A Label-Free Deoxyribozyme Sensor for m6A Demethylase Activity Detection†

Comprehensive Summary A label-free deoxyribozyme (DNAzyme) biosensor for m 6 A demethylase activity detection is developed. When demethylase FTO (Fat mass and obesity-associated protein), an important m 6 A demethylase of ALKBH demethylase family is present, the m 6 A group is specifically demethylated, and the cleavage activity of DNAzyme is restored. This allows the cleavage product that contains G-quadruplex sequence to bind to thioflavin T (ThT) and generate fluorescence signals. The biosensor shows high specificity and sensitivity, and fast reaction speed. Our study demonstrates a new design of allosteric DNAzyme for sensing. This method represents the first label-free nucleic acid biosensor for FTO assay, providing a feasible route towards inhibitors screening.