Final Report Summary - BRAINGUTTALK (Brain-gut interactions in Drosophila melanogaster)
Our gastrointestinal tract is populated by millions of nerve cells, yet we know relatively little about what all these nerve cells do. Fruit flies have guts and nerve cells which, unlike ours or those of other animals, are relatively easy to manipulate by turning their genes on or off. We have used flies to explore how and why the nerve cells of the gut communicate with other organs. We have found that some of these nerve cells play key roles in adaptations to malnutrition; they release chemicals to change the size of the tracheal system that, like our blood vessels, delivers oxygen to the intestine. It will now be of interest to investigate whether communication between the nerve cells and blood vessels of our digestive system plays similar roles in malnutrition or obesity. More recently, we have also explored how the intestine itself reacts to challenges such as malnutrition or reproduction, and have identified an important gene that senses nutrients in intestinal cells. Unexpectedly, our work has also revealed that the cells that make up the intestinal lining are actually very different between males and females. Being female help these cells make the intestine grow during reproduction, maximising reproductive output, but also renders them more vulnerable to genetically induced tumours. It will be of interest to explore whether similar changes occur in humans during pregnancy and lactation, and whether they might contribute to fecundity, post-pregnancy weight retention and/or sex biases in gastrointestinal disease burden.