Transcriptomic analysis of symbiotic organs in Plautia stali infected with Escherichia coli

The brown-winged stink bug, Plautia stali, possesses a specialized symbiotic organ in the posterior midgut and depends on essential intestinal symbiotic bacteria for survival. This insect-associated bacterial mutualist exhibits pronounced genome reduction, specialized metabolic capabilities, and uncultivability; however, its evolutionary origin remains unclear. Notably, infection with a methionine-overproducing Escherichia coli strain enhances the fitness of the stink bug, thereby providing a tractable experimental system for investigating the early evolutionary processes underlying the establishment of symbiotic mutualism.