Tissue damage caused by trauma or chronic illness reduces quality of life and shortens life expectancy. The
ability to regulate the endogenous response to damage, and to induce regenerative growth, would have profound
implications for the field of regenerative medicine. The Smith-Bolton lab has developed innovative techniques
to: 1) induce tissue damage in hundreds of animals simultaneously, enabling the use of powerful Drosophila
genetics to identify mechanisms that regulate tissue regeneration, and 2) isolate the regenerating tissue, ena-
bling high-throughput genomic approaches to characterize the molecular mechanisms that underly regeneration
control. The long-term goal of the Smith-Bolton lab is to understand how damaged tissue regenerates a func-
tional structure. During the past five years, funded by NIH R01GM107140 “Regulation of Cell Fate and Patterning
during Regenerative Growth”, the lab has used genetic and genomic techniques to 1) demonstrate that regen-
eration signaling and unconstrained expression of regeneration growth factors have deleterious side effects, 2)
identify several protective factors that prevent these unwanted outcomes, and 3) identify multiple mechanisms
through which the magnitude and duration of regeneration signaling are tightly controlled. The purpose of this
R35 MIRA application is to obtain stable and flexible funding to continue our successful and innovative work
identifying the intricate pathways that control tissue regeneration. Important questions remain unanswered, such
as 1) How do tissue-damage signals induce the changes in gene expression that carry out each step in regen-
eration? 2) How does the regenerating tissue switch back to its normal patterning and gene expression profile?
3) Does regeneration recapitulate development, or are there regeneration-specific patterning controls? The re-
search programs in the Smith-Bolton lab over the next five years will seek to achieve specific goals, including
using genetic, genomic, and molecular techniques to: 1) identify the transcription factors and the genetic targets
of those factors that constitute the gene regulatory networks that control individual steps in regeneration, 2)
provide a detailed understanding of how key genomic loci are regulated after tissue damage, 3) elucidate the
mechanism through which regenerating tissue returns to normal, and 4) identify additional regeneration-specific
regulators of cell fate and patterning. When this work is complete, we will have a mechanistic understanding of
how regeneration can derail cell fate, and the variety of mechanisms used to prevent catastrophic changes in
gene expression after tissue damage. This work will have a critical positive impact because strategies developed
to induce medically relevant regrowth of tissue after acute injury or chronic illness must account for deleterious
side effects of pro-regeneration signals and incorporate protective factors to prevent aberrations. Furthermore,
this work will identify candidate genes that can be targeted to manipulate specific aspects of the tissue damage
response, while avoiding unwanted effects such as overstimulation of the wound response or unregulated pro-
liferation, both in model systems and in humans.