Fig. 1
Design concept and experimental validation strategy of the BiAD sensors. a An anchor domain (shown in orange) is used to recognize a specific genomic locus (shown as orange line) and a detector domain (shown in purple) is employed for the recognition of a target epigenetic modification (shown as lolly pop). Both proteins are fused to the non-fluorescent VenN and VenC parts of mVenus. The position of the chromophore is schematically indicated with a star within the VenN part. When the targeted DNA sequence is methylated, the two domains will bind in close spatial proximity, leading to the reconstitution of a functional mVenus fluorophore. This can be visualized by fluorescence microscopy. b If the detector module is deactivated by a mutation in the 5mC-binding pocket, or the sensor is expressed in cells with reduced 5mC levels, no fluorescence complementation signal is observed. c Overview of the sensors designed during the course of this study
