This article details two methods for separation and visualization of RNA under nondenaturing conditions, i.e., where the secondary structure of the molecules is left intact during electrophoresis. The first method describes electrophoresis in a 2% (w/v) agarose gel in a dilute, neutral phosphate buffer. The second deals with electrophoresis in a linear gradient of polyacrylamide based on the buffer system of Loening (1 ).
