A dynamic riboregulator design with a programmable all-or-nothing response

Riboregulators represent an important class of genetic regulatory devices whose behavior is programmable by specification of the underlying nucleic acid sequence. Both natural and synthetic riboregulators are often modeled as static devices that activate or repress potential RNA binding sites. Individual riboregulators are thereby functionally similar to linear gains found in electrical systems. While in silico design tools are developed to maximize their in vivo performance, design of dynamic behavior has yet to be considered. Herein a simple riboregulator design is proposed that appends programmable dynamic behavior to existing riboswitches. The resulting device is shown to produce an all-or-nothing response. Simple design rules for this device are derived.