(12d) Developing RNA-Based Genetic Control Systems to Quantitatively-Program Functions in Engineered Metabolic Pathways

Authors: 
Carothers, J., University of Washington


Naturally-occurring metabolic systems have evolved control circuitry that minimizes the accumulation of toxic intermediates and maintains homeostasis. At present, the process of engineering even rudimentary control circuitry for synthetic biological systems remains very difficult. We have successfully formulated design-driven approaches that use mechanistic modeling and kinetic RNA folding simulations to engineer RNA-regulated genetic devices with quantitatively-predictable activities that can control gene expression in metabolic pathways producing industrial chemicals in E. coli (Carothers et al. & Keasling. Science 2011). We have also demonstrated that models and simulation tools can be used to inform the design of microbial dynamic sensor-regulator systems (DSRS) engineered to produce fatty acid-based chemicals and fuels (Zhang, Carothers, & Keasling. Nature Biotech. 2012). We are currently designing RNA-based systems to solve canonical control problems in a 15 gene pathway engineered to produce substituted styrenes, components of polymer composites with optical and mechanical properties favorable for advanced applications in photonics, photolithography and biomedicine. Here, I will present these results and discuss the potential for using the conceptual and experimental frameworks that we have established to create full-fledged design platforms.