Essential Physiological Differences Characterize Short- and Long-Lived Strains of Drosophila melanogaster

Abstract

Aging is a multifactorial process which affects all animals. Aging as a result of damage accumulation is the most accepted explanation but the proximal causes remain to be elucidated. There is also evidence indicating that aging has an important genetic component. Animal species age at different rates and specific signaling pathways, such as insulin/insulin-like growth factor, can regulate life span of individuals within a species by reprogramming cells in response to environmental changes. Here, we use an unbiased approach to identify novel factors that regulate life span in Drosophila melanogaster. We compare the transcriptome and metabolome of two wild-type strains used widely in aging research: short-lived Dahomey and long-lived Oregon R flies. We found that Dahomey flies carry several traits associated with short-lived individuals and species such as increased lipoxidative stress, decreased mitochondrial gene expression, and increased Target of Rapamycin signaling. Dahomey flies also have upregulated octopamine signaling known to stimulate foraging behavior. Accordingly, we present evidence that increased foraging behavior, under laboratory conditions where nutrients are in excess increases damage generation and accelerates aging. In summary, we have identified several new pathways, which influence longevity highlighting the contribution and importance of the genetic component of aging.

Keywords: Aging; Drosophila; Lipidomics; Metabolomics; RNA sequencing.