Transcriptional Oscillators

This chapter focuses on a class of cell-free synthetic biological systems - "genelet circuits" - that are entirely based on in vitro gene transcription. The most attractive feature of in vitro transcription circuits is that, in principle, all of their molecular components are known. The chapter discusses the properties of a simple dynamical feedback system that captures many of the features of a two-node transcriptional oscillator. It then demonstrates how techniques originally developed for control theory can be applied to study transcription systems. Next, the chapter discusses the actual experimental implementation of the oscillator, and provides an overview of the main experimental findings. It concludes with a brief discussion of a more thorough model description of the two-node transcription oscillator, and also considers the effect of molecular stochasticity that arises when working with small molecule numbers.