Oxidative Stress Resistance of the Extended Longevity Phenotype of Drosophila Under Paraquat Exposure Is Heritable: Influence of Maternal Genotype on the Offspring

Resistance to oxidative stress is a key determinant of extended longevity in Drosophila melanogaster . Here, we investigated the transgenerational inheritance of paraquat-induced oxidative stress resistance using reciprocal crosses between normal lifespan (NLS) and long lifespan (LLS) lines of D. melanogaster , examining survival, locomotor performance, and a biochemical antioxidant defense markers including reactive oxygen species (ROS), lipid peroxidation (LPO), superoxide dismutase (total SOD and MnSOD), catalase, reduced glutathione, and acetylcholinesterase activity, across parental, F ₁ , and F ₂ generations. The results showed that long-lived flies were more resistant to paraquat toxicity than NLS flies, and that this increased resistance to oxidative stress was more pronounced in females than in males across all tested generations. A pronounced maternal effect is evident from the results of the cross between NLS male and LLS females (N♂ × L♀), as all parameters (mortality, locomotor capacity, antioxidants) of their offspring consistently showed lower mortality, superior locomotor performance, and stronger antioxidant defenses compared to offspring from NLS mothers, across F ₁ and F ₂ generations. Variance partitioning between parental and offspring generations showed a strong maternal effect on ROS, LPO, SOD, and MnSOD levels. Offspring from LLS mothers had elevated MnSOD levels, a sign of mitochondrial inheritance. Heritability of survival against paraquat toxicity declined in subsequent generations, whereas behavior and biochemical markers continued to express strong transgenerational effects. Heterosis in N♂ × L♀ F ₁ flies for the oxidative stress resistance trait exceeded the mid-parent value. The oxidative stress resistance trait, a major longevity-affecting factor in Drosophila , is strongly under heritable control and largely additive. In addition, maternal effect influences this trait in subsequent generations, thus playing a persistent and central role.