Figure 2

G _i2α ribozyme. A: Ribozyme in vitro cleavage activity. A PhosphorImager (Molecular Dynamics, Sunnyvale, CA, USA) printout of a 15 % polyacrylamide gel with 7 M urea. The 5'-end-labelled RNA substrate (200 nM) was incubated with the ribozyme (75 nM) in reaction buffer as described in Materials and Methods. 10 μl samples were taken at the indicated time, added to 5 μl quenching solution and then analysed by electrophoresis. The arrow indicates cleavage products. B: Ribozyme uptake in cultured hepatocytes. Hepatocytes were transfected with 5'-FITC-labelled ribozyme for 30 h. Following washing with phosphate-buffered saline (PBS), cells were analysed by fluorescence microscopy.