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Planarian Regeneration pp 57–172Cite as

Stem Cells, Patterning and Regeneration in Planarians: Self-Organization at the Organismal Scale

Part of the Methods in Molecular Biology book series (MIMB,volume 1774)

Abstract

The establishment of size and shape remains a fundamental challenge in biological research that planarian flatworms uniquely epitomize. Planarians can regenerate complete and perfectly proportioned animals from tiny and arbitrarily shaped tissue pieces; they continuously renew all organismal cell types from abundant pluripotent stem cells, yet maintain shape and anatomy in the face of constant turnover; they grow when feeding and literally degrow when starving, while scaling form and function over as much as a 40-fold range in body length or an 800-fold change in total cell numbers. This review provides a broad overview of the current understanding of the planarian stem cell system, the mechanisms that pattern the planarian body plan and how the interplay between patterning signals and cell fate choices orchestrates regeneration. What emerges is a conceptual framework for the maintenance and regeneration of the planarian body plan on basis of the interplay between pluripotent stem cells and self-organizing patterns and further, the general utility of planarians as model system for the mechanistic basis of size and shape.

Key words

  • Planaria
  • Pluripotent stem cells
  • Regeneration
  • Patterning
  • Self-organization
  • Shape and size

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Acknowledgments

I thank the members of the Rink lab for lively discussions and colleagues at the MPI-CBG and in the planarian community for helpful comments. I apologize to all authors whose work I have not cited in the interest of maintaining the flow of the text.

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    Jochen C. Rink

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Rink, J.C. (2018). Stem Cells, Patterning and Regeneration in Planarians: Self-Organization at the Organismal Scale. In: Rink, J. (eds) Planarian Regeneration. Methods in Molecular Biology, vol 1774. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-7802-1_2

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