Shaulov, L. & Harel, A. Structure 20, 407–413 (2012).

The nuclear pore is a complex structure that is intimately connected with the organization of information in the cell. Field emission scanning electron microscopy (FESEM) can provide high-resolution, three-dimensional images of the pore surface, but the harsh treatment of nuclear membrane preparations precludes the imaging of pores in their native state. Shaulov & Harel optimize FESEM preparations by anchoring chromatin to silicon chips before applying Xenopus laevis egg extracts in a classic nuclear membrane reconstitution system. They also avoid detergents by repeated hypotonic treatment and pipetting of mammalian cells to expose the outer nuclear surface. Images from these preparations showed expanses of intact pores and membrane, robustness to antibody labeling and intermediate stages of pore assembly visualized using an assembly inhibitor.