20-hydroxyecdysone (20E) Signaling Delay in Starvation Resistant Drosophila


Meeting Abstract

16.2  Friday, Jan. 4  20-hydroxyecdysone (20E) Signaling Delay in Starvation Resistant Drosophila REYNOLDS, L. A.*; GIBBS, A. G.; University of Nevada, Las Vegas; University of Nevada, Las Vegas reyno172@unlv.nevada.edu

We selected for adult starvation resistance in replicated outbred populations of Drosophila melanogaster. These populations accumulate greater lipid stores as larvae that they then use to survive adult starvation. Lipids are accumulated during the 3rd instar larval feeding period, which is ~24 hr longer in starvation-selected populations than controls; the rate of lipid accumulation during larval feeding is the same between starvation-selected populations and controls. To understand how the developmental delay is achieved we studied timing of gene expression during the 3rd instar. Genes associated with the 20-hydroxyecdysone (20E) pulse that results in puparium formation had delayed expression times. We rescued delayed larval development by feeding 20E to 3rd instar larvae, decreasing adult lipid stores, and further supporting a change in the timing of the 20E titer. We conclude that selection for adult starvation resistance has resulted in physiological changes in larvae that are mediated by 20E signaling. Supported by NSF award IOS-0719551 and NIH award 1R15GM100395.

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