University Stuttgart, Germany
Title: Modular fluorescence complementation sensors for live cell detection of epigenetic signals at endogenous genomic loci
Biography: Albert Jeltsch
Investigation of the fundamental role of epigenetic processes depends on the development of methods, which enable live-cell detection of epigenetic modifications with locus-specific resolution. Here, we address this urgent technological demand by developing four modular fluorescence complementation-based epigenetic biosensors for live cell microscopy applications. In these tools, we combine the high DNA sequence specificity of engineered anchor proteins, with the great versatility of chromatin reading domains as natural detector modules for the recognition of target epigenetic marks. Simultaneous readout of DNA sequence and epigenetic mark is detected as reconstituted fluorescent signals that arise upon binding of the anchor and detectors modules in close spatial proximity, within the nuclei of living cells. With this approach we could directly detect DNA methylation and histone 3 lysine 9 trimethylation at defined, endogenous genomic sites, in several mouse and human cell lines. Furthermore, we could follow dynamic changes in these marks with locus-specific resolution upon drug treatment or induction of epigenetic enzymes. We anticipate that this versatile technology will play an important role in improving our understanding of how specific epigenetic signatures are set, erased and maintained during embryonic development or the onset of diseases.