Method for blot-hybridization analysis of mRNA molecules from Bacillus subtilis

By modifying hybridization techniques which are currently available to analyze RNA molecules we have developed a sensitive and reproducible method for 'Northern' analysis of RNA from Bacillus subtilis. The use of a thin (1 mm) vertical 2% agarose-6% formaldehyde gel seems to allow more efficient transfer and higher resolution of RNA upon hybridization analysis than does the use of thicker horizontal slab gels. Our improved hybridization method results in greatly reduced background upon autoradiography regardless of whether or not 32P-labelled nick-translated probes or probes synthesized on M13 vectors were purified from the unincorporated radionucleotides.