The heterotrimeric [corrected] G protein subunit G alpha i is present on mitochondria

Abstract

Receptors that signal through heterotrimeric [corrected] GTP binding (G) proteins mediate the majority of intercellular communication. Recent evidence suggests that receptors acting through G proteins also transfer signals across the nuclear membrane. Here we present cell fractionation and immunolabeling data showing that the heterotrimeric [corrected] G protein subunit Galphai is associated with mitochondria. This finding suggests that G protein receptor signaling may be a feature common to all membranes.