In the Rakoff-Nahoum lab, I will explore the mechanisms that allow a host organism to monitor the quality of its diet and the function of its microbiome. The presence of beneficial bacteria in the gut plays an important role in the health of an organism. We have found that certain intestinal bacteria break down complex polysaccharides and liberate simple sugars—which serve as food for other members of the microbial community. In preliminary studies, I have found that these liberated sugars can alter intestinal homeostasis in mice. Using methods in microbial and molecular genetics and computational and evolutionary biology, I will assess how different polysaccharides alter the gene activation profile of the mouse intestine and how these liberated sugars impact intestinal injury and repair. Our work stands to define a new mechanism of diet-microbiome-host interactions that may be applied for novel strategies for therapeutics in human health.