Detecting transcription factors with allosteric DNA-Silver nanocluster switches

Sensitive and efficient detection of protein markers, such as transcription factors (TFs), is an important issue in postgenomic era. In this paper, we report a DNA nanodevice, allosteric DNA-silver nanocluster switches (AgSwitches), for TFs detection. The mechanism of this nanodevice is based on the binding-induced allostery whereby the binding between AgSwitches and TFs alters the conformation of AgSwitches. This alteration brings DNA-silver nanocluster (DNA-AgNCs) and guanine-rich enhancer sequences (GRS) into close proximity, generating fluorescent enhancement for quantifications. Our results revealed that the sequence design of AgSwitches can be rationally optimized according to stimulated free energy, and we demonstrated that this method can not only be used for detecting TFs in nuclear extracts of cells, but also be developed as a tool for screening inhibitors of TFs. Overall, this work expanded the category allosteric DNA nanodevices by first introducing DNA-AgNCs into this area, and the obtained method was efficient for TFs-related investigations.