Meeting Abstract
Plasticity of size and metabolic activity of organs might drive allocation of resources to different functions, such as self-maintenance, growth, storage and reproduction. Plasticity, in turn, might be the result of changes that occur in individual cells, driven by environmental cues. The nutritional status of the cells can alter metabolic pathways via post-translational modifications, like lysine acetylation. Sirtuins, a family of protein de-acetylases, have been related with the expression of changes in the metabolic phenotype. We hypothesized that plasticity in the metabolic activity of organs will be mediated by sirtuins. We measured metabolic rates, phenotypic plasticity of organ size, and patterns of protein acetylation in different tissues, in females of the viviparous cockroach Diploptera punctata. We used adult virgin females exposed to diet switches: (1) from low quality (LQ) to high-quality (HQ), then back to LQ, in periods of 30 days; and (2) from HQ to LQ, then to HQ again, in periods of 30 days. We found differences in the pattern of acetylation between diet groups, but also between organs of females. Females fed a LQ diet showed more intense acetylation of proteins in their gut than females fed with a HQ diet, consistent with a lower activity of the organ. Overall, these results suggest tissue-specific patterns of acetylation in response to dietary regimes, patterns that are consistent with the changes observed in whole-organism metabolic rates when diets were switched. Our results also suggest that the expression of phenotypic plasticity in organ size and activity is associated with changes at the molecular level.
