Probing the spatial organization of nucleic acids within cells by nonisotopic in situ hybridization
In situ hybridization is a powerful experimental approach that directly couples molecular and cytological information in a visual context. Advances in hybridization procedures over recent years, coupled with previously described non-isotopic labelling methods developed in a number of laboratories, now provide a way to detect nucleic acids within cells with a high degree of resolution and sensitivity. Adaptations of this technology allow either DNA or RNA to be detected and visualized either with the light microscope, using fluorescence or colorimetric methods, or with the electron microscope using antibodies conjugated to gold or peroxidase. The potential applications of this technology are relevant to numerous areas of biomedical research and range from the more straightforward study of differential gene expression in single cells within a population to the precise localization of individual genes or RNAs within the cytoplasm or nucleus of a cell.