Active, Recombinant, Neddylated Human CUL4A / RBX1 Complex

Background: Cullin-4A (CUL4A) is a scaffold protein that assembles CRL4 E3 ubiquitin ligase complexes responsible for the ubiquitylation of substrates involved in DNA damage repair, DNA replication, chromatin regulation, cell cycle progression, and protein quality control. Within these complexes, CUL4A bridges substrate receptor modules through the adaptor protein DDB1 while RBX1 recruits ubiquitin-charged E2 enzymes, positioning them for efficient ubiquitin transfer. Covalent conjugation of NEDD8 to CUL4A induces the active conformation of the ligase, enhancing catalytic activity by promoting optimal positioning and dynamics of the RBX1 RING domain during ubiquitylation. This recombinant neddylated CUL4A / RBX1 complex is supplied in its activated form for in vitro reconstitution of CRL4 ligase activity and is well suited for mechanistic studies, biochemical and biophysical assays, inhibitor characterization, and targeted protein degradation research.