FIG. 2.

Autocatalytic processing of the ribozyme-aptamer-ribozyme transcripts in vitro. Denaturing polyacrylamide gel electrophoresis shows the products of T3 RNA polymerase-mediated in vitro transcription of ribozyme-aptamer-ribozyme constructs. The 5′ and 3′ flanking ribozyme fragments (118 and 193 nucleotides, respectively) released by self-cleavage are indicated. The sizes of the liberated aptamer fragments range from 66 to 101 nucleotides (arrows). The empty vector releases a 44-nucleotide fragment containing just the flanking ribozymes and the linker sequence containing the restriction sites (rightmost lane).