Eosin whole-brain mount staining to analyze neurodegeneration in a fly model of Alzheimer's disease.

In the fly brain, neurodegeneration is detected by the presence of vacuoles using conventional hematoxylin and eosin (H&E) or phalloidin staining, which are lengthy and expensive processes. Here, we present a faster and cost-effective 2-day protocol to visualize vacuoles in a fly model of Alzheimer disease. We describe eosin staining in the whole-brain mount, followed by confocal microscopy and image analysis with an open source Fiji plugin. This protocol can be applied to visualize different modules in the fly brain.