[Synthetic promoters: theory, design, and prospects]

Synthetic promoters are novel promoters artificially designed and do not exist in nature. They can initiate the expression of target genes with specific regulatory modes, offering advantages such as high expression efficiency, precise regulation, and modularity. These features endow synthetic promoters with significant application potential in fields such as industrial production, environmental monitoring, and disease diagnosis and treatment. This paper reviews the basic structures, functions, and classification of promoters, discusses various regulatory elements that influence promoter functions, including enhancers, signal response elements, and transcription factors. Additionally, the conventional and deep learning-based strategies for designing synthetic promoters are summarized. Finally, the theoretical significance of synthetic promoters is emphasized, which is followed by an overview of their current applications, along with a rational discussion on the challenges and future development directions of synthetic promoters. Given the critical role of promoters in gene regulation, this article provides a review and outlook on the research progress of synthetic promoters, which holds reference value for the design of cellular gene circuits.