In situ localization of specific RNAs in developing fruit bodies of the basidiomyceteSchizophyllum commune

cDNA clones representing mRNAs abundantly expressed during fruiting ofSchizophyllum commune were used to detect the cellular localization of these mRNAs in freeze-microtome sections of developing fruit bodies. An 18 S rRNA clone was isolated and used as a probe for total RNA. Both RNA and DNA probes with different labels were found suitable but the procedure finally adopted involvedin situ hybridization with nick-translated biotinylated DNA probes. To permit the probes to permeate the cell walls it was necessary to treat the sections with RNasedepletedTrichoderma harzianum wall-lytic enzymes before hybridization. Hybridization at different developmental stages showed that the specific mRNAs were abundantly expressed in specific areas of the fruit bodies.