Speaker: Ping Kang, graduate student

Major professor: Jo Anne Powell-Coffman, genetics, development and cell biology professor

Title: "Hormonal regulation of aging and homeostasis in Drosophila melanogaster"

Abstract: The prothoracicotropic hormone (PTTH) is well-known for its important role in controlling insect developmental timing and body size by promoting the biosynthesis and release of ecdysone. However, the role of PTTH in adult insects is largely unexplored. Here we show that PTTH transcripts are detected in both male and female Drosophila.  Intriguingly, PTTH null mutants (both males and females) show extended lifespan and exhibit increased resistance to oxidative stress. Consistently, PTTH mutants show well-preserved muscle and cardiac function at old ages. IMD (Immunity Deficiency Pathway) was identified through RNA sequence analysis with young versus old wildtype and PTTH mutant female flies. Especially DptA gene expression in Oenocytes phenocopied PTTH mutant, suggesting that PTTH targets oenocytes specifically. Furthermore, the extension of lifespan in female PTTH mutants was regulated through PTTH -Torso stimulated imd pathway in PG (protharocic gland), consequently oenocyte was remodeled during the development stage, which suggests PTTH plays a role in oenocytes function. Overall, we report that PTTH regulates aging through IMD pathway, especially in oenocyte tissue, liver-like tissue in drosophila. Together, our data reveal a novel function of PTTH in longevity regulation and immunity response in adult Drosophila.