A HHMI mini-documentary discussing the remarkable regenerative capabilities of the planarian, and how they are used to study stem cell biology (12 mins).
Narrated animation describing pluripotent stem cells in early embryo; adult stem cells; stem cell characteristics; and embryonic stem cell culture.
Planaria is rapidly emerging as a key system for the study of stem cells, regeneration and tissue homeostasis, however it is still a relatively new model organism. There are few planaria labs worldwide (see list on left panel) and none at the FHCRC. We do not have any books about the planaria model system in the Arnold library, but I hope the class reading materials, the lab websites and these online resources can guide you to further information. Online resources are not yet as prevalent and comprehensive as for the other model organisms that we have discussed.
1. The Exploratium has three great pages of information on Planaria. See the narrated time lapse microscopy video of the incredible regeneration in planaria after dramatic amputations. Also has an interactive section devoted to stem cell biology.
2. Schmidtea genome database : Integrates in a single web-accessible portal all available data associated with the planarian genome.
3. Database of planarian resources on the web.
4. Planaria Blog: Like all the young 'uns these days..planaria has entered the "blogosphere"!
Planaria (flatworm) (Schmidtea mediterranea)
Lecture videos are available for viewing in the left column. They will be used to illustrate key points during class.
Required/Encouraged Reading
1. A basic overview of planarian model systems with an emphasis on Schmidtea mediterranea.
"Planarians" by Alejandro Sánchez Alvarado.
2. A review describing the historical background, molecular tools, and aspects of planarian life cycle that make them ideal models for studying regeneration and stem cell biology.
"Not your father's planarian: a classic model enters the era of functional genomics" by Phillip Newmark and Alejandro Sánchez Alvarado
3. An article describing the identification of planarian homologs of a mammalian tumor suppressor, PTEN. Implicates them in the control of stem cell maintenance during planarian regeneration, and indicates that their functional abrogation is sufficient to induce abnormal outgrowths.
"Planarian PTEN homologs regulate stem cells and regeneration through TOR signaling." by Néstor Oviedo et al.
Additional Reading
1. Review describing why the use of planarian stem cells (neoblasts) is allowing us to gain insights into stem cell biology.
Stem cells and the Planarian Schmidtea mediterranea by A, Sánchez Alvarado.
2 . In depth discussion of the cellular and morphogenetic processes that occur during regeneration in the planaria model system.
3. This review discusses two powerful regeneration models, the vertebrate urodele amphibians and invertebrate planarians, in light of cancer regulation.
"Regeneration: The origin of cancer or a possible cure?" by Néstor Oviedo and Wendy Beane.
1. Aziz Aboobaker's lab at the University of Nottingham: Evolution and development (Evo-devo) studies using planarians.
2. Kiyokazu Agata's lab at Kyoto University: Planarians in stem cell biology, brain and polarity research.
3. Kerstin Bartscherer's team at University of Heidelberg: Planarian regeneration and stem cell biology.
4. Michael Levin's lab at the Forsyth Institute: Embryonic development and regeneration, with a particular focus on the biophysics of cell behavior. Models include frogs, chicks, zebrafish, and planaria.
5. Nico Michiel's group at the University of Tubingen: Evolution of reproductive modes and mechanisms. Models include planaria, earthworms and sea slugs.
6. Phil Newmark's lab at University of Illinois at Urbana-Champaign: Molecular basis of regeneration in planaria.
7. Nikolaus Rajewsky's group at MDC Berlin: Role of small RNAs in planarian regeneration (also use other model systems like worm and fly).
8. Peter Reddien's lab at Massachussetts Institute of Technology: Molecular and cellular mechanisms controlling regeneration in planaria.
9. Planarian Groups at the University of Barcelona: Francesc Cebrià's lab, Rafael Romero's lab ,and Emili Saló's group.
Study embryonic development, reproduction, regeneration, homeostasis & ecosystems of planaria.
10. Alejandro Sanchez's lab at The University of Utah: Planarians in stem cell biology, regeneration and cancer.