Many studies have addressed the effects of adult diet on gene expression in Drosophila melanogaster, however, little is known about how developmental diet influences adult gene expression, and how this interacts with adult dietary conditions. We found that developmental and adult diet exert largely independent effects on gene expression, with the effect of adult diet being considerably larger.We did find effects of developmental diet on the transcriptome that persist into middle and old-age. Most of the genes affected show no correlation with the observed phenotypic effects of larval diet on lifespan, however, in each sex we identified a cluster of ribosome, transcription, and translation-related genes whose expression was altered across the lifespan and negatively correlated with lifespan.
We raised flies as larvae on three different diets and switched them across these same diets as adults, using a fully factorial design (3 larval * 3 adult diets = 9 treatments in total). We measured gene expression in both sexes at 1 day post-eclosion, middle-age (10% cohort mortality) and old-age (90% cohort mortality).