A simple method for isolation of intact RNA from dried polyacrylamide gels.

We have developed a simple, rapid method to isolate intact radioactively labelled RNA (either with ^ P or S) from dried polyacrylamide gels on Whatman paper, thus allowing its further investigation even after several months (in the case of a Slabel) of handling the gels without any protection, e.g. from RNases. The isolated RNA molecules are still biologically active, since we could demonstrate the catalytic activity of an isolated selfsplicing group II intron RNA from yeast mitochondria. A ^P-radioactively labelled RNA of 1031 nt harbouring a selfsplicing intron was electrophoresed on two lanes on a denaturing 5% polyacrylamide gel. One of the lanes was dried on Whatman paper at 80°C under vacuum after electrophoresis, the second lane was used for the usual isolation from a wet gel as a control (Peattie, 1979). The position of the RNA in the gel was determined by autoradiography.