Department of Bioengineering, Imperial College London, London SW7 2AZ, UK; Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK.
Department of Mathematics, Imperial College London, London SW7 2AZ, UK; Imperial College Centre for Synthetic Biology, Imperial College London, London SW7 2AZ, UK.
Cell Syst. 2018 Apr 25;6(4):508-520.e5. doi: 10.1016/j.cels.2018.03.013. Epub 2018 Apr 18.
To perform well in biotechnology applications, synthetic genetic oscillators must be engineered to allow independent modulation of amplitude and period. This need is currently unmet. Here, we demonstrate computationally how two classic genetic oscillators, the dual-feedback oscillator and the repressilator, can be re-designed to provide independent control of amplitude and period and improve tunability-that is, a broad dynamic range of periods and amplitudes accessible through the input "dials." Our approach decouples frequency and amplitude modulation by incorporating an orthogonal "sink module" where the key molecular species are channeled for enzymatic degradation. This sink module maintains fast oscillation cycles while alleviating the translational coupling between the oscillator's transcription factors and output. We characterize the behavior of our re-designed oscillators over a broad range of physiologically reasonable parameters, explain why this facilitates broader function and control, and provide general design principles for building synthetic genetic oscillators that are more precisely controllable.
为了在生物技术应用中表现出色，合成遗传振荡器必须经过工程设计，以允许独立调节幅度和周期。目前这一需求尚未得到满足。在这里，我们通过计算演示了如何重新设计两种经典的遗传振荡器，双反馈振荡器和阻遏子振荡器，以提供对幅度和周期的独立控制，并提高可调性，即通过输入“刻度盘”可访问的宽动态范围的周期和幅度。我们的方法通过引入一个正交的“汇模块”来解耦频率和幅度调制，在这个模块中，关键分子物种被引导进行酶降解。这个汇模块维持快速的振荡周期，同时减轻振荡器的转录因子和输出之间的翻译耦合。我们在广泛的生理合理参数范围内对我们重新设计的振荡器的行为进行了表征，解释了为什么这有助于更广泛的功能和控制，并为构建更精确可控的合成遗传振荡器提供了一般设计原则。
