Abstract

Planarian neoblasts are pluripotent, adult somatic stem cells and lineage-primed progenitors required for production and maintenance of all differentiated cell types, including the germline. Neoblasts, originally defined as undifferentiated cells residing in the adult parenchyma, are frequently compared to embryonic stem cells yet their developmental origin remains obscure. We investigated the provenance of neoblasts during S. mediterranea embryogenesis, and report that neoblasts arise from an anarchic, cycling piwi-1+ population wholly responsible for production of all temporary and definitive organs during embryogenesis. Early embryonic piwi-1+ cells are molecularly and functionally distinct from neoblasts: they express unique cohorts of early embryo enriched transcripts and behave differently than neoblasts in cell transplantation assays. Neoblast lineages arise as organogenesis begins and are required for construction of all major organ systems during embryogenesis. These subpopulations are continuously generated during adulthood, where they act as agents of tissue homeostasis and regeneration.

Article and author information

Author details

  1. Erin L Davies

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  2. Kai Lei

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  3. Christopher W Seidel

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  4. Amanda E Kroesen

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  5. Sean A McKinney

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  6. Longhua Guo

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  7. Sofia MC Robb

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  8. Eric J Ross

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  9. Kirsten Gotting

    Stowers Institute for Medical Research, Kansas City, United States
    Competing interests
    No competing interests declared.
  10. Alejandro Sánchez Alvarado

    Stowers Institute for Medical Research, Kansas City, United States
    For correspondence
    asa@stowers.org
    Competing interests
    Alejandro Sánchez Alvarado, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1966-6959

Funding

National Institute of General Medical Sciences (R37GM057260-17)

  • Alejandro Sánchez Alvarado

Howard Hughes Medical Institute

  • Kai Lei

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Utpal Banerjee, University of California, Los Angeles, United States

Version history

  1. Received: August 30, 2016
  2. Accepted: January 4, 2017
  3. Accepted Manuscript published: January 10, 2017 (version 1)
  4. Version of Record published: February 6, 2017 (version 2)

Copyright

© 2017, Davies 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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  1. Erin L Davies
  2. Kai Lei
  3. Christopher W Seidel
  4. Amanda E Kroesen
  5. Sean A McKinney
  6. Longhua Guo
  7. Sofia MC Robb
  8. Eric J Ross
  9. Kirsten Gotting
  10. Alejandro Sánchez Alvarado
(2017)
Embryonic origin of adult stem cells required for tissue homeostasis and regeneration
eLife 6:e21052.
https://doi.org/10.7554/eLife.21052

Share this article

https://doi.org/10.7554/eLife.21052

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