Development of High Pressure Freezing and Correlative Light/Electron Microscopy for Drosophila Larvae

We are interested in the mechanisms by which cells generate and maintain their complex architectures. A major structural element in cells are lipid membranes, which define both the external cell shape as well as forming subcellular compartments, such as organelles. Transmission electron microscopy (TEM) remains a method of choice for examine cell ultrastructure, particularly for examining cellular membranes. Fixation methods that maintain membranes in their native states are thus critical for examining cells using TEM. One such method is high pressure freezing (HPF), in which rapid freezing under high pressures is used to prevent the formation of water ice crystals that otherwise disrupt cellular architecture. 1