Target-responsive DNA translator for amplified and sensitive sensing of Myc-Max transcription factor dimer

Abstract

Myc-Max is a central eukaryotic transcription factor dimer that plays key roles in regulating cellular activities such as cell growth, proliferation, and differentiation. Selective and sensitive quantification of Myc-Max thus has valuable significances for biological studies and disease diagnosis. On the basis of a new DNA translator probe, we construct an amplified FRET sensing strategy for sensitively detecting Myc-Max in human serums via DNAzyme and clamped hybridization chain reaction (cHCR)-integrated signal amplifications. Myc-Max binds the DNA translator and switches its conformation to activate the DNAzyme and trigger cHCR for the assembly generation of DNA networks from two respective dye-labeled dual stem-loop and palindromic sequence-containing hairpin structures. Such DNA networks pull the two dyes into proximity position to exhibit highly magnified FRET responses for sensitively detecting Myc-Max with a 1.2 pM low detection limit in the dynamic range between 10 pM and 1 nM. Besides, sensitive discrimination of low levels of Myc-Max in diluted human serums has been verified by the developed method. Moreover, the sequence of the DNA translator can be tuned to accommodate different biomolecules, making the developed sensing strategy a versatile tool for detecting various trace biomarkers for diagnosing diseases at their early stages.