Optimisation of macro- to micronutrient balance for larval growth on a holidic diet
Authors: Sebastian Sorge; Panayotis Pachnis; Vanessa Tixier; Alex Gould
Affiliation: The Francis Crick Institute, London
Keywords: c. nutrition; q. other (Diet)
The contributions of individual macro- and micronutrients to Drosophila phenotypes can be untangled using holidic diets. Currently available holidic diets are useful for studying adult nutrition and lifespan but larval growth and/or development are substantially slower than on standard yeast-based diets. We previously published a chemically-defined diet (CDD) related to other published holidic diets and with a similarly poor larval performance. We now describe semi-systematic improvements to our CDD that substantially speed up larval growth and development, close to values obtained with a yeast-based diet. Our results confirm that amino-acid composition influences developmental speed but we also find that the precise macro- to micro-nutrient balance is of similar importance. Several non-essential micronutrients contribute to larval developmental progression to surprising degrees and even small changes in the nutrient balance can substantially perturb development. Together, these CDD studies help to define a narrow window of macro-to-micronutrient balance that is optimal for larval development. As a proof-of-principle, we apply the optimised CDD to larval stable isotope tracing experiments, determining the sugar carbon contribution to hemolymph polar metabolites and to de-novo synthesized fatty acids.