The roles of V-type H+-ATPase and Na+/K+-ATPase in energizing K+ and H+ transport in larval Drosophila gut epithelia

We analyzed V-type H⁺-ATPase (VA) and Na⁺/K⁺-ATPase (NKA) along the caeca and midgut of third instar Drosophila larvae using immunohistochemistry and ATPase activity assays. Corresponding H⁺ and K⁺ fluxes were characterized using the Scanning Ion-Selective Electrode Technique (SIET), and the roles of transport ATPases in energizing ion transport across the larval gut were investigated by basal application of bafilomycin, a VA inhibitor, and …