||The posttranslational modification (PTM) of chromatin plays a crucial role in the regulation of gene transcription, DNA repair and many other cellular processes. Collectively, the combinatorial array of chromatin PTMs forms the foundation of the "Histone Code". This code is interpreted by a large family of protein motifs that selectively recognize and bind to a particular chromatin PTM. Commonly found in transcription factors and other regulatory proteins, these reader domains localize their proteins to chromatin bearing the appropriate PTM(s). Additionally, a given protein will often have multiple reader domains located adjacent to each other, potentially providing additional levels of specificity to the system. The JMJD2A Tudor Domains TR-FRET Assay Kit is a homogeneous, TR-FRET assay method amenable to rapid characterization of Tudor domain inhibitors in a high-throughput format. This screening assay is robust, displaying a Z" >0.6, and is designed to assist in the early-stage discovery and development of chromatin reader domain inhibitors.