Mechanistic basis for RNA aptamer-based induction of TetR.

The TetR aptamer induces TetR controlled gene expression, and represents an interesting tool for application in synthetic biology. We have analysed the mechanistic basis for RNA aptamer-based induction of TetR. The aptamer binds TetR with a high affinity in the order of 10(7)  M(-1), which is similar to operator DNA binding under the used ionic conditions.

An RNA aptamer that induces transcription.

We identified an RNA aptamer that induces TetR-controlled gene expression in Escherichia coli when expressed in the cell. The aptamer was found by a combined approach of in vitro selection for TetR binding and in vivo screening for TetR induction. The smallest active aptamer folds into a stem-loop with an internal loop interrupting the stem.