A simple technique for the visualization of whole mount cytoskeletons with transmission electron microscopy

Examination of whole mount cells in the transmission electron microscope has been useful in studies of cellular architecture. The common technique is to grow cells directly on formvar-coated, gold grids for direct observation through a cell. We report a technique for obtaining whole mount preparations which requires neither fragile formvar films nor expensive, gold grids. Cells are grown on palladium-coated coverslips and processed for electron microscopy. The cells and the palladium substrate are separated from the coverslip. The cell-palladium complex is then picked up on copper grids as in thin section processing. We compare images of the cytoskeleton using our technique with images using previously described techniques and present preliminary observations of contracting cell models. Such contractions would tear formvar films if attempted on cells grown in the conventional manner for whole mount examination. Our technique allows cells to contract without tearing the underlying substrate.