Abstract
Whole-body regeneration requires adult stem cells with high plasticity to differentiate into missing cell types. Planarians possess a unique configuration of organs embedded in a vast pool of pluripotent stem cells. How stem cells integrate positional information with discrete fates remains unknown. Here, we use the planarian pharynx to define the cell fates that depend on the pioneer transcription factor FoxA. We find that Roundabout receptor RoboA suppresses aberrant pharynx cell fates by altering foxA expression, independent of the canonical ligand Slit. An RNAi screen for extracellular proteins identifies Anosmin1a as a potential partner of RoboA. Perturbing global patterning demonstrates that roboA/anosmin1a functions locally in the brain. By contrast, altering pharynx fate with foxA knockdown induces head-specific neurons in the pharynx, indicating a latent plasticity of stem cells. Our data links critical extracellular cues with cell fate decisions of highly plastic stem cells, ensuring the fidelity of organ regeneration.
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Data availability
All data are available upon request. The scRNA-seq data generated in this study have been deposited into the GEO database under Accession number GSE292456. Source data are provided with this paper.
Code availability
Codes have been deposited on Github (https://github.com/kw572/RoboA)95.
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Acknowledgements
We would like to thank members of the Adler laboratory for insight on this project; T. Inoue for kindly sharing the Arrestin antibody; and T. Tumbar for critical reading of the manuscript. We thank the Cornell University Biotechnology Resource Center’s Flow Cytometry (RRID:SCR_021740), Imaging (RRID:SCR_021741), and Genomics (RRID:SCR_021727) cores for equipment and resources used in this project. This work was funded by a National Institutes of Health grant R01GM139933 to C.E.A., a Cornell University Stem Cell Program fellowship (to K-T.W), Cornell University Center for Vertebrate Genomics Scholarship (to K-T.W.) and a Taiwan Ministry of Education scholarship (to K-T.W.), and a T32 GM144292 (to I.E.W.).
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K-T.W., Y-C.C. and C.E.A. conceived the study. C.E.A. supervised the research and acquired funding. K-T.W., Y-C.C., F-Y.T. and C.P.J. performed the ISH, RNAi, qRT-PCR and imaging experiments. K-T.W. generated the sequencing data and performed all statistical analyses. I.E.W. and E.O. performed biochemical assays. K-T.W. and C.E.A. wrote the original draft. All authors edited, read, and approved the manuscript.
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Wang, KT., Tsai, FY., Chen, YC. et al. RoboA reinforces planarian stem cell fate through FoxA and Anosmin1a. Nat Commun (2026). https://doi.org/10.1038/s41467-026-68656-1
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DOI: https://doi.org/10.1038/s41467-026-68656-1
