Posttranslational modifications on histones play crucial roles in the epigenetic regulation of eukaryotic gene expression. Chemical modifications that occur on histone tails include acetylation, methylation, phosphorylation, ubiquitination. This chemical diversity together with the positions and combinations of these modifications give rise to complex networks of highly controlled gene expression programs. The identification and characterisation of chromatin-associated proteins (or epigenetic regulators) in recent years has advanced our understanding of the significance of these histone modifications and the regulatory outcomes in development and in disease. The project aims to generate new classes of highly selective and potent chemical probes for epigenetic regulators, focusing on enzymes and proteins associated with methyl-lysine marks. A novel modified peptide-based discovery platform, which combines molecular, chemical, biophysical and cellular techniques, have been developed and applied. These chemical probes will be useful for biological and biomedical research, and will serve as potential starting points for therapeutic epigenetic intervention.