Nutritional stress in larvae induces adaptive responses that transcend generations in males of a model insect

The ability of organisms to cope with poor quality nutrition is essential
for their persistence. For species with a short generation time, the
nutritional environments can transcend generations, making it
beneficial for adults to prime their offspring to particular diets.
However, our understanding of adaptive generational responses,
including those to diet quality, are still very limited. Here, we used the
vinegar fly, Drosophila melanogaster, to investigate whether females
developing as larvae on a nutritionally poor diet produce offspring
that are primed for nutrient deficiencies in the following generations.
We found that females developed on low-quality diets produced
offspring that, on similarly low-quality diets, had both increased
egg-to-adult viability and starvation tolerance compared with offspring
of females experiencing a nutrient-rich diet. When testing the
persistence of such generational priming, we found that just one
generation of high-quality diet is sufficient to erase the signal of
priming. A global transcriptomic profile analysis on male offspring
suggests that the observed phenotypic priming is not a constitutive
transcriptomic adjustment of adults; instead, offspring are probably
primed as larvae, enabling them to initiate an adaptive response as
adults when exposed to low-quality diets. Our results support that
generational priming is an important adaptive mechanism that
enables organisms to cope with transient nutritional fluctuations.