Removing RRNA from Deproteinized, Phenol-extracted Total RNA by Enzymatic Digestion

Ribosomal RNAs (28S, 18S, 5.8S, and 5S rRNAs) comprise the vast majority of total cellular RNAs (>95%). When other RNAs are to be analyzed, it is very advantageous to remove the rRNA species. The best way to eliminate rRNA "contamination" is to pellet subunits before deproteinization. When this is not possible, certain RNAs can be separated from bulk rRNA after extraction. This protocol describes enzymatic digestion to remove rRNAs from deproteinized, phenol-extracted total RNA.