The NEDD4 intrachain TR-FRET Assay Kit is a sensitive high-throughput screening (HTS) TR-FRET Assay Kit, designed to measure NEDD4 auto-ubiquitination activity in a homogeneous 384 reaction format. It utilizes a Europium-labeled ubiquitin (Ub) donor as well as Cy5-labeled Ub acceptor to complete the TR-FRET pairing. Since both the TR-FRET donor and acceptor are incorporated into poly-ubiquitin chains formed on NEDD4, this assay measures poly-ubiquitination. As a homogeneous assay, it requires no time-consuming washing steps, making it especially suitable for HTS applications as well as real-time analyses.

Figure 1. E3 ligase NEDD4 intrachain TR-FRET Assay Kit schematic.