A subset of enteroendocrine cells is activated by amino acids in the Drosophila midgut.

The intestine is involved in digestion and absorption, as well as the regulation of metabolism upon sensation of the internal intestinal environment. Enteroendocrine cells are thought to mediate these internal intestinal chemosensory functions. Using the CaLexA (calcium-dependent nuclear import of LexA) method, we examined the enteroendocrine cell populations that are activated when flies are subjected to various dietary conditions such as starvation, sugar, high fat, protein, or pathogen exposure. We find that a specific subpopulation of enteroendocrine cells in the posterior midgut which express Dh31 and tachykinin are activated by the presence of proteins and amino acids.