Meeting Abstract

17-1  Monday, Jan. 4 10:00  The effect of TOR signaling on nitrogen stable isotope fractionation ROSENCRANS, WM*; HATCH, KA; BRUMMEL, T; Colgate University; Long Island University Post; Long Island University Post wrosencrans@colgate.edu

Stable Isotope analysis (SIA) is used to non-invasively determine the nutritional status or trophic level of animal populations. However, the molecular mechanisms that affect the fractionation of stable isotopes are poorly understood. The focus of this study is to investigate the relationship between δ¹⁵N fractionation in animal tissue and the Target of Rapamycin (dTOR) signaling pathway. We subjected, Drosophila melanogaster to dietary, pharmacological, and genetic manipulations that alter dTOR activity. The δ¹⁵N of these flies were then analyzed. We found that manipulations that lowered dTOR signaling (e.g. protein restriction, ethanol, rapamycin, and the inaE^EP1011 mutation) raised δ¹⁵N approximately 1per mil while enhancing TOR signaling via the inaE^KG08585 mutation genetically prevented the increase in δ¹⁵N the associated with dietary restriction (p < 0.05). The dTOR pathway activity helps explain variations and anomalies in expected trophic level shifts. Furthermore the δ¹⁵N assay may prove useful in analyzing TOR activity, which has been implicated in aging, cancer, Alzheimer’s, and various metabolic diseases.