Gradients in Planarian Regeneration and Homeostasis

Adell, Teresa; Cebrià, Francesc; Saló, Emili

doi:10.1101/cshperspect.a000505

Cited by 92 publications

(61 citation statements)

References 57 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, this time scale is set by morphogen diffusion and system size. For example, assuming a maximum diffusion coefficient of 100 µm 2 /s and a maximum organism size of 20 mm, relevant for the flatworms considered, we infer a patterning time scale of 3 − 30 days, roughly consistent with the experimental range of 1−2 weeks for the restoration of body plan proportions after amputation [24,26]. Note that transport processes such as active mixing could accelerate morphogen dispersal, and thus allow for faster pattern formation [10].…”

Section: Discussionsupporting

confidence: 78%

Scaling and Regeneration of Self-Organized Patterns

et al. 2015

View full text Add to dashboard Cite

Biological patterns generated during development and regeneration often scale with organism size. Some organisms, e.g., flatworms, can regenerate a rescaled body plan from tissue fragments of varying sizes. Inspired by these examples, we introduce a generalization of Turing patterns that is self-organized and self-scaling. A feedback loop involving diffusing expander molecules regulates the reaction rates of a Turing system, thereby adjusting pattern length scales proportional to system size. Our model captures essential features of body plan regeneration in flatworms as observed in experiments.

show abstract

Section: Discussionsupporting

confidence: 78%

Scaling and Regeneration of Self-Organized Patterns

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The cellular and molecular basis of positional memory and their comparative aspects in different taxa are not well understood. In regenerating planarians, for example, expression dynamics of Wnt/β-catenin and BMP signaling pathways, which control anterior-posterior and dorsoventral axes regeneration, respectively, seem to confirm the establishment of morphogenetic gradients as mechanisms of repatterning, as suggested originally by Morgan (Morgan, 1901;Adell et al, 2010;Umesono et al, 2013). How neoblasts and cells in the blastema can interpret the gradients and whether these gradients are present in the adult or induced by injury is still uncertain.…”

Section: Morphogenetic Events In Regenerationmentioning

confidence: 93%

“…Wnt, BMP and Nodal represent the signaling pathways defining the body axes during embryonic development, at least in bilaterians. These pathways were possibly present in the most recent common ancestor of all metazoans (reviewed in Holstein et al, 2011) and their involvement in whole body or body structure re-patterning has been reported in cnidarians, acoel, platyhelminthes, and deuterostomes (Holstein et al, 2003;Yakushiji et al, 2009;Adell et al, 2010;Reddien, 2011;Srivastava et al, 2014;Watanabe et al, 2014).…”

Section: Morphogenetic Events In Regenerationmentioning

confidence: 99%

Reconsidering regeneration in metazoans: an evo-devo approach

Tiozzo

Copley

2015

Front. Ecol. Evol.

View full text Add to dashboard Cite

Regeneration of body structures is an ability widely but unevenly distributed amongst the animal kingdom. Understanding regenerative biology in metazoans means understanding the multiplicity of the cellular and molecular mechanisms that lead to the differentiation, morphogenesis and ultimately the development of a particular regenerating unit. In this manuscript we critically assess the evolutionary considerations suggesting that regeneration is an ancestral trait rather than a mechanism independently evolved in different taxa. As a general method to test evolutionary hypothesis on regeneration, we propose mechanistically dissecting the regenerative processes according to its conserved chronological steps: wound healing, mobilization of cell precursors and morphogenesis. We then suggest interpreting regenerative biology from an evo-devo perspective, proposing a possible theoretical framework and experimental approaches without necessarily invoking a common origin or only multiple losses of regenerative capabilities.

show abstract

“…in metazoan development have crucial roles during planarian regeneration, such as involvement in stem cell regulation, organ regeneration and body patterning (Sánchez Alvarado, 2007;Forsthoefel and Newmark, 2009;Adell et al, 2010;Shibata et al, 2010;Aboobaker, 2011;Reddien, 2011). The Smed-pbx RNAi phenotype described here identifies pbx as a new player in multiple steps of planarian regeneration and homeostatic tissue turnover.…”

Section: Research Articlementioning

confidence: 95%

pbx is required for pole and eye regeneration in planarians

2013

View full text Add to dashboard Cite

Planarian regeneration involves regionalized gene expression that specifies the body plan. After amputation, planarians are capable of regenerating new anterior and posterior poles, as well as tissues polarized along the anterior-posterior, dorsal-ventral and medial-lateral axes. Wnt and several Hox genes are expressed at the posterior pole, whereas Wnt inhibitory genes, Fgf inhibitory genes, and prep, which encodes a TALE-family homeodomain protein, are expressed at the anterior pole. We found that Smed-pbx (pbx for short), which encodes a second planarian TALE-family homeodomain transcription factor, is required for restored expression of these genes at anterior and posterior poles during regeneration. Moreover, pbx(RNAi) animals gradually lose pole gene expression during homeostasis. By contrast, pbx was not required for initial anterior-posterior polarized responses to wounds, indicating that pbx is required after wound responses for development and maintenance of poles during regeneration and homeostatic tissue turnover. Independently of the requirement for pbx in pole regeneration, pbx is required for eye precursor formation and, consequently, eye regeneration and eye replacement in homeostasis. Together, these data indicate that pbx promotes pole formation of body axes and formation of regenerative progenitors for eyes.

show abstract

Gradients in Planarian Regeneration and Homeostasis

Cited by 92 publications

References 57 publications

Scaling and Regeneration of Self-Organized Patterns

Scaling and Regeneration of Self-Organized Patterns

Reconsidering regeneration in metazoans: an evo-devo approach

pbx is required for pole and eye regeneration in planarians

Contact Info

Product

Resources

About