirements for these two key regulatory inputs. These findings reveal that while the downstream components in the endoderm GRN are common across metazoan phylogeny, initiating regulatory inputs are remarkably plastic even within a single species.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
National Institutes of Health (1R01HD082347)
- Joel H Rothman
National Institutes of Health (1R01HD081266)
- Joel H Rothman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Antonis Rokas, Vanderbilt University, United States
Version history
- Received: May 6, 2019
- Accepted: August 15, 2019
- Accepted Manuscript published: August 15, 2019 (version 1)
- Version of Record published: September 20, 2019 (version 2)
Copyright
© 2019, Torres Cleuren 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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Extensive intraspecies cryptic variation in an ancient embryonic gene regulatory network
eLife 8:e48220.
https://doi.org/10.7554/eLife.48220
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