Yeast volatiles double starvation survival in Drosophila.

Organisms make decisions based on the information they gather from their environment, the effects of which affect their fitness. Understanding how these interactions affect physiology may generate interventions that improve the length and quality of life. Here, we provide evidence that exposure to live yeast volatiles during starvation significantly extends survival, increases activity, and slows the rate of triacylglyceride (TAG) decline independent of canonical sensory perception. We demonstrate that ethanol (EtOH) is one of the active components in yeast volatiles that influences these phenotypes and that EtOH metabolites mediate dynamic mechanisms to promote Drosophila survival. Silencing R4d neurons reverses the ability of high EtOH concentrations to promote starvation survival, and their activation promotes EtOH metabolism. The transcription factor foxo promotes EtOH resistance, likely by protection from EtOH toxicity. Our results suggest that food-related cues recruit neural circuits and modulate stress signaling pathways to promote survival during starvation.