Molecular Biology Section, Division of Biological Science, University of California, San Diego, La Jolla, California, USA.
BioCircuits Institute, University of California, San Diego, La Jolla, California, USA.
Nat Genet. 2017 Aug;49(8):1282-1285. doi: 10.1038/ng.3915. Epub 2017 Jul 10.
A defining goal of synthetic biology is to engineer cells to coordinate tasks that often require precise temporal modulation of gene expression. Although a variety of relatively small gene circuits have been constructed and characterized, their logical combination into larger networks remains a central challenge. This is due primarily to the lack of compatible and orthogonal elements for predictable dynamic control of gene expression. As an alternative approach to promoter-level regulation, we explored the use of DNA copy number as a circuit control element. We engineered colony-wide DNA cycling in Escherichia coli in the form of plasmid copy number oscillations via a modular design that can be readily adapted for use with other gene circuitry. Copy number modulation is a generalizable principle that adds a layer of control to synthetic gene circuits, allowing dynamic regulation of circuit elements without requiring specially engineered promoters.
合成生物学的一个明确目标是设计细胞来协调任务，这些任务通常需要对基因表达进行精确的时间调节。虽然已经构建和表征了各种相对较小的基因电路，但将它们逻辑组合成更大的网络仍然是一个核心挑战。这主要是由于缺乏用于可预测的基因表达动态控制的兼容和正交元件。作为启动子水平调节的替代方法，我们探索了将 DNA 拷贝数用作电路控制元件。我们通过一种模块化设计，在大肠杆菌中以质粒拷贝数振荡的形式进行了全菌落范围的 DNA 循环，该设计可以很容易地适应其他基因电路的使用。拷贝数调节是一个可推广的原则，它为合成基因电路增加了一层控制，允许在不使用专门设计的启动子的情况下对电路元件进行动态调节。
