Accepts the ubiquitin-like protein NEDD8 from the UBA3-NAE1 E1 complex and catalyzes its covalent attachment to other proteins. Together with the E3 ubiquitin ligase RNF7/RBX2, specifically neddylates cullin-5 (CUL5). Does not neddylate CUL1, CUL2, CUL3, CUL4A or CUL4B. Mediates neddylation of the CUL9-RBX1 complex 