SELECTION ON STRESS RESISTANCE INCREASES LONGEVITY IN DROSOPHILA MELANOGASTER

Abstract

--Tests for the causal involvement of specific physiological mechanisms in the control of aging require evidence that these mechanisms can be used to increase longevity or reproductive lifespan. Selection for later reproduction in Drosophila has been shown to lead to increased longevity, as well as increased resistance to starvation and desiccation stresses. Selection for increased resistance to starvation and desiccation in Drosophila melanogaster is here shown to lead to increased longevity, indicating that alleles that increase stress resistance also may increase longevity. The responses of desiccation and starvation resistance to selection are partly independent of each other, indicating a multiplicity of physiological mechanisms involved in selectively postponed aging, and thus aging in general.

Improved functional abilities of the life-extended Drosophila mutant Methuselah are reversed at old age to below control levels

“…These include screening genetic mutants for longevity phenotypes (Lin et al 1998), overexpression of genes known to enhance antioxidant defense mechanisms (Parkes et al 1998), generational selection studies (Rose et al 1992), and environmental strategies such as drug consumption (e.g., 4-phenylbutyrate; PBA; Kang et al 2002) or caloric restriction (Clancy et al 2002;Mair et al 2003). It is becoming increasingly clear that different genetic and environmental strategies for life extension lead to different patterns of gerontological decline in functional abilities of Drosophila (e.g., flight, locomotion, visuo-motor coordination, memory, and learning).…”

“…The wild-type Drosophila has a maximum lifespan of approximately 1.5 to 2 months, aauditory, and memory), and a high homology of genes to other species including mammals (Rose et al 1992;Curtsinger et al 1995;Osiewacz 1997;Parkes et al 1998;Butler 1999;Phillips et al 2000). Fortini et al (2000), for example, have reported that approximately 65 % of human disease genes are conserved in Drosophila (187 of 287 examined).…”

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

“…In experiment 6 we used the following five-fold replicated stocks: "D" selected for desiccation resistance; "C" selected for starvation resistance, and "CO" as controls (Rose et al, 1992). The D, C, and CO lines of flies were derived from the long-lived O populations in 1989.…”

“…Specifically, laboratory selection for postponed reproduction in D. melanogaster has produced populations that have postponed aging Rose and Charlesworth, 1980) and lowered reproduction Service, 1989Service, , 1993Service and Fales, 1993;Service and Vossbrink, 1996). Such fruit flies sometimes show a trade-off between stress resistance and early reproduction (Chippindale et al, 1993;Leroi et al, 1994;Rose et al, 1992;Service and Rose, 1985), suggesting a trade-off of energetic reserves between survival and reproduction (Chippindale et al, 1993;Chippindale, 1994;Graves et al, 1992). Furthermore, selection for stress resistance has been shown to increase longevity (Rose et al, 1992;Rose et al, 2004), suggesting that stress resistance is a causal contributor to longevity and postponed senescence.…”

“…Such fruit flies sometimes show a trade-off between stress resistance and early reproduction (Chippindale et al, 1993;Leroi et al, 1994;Rose et al, 1992;Service and Rose, 1985), suggesting a trade-off of energetic reserves between survival and reproduction (Chippindale et al, 1993;Chippindale, 1994;Graves et al, 1992). Furthermore, selection for stress resistance has been shown to increase longevity (Rose et al, 1992;Rose et al, 2004), suggesting that stress resistance is a causal contributor to longevity and postponed senescence.…”