Advances in promoter engineering: Novel applications and predefined transcriptional control

Synthetic biology continues to progress by relying on more robust tools for transcriptional control, of which promoters are the most fundamental component. Numerous studies have sought to characterize promoter function, determine principles to guide their engineering, and create promoters with stronger expression or tailored inducible control. In this review, we will summarize promoter architecture and highlight recent advances in the field, focusing on the novel applications of inducible promoter design and engineering towards metabolic engineering and cellular therapeutic development. Additionally, we will highlight how the expansion of new, machine learning techniques for modeling and engineering promoter sequences are enabling more accurate prediction of promoter characteristics. Graphical Abstract Lay Summary Promoter engineering encompasses the development of new promoters that exhibit properties that don't exist in native sequences, such as improved strength or unique inducibility. Novel promoters can be created by following various design paradigms and applying tools like machine learning. Promoter engineering has become an essential tool for many synthetic biology applications, ranging from metabolic engineering to cellular therapeutics.