CUL1 Intrachain TR-FRET Assay Kit

The CUL1 Intrachain TR-FRET Assay Kit is a homogeneous, sensitive TR-FRET (Time-Resolved Fluorescence Resonance Energy Transfer) assay kit designed to measure CUL1 (cullin 1) auto-ubiquitination. 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 CUL1, this assay measures poly-ubiquitination. The kit comes in a convenient 384-well format and contains enough purified CUL1/SKP1/SKP2/RBX1 Complex, purified UBE1 (ubiquitin-like modifier activating enzyme 1), UbcH5b (Ubiquitin-conjugating enzyme E2 D2), Ubi-Mix™, ATP, and assay buffer for 400 reactions.Figure 1. CUL1 Intrachain TR-FRET Assay Kit schematic.E1 and E2 enzymes, Europium cryptate-labeled Ubiquitin (TR-FRET donor) and Cy5-labeled Ubiquitin (TR-FRET acceptor) are incubated with CUL1 complex. The donor and acceptor are incorporated into poly-ubiquitin chains formed on CUL1, allowing energy transfer to occur. The TR-FRET signal is proportional to CUL1 activity.Need us to run inhibitor screens or profile your compounds against CUL1? Check out ourUbiquitination Screening Services.