Iron is essential for survival of most organisms. All organisms have thus developed mechanisms to sense, acquire and sequester iron. In C. elegans, iron uptake and sequestration are regulated by HIF-1. We previously showed that hif-1 mutants are developmentally delayed when grown under iron limitation. Here we identify nhr-14, encoding a nuclear receptor, in a screen conducted for mutations that rescue the developmental delay of hif-1 mutants under iron limitation. nhr-14 loss upregulates the intestinal metal transporter SMF-3 to increase iron uptake in hif-1 mutants. nhr-14 mutants display increased expression of innate immune genes and DAF-16/FoxO-Class II genes, and enhanced resistance to Pseudomonas aeruginosa. These responses are dependent on the transcription factor PQM-1, which localizes to intestinal cell nuclei in nhr-14 mutants. Our data reveal how C. elegans utilizes nuclear receptors to regulate innate immunity and iron availability, and show iron sequestration as a component of the innate immune response.
RNA-seq data has been deposited in GEO under accession code GSE89783.In addition, raw RNA-seq data is reported in the source data files
NHR-14 loss of function couples intestinal iron uptake with innate immunity in C. elegans through PQM-1 signalingNCBI Gene Expression Omnibus, GSE89783.
- Elizabeth A Leibold
- Cole P Anderson
- Paul M Rindler
- Jason Gertz
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Bruno Lemaître, École Polytechnique Fédérale de Lausanne, Switzerland
© 2019, Rajan 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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