The current goals of this research are to characterize the systemic responses to tissue regeneration after injury in insects, such as delays in developmental that provide time for the repair of select tissues. Many tissues display an impressive ability for repair and regeneration after injury. This is seen in invertebrate and vertebrate tissues and even in digit replacement in humans in utero. Compensatory growth and regeneration are vital processes used to replace damaged tissue during animal development. Responses to tissue injury and regeneration include inflammation or reduced growth in neighboring cells, as well as changes in growth rate including delays in development. Much is known of the local responses to tissue damage, but there is a gap in information on how local signals produce systemic immune and developmental responses. Insect imaginal discs, the precursors to adult structures such as wings, show exceptional regenerative capabilities, where they secrete signals that delay development when damaged. This project will (i) the characterize responses of the immune system after damage to the imaginal discs, (ii) identify and characterize the factors released from the damaged discs providing signals to the endocrine system, and (ii) determine the actions of these blood-borne factors on the endocrine system. This research will be conducted on the larger insect, Manduca sexta, as a means of developing a complementary model organism to the genetically tractable, but smaller fruitfly, Drosophila melanogaster. Given the mentorship by Dr. Hariharan of UC Berkeley, this pilot project will broaden the scope of the PI's expertise in immunology and development for understanding how development is modulated in response to external stresses, and how tissues interact to monitor changes in growth and body size during development. It will also provide the learning environment for introducing Drosophila genetics to the lab when necessary.
This research broadens our understanding of local responses to tissue repair, looking at the systemic effects of tissue injury. A number of inflammatory diseases such as Cystic Fibrosis or Crohn's display changes in growth and puberty onset, while insulin insensitivity is a result of chronic inflammation. Understanding how signals from damaged tissue interact with the immune system and peripheral endocrine tissues to alter development are key to addressing these problems. Finally, this research may also help understand the damage induced by x-rays during cancer treatments.