Dietary Stimuli, Intestinal Bacteria and Peptide Hormones Regulate Female Defecation Rate.

Peptide hormones control gut motility, but the intestinal stimuli and the gene networks coordinating this trait remain poorly defined. Here, we customized an assay to quantify female defecation rate as a proxy of intestinal motility. We found that bacterial infection with the human opportunistic bacterial pathogen (strain PA14) increases defecation rate in wild-type female flies, and we identified specific bacteria of the fly microbiota able to increase defecation rate.