Transcription factor (TF)-based metabolite detection mainly depends on TF-regulated gene expression in cells. From TF activation to gene transcription and translation, the signal travels a relatively long way before it is received. Here, we propose a TF-splinting duplex DNA nanoswitch to detect metabolites. We show its feasibility using tryptophan repressor (TrpR) to detect l-tryptophan as a model. The assay has been optimized and characterized after obtaining a proof of concept, and the detection of l-tryptophan in complex biological samples is feasible. Unlike an equivalent gene expression approach, the whole process is a single-step, enzyme-free, and signal-on method. It can be completed within 20 min. This proposed TF-splinting duplex has the potential to be applied to the quick and convenient detection of other metabolites or even TFs.

中文翻译：

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利用TF夹层双链纳米开关实现L-色氨酸单步，无酶，信号检测的策略。

基于转录因子（TF）的代谢物检测主要取决于TF调控细胞中的基因表达。从TF激活到基因转录和翻译，信号在被接收之前传播的时间较长。在这里，我们提出了TF夹板双链DNA纳米开关来检测代谢产物。我们展示了使用色氨酸阻遏物（TrpR）检测l-色氨酸作为模型的可行性。在获得概念证明后，对测定进行了优化和表征，并且在复杂生物样品中检测l-色氨酸是可行的。与等效的基因表达方法不同，整个过程是单步，无酶和信号传递方法。可以在20分钟内完成。提出的TF夹板双链体有潜力应用于其他代谢物甚至TF的快速便捷检测。