Lipid reconstitution and recording of recombinant ion channels

Ion channels are membrane proteins that facilitate passive ion movements down the electrochemical gradients across biological membranes. They regulate a wide range of important physiological functions, from neuronal excitation, muscle contraction, substance absorption in epithelial tissues, to innate immunity. In recent years, the membrane transport field has seen tremendous advances in membrane protein purification and structural determination. This paves the way for investigators to reconstitute ion channels into biochemically defined lipid systems free of other biological constituents and to study channel functions within a structural context. The goal of this chapter is to guide readers through the process of producing proteoliposomes, designing liposome assays for initial characterization of channel function, and performing electrical recordings for in-depth mechanistic investigation.