The WDR9 TR-FRET Assay Kit is designed to measure the inhibition of the binding of WDR9, also known as BRWD1, to its substrate in a homogeneous 384 reaction format. This FRETbased assay requires no time-consuming washing steps, making it especially suitable for high throughput screening applications. The assay procedure is straightforward and simple; a sample containing terbium-labeled donor, dye-labeled acceptor, WDR9, substrate, and an inhibitor is incubated for 2 hours. Then, the fluorescence intensity is measured using a fluorescence reader.