Single-Neuron Labeling Using the Genetic MARCM Method

INTRODUCTIONOur brain is composed of hundreds of billions of neurons, each of which has an elaborate shape and a complex pattern of connections. To untangle this complexity, it is often useful to visualize one neuron at a time. This protocol describes single-neuron labeling using the MARCM system (Mosaic Analysis with a Repressible Cell Marker). The system was developed in Drosophila, but could, in principle, also work in other genetic model organisms such as Caenorhabditis elegans, zebrafish, or mice.