Cell-based assays to support the profiling of small molecules with histone methyltransferase and demethylase modulatory activity

Abstract

Histone methylation is a prevalent and dynamic chromatin modification, executed by the action of histone methyltransferases (HMTs) and demethylases (HDMs). Aberrant activity of many of these enzymes is associated with human disease, hence, there is a growing interest in identifying corresponding small molecule inhibitors with therapeutic potential. To date, most of the technologies supporting the identification of these inhibitors constitute in vitro biochemical assays which, although robust and sensitive, do not study HMTs and HDMs in their native cellular state nor provide information of inhibitor's cell permeability and toxicity. The evident need for complementary cellular approaches has recently propelled the development of cell-based assays that enable screening of HMT and HDM enzymes in a more relevant environment. Here, we highlight current cellular methodologies for HMT and HDM drug discovery support. We anticipate that implementation of these cell-based assays will positively impact the discovery of pharmacologically potent HMT and HDM inhibitors.

Figure 1

Antibody-based assays (a, b, c, d, e and f): After compound treatment, cells are lysed and the histone modification of interest is detected using at least one specific antibody in one of the following modalities. (a) DELFIA: histones are directly captured on a high binding plate followed by antibody binding and detection via a Europium (Eu)-labeled secondary antibody.