Imaginal discs: Renaissance of a model for regenerative biology

Abstract

Many animals display a capacity to regenerate tissues or even a complete body. One of the main goals of regenerative biology is to identify the genes and genetic networks necessary for this process. Drosophila offers an ideal model system for such studies. The wide range of genetic and genomic approaches available for use in flies has helped in initiating the deciphering of the mechanisms underlying regeneration, and the results may be applicable to other organisms, including mammals. Moreover, most models of regeneration require experimental manipulation, whereas in Drosophila discrete domains can be ablated by genetically induced methods. Here, we present a summary of current research into imaginal disc regeneration and discuss the power of this tissue as a tool for understanding the genetics of regeneration.

Regulation of leg size and shape: Involvement of the Dachsous‐fat signaling pathway

“…Many questions such as what ultimately limits leg size and whether steepness of the Ds-Ft gradient promotes the growth of other organs and determines organ sizes remain unanswered. Of course, Drosophila offers an ideal model system for such studies: The wide range of genetic and genomic approaches available for use in flies has helped in elucidation of the mechanisms underlying determination of leg size and leg or wing disc regeneration (Bergantiñ os et al, 2010;Sun and Irvine, 2010). Recent evidence encouragingly suggests that the Wts-Hpo signaling pathway and Yki may act through the regulation of cell fate to control organ size in vertebrate systems (Dong et al, 2007;Lu et al, 2010;Pan, 2010;Zhao et al, 2010).…”

Imaginal disc regeneration takes flight

“…Experiments on imaginal disc regeneration were pioneered by the group of Ernst Hadorn ([3–6] and reviewed in [7, 8]). Although these studies revealed many fascinating aspects of regeneration including the propensity of tissues to change fate during regeneration (transdetermination) [9], the technical difficulties associated with these experiments curtailed the development of this field, and until recently, relatively few laboratories studied regeneration in imaginal discs.…”

Entre homéostasie et développement, quelles stratégies pour régénérer ?

“…Récemment, nous avons proposé que la prolifération compensatrice induite par l'apoptose agisse comme un mécanisme conservé capable de déclencher une réponse de type régénératif à une blessure. Ce mécanisme semble en effet être à l'oeuvre chez la larve de mouche qui régénère ses disques imaginaux (Fan & Bergmann, 2008a;Bergantinos et al, 2010;Morata et al, 2011), chez le têtard de Xénope qui régénère sa queue (Tseng et al, 2007), chez l'Hydre qui régénère sa tête après bissection mi-gastrique , ou chez la souris qui régénère sa peau ou son foie (Li et al, 2010). Par ailleurs l'apoptose a été détectée dans de nombreux contextes régénératifs tels que la planaire régénérant son corps (Hwang et al, 2004;Pellettieri et al, 2009).…”