Feedback architectures to regulate flux of components in artificial gene networks

This paper focuses on the regulation of RNA production for in vitro synthetic gene networks. We consider the problem of matching the production rate of several RNA species concurrently transcribed to form RNA complexes. We design regulatory feedback loops based on two schemes: negative auto-regulation (which can minimize the potentially harmful amount of molecules not used to form products) and cross-activation (which can maximize the overall output flux). We analyze numerically the performance of these schemes: in both cases, transcription rate matching can be achieved through proper feedback constants; negative feedback is faster and maintains stability. A possible experimental implementation of a three and four genes negative feedback architecture is also numerically studied.