19-BBSRC-NSF/BIO Characterizing efficiency and limitations of RNA regulators to achieve robust dynamic behaviours

Synthetic biology has made it possible to use cells to operate as microscale factories, energy sources, and even computers. However, the introduction of DNA circuits into cells can cause the cells to be stressed, something named as burden. Circuits that are poorly tunable, and non-native to the host often causes undesired cross-interactions and unpredictable responses, and reliable engineering of cells remains a challenge.

In particular, the expression of exogenous pathways triggers physiological changes in the host, usually leading to decreased growth due to consumption of cellular resources, a phenomenon known as cellular burden.

These challenges could be solved using RNA-based regulators of gene expression. These are systems which require transcription to occur but not translation, as no protein needs to be produced. The RNA acts as a regulatory molecule that can impact on the behaviour of the circuit in the cells. RNA circuits are programmable regulatory platform that imposes a lower burden on the host.

Yet, little attention has been dedicated to systematically tuning the behaviour of RNA regulators. This project aims at screening and tuning two classes of RNA regulators. The regulators will then be employed as rapid, tunable components to better understand burden in bacteria.

With improved knowledge of burden, we will modify bacteria to achieve better bioproduction of molecules of interest. Mathematical modelling will help our work by assisting the choice of experiments and circuits to be adopted.