Detection of AKR MuLV-specific RNA in AKR mouse cells by in situ hybridization

Conditions for the detection of complex RNA sequences by in situ hybridization have been investigated by using a single-stranded 3H-cDNA probe complementary to the AKR MuLV genome and in vitro cultured AKR mouse cells which spontaneously produce AKR MuLV. It is shown that fixation with glutaraldehyde at low concentration allows cellular RNA to be sufficiently well retained during the annealing process and that stringent conditions in situ can be maintained by means of formamide. Some conditions which promote atypical and non-specific binding of the probe have been identified.