Copper cells and stomach acid secretion in the Drosophila midgut

Copper cells in the Drosophila midgut were originally named for their ability to accumulate dietary copper. Recent studies have uncovered a number of intriguing similarities between copper cells and the acid-producing gastric parietal cells of the mammalian stomach. In addition to their shared roles in stomach acidification, they share a peculiar invaginated morphology in which the apical cell surface is buried deep within the cytoplasm. These shared properties of morphology and function portend the identification of shared molecular mechanisms that account for their specialized roles in digestive physiology.