Mechanisms underlying microbial modulation of host behavior









1. Microbiome-dependent mechanisms in the regulation of host macronutrient preference.
The gut microbiome is recognized to influence host metabolic response to dietary consumption. For example, fecal transplantation studies in rodents have shown the donor microbiome can alter food consumption while determining the obese or lean phenotype of recipient hosts. The critical questions are how the gut microbiome actively regulates host feeding preference for specific nutrients, and to what extent does the microbiome contributes to variation in foraging behavior and food preferences? 
Using Drosophila, we recently discovered that foraging behavior and diet choices vary depending on the gut microbiome status (Current Biology and unpub. data). We are currently delineating the genetic and chemical mechanisms underlying these microbiome-mediated effects.

2. Sex differences in microbiome-mediated effects on behavior.
In sexually reproduced animals, males and females are distinct in their foraging motivation and reproductive investments. For example, in many oviparous insects, females make foraging decisions to fulfill both their own nutritional needs (feeding) as well as those of their offspring (oviposition). Females also allocate a large amount of energy and resources to oogenesis, requiring significant nutrient intake from the diet. These male- and female- specific nutritional needs are likely to drive sex-specific patterns of foraging and diet selection behaviors. Given the importance of the microbiome in nutrition and metabolism, we are investigating how sex - microbiome interactions could exert different behavior outcomes, such as foraging and food choices.