Live dissection and surface labeling of proteins in Drosophila embryos

This protocol presents methods for the specific detection of neuronal cell-surface receptors and secreted factors. These techniques allow visualization of surface pools of receptor proteins and also reveal the surface distribution of secreted cues. Live dissection of embryos to expose the ventral nerve cord is also described. This procedure can be used to improve the ability to detect signals from suboptimal antibodies, where conventional staining gives poor results.