Trans-generational effect of protein restricted diet on adult body and wing size of Drosophila melanogaster

Protein restriction (PR) has established feasible trade-offs in Drosophila melanogaster to understand lifespan or ageing in a nutritionally challenged environment. However, the phenotypes of body size, weight and wing length respond according to factors such as flies' genotype, environmental exposure and parental diet, and hence their understanding is essential. Here, we demonstrate the effect of long-term PR diet on body size, weight, normal and dry wing length of flies subjected to PR50 and PR70 (50% and 70% protein content present in control food, respectively) for 20 generations from the pre-adult stage. We found that PR-fed flies have lower body weight, relative water content (in males), unaltered (PR50%) and higher (PR70%) relative fat content in males, smaller normal and dry body size when compared with control and generations 1 and 2. Interestingly, the wing size and pupal size of PR flies are smaller and showed significant effects on diet and generation. Thus, these traits are sex and generation dependent along with a diet interaction, which is capable of modulating these results variably. Taken together, the trans-generational effect of PR on fitness and fitness-related traits might be helpful to understand the underpinning mechanisms of evolution and ageing in fruit flies D. melanogaster.

Automated summary

This study investigated the effects of long-term protein restriction diet on body size, weight, and wing length in fruit flies. The results showed that flies on a protein-restricted diet had lower body weight and relative water content, unchanged or higher relative fat content, and smaller normal and dry wing length. Furthermore, protein restriction also significantly affected wing size and pupal size, and these effects were influenced by diet and generation.