Super-resolution microscopy is a very powerful tool to investigate fine cellular structures and molecular arrangements in biological systems. For instance, stimulated emission depletion (STED) microscopy has been successfully used in recent years to investigate the arrangement and colocalization of different protein species in cells in culture and on the surface of specimens. However, because of its extreme sensitivity to light scattering, super-resolution imaging deep inside tissues remains a challenge. Here, we describe the preparation of thin slices from the fruit fly (Drosophila melanogaster) brain, subsequent immunolabeling and imaging with STED microscopy. This protocol allowed us to image small dendritic branches from neurons located deep in the fly brain with improved resolution compared with conventional light microscopy.
Keywords: Brain slice; Cryostat sectioning; Drosophila melanogaster; Immunofluorescence; STED.