 CUL4A protein is 759 amino acids long and forms an extended, rigid structure primarily consisting of alpha-helices.At the N-terminus, CUL4A binds to the beta-propeller of the DDB1 adaptor protein which interacts with numerous DDB1-CUL4-Associated Factors (DCAFs).As a result, the N-terminus is crucial for the recruitment of substrates for the ubiquitin ligase complex.