Engineered riboswitches control gene expression by small molecules.

B Suess

doi:10.1042/bst0330474

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Engineered riboswitches control gene expression by small molecules.

B Suess

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Abstract

We have developed conditional gene expression systems based on engineered small-molecule-binding riboswitches. Tetracycline-dependent regulation can be imposed on an mRNA in yeast by inserting an aptamer in its 5'-untranslated region. Biochemical and genetic analyses determined that binding of the ligand tetracycline leads to a pseudoknot-like linkage within the aptamer structure, thereby inhibiting the initial steps of translation. A second translational control element was designed by combining a theophylline aptamer with a communication module for which a 1 nt slipping mechanism had been proposed. This structural element was inserted close to the bacterial ribosomal binding site at a position just interfering with translation in the non-ligand-bound form. Addition of the ligand then shifts the inhibitory element to a distance that permits efficient translation.

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B Suess. 2005. Engineered riboswitches control gene expression by small molecules.. https://doi.org/10.1042/bst0330474

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