KCNJ2 and type 1 diabetes mellitus: To create a type 1 diabetes-like state (Fig. 2A), we silenced insulin-producing cells (IPCs) by expressing an inward rectifying potassium channel (Kir2.1) using the dilp2 (Ilp2)-Gal4 driver, which is specific for IPCs (Rulifson et al., 2002).