Summary: The TNKS1 Histone Ribosylation Colorimetric Assay Kit is designed to measure Tankyrase 1 (TNKS1) activity for screening and profiling applications. TNKS1 catalyzes the NAD-dependent addition of poly(ADP-ribose) to the substrate proteins. The key to the TNKS1 Histone Ribosylation Assay is the biotinylated NAD+ substrate. With this kit, only three simple steps are required for TNKS1 reactions. First, histone proteins are coated on a 96-well plate. Next, the biotinylated NAD+substrate is incubated with an assay buffer that contains the TNKS1 enzyme. Finally, the plate is treated with streptavidin-HRP followed by addition of the colorimetric HRP substrate to produce color that can then be measured using a UV/Vis spectrophotometer microplate reader.