Subcellular Location of mRNA by Electron Microscope Hybridization Histochemistry

Hybridization histochemistry can be used at the light microscope level to determine the cellular site of gene expression in heterogeneous cell populations in tissue sections. However, the question often arises as to exactly which cell in a heterogeneous population is labeled and how this cell differs from unlabeled neighboring cells. The region of a cell in which mRNA transcripts of a particular gene are located is also of interest, particularly in polarized cells, such as neurons or epithelium. The adaptation of hybridization histochemistry to the electron microscope (EM) enables these questions to be answered and can also provide useful information about subcellular processes.