Fig. 8. Molecular mechanism of photo-induced depolarization with the initiation and repolarization of TC1. TC1 causes charge separation by photostimulation (hν). cpHDL-TC1 is generated by inserting TC1 into cpHDL and is properly introduced into the cell membrane of PC12 cells before measurement. The resting membrane potential shows a membrane potential of -50 mV due to the activity of the K channel. There is no change in resting membrane potential even in cells with cpHDL-TC1 inserted. Subsequently, Photo-activated TC1 causes depolarization by generating PACS (photo-activated CS molecule induced) current in parallel with the suppression of the K⁺ current via the effect on lipid component (dark blue). This depolarization persists for a time, but the internalization of TC1 from the membrane and insertion of new lipids into the cell membrane, resulting in the restoration of K_V to normal activity and eliminating PACS currents, take place slowly.