Interactions between injury, stress resistance, reproduction, and aging in Drosophila melanogaster

Abstract

SummaryAn important aspect of the aging process in Drosophila melanogaster is the natural loss of antennae, legs, bristles, and parts of wings with age. These injuries lead to a loss of hemolymph, which contains water and nutrients. Stress-resistant lines of D. melanogaster are sometimes longer-lived than the populations from which they are derived. One hypothesis tested here is that increased stress resistance fosters longevity because it allows fruit flies to cope with the loss of hemolymph due to injury to the aging fly. We tested the effects of surgically induced injury on the aging and reproduction of five replicate populations. We then tested the effects of injury on populations that had been selected for different levels of stress resistance and on control populations. Injury affected aging more in males than in females, in part because of a counter-balancing reduction in female reproduction brought about by injury. More specifically, injury reduced female fecundity and male virility. Injury significantly reduced the starvation resistance in some groups of flies, but not in others. These findings undermine any simple interpretation of the interactions between injury, reproduction, and aging based on stress resistance. But they do indicate the existence of significant interactions between these biological processes, interactions that should be resolved in greater mechanistic detail than has been managed here. §To whom all correspondence and queries should be addressed:

Decreased mitochondrial superoxide levels and enhanced protection against paraquat inDrosophilamelanogastersupplemented withRhodiola rosea

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Mortality from desiccation contributes to a genotype-by-temperature interaction for cold survival inDrosophila melanogaster

“…In D. melanogaster, less desiccation-resistant males have lower mating success in arid environments (Gefen and Gibbs, 2009). Yet, female fecundity is not lowered by desiccation (Albers and Bradley, 2006;Sepulveda et al, 2008), suggesting that the physiological consequences of bouts of desiccating cold exposure may be sexspecific. Thus, the selection pressure experienced by flies at temperatures near 0°C may increase desiccation resistance due to the correlated effects of dehydration on reproductive success, regardless of whether mortality is due to dehydration.…”

The molecular characterization of antioxidant enzyme genes in Helicoverpa armigera adults and their involvement in response to ultraviolet-A stress

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