Nuclear receptor NR4A is required for patterning at the ends of the planarian anterior-posterior axis
Positional information is fundamental to animal regeneration and tissue turnover. In planarians, muscle cells express signaling molecules to promote positional identity. At the ends of the anterior-posterior (AP) axis, positional identity is determined by anterior and posterior poles, which are putative organizers. We identified a gene, nr4A, that is required for anterior- and posterior-pole localization to axis extremes. nr4A encodes a nuclear receptor expressed predominantly in planarian muscle, including strongly at AP-axis ends and the poles. nr4A RNAi causes patterning gene expression domains to retract from head and tail tips, and ectopic anterior and posterior anatomy (e.g., eyes) to iteratively appear more internally. Our study reveals a novel patterning phenotype, in which pattern-organizing cells (poles) shift from their normal locations (axis extremes), triggering abnormal tissue pattern that fails to reach equilibrium. We propose that nr4A promotes pattern at planarian AP axis ends through restriction of patterning gene expression domains.
Sequencing data and DESeq analysis have been deposited in GEO under accession codes GSE121048.
Nuclear receptor NR4A is required for patterning at the ends of the planarian anterior-posterior axisNCBI Gene Expression Omnibus, GSE121048.
Article and author information
Howard Hughes Medical Institute (Investigator)
- Peter W Reddien
National Institutes of Health (R01GM080639)
- Peter W Reddien
National Institutes of Health (T32GM007753)
- Dayan J Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Alejandro Sánchez Alvarado, Stowers Institute for Medical Research, United States
- Received: September 14, 2018
- Accepted: April 25, 2019
- Accepted Manuscript published: April 26, 2019 (version 1)
- Version of Record published: May 24, 2019 (version 2)
© 2019, Li 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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