Microelectrode-Mediated FM Dye Loading and Unloading in <em>Drosophila</em> Larvae Nerve Cells

Source: Kopke, D. L., et al., FM dye cycling at the synapse: comparing high potassium depolarization, electrical and channelrhodopsin stimulation. J. Vis. Exp. (2018) In this video, Drosophila larvae nerve fibers are immersed in FM dye, which binds to cell membrane lipids. Suction microelectrode and electrical pulses stimulate the endocytosis process, incorporating the FM dye into newly formed endocytic vesicles. This method, which visualizes presynaptic stages of neurotransmission, is useful for studying synaptic function and neurotransmitter release.