Riboregulator elements as tools to engineer gene expression in cyanobacteria

Cyanobacteria are an ideal host for biofuel production. Although efforts have been made to genetically engineer cyanobacteria for efficient production of biofuels and other important chemicals, the tools that can be applied to cyanobacteria are still limited. A new gene regulation tool, riboregulator, has been examined for application in cyanobacteria. A riboregulator is a nature-inspired RNA tool, which is composed of two artificially designed RNA fragments. Owing to its high specificity and efficacy, it is suitable for metabolic engineering in cyanobacteria, and several studies have been done to optimize and improve the function of the riboregulator. In this review, we focus on the recent improvements made to riboregulators and compare them with other RNA-mediated gene regulation tools developed in cyanobacteria to investigate future applications of riboregulators.