Post-translational histone modifications like acetylations play a pivotal role in the epigenetic regulation of transcription. Histone deacetylases (HDACs) remove acetylgroups from proteins and thereby affect protein localization, stability or enzyme activity. A high HDAC expression is found in various cancers making them suspicious of contributing to cancerogenesis. Inhibitors of HDACs are approved for treatment of hematological cancers. Current research focuses on more specific HDAC inhibitors that potentially impact on solid tumors.
In this application note, a fluorescent HDAC-activity assay is presented that uses a synthetic substrate which is HDAC-dependently converted into the fluorophore Amino-4-methylcoumarin (AMC). The assay was validated using HDAC1 and the HDAC inhibitor vorinostat. The BMG LABTECH microplate reader reliably detected the fluorescence signal and determined the HDAC1 KM value as well as the IC50 of vorinostat.