3) Studies of regeneration in Drosophila

The fundamental question in the study of regeneration is why some animals have a remarkable capacity to regenerate damaged tissues while others do not. For instance, while urodele amphibians (salamanders, newts) are capable of regenerating their limbs after amputation, mammalian limbs have very little regenerative capacity. Similarly, in many species, less regenerative capacity is observed in adults than at earlier stages of development. The long term goal of our research is to understand the genetic pathways that regulate the capacity of a tissue for regenerative growth.

The imaginal discs of Drosophila larvae are capable of regenerating missing portions when implanted into the abdomen of adult females. However, these experiments are technically difficult and not easily incorporated into large-scale genetic screens.

The traditional way of studying imaginal disc regeneration	Our system allows the study of imaginal disc regeneration in situ

(Drawings by Melanie Worley)

To take advantage of the powerful tools of fly genetics, we have devised a way of studying tissue regeneration in Drosophila that does not require surgical manipulations. Using a temperature shift, we are able to ablate the portion of the larval wing imaginal disc that gives rise to the wing blade of the adult, and to study the ensuing regenerative growth. We can easily score the extent of regeneration by examining the size of the wings of adult flies. Our laboratory is currently using this method to study the properties of regenerative growth and to conduct genetic screens for genes that regulate tissue regeneration.

We have recently published some of this work in the following publication:

Smith-Bolton RK, Worley MI, Kanda H, Hariharan IK (2009) Regenerative growth in Drosophila imaginal discs is regulated by Wingless and Myc. Developmental Cell 16:797-809. (PubMed Link)

This work was discussed in a "Preview" published in Developmental Cell by Nachtrab and Poss (PubMed Link)