We have engineered a riboregulator as the negative-sense strand of another riboregulator. This new RNA molecule performs the cellular function of titration of a functional molecule or trans-activation of gene expression.

We have followed a computational design approach with energetic and structural criteria to obtain the nucleotide sequence of a 5′ untranslated region responding to the new riboregulator.

We have engineered different regulatory circuits with trans-activating and anti-trans-activating small RNAs and characterized them at the population and single-cell levels.