A mex3 homolog is required for differentiation during planarian stem cell lineage development
- The Hospital for Sick Children, Canada
- Terrence Donnelly Centre for Cellular and Biomedical Research, Canada
Abstract
Neoblasts are adult stem cells (ASCs) in planarians that sustain cell replacement during homeostasis and regeneration of any missing tissue. While numerous studies have examined genes underlying neoblast pluripotency, molecular pathways driving postmitotic fates remain poorly defined. Here we used transcriptional profiling of irradiation-sensitive and -insensitive cell populations and RNA interference (RNAi) functional screening to uncover markers and regulators of postmitotic progeny. We identified 32 new markers distinguishing two main epithelial progenitor populations, and a planarian homolog to the MEX3 RNA-binding protein (Smed-mex3-1) as a key regulator of lineage progression. mex3-1 was required for generating differentiated cells of multiple lineages, while restricting the size of the stem cell compartment. We also demonstrated the utility of using mex3-1(RNAi) animals to identify additional progenitor markers. These results identified mex3-1 as a cell fate regulator, broadly required for differentiation, and suggest that mex3-1 helps mediate the balance between ASC self-renewal and commitment.
Article and author information
Author details
Reviewing Editor
- Marianne E Bronner, California Institute of Technology, United States
Version history
- Received: February 14, 2015
- Accepted: June 25, 2015
- Accepted Manuscript published: June 26, 2015 (version 1)
- Version of Record published: July 20, 2015 (version 2)
Copyright
© 2015, Zhu 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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A mex3 homolog is required for differentiation during planarian stem cell lineage development
eLife 4:e07025.
https://doi.org/10.7554/eLife.07025
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