Between Immunity, Metabolism, and Development: A story of a Fly Gut!

In addition to its role in initiating immune response in the body, the innate immune system seems to also play a critical role in maintaining homeostatic balance in the gut epithelium. Our recent studies in the Drosophila melanogaster fruit fly model suggest that different innate immune pathways contribute to this homeostatic balance through activating the transcription of genes encoding antimicrobial peptides. We provide evidence that several metabolic parameters are altered in immune deficient flies. We also highlight a role of the gut flora, particularly through its short chain fatty acid, in contributing to this metabolic balance. Interestingly, our data suggest that impaired immunity and metabolic alteration, in turn, exhibit an effect on host development. Collectively, these findings provide evidence that innate immune pathways not only provide the first line of defense against infection but also contribute to host metabolism and developmen