Abstract:
Obesity is an increasing pandemic and is caused by multiple factors including genotype, psychological stress, and gut microbiota. Our project investigated the effects produced by microbiota community, acquired from the environment and horizontal transfer, on traits related to obesity. The study applied a novel approach of raising Drosophila melanogaster, from ten wild-derived genetic lines on naturally fermented peaches, preserving genuine microbial conditions. Larvae raised on the natural and standard lab diets were significantly different in every tested phenotype. Frozen peach food provided nutritional conditions similar to the natural ones and preserved key microbial taxa necessary for survival and development. On the peach diet, the presence of parental microbiota increased the weight and development rate. Larvae raised on each tested diet formed microbial communities distinct from each other. In addition, we evaluated the change in microbial communities and larvae phenotypes due to the high fat and high sugar diet modifications. We observed that presence of symbiotic microbiota often mitigated the effect that harmful dietary modifications produced on larvae and was crucial for Drosophila survival on high sugar peach diets. Although genotype of the host was the most influential factor shaping the microbiota community, several dominant microbial taxa were consistently associated with nutritional modifications across lab and peach diets. The effect that individual microbial taxa produced on the host varied significantly with changing environmental and genetic conditions.