A Novel Method to Image Macropinocytosis in Vivo .

Here we described an experimental protocol for in vivo imaging of macropinocytosis and subsequent intracellular events. By microinjection, we delivered fluorescence dextrans together with or without ATP gamma S into transparent Drosophila melanogaster embryos. Using a confocal microscope for live imaging, we monitored the generation of dextran-positive macropinosomes and subsequent intracellular events. Our protocol provides a continent and reliable way for investigating macropinocytosis and its underlying mechanisms, especially when combined with genetic strategies.